JP2020185099A - Ophthalmologic apparatus, control method thereof, ophthalmologic information processing apparatus, control method thereof, program, and recording medium - Google Patents

Abstract

To evaluate an effect of an orthokeratology lens for a patient's eye.SOLUTION: An ophthalmologic apparatus according to an exemplary aspect includes a cornea shape measuring part, an ocular fundus shape measuring part, an eyeball model creation part, and an evaluation part. The cornea shape measuring part measures a cornea shape of the eye after an orthokeratology lens is removed. The ocular fundus shape measuring part measures an ocular fundus shape of the eye. The eyeball model creation part creates an eyeball model based at least on cornea shape data acquired by the cornea shape measuring part and ocular fundus shape data acquired by the ocular fundus shape measuring part. The evaluation part executes a first evaluation on an effect of the orthokeratology lens for the eye based at least on the eyeball model created by the eyeball model creation part.SELECTED DRAWING: Figure 1

Description

The present invention relates to an ophthalmic apparatus, a control method thereof, an ophthalmic information processing apparatus, a control method thereof, a program, and a recording medium.

Recent studies on the progression of myopia have reported that the focal point of the peripheral visual field is located deeper than the retinal surface, which may cause myopia to progress as the retina tries to displace to the back ( For example, see Non-Patent Document 1).

One of the refraction correction means for increasing the refractive power in the peripheral visual field (that is, making the refractive power in the peripheral portion negative or relatively decreasing the refractive power in the central portion) for the purpose of suppressing the progression of myopia. Orthokeratology (hereinafter abbreviated as "Ortho K") has been performed, and its effect has been clinically demonstrated (see, for example, Non-Patent Document 2).

Ortho-K is a corneal correction therapy that treats refractive errors such as myopia by wearing contact lenses (Ortho-K lenses) with a special curve design to correct the shape of the cornea. In Ortho K, the refraction correction effect is maintained for a certain period of time even after the contact lens is removed, so that it is also applicable as a refraction correction method for contact competitions and outdoor competitions.

As mentioned above, the refraction state of the peripheral visual field (peripheral part) is considered to be important for suppressing the progression of myopia, but since the patient basically uses the central visual field (fovea centralis) during daytime activity, The expected refraction correction effect is actually obtained without being conscious of what the refraction state of the peripheral vision is (that is, whether or not the Ortho K lens was mounted in an appropriate position at night). It is difficult to judge whether it is.

Earl L. Smith III, Li-Fang Hung, Juan Huang, “Relative peripheral hyperopic defocus alters central refraction development in infant monkeys”, Vision Research, Volume 49, Issue 19, 30 September 2009, Pages 2386-2392 Jun-Kang Si, Kai Tang, Hong-Sheng Bi, Da-Dong Guo, Jun-Guo Guo, and Xing-Rong Wang, “Orthokeratology for Myopia Control: A Meta-analysis”, Optometry and Vision Science, Vol. 92, No. 3, March 2015, Pages 252-257

An object of the present invention is to enable evaluation of the effect of an ortho-K lens on a patient's eye.

The ophthalmic apparatus according to some exemplary embodiments includes a corneal shape measuring unit for measuring the corneal shape of the eye after removing the orthokeratology lens, a corneal shape measuring unit for measuring the fundus shape of the eye, and the corneal shape. An eye model creating unit that creates an eye model based on at least the corneal shape data acquired by the measuring unit and the fundus shape data acquired by the fundus shape measuring unit, and the orthokeratology for the eye based on at least the eye model. -Includes an evaluation unit that performs the first evaluation of the effect of the lens.

In the ophthalmic apparatus according to some exemplary embodiments, the evaluation unit includes a focal position specifying unit that specifies the focal position of a virtual light beam incident on the fundus peripheral portion of the eyeball model, and the focal position and the fundus peripheral portion. Includes a first evaluation execution unit that executes the first evaluation based on the positional relationship of.

The ophthalmologic apparatus according to some exemplary embodiments further includes an alignment unit that aligns the fundus shape measuring unit with respect to the eye, and the eyeball model creating unit further includes the fundus shape data based on the alignment result by the alignment unit. An eyeball model is created based on at least the corneal shape data and the fundus shape data in which the tilt angle is corrected, including an tilt angle correction unit that corrects the tilt angle of the eyeball.

In the ophthalmic apparatus according to some exemplary embodiments, the eyeball modeling unit determines the relative position of the corneal shape data and the fundus shape data based on at least the predetermined anterior segment reference position and the fundus reference position. Create an eye model.

In the ophthalmic apparatus according to some exemplary embodiments, the eyeball model-creating unit performs the corneal shape data and the corneal shape data based on at least the corneal apex position as the anterior segment reference position and the foveal position as the fundus reference position. An eyeball model is created by determining the position relative to the fundus shape data.

In the ophthalmic apparatus according to some exemplary embodiments, the eyeball model creating unit further determines the relative positions of the corneal shape data and the fundus shape data based on predetermined axial length data to create an eyeball model. ..

In the ophthalmic apparatus according to some exemplary embodiments, the eyeball modeling unit has the corneal shape data and the corneal shape data based on at least the pupil center position as the anterior segment reference position and the foveal position as the fundus reference position. An eyeball model is created by determining the position relative to the fundus shape data.

In the ophthalmic apparatus according to some exemplary embodiments, the eye model creation unit further determines the relative position of the corneal shape data and the fundus shape data based on predetermined axial length data and anterior chamber depth data. Create an eye model.

In the ophthalmic apparatus according to some exemplary embodiments, the eyeball modeling unit includes an anterior segment reference position identifying portion that analyzes the corneal shape data to identify an anterior segment reference position.

In the ophthalmologic apparatus according to some exemplary embodiments, the fundus shape measuring unit includes an OCT unit that applies optical coherence tomography to the fundus of the eye to generate OCT data, and an OCT unit that analyzes the OCT data to form the fundus shape. The eyeball model creating unit includes a fundus shape data generation unit that generates data, and includes a fundus reference position specifying unit that analyzes the OCT data and specifies a fundus reference position.

In an ophthalmic apparatus according to some exemplary embodiments, a specific site detection unit that detects a specific site of the eye and a feature point setting unit that sets a feature point from corneal shape data acquired by the corneal shape measurement unit are provided. Further including, the evaluation unit performs a second evaluation regarding the wearing state of the orthokeratology lens with respect to the eye based on the specific portion and the feature point.

In the ophthalmic apparatus according to some exemplary embodiments, the feature point setting unit sets feature points based on an approximate expression of the corneal shape data by a centrally symmetric expression.

In the ophthalmic apparatus according to some exemplary embodiments, the feature point setting unit sets the center of the approximate expression as the feature point.

In the ophthalmic apparatus according to some exemplary embodiments, the corneal shape measuring unit acquires the curvature distribution data or the radius of curvature distribution data of the cornea as the corneal shape data.

In the ophthalmic apparatus according to some exemplary embodiments, the corneal shape measuring unit acquires the height distribution data of the cornea as the corneal shape data.

A method according to some exemplary embodiments is a method of controlling an ophthalmologic apparatus including an imaging unit that photographs the eye, an OCT unit that applies optical coherence stromography to the fundus, and a processor, wherein the orthokeratology lens is used. To control the imaging unit to acquire a captured image of the eye after removal, to control the OCT unit to acquire OCT data of the fundus of the eye, and to acquire corneal shape data of the eye. The processor is controlled to analyze the captured image, the processor is controlled to analyze the OCT data in order to acquire the fundus shape data of the eye, and the corneal shape data and the fundus shape data are obtained. The processor is controlled to create an eye model based on at least the eye model, and the processor is controlled to perform a first evaluation of the effect of the orthokeratology lens on the eye based on at least the eye model.

A method according to some exemplary embodiments is a method of controlling an ophthalmic apparatus including an imaging unit and a processor for photographing the eye, wherein the photographed image of the eye after removing the orthokeratology lens is obtained. The imaging unit is controlled, the processor is controlled to receive the OCT data acquired by applying optical coherence stromography to the fundus of the eye, and the captured image is analyzed to acquire the corneal shape data of the eye. The processor is controlled so as to analyze the OCT data in order to acquire the fundus shape data of the eye, and the eyeball model is based on at least the corneal shape data and the fundus shape data. The processor is controlled to create the eye, and the processor is controlled to perform a first evaluation of the effect of the orthokeratology lens on the eye based on at least the eye model.

A program according to some exemplary embodiments is a program that causes an ophthalmic apparatus including a computer to execute a control method according to any of the exemplary embodiments.

A method according to some exemplary embodiments is a method of controlling an ophthalmic apparatus including an OCT unit and a processor that applies optical coherence tomography to the fundus of the eye, in which the eye is photographed after the orthokeratology lens is removed. The processor is controlled to receive the acquired captured image, the OCT unit is controlled to acquire the OCT data of the fundus of the eye, and the captured image is analyzed to acquire the corneal shape data of the eye. The processor is controlled so as to analyze the OCT data in order to acquire the fundus shape data of the eye, and the eyeball model is based on at least the corneal shape data and the fundus shape data. The processor is controlled to create the eye, and the processor is controlled to perform a first evaluation of the effect of the orthokeratology lens on the eye based on at least the eye model.

The ophthalmologic information processing apparatus according to some exemplary embodiments includes a photographed image analysis unit that analyzes the photographed image of the eye after removing the orthokeratology lens to acquire corneal shape data, and an optical coherent motor on the fundus of the eye. An OCT data analysis unit that analyzes OCT data acquired by applying graphics to acquire fundus shape data, and an eye model creation unit that creates an eyeball model based on at least the corneal shape data and the fundus shape data. Includes an evaluation unit that performs a first evaluation of the effect of the orthokeratology lens on the eye, at least based on the eye model.

A method according to some exemplary embodiments is a method of controlling an ophthalmic information processing apparatus including a processor, wherein the processor is used to capture an image obtained by photographing the eye after removing the orthokeratology lens. To control the processor to receive OCT data acquired by applying optical coherence stromography to the fundus of the eye, and to analyze the captured image to acquire the corneal shape data of the eye. Controls the processor to analyze the OCT data in order to acquire the fundus shape data of the eye, and creates an eyeball model based on at least the corneal shape data and the fundus shape data. The processor is controlled so as to perform a first evaluation of the effect of the orthokeratology lens on the eye based on at least the eye model.

A program according to some exemplary embodiments is a program that causes a computer to execute a control method according to any of the exemplary embodiments.

The recording medium according to some exemplary embodiments is a computer-readable non-temporary recording medium on which the program according to any of the exemplary embodiments is recorded.

According to an exemplary embodiment, it is possible to perform an assessment of the effect of the Ortho K lens on the patient's eye.

It is the schematic which shows the structure of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on an exemplary aspect. It is a schematic diagram for demonstrating the process performed by the ophthalmic apparatus which concerns on an exemplary aspect. It is a schematic diagram for demonstrating the process performed by the ophthalmic apparatus which concerns on an exemplary aspect. It is a flowchart which shows the operation of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on an exemplary aspect. It is a flowchart which shows the operation of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on an exemplary aspect. It is a flowchart which shows the operation of the ophthalmic apparatus which concerns on an exemplary aspect. It is a flowchart which shows the operation of the ophthalmic apparatus which concerns on an exemplary aspect. It is a flowchart which shows the operation of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic for demonstrating the operation of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic for demonstrating the operation of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic for demonstrating the operation of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic for demonstrating the operation of the ophthalmic apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic information processing apparatus which concerns on an exemplary aspect. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on the modification. It is the schematic which shows the structure of the ophthalmic apparatus which concerns on the modification. It is the schematic for demonstrating the operation of the ophthalmic apparatus which concerns on a modification. It is the schematic for demonstrating the operation of the ophthalmic apparatus which concerns on a modification. It is the schematic for demonstrating the operation of the ophthalmic apparatus which concerns on a modification. It is the schematic for demonstrating the operation of the ophthalmic apparatus which concerns on a modification.

Some exemplary embodiments of the embodiments will be described below. In addition, the matters disclosed in the documents cited in this specification and the matters relating to any known technology can be incorporated in an exemplary manner.

Some exemplary embodiments described below are for assessing the effect of an ortho-K lens on the patient's eye, i.e., determining whether the expected effect of the ortho-K lens is adequately exerted on the patient's eye. It can be used.

This assessment includes at least an assessment of the fundus and may further include an assessment of the cornea. The assessment of the fundus typically includes determining whether or not the ortho-K lens places the focal point of the peripheral vision in front of the retinal surface (on the corneal side). The evaluation of the cornea is typically an evaluation of whether or not the cornea has been corrected to the desired shape by the Ortho-K lens. The evaluation of the fundus and the evaluation of the cornea are not independent of each other. For example, if the Ortho-K lens is not placed in the proper position on the cornea, the cornea will not be deformed into the expected shape and therefore the focal point of the peripheral vision will not be placed in the expected position.

In some aspects described below, the "correction center" refers to the detection position of the apex of the cornea deformed by the ortho-K lens (corneal apex) and the center of the corneal shape deformed by the ortho-K lens (deformation). It may mean any of the estimated positions of the center).

The corneal apex referred to here is the most protruding position in the cornea after the ortho-K lens is removed, and is generally biased from the original corneal apex (the apex of the cornea in a state where there is no influence of deformation by the ortho-K lens). (Of course, it does not exclude the situation where the corneal apex under the influence of the Ortho-K lens matches the original corneal apex).

The detection of the corneal apex is performed, for example, by detecting an index formed in the anterior segment of the eye. As a typical example thereof, Japanese Patent Application Laid-Open No. 2015-85081 takes a picture from the front while projecting a luminous flux on the anterior segment of the eye, and analyzes the image of the anterior segment obtained thereby to obtain a bright spot image (Pulkinje image). Is disclosed, and a technique for obtaining the position (two-dimensional position) of this bright spot image as the position of the apex of the cornea is disclosed. Further, Japanese Patent Application Laid-Open No. 2017-74115 captures images from two directions (stereo imaging) while projecting a luminous flux onto the anterior segment of the eye, and analyzes the two images of the anterior segment obtained thereby to obtain a bright spot image (bright spot image). A technique for detecting a Pulkinje image) and determining the position (three-dimensional position) of this bright spot image as the position of the apex of the cornea is disclosed. As another example of detecting the corneal apex, the central position of the photographed image of the ring pattern light projected on the cornea for measuring the radius of curvature of the cornea can be obtained and set as the position of the corneal apex (two-dimensional position). An ophthalmic apparatus (keratometer) for measuring the radius of curvature of the cornea is disclosed in, for example, Japanese Patent Application Laid-Open No. 2-65533. As yet another example of corneal apex detection, the position (three-dimensional position) of the corneal apex is detected from the image of the anterior segment obtained by an optical coherence tomography (OCT) device (for example, Japanese Patent Application Laid-Open No. 2015-157182). can do.

The deformation center is estimated, for example, by finding the center of a mathematical formula (function) that approximates the shape of the cornea (typically, the center of the fitting curved surface and the center of the fitting curve). This mathematical expression (function) may be, for example, a centrally symmetric mathematical expression (function), or may be an aspherical expression (a mathematical expression (function) representing an aspherical shape). This aspherical expression may be, for example, an expression (function) including at least a conic surface expression (function) or a biconic surface expression (function), and further, an even-order polynomial in the conic surface expression (function). It may be an expression (function) obtained by adding the above, or an expression (function) obtained by adding an even-order polynomial to the expression (function) of the biconic surface.

The Ortho-K lens has a region (transition zone, return zone) in which a curvature inflection point exists between the central portion (optical zone, treatment zone) and the peripheral portion (peripheral zone, landing zone). Therefore, since the fitting accuracy is low only on the conic surface or the biconic surface, it is considered desirable to increase the fitting accuracy by adding a polynomial up to the fourth order, the sixth order, or the eighth order, for example.

The corneal shape to be approximated may be, for example, a corneal curvature distribution, a corneal radius of curvature distribution, or a height distribution. The corneal curvature distribution and the corneal radius of curvature distribution are determined by, for example, a keratometer and a corneal topogram (see, for example, Japanese Patent Application Laid-Open No. 8-280624). The height distribution is determined, for example, by integrating the corneal curvature distribution twice. The estimation of the deformation center (particularly the fitting center) will be described later.

In some of the following embodiments, the "processor" is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (for example, a SPLD), a programmable logic device (SPLD). , CPLD (Complex Programmable Logic Device), FPGA (Field Programmable Gate Array)) and the like. The processor realizes a desired function by reading and executing a program stored in a storage circuit or a storage device, for example.

<First aspect>
The ophthalmic apparatus according to the first aspect will be described. A configuration example of the ophthalmic apparatus according to this aspect is shown in FIG. The ophthalmic apparatus 1000 includes a corneal shape measuring unit 1010, a fundus shape measuring unit 1020, an eyeball model creating unit 1030, and an evaluation unit 1040. The ophthalmic apparatus 1000 further includes a control unit 1050 that controls them.

The corneal shape measuring unit 1010 measures the corneal shape of the eye and generates corneal shape data. The corneal shape data includes, for example, corneal curvature distribution data or corneal radius of curvature distribution data obtained by a keratometer, corneal curvature distribution data or corneal radius of curvature distribution data obtained by a corneal topographer, and other measurements, as described above. One of the data.

A typical corneal shape measuring unit 1010 includes a projection system that projects light for forming a pattern image on the cornea and an imaging unit (optical system, image sensor, camera) that photographs the anterior segment on which the pattern image is formed. Etc.) and a processor that analyzes the image obtained by the photographing unit. The processor operates according to, for example, analysis software (program) for obtaining distribution data of corneal shape parameters.

The fundus shape measuring unit 1020 measures the fundus shape of the eye and generates fundus shape data. A typical fundus shape measuring unit 1020 includes a fundus data acquisition unit (optical system, imaging element, drive mechanism, processor, etc.) that acquires fundus data, and a processor that analyzes the acquired fundus data. The fundus data acquisition unit includes, for example, a group of elements for applying an OCT scan to the fundus. Alternatively, the fundus data acquisition unit may include a stereo fundus camera (see, for example, Japanese Patent Application Laid-Open No. 09-313443). The processor operates according to, for example, analysis software (program) for obtaining distribution data of fundus shape parameters.

The type of OCT applicable to this aspect is arbitrary, typically swept source OCT or spectral domain OCT, but may be other types. Here, the swept source OCT divides the light from the variable wavelength light source into the measurement light and the reference light, and superimposes the return light of the measurement light from the test object on the reference light to generate interference light, and this interference This is a method of constructing an image by detecting light with an optical detector and performing Fourier conversion or the like on the detection data collected in response to sweeping the wavelength and scanning the measurement light. On the other hand, the spectral domain OCT divides the light from the low coherence light source (broadband light source) into the measurement light and the reference light, and superimposes the return light of the measurement light from the test object on the reference light to generate interference light. This is a method in which the spectral distribution of this interference light is detected by a spectroscope, and the detected spectral distribution is subjected to Fourier transform or the like to construct an image. That is, the swept source OCT is an OCT method for acquiring the spectral distribution of interference light by time division, and the spectral domain OCT is an OCT method for acquiring the spectral distribution of interference light by spatial division.

When applying an OCT scan to the fundus, a fixation target is typically projected onto the measurement optical axis of the optical system of the ophthalmic apparatus 1000. This OCT scan may be, for example, a radial scan centered on the macula (fovea centralis). As a result, a B-scan image of the central part of the fundus is acquired. In addition, B-scan images along the tangential plane and the sagittal plane are acquired.

The fundus shape measuring unit 1020 performs segmentation on the B-scan image acquired by using the OCT scan to perform segmentation on a predetermined layer region (for example, the OS-RPE interface having the highest brightness value (external segment of photoreceptor-retinal pigment). The epithelial interface) is identified, and the height data [pixel] of the layer region in the B scan image is acquired. The height data is the distribution of the distance of the layer region from a predetermined reference position measured along the depth direction. Corresponds to.

The fundus shape measuring unit 1020 converts the height data expressed in the pixel unit value into the millimeter unit value by using the device-specific pixel spacing correction value [mm / pixel] specified according to the OCT optical system. To do. The height data thus obtained can be used as fundus shape data.

The fundus shape data may be data of another aspect. For example, similar to the corneal shape data, the fundus shape data is the curvature distribution data or the radius of curvature distribution data in a predetermined layer structure of the fundus (for example, the fundus surface (inner boundary membrane (ILM)), OS-RPE interface, etc.). There may be.

The eyeball model creating unit 1030 creates an eyeball model based on at least the corneal shape data acquired by the corneal shape measuring unit 1010 and the fundus shape data acquired by the fundus fundus shape measuring unit 1020.

The eyeball model creation unit 1030 creates an eyeball model by applying, for example, corneal shape data and fundus shape data to a known model eye. The type of model eye used in creating the eyeball model is arbitrary. For example, the Bullstrand model eye, Navarro model eye, and Liou-Brennan model eye disclosed in Japanese Patent Application Laid-Open No. 2012-93522 and Japanese Patent Application Laid-Open No. 2017-526517. , Badal model eye, Arizona model eye, Indiana model eye, any standardized model eye, and any of these and equivalent model eyes.

The eyeball model creating unit 1030 may be configured to determine the relative position between the corneal shape data and the fundus shape data based on at least the predetermined anterior segment reference position and the fundus reference position to create the eyeball model. For example, the eyeball model creation unit 1030 determines the position of the corneal shape data in the eyeball model based on the predetermined anterior segment reference position, and determines the position of the fundus shape data in the eyeball model based on the predetermined fundus reference position. It may be configured to perform processing.

For example, the anterior segment reference position may be the corneal apex position after the ortho-K lens is removed, or the corneal apex position (original corneal apex position) before the ortho-K lens is attached, and / or. The fundus reference position may be the foveal position. Typically, the eyeball model creation unit 1030 arranges the corneal shape data so that the anterior segment reference position (corneal apex position) coincides with the corneal apex in a known model eye, and is set in the model eye. An eye model can be created by arranging the corneal shape data so that the reference position of the cornea (fovea position) coincides with the fovea centralis.

When the anterior segment reference position is based on the cornea (for example, when the anterior segment reference position is the corneal apex position), the eyeball model creation unit 1030 may, for example, perform corneal shape data based on at least the predetermined axial length data. The eyeball model can be created by determining the relative position between the eyeball and the fundus shape data. In this example, the eyeball model creation unit 1030 creates an eyeball model so that the corneal apex position in the corneal shape data and the fovea centralis position in the fundus shape data are arranged via the distance indicated by the axial length data. It may be configured. Alternatively, the eyeball model creating unit 1030 may be configured to deform the model eye based on the distance indicated by the axial length data and apply the corneal shape data and the fundus shape data to the deformed model eye. The axial length data may be a standard value such as an axial length value in a model eye, or may be a measured value of the axial length of the patient's eye. The axial length measurement is performed by, for example, a known optical method such as OCT, or a known method using ultrasonic distance measurement.

The anterior segment reference position is not limited to the corneal apex position, and may be, for example, the pupil center position. In this case, the fundus reference position may be the foveal position. Typically, the eyeball model creation unit 1030 arranges the corneal shape data so that the corneal apex position corresponding to the anterior segment reference position (pupil center position) coincides with the corneal apex in a known model eye, and An eyeball model can be created by arranging the corneal shape data so that the reference position of the cornea (fovea position) coincides with the fovea set in the model eye. Here, the corneal apex position corresponding to the pupil center position may be specified as, for example, a position separated from the pupil center position by a predetermined distance along the axial direction of the model eye in the corneal direction, or may be defined as a position separated from the pupil center position. The straight line connecting the foveal position may be specified as the position where it intersects the corneal surface of the model eye.

When the anterior segment reference position is based on the pupil (for example, when the anterior segment reference position is the pupil center position), the eyeball model creation unit 1030 obtains, for example, predetermined axial length data and anterior chamber depth data. The eyeball model can be created by determining the relative position between the corneal shape data and the fundus shape data based on at least the basis. In this example, the eyeball model creation unit 1030 deviates from the center of the pupil (along the eye axis) by the distance indicated by the anterior chamber depth data (estimated position of the corneal apex) and the shape of the fundus of the eye in the corneal shape data. The eye model may be configured such that the foveal position in the data is located over the distance indicated by the axial length data. Alternatively, the eyeball model creation unit 1030 deforms the model eye based on the distance indicated by the axial length data and the distance indicated by the anterior chamber depth data, and applies the corneal shape data and the fundus shape data to the deformed model eye. It may be configured. The axial length data may be a standard value such as an axial length value in a model eye, or may be a measured value of the axial length of the patient's eye. The anterior chamber depth data may be a standard value such as an anterior chamber depth value in a model eye, or a measured value of the anterior chamber depth of a patient eye. The anterior chamber depth is measured by, for example, a known optical method such as OCT or a known method using ultrasonic distance measurement.

A typical eye model creation unit 1030 includes a processor that creates an eye model based on at least the corneal shape data and the fundus shape data. The processor operates according to the eye model creation software (program) for executing the eye model creation.

The evaluation unit 1040 executes an evaluation (first evaluation) regarding the effect of the ortho-K lens on the eye based on at least the eyeball model created by the eyeball model creation unit 1030. The first evaluation can be used to determine whether or not the expected effect of the Ortho-K lens is sufficiently exerted on the patient's eye, and corresponds to the above-mentioned evaluation on the fundus. The first evaluation typically includes determining whether or not the focal point of the peripheral visual field is located in front of the retinal surface (corneal side) by the ortho-K lens.

A typical evaluation unit 1040 includes a processor that performs a first evaluation based on at least an eye model. The processor operates according to the evaluation software (program) for performing the first evaluation.

The control unit 1050 controls each unit of the ophthalmic apparatus 1000. The control unit 1050 includes a processor that operates according to the control program.

Although not shown, the ophthalmic apparatus 1000 may further include a display device, an operation device, a communication device, and the like.

Some modifications of the ophthalmic apparatus 1000 according to this aspect will be described below.

A first modification is shown in FIG. 2A. The eyeball model creation unit 1030A of this modified example is an example of the eyeball model creation unit 1030, and includes an anterior eye portion reference position specifying unit 1031. The anterior segment reference position specifying unit 1031 identifies the anterior segment reference position by analyzing the corneal shape data acquired by the corneal shape measuring unit 1010. The eye model creation unit 1030A can create an eye model using the anterior eye reference position specified from the corneal shape data by the anterior eye reference position specifying unit 1031. The anterior segment reference position is typically the apex position of the cornea or the center position of the pupil, but may be another position.

For the identification of the apex position of the corneum, for example, as described above, a two-dimensional position or three-dimensional position detection method based on the Purkinje image, a two-dimensional position detection method based on the keratling image, and anterior segment OCT were used. One of the three-dimensional position detection methods and other detection methods is applied.

To identify the center position of the pupil, for example, a two-dimensional position detection method by analyzing the front image of the anterior segment of the eye, and a three-dimensional position detection method by analyzing two anterior segment images obtained by photographing from two directions. , And any of the other detection methods apply.

A typical anterior segment reference position specifying unit 1031 includes an imaging unit (optical system, image sensor, camera, etc.) that photographs the anterior segment, and a processor that analyzes an image obtained by the imaging unit. Further, the anterior segment reference position specifying unit 1031 may include a projection unit that projects a luminous flux for forming a Purkinje image or a keratling image. The processor operates according to, for example, analysis software (program) for identifying the anterior segment reference position.

A second modification is shown in FIG. 2B. The fundus shape measuring unit 1020A of this modified example is an example of the fundus shape measuring unit 1020, and includes an OCT unit 1021 and a fundus shape data generating unit 1022. Further, the eyeball model creating unit 1030B of this modified example is an example of the eyeball model creating unit 1030, and includes a fundus reference position specifying unit 1032.

The OCT unit 1021 is an example of the above-mentioned fundus data acquisition unit in the fundus shape measuring unit 1020, and applies an OCT scan to the fundus to generate OCT data. The OCT data may be interference signal data acquired by the OCT interference optical system, reflection intensity profile data obtained by applying signal processing (Fourier conversion, etc.) to the interference signal data, or reflection intensity profile data. Image data expressed by pixel values may be used.

The fundus shape data generation unit 1022 analyzes the OCT data acquired by the OCT unit 1021 and generates the fundus shape data. A typical fundus shape data generation unit 1022 includes a processor that analyzes OCT data and generates fundus shape data. The processor operates according to, for example, analysis software (program) for generating fundus shape data.

The fundus reference position specifying unit 1032 identifies the fundus reference position by analyzing the OCT data acquired by the OCT unit 1021. The eyeball model creating unit 1030B can create an eyeball model using the fundus reference position specified from the OCT data by the fundus reference position specifying unit 1032. The fundus reference position is typically the foveal position, but may be another position (such as the optic disc position).

To identify the foveal position, for example, segmentation to identify the ILM region by analyzing OCT data, smoothing to remove noise in the identified ILM region, and a downwardly convex position in the smoothed ILM region. Includes processing to identify.

A typical fundus reference position identifying unit 1032 includes a processor that analyzes OCT data. The processor operates according to, for example, analysis software (program) for identifying a fundus reference position.

A third modification is shown in FIG. 2C. The evaluation unit 1040A of this modification is an example of the evaluation unit 1040, and includes a focus position specifying unit 1041 and a first evaluation execution unit 1042.

The focal position specifying unit 1041 specifies the focal position of the virtual light beam incident on the fundus peripheral portion of the eyeball model created by the eyeball model creating unit 1030. The focal position specifying unit 1041 is, for example, a process of calculating the refractive power corresponding to the peripheral part of the fundus based on the eyeball model and a process of obtaining the focal position of the virtual light ray incident on the peripheral part of the fundus based on the calculated refractive power. Is configured to do.

A typical focus positioning unit 1041 includes a processor that obtains a focus position based on an eyeball model. The processor operates according to software (program) for executing analysis, calculation, and simulation based on, for example, an eyeball model.

The first evaluation execution unit 1042 executes the first evaluation based on the positional relationship between the focal position specified by the focal position specifying unit 1041 and the peripheral portion of the fundus. For example, the first evaluation execution unit 1042 determines whether the focal position is located on the corneal side of the retinal surface (ILM) in the peripheral portion of the fundus. Typically, the first evaluation execution unit 1042 determines whether the focal position is located within the vitreous region. When the focal position is located closer to the cornea than the surface of the retina (when the focal position is located within the vitreous region), the evaluation result shows that the ortho-K lens exerts the effect of suppressing the progression of myopia. Be done. On the other hand, when the focal position is located behind the surface of the retina (when the focal position is not located within the vitreous region), the evaluation result that the ortho-K lens does not exert the effect of suppressing the progression of myopia. Is obtained.

A typical first evaluation execution unit 1042 includes a processor that operates according to software (program) for the first evaluation.

Some examples of the process executed by the focal position specifying unit 1041 in order to calculate the refractive power corresponding to the peripheral portion of the fundus based on the eyeball model will be described below. The refractive power corresponding to the peripheral part of the fundus is also expressed as the refractive power of the peripheral region of the eye.

The first example of the peripheral refraction power calculation process will be described. The focal position specifying unit 1041 calculates the refractive power of the peripheral region based on the refractive power of the central region acquired in advance by a reflex meter or the like and an eyeball model (for example, fundus shape). The focal position specifying unit 1041 can calculate the refractive power of the peripheral region using the parameters of the eyeball model.

As described above, height data can be used as fundus shape data in creating the eyeball model.

See FIG. 2D. FIG. 2D schematically represents some of the parameters of the eye model.

As shown in FIG. 2D, the focal position specifying unit 1041 sets a device-specific pivot point Pv between the cornea Ec and the fundus Ef in the eyeball model. Typically, the pivot point Pv is deviated by 3 mm from the corneal Ec to the back side at a position corresponding to a position (pupil position) optically conjugate with an optical scanner of an OCT scan system (for example, a galvano mirror). (Position) is set. The region (ELS) located equidistant (equidistant length) with respect to the pivot point Pv corresponds to a flat region in the B scan image obtained by the OCT scan.

In the eye model, the axial length AL and the distance Lp from the anterior surface (posterior surface) of the cornea to the pivot point Pv are known, and therefore, the distance (AL-Lp) from the pivot point Pv to the fundus Ef is also known. When the radius of curvature of the fundus Ef is equal to the distance (AL-Lp), the fundus Ef corresponds to the flat region in the B-scan image as described above. Therefore, the focal position specifying unit 1041 can specify the shape of the fundus Ef (for example, the radius of curvature) from the distance [mm] of the obtained height data.

Therefore, the focal position specifying unit 1041 obtains the difference in height (fundus shape difference data) Δh [mm] of the peripheral region with respect to the central region (fovea centralis). The difference Δh may be obtained for each A line in the B scan image, or may be fitted by an arbitrary function such as a polynomial or an aspherical expression (polynomial including a conic constant).

For example, the focal position specifying unit 1041 defines the optical power of the whole eye system in order to relate the fundus shape and the refractive power. In a typical eye model (Gullstrand model eye (precision model eye, accommodative dormant state)), the optical power of the whole eye system is 58.64 [diopter]. In terms of air equivalent length, the focal length of the whole eye system is "1000 / 58.64 = 17.05" [mm]. The unit [mm] information obtained using the pixel spacing correction value usually represents the distance in the living tissue, so the focal length of the whole eye system in the living tissue is calculated by multiplying the refractive index. It is calculated. Assuming that the equivalent refractive index of the whole eye system is n = 1.38, the focal length ft of the whole eye system in the living tissue is “1000 / 58.64 × 1.38 = 23.53” [mm].

The focal position specifying unit 1041 calculates the difference ΔD of the refractive power of the eyeball at the position of the difference Δh in the height of the peripheral region with respect to the central region (fovea centralis) according to the following equation: ΔD = (1000 / (23.53-Δh)). -(1000 / 23.53). The difference ΔD corresponds to the difference in the refractive power of the eyeball relative to the central region including the fovea centralis.

For example, when Δh = 0.1 [mm] (tissue), ΔD = 0.18 [diopter].

As shown in the following equation, the focal position specifying unit 1041 can obtain the refractive power SEp of the peripheral region by applying the difference ΔD to the equivalent spherical power SE of the central region: SEp = SE + ΔD.

Here, the focal position specifying unit 1041 may obtain the refractive power of the peripheral region in the B-scan image for each A-line, or may be fitted by an arbitrary function.

A second example of the peripheral refraction power calculation process will be described. This example provides a method of calculating the refractive power of the peripheral region using the axial length data of the eye (measured value of the axial length). In this example, an eyeball model is created using the axial length data.

The focal position specifying unit 1041 obtains the difference in height of the peripheral region (fundus shape difference data) Δh [mm] with respect to the central region (fovea centralis) using an eyeball model in which the axial length data is reflected. Further, the focal position specifying unit 1041 obtains the difference ΔD of the eyeball refractive power using the obtained difference Δh, and calculates the refractive power of the peripheral region using the obtained difference ΔD.

A third example of the peripheral refraction power calculation process will be described. This example provides a method of calculating the refractive power of the peripheral region using the corneal shape data (measured value of the corneal shape) of the eye. As described above, the eye model is created based on the corneal shape data.

The focal position specifying unit 1041 obtains a difference Δh [mm] in height of the peripheral region with respect to the central region (fovea centralis) using an eyeball model in which the corneal shape data is reflected. Further, the focal position specifying unit 1041 obtains the difference ΔD of the eyeball refractive power using the obtained difference Δh, and calculates the refractive power of the peripheral region using the obtained difference ΔD.

A fourth example of the peripheral refraction power calculation process will be described. In this example, the periphery is performed by performing ray tracing processing using an eyeball model that reflects multiple measured data of the eye (for example, measured values of axial length, corneal shape, anterior chamber depth, crystalline lens curvature, and crystalline lens thickness). A method for calculating the refractive index of a region is provided.

The focal position specifying unit 1041 performs ray tracing processing on a virtual ray that is incident from the cornea Ec, passes through the pupil, and reaches the fundus Ef using an eyeball model that reflects a plurality of actually measured data (for example, pupil diameter = φ4). In the ray tracing process, for example, a position corresponding to a far point obtained from the refractive power (equivalent spherical power SE) in the central region is set as the position of the object point. The distance (far point distance) L from the corneal Ec to the position corresponding to the far point is "-1000 / SE" [mm].

First, the focal position specifying unit 1041 performs ray tracing processing on the central region. Since the eyeball model that reflects the measured data is used, there is a possibility that the light rays do not converge at the fundus Ef even in the central region. In this case, the focal position specifying unit 1041 can finely adjust the parameters of the eyeball model so that the light rays converge in the central region (the surface of the fundus Ef is the best image plane).

Next, the focal position specifying unit 1041 performs ray tracing processing on the peripheral region using the eyeball model whose parameters have been finely adjusted. That is, the focal position specifying unit 1041 tracks a light beam having an incident angle with respect to the measurement optical axis passing through the rotation point of the eye. The focal position specifying unit 1041 performs light ray tracing processing while changing the distance to the object point to obtain the distance to the object point at which the light ray converges at the fundus Ef in the peripheral region. The obtained distance to the object point corresponds to the distance point distance Lp in the peripheral region. The focal position specifying unit 1041 can obtain the refractive power SEp [diopter] of the peripheral region by using the following equation: SEp =-(1000 / Lp).

The focal position specifying unit 1041 obtains the refractive power SEp of the peripheral region corresponding to each of the plurality of incident angles by performing light ray tracing processing while changing the incident angle within a predetermined range. The refractive power of the peripheral region may be a discrete value for each incident angle, or may be a continuous value obtained by fitting with an arbitrary function in a predetermined range.

In this example, since the eyeball model is fine-tuned so that the light beam converges on the fundus Ef in the central region, the required refractive power of the peripheral region corresponds to the relative refractive power of the central region.

An example of the refractive power calculation process will be described. This example provides a method for obtaining the refractive power that reflects the shape of the fundus. In this example, as the shape of the fundus center region, a tilt angle of a predetermined layer region (for example, OS-RPE interface) of the fundus with respect to the horizontal direction (predetermined reference direction) is used.

In this example, the distance [mm] of the height data is acquired using the pixel spacing correction value [mm / pixel], and the height data is used to tilt the bottom surface of the eye θh for the B-scan image in the horizontal direction. Then, the tilt angle θv of the bottom surface of the eye is calculated for the B-scan image in the vertical direction. The tilt angles θh and θv can be calculated by the same method as the tilt angle g1 as described below.

FIG. 2E schematically shows a B-scan image in the horizontal direction. Reference numeral L1 is a vertical direction between the upper end UT of the frame at the left end LT of the frame of the B-scan image IMG and the image region corresponding to a predetermined layer region (for example, the OS-RPE interface or the nerve fiber layer) at the fundus Ef. Indicates the distance. The distance L1 is calculated from the height data at the left end LT of the frame. Similarly, reference numeral R1 indicates the vertical distance between the frame upper end UT and the image region corresponding to the same layer region at the frame right end RT of the B scan image IMG. The distance R1 is calculated from the height data at the right end RT of the frame.

The focal position specifying unit 1041 converts the difference (| R1-L1 |) in the vertical position of the image region at the left end LT of the frame and the right end RT of the frame in the B scan image IMG into the actual size | d |. Similarly, the focal position specifying unit 1041 converts the horizontal distance H1 of the frame of the B-scan image IMG into the actual size c. These conversion processes are executed using the pixel spacing correction value [mm / pixel].

The focal position specifying unit 1041 calculates the inclination angle g0 [degree] according to the following equation: g0 = arctan (| d | / c). The focal position specifying unit 1041 obtains the tilt angle of the fundus by correcting the inclination angle g0 according to the amount of deviation between the measurement optical axis and the eyeball optical axis.

When the measurement optical axis and the eyeball optical axis (visual axis) are substantially the same, the focal position specifying unit 1041 tilts the fundus of the eye without correcting the tilt angle g0 of the B scan image as shown in the following equation. Output as angle g1: g1 = g0 = arctan (| d | / c).

When the optical axis of the eyeball is shifted with respect to the optical axis of the measurement, the focal position specifying unit 1041 obtains the tilt angle g1 of the fundus surface by correcting the tilt angle g0 of the B scan image based on the shift amount.

For example, the focal position specifying unit 1041 obtains the correction angle φ1 according to a linear equation with the shift amount ds shown below as a variable: φ1 = α1 × ds + c1. Here, α1 and c1 are constants and are determined using, for example, model eye data. Further, the focal position specifying unit 1041 obtains the tilt angle g1 of the fundus by correcting the tilt angle g0 using the obtained correction angle φ1 as shown in the following equation: g1 = g0 − φ1.

When the optical axis of the eyeball is tilted with respect to the measurement optical axis, the focal position specifying unit 1041 obtains the tilt angle g1 of the fundus surface by correcting the tilt angle g0 of the B scan image based on the tilt amount.

For example, the focal position specifying unit 1041 obtains the correction angle φ2 according to a linear equation with the tilt amount dt as a variable as shown below: φ2 = α2 × dt + c2. Here, α2 and c2 are constants and are determined using, for example, model eye data. Further, the focal position specifying unit 1041 obtains the tilt angle g1 of the fundus by correcting the tilt angle g0 using the obtained correction angle φ2: g1 = g0 −φ2.

When the optical axis of the eyeball is shifted and tilted with respect to the measurement optical axis, the focal position specifying unit 1041 tilts the fundus surface by correcting the tilt angle g0 of the B scan image based on the shift amount and the tilt amount. Find the angle g1.

For example, when the shift amount ds and the tilt amount dt are sufficiently small, the focal position specifying unit 1041 obtains the correction angle φ3 according to the following equation with the shift amount ds and the tilt amount dt as variables: φ3 = α3. × ds + α4 × dt + c3. This equation is a linear combination of the equation for obtaining the correction angle of the shift amount and the equation for obtaining the correction angle of the tilt amount. Here, α3, α4 and c3 are constants and are determined using, for example, model eye data. Further, the focal position specifying unit 1041 obtains the tilt angle g1 of the fundus by correcting the tilt angle g0 using the obtained correction angle φ3 as shown in the following equation: g1 = g0 −φ3.

Next, the focal position specifying unit 1041 corrects the ring pattern image previously acquired by the reflex meter in the horizontal direction and the vertical direction according to the tilt angles θh and θv of the fundus, respectively. The focal position specifying unit 1041 can apply an elliptical approximation to the corrected ring pattern image, and obtain the refractive power from the obtained elliptical shape by a known method.

A fifth example of the peripheral refractive power calculation process will be described. This example provides a peripheral power calculation process to which the refractive power calculation process described with reference to FIG. 2E is applied.

Similar to the above example, the focal position specifying unit 1041 calculates the tilt angles θh and θv of the fundus of the eye from the B-scan image in the horizontal direction and the B-scan image in the vertical direction, respectively. Further, the focal position specifying unit 1041 is a ring acquired by a refractometer in a state where peripheral fixation is applied in the horizontal direction and the vertical direction according to the tilt angles θh and θv, respectively, as in the above example. Correct the pattern image. The focal position specifying unit 1041 applies an elliptical approximation to the corrected ring pattern image, and obtains the refractive power of the fundus peripheral region from the obtained elliptical shape by a known method.

The first to fifth examples described above are disclosed in Japanese Patent Application No. 2019-005431 by the applicant. In addition to these exemplary methods, for example, the method disclosed in Japanese Patent Application No. 2019-005434 by the present applicant and other methods for calculating the peripheral refractive power can be used. There are various other methods, one of which uses alignment information. This will be described later.

The focal position specifying unit 1041 calculates the refractive power corresponding to the peripheral portion of the fundus by any of these methods, and obtains the focal position of the virtual light beam incident on the peripheral portion of the fundus based on the calculated refractive power. The first evaluation execution unit 1042 executes the first evaluation based on the positional relationship between the focal position specified by the focal position specifying unit 1041 and the peripheral portion of the fundus.

The operation of the ophthalmic apparatus 1000 according to this aspect will be described. An example of the operation of the ophthalmic apparatus 1000 is shown in FIG. A storage device (not shown) of the ophthalmic apparatus 1000 stores software for realizing an operation example shown in FIG. The ophthalmic apparatus 1000 executes a series of processes shown in FIG. 3 by operating according to this software.

(S1: Remove the Ortho K lens from the eye)
First, remove the ortho-K lens to be evaluated from the eye.

(S2: Perform preparatory operations such as alignment)
Next, a predetermined preparatory operation for performing the detection and measurement described later is performed. The preparatory movement includes, for example, alignment of the ophthalmic apparatus 1000 with respect to the eye, focus adjustment, and the like. Further, when OCT is performed in any of the detection and measurement described later, the optical path length adjustment and the polarization adjustment are typically executed as preparatory operations. These preparatory operations are performed by a known method and configuration.

(S3: Measure the corneal shape of the eye)
The corneal shape measuring unit 1010 measures the corneal shape of the eye. The corneal shape data acquired thereby may typically be corneal curvature distribution data or corneal curvature radius distribution data.

(S4: Measure the fundus shape of the eye)
The fundus shape measuring unit 1020 measures the fundus shape of the eye. The fundus shape data acquired thereby may typically be OCT data generated by an OCT scan, fundus curvature distribution data or fundus curvature radius data based on the OCT data, or height data based on the OCT data.

(S5: Create an eyeball model)
The eyeball model creation unit 1030 creates an eyeball model based on at least the corneal shape data acquired in step S3 and the fundus shape data acquired in step S4. To create an eye model, in addition to corneal shape data and fundus shape data, known model eyes and measurement data of eye characteristics (typically, the refractive index of the central region, the refractive index of the peripheral region, the axial length, and the axial length, and , Eyeball parameter of any one or more of the anterior chamber depth), analysis data of the eye image, and the like may be used.

(S6: Perform evaluation)
The evaluation unit 1040 performs the first evaluation regarding the effect of the ortho-K lens on the eye, at least based on the eyeball model created in step S5.

The control unit 1050 can output, save, and record the result of the evaluation executed in step S6. For example, the control unit 1050 controls the display device to display the evaluation result, or controls the communication device to transmit the evaluation result to another device (for example, a medical information management device such as an electronic chart system). The evaluation result is stored in the storage device provided in the ophthalmic apparatus 1000, the evaluation result is printed on a paper medium by controlling the printer, and the evaluation result is written on the recording medium by controlling the drive device or the like. It is possible to make it.

The order of the steps shown in FIG. 3 can be arbitrarily changed. For example, corneal shape measurement can be performed before detection of a specific site.

<Second aspect>
The ophthalmic apparatus according to the second aspect will be described. FIG. 4 shows a configuration example of the ophthalmic apparatus according to this aspect. The ophthalmic apparatus 1500 includes a corneal shape measuring unit 1010, a fundus shape measuring unit 1020, an eyeball model creating unit 1030, an evaluation unit 1040, and a control unit 1050 similar to the ophthalmic apparatus 1000 according to the first aspect, as well as a specific site detection unit. Includes 1060 and a feature point setting unit 1070. Hereinafter, unless otherwise specified, the terms, symbols, etc. in the first aspect shall apply mutatis mutandis.

The specific site detection unit 1060 detects a specific site of the eye after removing the ortho-K lens. The specific site of the eye is typically the apex of the cornea or the center of the pupil, but may be other sites.

For the detection of the corneal apex, for example, as described above, a two-dimensional position or three-dimensional position detection method based on the Purkinje image, a two-dimensional position detection method based on the keratling image, and three-dimensional using the anterior segment OCT. Either the position detection method or any other detection method is applied.

For the detection of the center of the pupil, for example, a two-dimensional position detection method by analyzing the front image of the anterior segment, and a three-dimensional position detection method by analyzing two anterior segment images obtained by photographing from two directions. And any of the other detection methods is applied.

A typical specific site detection unit 1060 includes a photographing unit (optical system, image sensor, camera, etc.) that photographs the anterior eye portion, and a processor that analyzes an image obtained by the photographing unit. Further, the specific site detection unit 1060 may include a projection unit that projects a luminous flux for forming a Purkinje image or a keratling image. The processor operates according to, for example, analysis software (program) for detecting a specific part.

The feature point setting unit 1070 sets the feature point from the corneal shape data acquired by the corneal shape measurement unit 1010. The feature points represent characteristic positions in the shape of the cornea. The feature point is typically the aforementioned correction center. As described above, the correction center may be, for example, the apex of the cornea deformed by the ortho-K lens (corneal apex) or the center of the corneal shape deformed by the ortho-K lens (deformation center such as the fitting center). ..

A typical feature point setting unit 1070 includes a processor that analyzes corneal shape data to detect feature points. The processor operates according to analysis software (program) for setting feature points from corneal shape data. The analysis software includes, for example, software for detecting the corneal apex from the corneal shape data and software for detecting the deformation center from the corneal shape data. Software for detecting the deformation center from the corneal shape data includes, for example, a process of obtaining an approximate curved surface (fitting curved surface) or an approximate curve (fitting curve) of the corneal shape data, and a center of the approximate curved surface or the approximate curve (fitting center). It is configured to cause the processor to execute the process of requesting.

When the specific site detection unit 1060 specifies the corneal apex, the corneal shape measuring unit 1010 and the feature point setting unit 1070 set an arbitrary feature point (for example, a deformation center such as a fitting center) other than the corneal apex. Can be done. On the other hand, when the specific site detection unit 1060 specifies an eye region other than the corneal apex (for example, the center of the pupil), the corneal shape measuring unit 1010 and the feature point setting unit 1070 may use an arbitrary correction center (for example, the corneal apex or the center of the pupil). The center of deformation) can be set as the feature point.

The evaluation unit 1040 of this aspect is configured to perform the following second evaluation in addition to the first evaluation (evaluation of the effect of the ortho-K lens on the eye based on at least the eyeball model) similar to the first aspect. Will be done.

In the second evaluation, the evaluation unit 1040 evaluates the wearing state of the ortho-K lens with respect to the eye based on the specific part detected by the specific part detection unit 1060 and the feature point set by the feature point setting unit 1070. Run. The evaluation unit 1040 evaluates, for example, based on the deviation (positional deviation) between the specific portion and the feature point.

For example, when the specific site detection unit 1060 detects the corneal apex as a specific site and the feature point setting unit 1070 fits the corneal shape data, the evaluation unit 1040 determines the corneal apex detected by the specific site detection unit 1060. The evaluation is performed based on the deviation between the image and the fitting center set by the feature point setting unit 1070.

In another example, when the specific site detection unit 1060 detects the center of the pupil as a specific site and the feature point setting unit 1070 fits the corneal shape data, the evaluation unit 1040 is detected by the specific site detection unit 1060. The evaluation is performed based on the deviation between the center of the pupil and the center of fitting set by the feature point setting unit 1070.

When both the specific part and the feature point represent the three-dimensional position, the evaluation unit 1040 evaluates by comparing these two three-dimensional positions. Similarly, when both the specific part and the feature point represent a two-dimensional position, the evaluation unit 1040 evaluates by comparing these two two-dimensional positions. On the other hand, when one of the specific part and the feature point represents the two-dimensional position and the other represents the three-dimensional position, the evaluation unit 1040 typically has the latter in the two-dimensional coordinate system representing the former two-dimensional position. The two can be compared by projecting the three-dimensional position.

A typical evaluation unit 1040 includes a processor that evaluates the wearing state of the Ortho K lens based on a specific part and a feature point. The processor operates according to the evaluation software (program) for performing the evaluation. The analysis software includes, for example, software for calculating the deviation between a specific part and a feature point, and software for performing evaluation based on the calculated deviation and a predetermined evaluation standard (evaluation protocol). ..

The operation of the ophthalmic apparatus 1500 according to this aspect will be described. An example of the operation of the ophthalmic apparatus 1500 is shown in FIG. Software for realizing the operation example shown in FIG. 5 is stored in a storage device (not shown) of the ophthalmic apparatus 1500. The ophthalmic apparatus 1500 executes a series of processes shown in FIG. 5 by operating according to this software.

(S11: Remove the Ortho K lens from the eye)
First, remove the ortho-K lens to be evaluated from the eye.

(S12: Performs preparatory operations such as alignment)
Next, a predetermined preparatory operation is performed in the same manner as in step S2 of the first aspect.

(S13: Detects a specific part of the eye)
The specific site detection unit 1060 detects a specific site of the eye. A particular part of the eye is typically the apex of the cornea or the center of the pupil. As a result, the position data of a specific part of the eye can be obtained.

(S14: Measure the corneal shape of the eye)
In the same manner as in step S3 of the first aspect, the corneal shape measuring unit 1010 measures the corneal shape of the eye and acquires the corneal shape data.

(S15: Set feature points from corneal shape data)
The feature point setting unit 1070 sets the feature point from the corneal shape data acquired in step S14. The feature points represent characteristic positions in the shape of the cornea and are typically the center of correction. The orthodontic center is typically the apex of the cornea or the center of deformation (fitting center, etc.).

(S16: Perform the second evaluation)
The evaluation unit 1040 is based on the specific site detected in step S13 and the feature point set in step S15 (for example, based on the deviation between the specific site and the feature point), and the ortho-K with respect to the eye. The evaluation of the attached state of the lens (second evaluation) is executed.

(S17: Measure the fundus shape of the eye)
In the same manner as in step S4 of the first aspect, the fundus shape measuring unit 1020 measures the fundus shape of the eye and acquires the fundus shape data.

(S18: Create an eyeball model)
In the same manner as in step S5 of the first aspect, the eyeball model creating unit 1030 creates an eyeball model based on at least the corneal shape data acquired in step S14 and the fundus shape data acquired in step S17. ..

(S19: Perform the first evaluation)
In the same manner as in step S6 of the first aspect, the evaluation unit 1040 performs the first evaluation regarding the effect of the ortho-K lens on the eye, at least based on the eyeball model created in step S18.

In the first evaluation of this aspect, the result of the second evaluation performed in step S16 or the information for obtaining the result can be referred to. For example, the central part of the fundus is set with reference to the correction center (for example, the apex of the cornea, the center of the pupil, or the center of fitting) set in step S15, and the part around the center is set as the peripheral part of the fundus. The first evaluation can be performed.

In this way, the peripheral portion of the fundus to be evaluated changes according to the correction center (corneal apex, pupil center, fitting center, etc.) required for the second evaluation. In addition, considering that the surface shape of the retina is generally asymmetric, the peripheral refractive power obtained in the first evaluation is also a value calculated according to where the fundus center (analysis center, evaluation center) is set. The evaluation result based on it changes. In this example, it is possible to analyze by associating the center of the cornea (center of the anterior segment of the eye) with the center of the fundus (center of the retina) while considering both the corneal shape and the retinal shape (fundus shape). Therefore, it can be said that it is excellent in the accuracy and reproducibility of the inspection.

The evaluation unit 1040 can perform a comprehensive evaluation based on the result of the second evaluation obtained in step S16 and the result of the first evaluation obtained in step S19.

For example, when the results of both the second evaluation and the first evaluation are "OK", that is, in the second evaluation, it is evaluated that the wearing state of the ortho-K lens with respect to the eye is suitable, and the first evaluation When it is evaluated that the desired effect of suppressing the progression of myopia is obtained, for example, it can be proposed to continue using the ortho-K lens.

If the result of both the second evaluation and the first evaluation is "NG", for example, it has a shape and size that fits the eye better (that is, it has a shape and / or size different from the current one). ), And it can be proposed to change to an ortho-K lens having a peripheral refractive index different from the current one. That is, it is possible to propose a review of the prescription of the Ortho K lens for the eye.

When the result of the first evaluation is "NG" and the result of the second evaluation is "OK", for example, the periphery has the same shape and size as the current one and is different from the current one. It can be proposed to change to an ortho-K lens with a degree of refraction.

When the result of the first evaluation is "OK" and the result of the second evaluation is "NG", for example, it has a shape and size that fits the eye better (that is, different from the current one). It can be proposed to change to an ortho-K lens that has the same shape and / or size) and has the same peripheral refraction as the current one.

It should be noted that the prescription of the Ortho K lens has been reviewed in the past, and when this time is the second time or later, it is conceivable that the result of at least one of the second evaluation and the first evaluation is "NG". For example, if the ortho-K lens adopted in the previous review of the prescription does not fit the cornea of the eye, or if it is determined that there is no ortho-K lens that can correct the refractive state of the peripheral part due to the progress of fundus tilt. , It can be determined that orthokeratology is not applicable, and other treatment methods can be proposed.

The control unit 1050 can output, store, and record the result of the second evaluation obtained in step S16. Further, the control unit 1050 can output, save, and record the evaluation result obtained in step S19. Further, the control unit 1050 can output, store, and record the result of the comprehensive evaluation based on both the second evaluation and the first evaluation.

The order of the steps shown in FIG. 5 can be arbitrarily changed. For example, corneal shape measurement can be performed before detection of a specific site.

<Third aspect>
The ophthalmic apparatus according to the third aspect will be described. This aspect is applied when the ortho-K lens is prescribed based on the corneal apex of the eye, and the ortho-K lens formulation (lens type) and its mounting based on the position of the ortho-K lens with respect to the corneal apex and the shape of the fundus. Evaluate whether the position is appropriate. In this embodiment, when the ortho-K lens is properly attached with reference to the corneal apex of the eye, the corneal apex after removing the ortho-K lens should coincide with the deformation center (fitting center, etc.). Assuming. Further, in this aspect, it is assumed that the eye has no astigmatism and that the shape (aspherical surface) of the cornea deformed by the ortho-K lens is isotropic. Here, the absence of astigmatism in the eye means that, for example, the measured value of the degree of astigmatism in the eye is equal to or less than a predetermined threshold value, and this embodiment can be applied to such an eye.

FIG. 6 shows a configuration example of the ophthalmic apparatus according to this aspect. The ophthalmic apparatus 2000 has an eye characteristic measurement function and an OCT function.

Examples of measurable eye characteristics are refractive power and corneal shape. Examples of refractive power parameters include spherical power, astigmatic power, and astigmatic axis angle. Examples of corneal shape parameters include corneal curvature and radius of curvature of the cornea. The corneal shape is typically represented by a corneal curvature distribution or a corneal radius of curvature distribution. In general, the curvature and the radius of curvature are inversely related to each other, and the corneal curvature and the radius of curvature of the cornea are equivalent parameters.

The type of OCT applicable to this embodiment is arbitrary. Swept source OCT is applied in this embodiment, but it may be spectral domain OCT or other type.

The ophthalmic apparatus may have other objective measurement functions and may also have a subjective examination function. The subjective test is a measurement method for acquiring information by using the response from the subject, and is typically a subjective refraction measurement such as a distance test, a near test, a contrast test, a glare test, or a visual field test. and so on. Objective measurement is a measurement method in which eye data is acquired mainly by using a physical method without referring to a response from a subject. Objective measurement includes measurement for acquiring eye characteristic data and imaging for acquiring eye image data. In addition to the above-mentioned refractive power measurement and corneal shape measurement, the objective measurement includes intraocular pressure measurement, anterior ocular segment imaging, fundus photography, OCT and the like.

In this embodiment, unless otherwise specified, the conjugate relationship between the eye site and the position in the optical system means the mutual positional relationship in a state where alignment is preferable. For example, the fundus conjugate position in the optical system is a position that is optically conjugate with the fundus in a state where alignment is preferable, and means a position that is optically conjugate with the fundus or its vicinity. Further, the pupil conjugate position is a position optically conjugate with the pupil in a state where alignment is preferable, and means a position optically conjugate with the pupil or its vicinity.

Hereinafter, the direction along the optical axis of the optical system of the ophthalmic apparatus 2000 is referred to as the Z direction. Further, the first coordinate axis (for example, the coordinate axis along the horizontal direction) and the second coordinate axis (for example, the vertical direction) of the two-dimensional Cartesian coordinate system (XY coordinate system) that defines the plane (XY plane) orthogonal to the optical axis (Z coordinate axis). The direction along the first coordinate axis (X coordinate axis) is called the X direction, and the direction along the second coordinate axis (Y coordinate axis) is called the Y direction.

The ophthalmic apparatus 2000 shown in FIG. 6 includes a Z alignment system 1, an XY alignment system 2, a kerato measurement system 3, a fixation projection system 4, an anterior segment observation system 5, a reflex measurement projection system 6, and a reflex measurement light receiving system 7. , And the OCT optical system 8. In the following, for example, the anterior segment observation system 5 uses light of 940 nm to 1000 nm, and the ref measurement optical system (ref measurement projection system 6, reflex measurement light receiving system 7) uses light of 830 nm to 880 nm, and the fixation projection system. It is assumed that 4 uses light of 400 nm to 700 nm, and OCT optical system 8 uses light of 1000 nm to 1100 nm.

The anterior segment observation system 5 captures a moving image of the anterior segment of the eye E. In the optical system passing through the anterior segment observation system 5, the image pickup surface of the image pickup device 59 is arranged at the pupil conjugate position. The anterior segment illumination light source 50 irradiates the anterior segment of the eye E with illumination light (for example, infrared light). The light reflected by the anterior segment of the eye E passes through the objective lens 51, passes through the dichroic mirror 52, passes through the hole formed in the diaphragm (teresen diaphragm) 53, and passes through the half mirror 23. It passes through the relay lenses 55 and 56 and passes through the dichroic mirror 76. The dichroic mirror 52 connects the optical path of the reflex measurement optical system and the optical path of the anterior segment observation system 5. In the dichroic mirror 52, the optical path coupling surface to which these optical paths are coupled is arranged so as to be inclined with respect to the optical axis of the objective lens 51. The light transmitted through the dichroic mirror 76 is imaged on the image pickup surface of the image pickup element 59 (area sensor) by the image pickup lens 58. The image sensor 59 performs image pickup and signal output at a predetermined rate. The output (video signal) of the image sensor 59 is input to the computer 9 described later. The computer 9 displays the anterior segment image E'based on this video signal on the display screen 10a of the display unit 10. The anterior segment image E'is, for example, an infrared moving image.

The Z alignment system 1 projects light (infrared light) for alignment in the optical axis direction (front-back direction, Z direction) of the anterior segment observation system 5 onto the eye E. The light output from the Z-alignment light source 11 is obliquely projected onto the cornea Cr of the eye E, reflected by the cornea Cr, and imaged on the sensor surface of the line sensor 13 by the imaging lens 12.

When the position of the corneal Cr (corneal apex) changes in the Z direction, the light projection position on the sensor surface of the line sensor 13 changes. The computer 9 obtains the position of the corneal apex of the eye E based on the projection position of light on the sensor surface of the line sensor 13, and controls the mechanism for moving the optical system based on this to execute Z alignment. This Z alignment method is an example of an alignment method using an optical lever.

Any one-dimensional or two-dimensional image sensor can be used instead of the line sensor 13. That is, the photodetector provided in the Z alignment system may be an arbitrary image sensor in which a plurality of photodetectors (photodiodes, etc.) are arranged one-dimensionally or two-dimensionally.

The XY alignment system 2 provides the eye E with a luminous flux (infrared light) for aligning in a direction (horizontal direction (X direction), vertical direction (Y direction)) orthogonal to the optical axis of the anterior segment observation system 5. Irradiate. The XY alignment system 2 includes an XY alignment light source 21 and a collimator lens 22 provided in an optical path branched from the optical path of the anterior segment observation system 5 by a half mirror 23. The light output from the XY alignment light source 21 passes through the collimator lens 22, is reflected by the half mirror 23, and is projected onto the eye E through the anterior segment observation system 5. The reflected light from the corneal Cr of the eye E is guided to the image sensor 59 through the anterior segment observation system 5.

The image (bright spot image) Br based on this reflected light is included in the anterior segment image E'. The computer 9 displays the anterior segment image E'including the bright spot image Br and the alignment mark AL on the display screen 10a of the display unit 10. When the XY alignment is manually performed, the user operates the optical system so as to guide the bright spot image Br in the alignment mark AL. When the alignment is performed automatically, the computer 9 controls a mechanism for moving the optical system so that the deviation of the bright spot image Br with respect to the alignment mark AL is cancelled.

The kerato measurement system 3 projects a ring-shaped luminous flux (infrared light) for measuring the shape of the corneal Cr of the eye E onto the cornea Cr. The kerato plate 31 is arranged between the objective lens 51 and the eye E. A keratling light source 32 is provided on the back side (objective lens 51 side) of the kerato plate 31. By illuminating the kerato plate 31 with the light from the kerat ring light source 32, a ring-shaped luminous flux (arc-shaped or circumferential-shaped measurement pattern) is projected onto the corneal Cr of the eye E. The reflected light (keratling image) from the corneal Cr of the eye E is detected by the image sensor 59 together with the anterior segment image E'. The computer 9 calculates the value of the corneal shape parameter representing the shape of the corneal Cr by performing a known calculation based on this keratling image. A typical corneal shape parameter is the radius of curvature of the cornea (corneal curvature).

In addition, instead of or in addition to the kerato measurement system 3, the ophthalmic apparatus 2000 may include a corneal topography system (corneal topography system). The corneal topography system includes a group of elements for obtaining the above-mentioned corneal topography (see, for example, Japanese Patent Application Laid-Open No. 8-280624). The corneal topography system projects a multiple concentric pattern called platidling onto the corneal Cr. The reflected light (platidling image) from the corneal Cr is detected by the image sensor 59 together with the anterior segment image E'. The computer 9 obtains the distribution of the corneal shape parameters representing the shape of the corneal Cr by performing a known calculation based on this platidling image. The corneal topogram is provided by expressing the obtained distribution data in pseudo color.

The reflex measurement optical system includes a reflex measurement projection system 6 and a reflex measurement light receiving system 7 used for refraction force measurement. The reflex measurement projection system 6 projects a luminous flux for measuring the refractive power (for example, a ring-shaped luminous flux) onto the fundus Ef. This luminous flux is typically infrared light. The reflex measurement light receiving system 7 detects the return light of this luminous flux from the eye E. The reflex measurement projection system 6 is provided in an optical path branched by a perforated prism 65 provided in the optical path of the reflex measurement light receiving system 7. The hole formed in the perforated prism 65 is arranged at the pupil conjugate position. In the optical system passing through the reflex measurement light receiving system 7, the image pickup surface of the image pickup device 59 is arranged at the fundus conjugate position.

In this embodiment, the ref measurement light source 61 may be, for example, a superluminescent diode (SLD) which is a high-luminance light source. The reflex measurement light source 61 is movable in the optical axis direction. The reflex measurement light source 61 is arranged at the fundus conjugate position. The light output from the reflex measurement light source 61 passes through the relay lens 62 and is incident on the conical surface of the conical prism 63. The light incident on the conical surface is deflected and emitted from the bottom surface of the conical prism 63. The light emitted from the bottom surface of the conical prism 63 passes through the translucent portion formed in a ring shape on the ring diaphragm 64. The light (ring-shaped luminous flux) that has passed through the translucent portion of the ring diaphragm 64 is reflected by the reflecting surface formed around the hole portion of the perforated prism 65, passes through the rotary prism 66, and is reflected by the dichroic mirror 67. To. The light reflected by the dichroic mirror 67 is reflected by the dichroic mirror 52, passes through the objective lens 51, and is projected onto the eye E. The rotary prism 66 is used for averaging the light amount distribution of the ring-shaped luminous flux with respect to the blood vessels and diseased parts of the fundus Ef and reducing speckle noise caused by the light source.

The return light of the ring-shaped luminous flux projected on the fundus Ef passes through the objective lens 51 and is reflected by the dichroic mirror 52 and the dichroic mirror 67. The return light reflected by the dichroic mirror 67 passes through the rotary prism 66, passes through the hole portion of the perforated prism 65, passes through the relay lens 71, is reflected by the reflection mirror 72, and is reflected by the relay lens 73 and the focusing lens. Pass through 74. The focusing lens 74 can move along the optical axis of the reflex measurement light receiving system 7. The light that has passed through the focusing lens 74 is reflected by the reflection mirror 75, reflected by the dichroic mirror 76, and imaged on the image pickup surface of the image pickup element 59 by the image pickup lens 58. The computer 9 calculates the refractive power value of the eye E by performing a known calculation based on the output from the image sensor 59. For example, the power value includes at least one of spherical power, astigmatic power and astigmatic axis angle, and equivalent spherical power.

The OCT optical system 8 is provided in an optical path whose wavelength is separated from the optical path of the ref measurement optical system by the dichroic mirror 67. The fixation projection system 4 is provided in the optical path branched from the optical path of the OCT optical system 8 by the dichroic mirror 83.

The fixation projection system 4 presents the fixation target to the eye E. The fixation unit 40 is arranged in the optical path of the fixation projection system 4. The fixation unit 40 is controlled by a computer 9 described later, and can move along the optical path of the fixation projection system 4. The fixation unit 40 includes a liquid crystal panel 41.

The liquid crystal panel 41 controlled by the computer 9 displays a pattern representing the fixation target. By changing the display position of the pattern on the screen of the liquid crystal panel 41, the fixation position of the eye E can be changed. The fixation position is centered on the position for acquiring an image centered on the macula, the position for acquiring an image centered on the optic nerve head, and the center of the fundus between the macula and the optic nerve head. There is a position to acquire the image to be used. It is possible to arbitrarily change the display position of the pattern representing the fixation target. Instead of the liquid crystal panel 41, a transmissive optotype chart on which an optotype or the like is printed on a film or the like and an illumination light source for illuminating the optotype chart may be provided.

The light from the liquid crystal panel 41 passes through the relay lens 42, passes through the dichroic mirror 83, passes through the relay lens 82, is reflected by the reflection mirror 81, passes through the dichroic mirror 67, and is reflected by the dichroic mirror 52. .. The light reflected by the dichroic mirror 52 passes through the objective lens 51 and is projected onto the fundus Ef. In some embodiments, the liquid crystal panel 41 and the relay lens 42 are independently movable in the optical axis direction.

The OCT optical system 8 is an optical system for applying OCT to the eye E. The position of the focusing lens 87 is adjusted so that the end face of the optical fiber f1 is conjugate with the imaging site (fundus Ef or anterior segment) based on the result of the reflex measurement performed before the OCT.

The OCT optical system 8 is provided in an optical path whose wavelength is separated from the optical path of the ref measurement optical system by a dichroic mirror 67. The optical path of the fixation projection system 4 is coupled to the optical path of the OCT optical system 8 by the dichroic mirror 83. As a result, the optical axes of the OCT optical system 8 and the fixation projection system 4 can be coaxially coupled.

The OCT optical system 8 includes an OCT unit 100. As shown in FIG. 7, in the OCT unit 100, the OCT light source 101 includes a tunable light source capable of sweeping the wavelength of the emitted light, similar to a general swept source type OCT device. The tunable light source includes a laser light source including a resonator. The OCT light source 101 changes the output wavelength with time in a near-infrared wavelength band that is invisible to the human eye. The OCT light source 101 includes, for example, a near-infrared wavelength tunable laser that changes the wavelength of emitted light (wavelength range of 1000 nm to 1100 nm) at high speed.

As illustrated in FIG. 7, the OCT unit 100 is provided with an optical system for performing a swept source OCT. This optical system includes an interference optical system. This interference optical system has a function of dividing the light from the variable wavelength light source into the measurement light and the reference light, and superimposes the return light of the measurement light from the eye E and the reference light passing through the reference optical path to generate the interference light. It has a function to generate and a function to detect this interference light. The detection result (detection signal) of the interference light obtained by the interference optical system is a signal representing the spectrum of the interference light and is sent to the computer 9. Further, at least one of the length of the optical path (measurement arm, sample arm) of the measurement light and the length of the optical path (reference arm) of the reference light are variable.

The light L0 output from the OCT light source 101 is guided by the optical fiber 102 to the polarization controller 103, and its polarization state is adjusted. The light L0 whose polarization state is adjusted is guided by the optical fiber 104 to the fiber coupler 105 and divided into the measurement light LS and the reference light LR.

The reference light LR is guided by the optical fiber 110 to the collimator 111, converted into a parallel luminous flux, and guided to the corner cube 114 via the optical path length correction member 112 and the dispersion compensation member 113. The optical path length correction member 112 acts to match the optical path length of the reference light LR with the optical path length of the measurement light LS. The dispersion compensating member 113 acts to match the dispersion characteristics between the reference light LR and the measurement light LS. The corner cube 114 is movable in the incident direction of the reference light LR, thereby changing the optical path length of the reference light LR.

The reference light LR that has passed through the corner cube 114 is converted from a parallel luminous flux to a focused luminous flux by the collimator 116 via the dispersion compensating member 113 and the optical path length correction member 112, and is incident on the optical fiber 117. The reference light LR incident on the optical fiber 117 is guided by the polarization controller 118 to adjust its polarization state, is guided to the attenuator 120 by the optical fiber 119 to adjust the amount of light, and is guided to the fiber coupler 122 by the optical fiber 121.

On the other hand, the measurement light LS generated by the fiber coupler 105 is guided by the optical fiber f1 and converted into a parallel light beam by the collimator lens unit 89, and passes through the optical scanner 88, the focusing lens 87, the relay lens 85, and the reflection mirror 84. Then, it is reflected by the dichroic mirror 83.

The optical scanner 88 deflects the measurement light LS one-dimensionally or two-dimensionally. The optical scanner 88 includes, for example, a first galvano mirror and a second galvano mirror. The first galvanometer mirror deflects the measurement light LS so as to scan the imaging region (fundus Ef or anterior segment) in the horizontal direction (X direction) orthogonal to the optical axis of the OCT optical system 8. The second galvano mirror deflects the measurement light LS deflected by the first galvano mirror so as to scan the imaging portion in the vertical direction (Y direction) orthogonal to the optical axis of the OCT optical system 8. Examples of the scan pattern of the measured optical LS by the optical scanner 88 include horizontal scan, vertical scan, cross scan, radial scan, circular scan, concentric circular scan, and spiral scan.

The measurement light LS reflected by the dichroic mirror 83 passes through the relay lens 82, is reflected by the reflection mirror 81, is transmitted through the dichroic mirror 67, is reflected by the dichroic mirror 52, is refracted by the objective lens 51, and is refracted by the objective lens 51 to the eye E. Incident. The measurement light LS is scattered and reflected at various depth positions of the eye E. The return light of the measurement light LS from the eye E travels in the same direction as the outward path in the opposite direction, is guided to the fiber coupler 105, and reaches the fiber coupler 122 via the optical fiber 128.

The fiber coupler 122 superimposes the measurement light LS incidented through the optical fiber 128 and the reference light LR incidented through the optical fiber 121 to generate interference light. The fiber coupler 122 generates a pair of interference light LCs by branching the interference light at a predetermined branching ratio (for example, 1: 1). The pair of interference light LCs are guided to the detector 125 through optical fibers 123 and 124, respectively.

The detector 125 is, for example, a balanced photodiode. The balanced photodiode includes a pair of photodetectors that detect each pair of interference light LCs, and outputs the difference between the pair of detection results obtained by these photodetectors. The detector 125 sends this output (detection signal) to the data acquisition system (DAQ) 130.

A clock KC is supplied to the DAQ 130 from the OCT light source 101. The clock KC is generated in the OCT light source 101 in synchronization with the output timing of each wavelength swept within a predetermined wavelength range by the tunable light source. The OCT light source 101 optically delays one of the two branched lights obtained by branching the light L0 of each output wavelength, and then sets the clock KC based on the result of detecting the combined light. Generate. The DATA 130 samples the detection signal input from the detector 125 based on the clock KC. The DATA 130 sends the sampling result of the detection signal from the detector 125 to the computer 9. The computer 9 forms a reflection intensity profile in each A line by, for example, performing a Fourier transform or the like on the spectral distribution based on the sampling data for each series of wavelength sweeps (for each A line). Further, the computer 9 forms image data by imaging the reflection intensity profile of each A line.

In this example, an element (movable corner cube 114) for changing the reference arm length is provided in order to change the difference between the measurement arm length and the reference arm length to move the coherence gate. Elements may be adopted. For example, a movable mirror can be provided on the reference arm, or a retroreflector such as a movable corner cube can be provided on the measuring arm.

The computer 9 calculates the refractive power value from the measurement result obtained by using the reflex measurement optical system, and based on the calculated refraction power value, the fundus Ef, the reflex measurement light source 61, and the image sensor 59 are conjugated. The refraction measurement light source 61 and the focusing lens 74 are moved to the positions in the optical axis direction. In some embodiments, the computer 9 moves the focusing lens 87 of the OCT optical system 8 in the optical axis direction in conjunction with the movement of the focusing lens 74. In some embodiments, the computer 9 moves the liquid crystal panel 41 (fixation unit 40) in the optical axis direction in conjunction with the movement of the reflex measurement light source 61 and the focusing lens 74. In addition to these, the computer 9 executes various controls, various data processes, various calculations, and the like.

The configuration of the processing system of the ophthalmic apparatus 2000 will be described. Examples of the functional configuration of the processing system of the ophthalmic apparatus 2000 are shown in FIGS. 8 and 9. FIG. 8 shows a functional block diagram of an example of the processing system of the ophthalmic apparatus 2000. FIG. 9 shows a functional block diagram of an example of the data processing unit 223.

The computer 9 controls each part of the ophthalmic apparatus 2000, performs various data processing, performs various calculations, and the like. The computer 9 includes one or more processors and one or more storage devices. The storage device includes, for example, a hard disk drive, RAM, ROM, semiconductor memory, and the like.

Various programs (software) such as one or more control programs, one or more data processing programs, and one or more arithmetic programs are stored in the storage device. When either processor operates according to any program, the computer 9 executes control, data processing, calculation, and the like. That is, the computer 9 executes control, data processing, calculation, and the like in collaboration with hardware such as a processor and software.

The computer 9 includes a control unit 210 and an arithmetic processing unit 220. Further, the ophthalmic apparatus 2000 includes a moving mechanism 200, a display unit 270, an operation unit 280, and a communication unit 290.

The moving mechanism 200 is a mechanism for moving the head portion of the ophthalmic apparatus 2000 in the front-back and left-right directions. The head includes a Z alignment system 1, an XY alignment system 2, a kerato measurement system 3, a fixation projection system 4, an anterior segment observation system 5, a reflex measurement projection system 6, a reflex measurement light receiving system 7, and an OCT optical system. 8 (at least an element group excluding the OCT unit 100) and the like are housed. For example, the moving mechanism 200 is provided with an actuator that generates a driving force for moving the head portion and a transmission mechanism that transmits the driving force. The actuator is composed of, for example, a pulse motor. The transmission mechanism is composed of, for example, a combination of gears and a rack and pinion. The control unit 210 (main control unit 211) controls the moving mechanism 200 by sending a control signal to the actuator.

The control unit 210 includes one or more processors and controls each unit of the ophthalmic apparatus 2000. The control unit 210 includes a main control unit 211 and a storage unit 212. A group of programs for controlling the ophthalmic apparatus 2000 is stored in the storage unit 212 in advance. The program group includes a light source control program, a detector control program, an optical scanner control program, an optical system control program, an alignment control program, an arithmetic processing program, a user interface program, and the like. The ophthalmic apparatus 2000 executes calculations and controls according to such a program.

The main control unit 211 performs various controls of the ophthalmic apparatus 2000. The control for the Z alignment system 1 includes the control of the Z alignment light source 11 and the control of the line sensor 13. The control of the Z alignment light source 11 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. The control of the line sensor 13 includes exposure adjustment, gain adjustment, and detection rate adjustment of the detection element. As a result, the Z alignment light source 11 is switched between lighting and non-lighting, and the amount of light is changed. The main control unit 211 captures the signal detected by the line sensor 13 and specifies the projection position of the light with respect to the line sensor 13 based on the captured signal. The main control unit 211 obtains the position of the corneal apex of the eye E based on the specified projection position, and controls the movement mechanism 200 based on this to move the head unit in the front-rear direction (Z alignment).

The control for the XY alignment system 2 includes the control of the XY alignment light source 21. The control of the XY alignment light source 21 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. As a result, the XY alignment light source 21 is switched between lighting and non-lighting, and the amount of light is changed. The main control unit 211 captures the signal detected by the image sensor 59, and determines the position of the bright spot image based on the return light of the light from the XY alignment light source 21 based on the captured signal. The main control unit 211 controls the movement mechanism 200 so as to cancel the deviation of the bright spot image Br with respect to a predetermined target position (for example, the center position of the alignment mark AL) to move the head unit in the left-right, up-down direction. (XY alignment).

The control for the kerato measurement system 3 includes the control of the kerat ring light source 32 and the like. Control of the keratling light source 32 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. As a result, the keratling light source 32 is switched between lighting and non-lighting, and the amount of light is changed. The main control unit 211 causes the arithmetic processing unit 220 to perform a known calculation on the keratling image detected by the image sensor 59. As a result, the value of the corneal shape parameter of the eye E is obtained. Even when the above-mentioned corneal topography system is provided, the main control unit 211 executes the same process.

Controls for the fixation projection system 4 include control of the liquid crystal panel 41 and movement control of the fixation unit 40. The control of the liquid crystal panel 41 includes turning on / off the display of the fixation target, switching the display position of the fixation target, and the like.

For example, the fixation projection system 4 is provided with a moving mechanism for moving the liquid crystal panel 41 (or fixation unit 40) in the optical axis direction. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and at least moves the liquid crystal panel 41 in the optical axis direction. As a result, the position of the liquid crystal panel 41 is adjusted so that the liquid crystal panel 41 and the fundus Ef are optically conjugated.

Controls for the anterior segment observation system 5 include control of the anterior segment illumination light source 50, control of the image pickup element 59, and the like. Control of the anterior segment illumination light source 50 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. As a result, the lighting of the anterior segment illumination light source 50 can be switched between lighting and non-lighting, and the amount of light can be changed. Control of the image sensor 59 includes exposure adjustment, gain adjustment, and detection rate adjustment of the image sensor 59. The main control unit 211 captures the signal detected by the image sensor 59, and causes the arithmetic processing unit 220 to perform processing such as forming an image based on the captured signal.

The control for the reflex measurement projection system 6 includes the control of the reflex measurement light source 61, the control of the rotary prism 66, and the like. The control of the reflex measurement light source 61 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. As a result, the reflex measurement light source 61 can be switched between lighting and non-lighting, and the amount of light can be changed. For example, the reflex measurement projection system 6 includes a moving mechanism that moves the reflex measurement light source 61 in the optical axis direction. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and moves the ref measurement light source 61 in the optical axis direction. Control of the rotary prism 66 includes rotation control of the rotary prism 66 and the like. For example, a rotation mechanism for rotating the rotary prism 66 is provided, and the main control unit 211 rotates the rotary prism 66 by controlling the rotation mechanism.

Control of the reflex measurement light receiving system 7 includes control of the focusing lens 74 and the like. Control of the focusing lens 74 includes control of movement of the focusing lens 74 in the optical axis direction. For example, the reflex measurement light receiving system 7 includes a moving mechanism for moving the focusing lens 74 in the optical axis direction. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and moves the focusing lens 74 in the optical axis direction. The main control unit 211 sets the optical axis of the reflex measurement light source 61 and the focusing lens 74 according to, for example, the refractive power of the eye E so that the reflex measurement light source 61, the fundus Ef, and the image sensor 59 are optically coupled. It is possible to move in the direction.

The control for the OCT optical system 8 includes the control of the OCT light source 101, the control of the optical scanner 88, the control of the focusing lens 87, the control of the corner cube 114, the control of the detector 125, the control of the DAQ 130, and the like. Control of the OCT light source 101 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. The control of the optical scanner 88 includes control of the scan position, scan range, and scan speed by the first galvanometer mirror, control of the scan position, scan range, and scan speed by the second galvanometer mirror.

The control of the focusing lens 87 includes control of movement of the focusing lens 87 in the optical axis direction, control of movement of the focusing lens 87 to the focusing reference position corresponding to the imaging region, and movement range corresponding to the imaging region (focusing). There is movement control within the focal range). For example, the OCT optical system 8 includes a moving mechanism that moves the focusing lens 87 in the optical axis direction. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and moves the focusing lens 87 in the optical axis direction. In some embodiments, the ophthalmic apparatus 2000 is provided with a holding member that holds the focusing lenses 74 and 87 and a driving unit that drives the holding member. The main control unit 211 controls the movement of the focusing lenses 74 and 87 by controlling the drive unit. For example, the main control unit 211 may move the focusing lens 87 in conjunction with the movement of the focusing lens 74, and then move only the focusing lens 87 based on the intensity of the interference signal.

Control of the corner cube 114 includes movement control along the optical path of the corner cube 114. For example, the OCT optical system 8 includes a moving mechanism that moves the corner cube 114 in a direction along an optical path. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the corner cube 114 and a transmission mechanism that transmits the driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and moves the corner cube 114 in the direction along the optical path. Control of the detector 125 includes exposure adjustment, gain adjustment, and detection rate adjustment of the detection element. The main control unit 211 causes the DAQ 130 to sample the signal detected by the detector 125, and causes the arithmetic processing unit 220 (image forming unit 222) to perform processing such as image construction based on the sampled signal.

Further, the main control unit 211 includes a measured value of the refractive power calculated by the eye refractive power calculation unit 221, a tomographic image (OCT image) formed by the image forming unit 222, and a result obtained by the data processing unit 223 described later. The information corresponding to the above is displayed on the display unit 270.

The storage unit 212 stores various types of data. As an example of the data stored in the storage unit 212, the data obtained by objective measurement, the data obtained by OCT scan, the image data of the tomographic image, the image data of the anterior segment image, and the data processed unit 230 are supplied. Data, data generated by the data processing unit 230, eye test information, and the like. The eye test information includes information related to the test eye such as left eye / right eye identification information.

The arithmetic processing unit 220 includes an eye refractive power calculation unit 221, an image forming unit 222, and a data processing unit 223.

The eye refractive power calculation unit 221 is a ring image (pattern image) obtained by detecting the return light of the ring-shaped luminous flux (ring-shaped measurement pattern) projected on the fundus Ef by the reflex measurement projection system 6 by the image sensor 59. ) Is analyzed. For example, the eye refractive power calculation unit 221 obtains the position of the center of gravity of the ring image from the brightness distribution in the image in which the obtained ring image is drawn, and obtains the brightness distribution along a plurality of scanning directions extending radially from this center of gravity position. , The ring image is specified from this brightness distribution. Subsequently, the optical power calculation unit 221 obtains an approximate ellipse of the specified ring image, and substitutes the major axis and the minor axis of the approximate ellipse into a known equation to obtain a spherical power, an astigmatic power, and an astigmatic axis angle (refraction). Power value) is calculated. Alternatively, the eye refractive power calculation unit 221 can obtain the parameter of the eye refractive power based on the deformation and deviation of the ring image with respect to the reference pattern.

In addition, the optical power calculation unit 221 calculates the radius of curvature of the cornea (corneal curvature) based on the keratling image acquired by the anterior segment observation system 5. For example, the optical power calculation unit 221 calculates the radius of curvature of the strong main meridian and the radius of curvature of the weak main meridian on the anterior surface of the cornea by analyzing the keratling image, and applies statistical processing to these radii of curvature to apply statistical processing to the cornea. Calculate the radius of curvature. This statistical processing may be, for example, averaging, selecting the maximum value, or selecting the minimum value. The eye refractive power calculation unit 221 can calculate the corneal refractive power, the corneal astigmatism degree, and the corneal astigmatism axis angle based on the calculated radius of curvature of the cornea.

The method for determining the radius of curvature of the cornea is not limited to the method using keratling. For example, in addition to the method using the corneal topography system (platidling) described above, an arbitrary corneal shape analysis method such as a method using a slit scan, a method using a Scheimpflug camera, and a method using anterior segment OCT is applied. It is possible. The optical power calculation unit 221 has a function as a part of the corneal shape measurement unit 1010 in the first and second aspects.

The image forming unit 222 forms the image data of the tomographic image of the eye E based on the output (sampling data, interference signal data) from the DAQ 130 of the OCT system 8. This image forming process includes filtering, a fast Fourier transform (FFT), and the like, similar to the conventional (swept source) OCT. By such processing, the reflection intensity profile in the A line (scan path of the measurement light LS in the eye E) is acquired, and the image data (A scan data) of the A line is formed by imaging this reflection intensity profile. Will be done.

Further, the image forming unit 222 forms a plurality of A scan data according to the mode of OCT scan (deflection of the measurement light LS, movement of the A scan position), and arranges these A scan data to obtain two-dimensional image data. Three-dimensional image data can be constructed.

When a plurality of tomographic image data (stack data) are obtained by raster scan or the like, the image forming unit 222 constructs voxel data (volume data) by applying voxelization processing such as interpolation processing to these tomographic image data. can do. Further, the image forming unit 222 can render the stack data or the volume data. The rendering method is arbitrary and may include, for example, volume rendering, multi-section reconstruction (MPR), surface rendering, and the like. Further, the image forming unit 222 can construct a plane image (for example, a front image) from the stack data or the volume data. For example, the image forming unit 222 can construct a projection image by integrating stack data or volume data along each A line.

The data processing unit 223 can execute various data processing. The data processing unit 223 can process the data (OCT data) acquired by using the OCT scan. The OCT data is, for example, interference signal data, reflection intensity profile or image data. The data processing unit 223 can process the image obtained by the anterior segment observation system 5 and the signal (data) output from the line sensor 13 of the Z alignment system 1. The data processing unit 223 can also process data other than the data illustrated here.

For example, the data processing unit 223 can apply segmentation to stack data or volume data. Segmentation is a known process for identifying a partial region in image data. The data processing unit 223 performs segmentation based on the brightness value of the OCT image (two-dimensional tomographic image, three-dimensional image, etc.). For example, each of the plurality of layered tissues in the fundus Ef has a characteristic reflectance, and the image region of these layered tissues also has a characteristic brightness value. The data processing unit 223 executes segmentation so as to specify a target image region based on these characteristic luminance values. The target imaging region is, for example, the inner limiting membrane, nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer, outer nuclear layer, outer limiting membrane, photoreceptor layer, retinal pigment epithelial layer, It corresponds to any tissue of the fundus Ef, such as choroid and strong membrane.

As shown in FIG. 9, the data processing unit 223 includes a first captured image analysis unit 2231, a feature point setting unit 2232, a second evaluation unit 2233, an OCT data analysis unit 2234, and an eyeball model creation unit 2235. It includes the first evaluation unit 2236. As described above, the eye refractive power calculation unit 221 functions as a part (second captured image analysis unit) of the corneal shape measurement unit 1010. In this embodiment, the anterior segment observation system 5 acquires a first captured image and a second captured image of the eye E. The first captured image and the second captured image may be different images from each other or may be the same image.

The first captured image is provided to the first captured image analysis unit 2231 to detect a specific part of the eye E (for example, the apex of the cornea or the center of the pupil). When detecting the apex of the cornea, the anterior segment observation system 5 photographs the eye E in a state where the luminous flux from the XY alignment system 2 is projected, and the bright spot image (Pulkiner image) formed by the luminous flux is photographed. Acquires the first captured image in which is drawn. Alternatively, in the case of detecting the corneal apex, the anterior segment observation system 5 is formed by the pattern light by photographing the eye E in a state where the pattern light from the kerato measurement system 3 or the corneal topography system is projected. The first photographed image in which the resulting Pearn image (keratling image, platidling image) is drawn is acquired. When detecting the center of the pupil, the anterior segment observation system 5 acquires the first captured image in which the pupil of the eye E is depicted. When detecting another specific part, the first captured image corresponding to the specific part is acquired. The first captured image analysis unit 2231 is configured to execute the same data processing as the specific site detection unit 1060 of the second aspect.

Here, when detecting the corneal apex, the element group including the XY alignment system 2, the anterior segment imaging system 5, and the first captured image analysis unit 2231 function as the specific site detection unit 1060 of the second aspect. To do. When detecting the center of the pupil, the element group including the anterior segment imaging system 5 and the first captured image analysis unit 2231 functions as the specific site detecting unit 1060 of the second aspect. When detecting another specific site, the element group including at least the anterior segment imaging system 5 and the first captured image analysis unit 2231 functions as the specific site detecting unit 1060 of the second aspect.

The second captured image is provided to the eye refractive power calculation unit 221 (second captured image analysis unit) for measuring the corneal shape of the eye E. As described above, the optical power calculation unit 221 generates corneal shape data (typically, corneal curvature distribution data or corneal radius of curvature distribution data) which is measurement data by kerato measurement or corneal topography. The eye refractive power calculation unit 221 (second captured image analysis unit) is configured to execute the same data processing as the corneal shape measurement unit 1010 of the first and second aspects. The anterior segment observation system 5 and the optical power calculation unit 221 (second photographed image analysis unit) of the present embodiment function as the corneal shape measurement unit 1010 of the first and second aspects.

The corneal shape data obtained by the eye refractive power calculation unit 221 is provided to the feature point setting unit 2232. The feature point setting unit 2232 functions as the feature point setting unit 1070 of the second aspect, and is configured to execute data processing similar to this.

The second evaluation unit 2233 evaluates the wearing state of the ortho-K lens with respect to the eye E based on the specific portion detected by the first captured image analysis unit 2231 and the feature points set by the feature point setting unit 2232. Second evaluation) is executed. The second evaluation unit 2233 has a part of the functions of the evaluation unit 1040 of the second aspect, and is configured to execute the same data processing.

The OCT unit 300 is an example of the OCT unit 1021 of the first aspect, and typically includes an OCT system 8 and an image forming unit 220, and applies OCT to the fundus Ef of the eye E to generate OCT data. .. The generated OCT data is typically image data and is provided to the OCT data analysis unit 2234.

The OCT data analysis unit 2234 analyzes the OCT data and generates fundus shape data. The OCT data analysis unit 2234 is an example of the fundus shape data generation unit 1022 of the first aspect, and analyzes the OCT data acquired by the OCT unit 300 to generate the fundus shape data. The generated fundus shape data is provided to the eyeball model creation unit 2235.

As described above, the eye refractive power calculation unit 221 (second captured image analysis unit) generates corneal shape data. The eye refractive power calculation unit 221 provides this corneal shape data to the eyeball model creation unit 2235. The corneal shape data provided to the eyeball model creating unit 2235 and the corneal shape data provided to the feature point setting unit 2232 may be the same or different from each other.

The eyeball model creation unit 2235 creates an eyeball model based on at least the corneal shape data provided by the optical power calculation unit 221 and the fundus shape data provided by the OCT data analysis unit 2234. The eyeball model creation unit 2235 is an example of the eyeball model creation unit 1030 of the first and second aspects.

The first evaluation unit 2236 evaluates the effect of the ortho-K lens on the eye E (first evaluation) based on at least the eyeball model created by the eyeball model creation unit 2235. The first evaluation unit 2236 is an example of the evaluation unit 1040 of the first and second aspects.

The operation of the ophthalmic apparatus 2000 according to this aspect will be described. Examples of the operation of the ophthalmic apparatus 2000 are shown in FIGS. 10A to 10C. A storage device (not shown) of the ophthalmic apparatus 2000 stores software for realizing the operation examples shown in FIGS. 10A to 10C. The ophthalmic apparatus 2000 executes a series of processes shown in FIGS. 10A to 10C by operating according to this software.

(S31: Remove the Ortho K lens from the eye)
First, the ortho-K lens to be evaluated is removed from the eye E.

(S32: Performs preparatory operations such as alignment)
Next, a predetermined preparatory operation is performed in the same manner as in step S2 of the first aspect.

(S33: Start projecting pattern light onto the cornea)
Next, the ophthalmic apparatus 2000 projects the pattern light onto the cornea of the eye E by the kerato measurement system 3 or the corneal topography system. The projection of the pattern light is continued at least until the anterior segment image is acquired.

(S34: Capture the anterior segment image)
Next, the ophthalmic apparatus 2000 acquires an anterior segment image of the eye E in a state where the pattern light is projected on the cornea. Typically, the ophthalmologic apparatus 2000 starts moving the anterior segment of the eye by the anterior segment observation system 5 in step S32 and captures the frame obtained after step S33.

The acquired anterior segment image may be not only a pattern image formed by the pattern light but also an image of a luminous flux (bright spot image, Purkinje image) from the XY alignment system 2. Alternatively, the ophthalmic apparatus 2000 may separately acquire the anterior segment image in which the pattern image is depicted and the anterior segment image in which the bright spot image is depicted.

(S35: Detects corneal apex)
The first captured image analysis unit 2231 analyzes the anterior segment image acquired in step S34 to detect the corneal apex. As a result, the position data of the corneal apex of the eye E after the ortho-K lens is removed can be obtained. That is, the position data of the corneal apex of the eye E in which the cornea is deformed by the ortho-K lens can be obtained.

When the image of the luminous flux (bright spot image, Purkinje image) from the XY alignment system 2 is drawn on the anterior segment image, the first captured image analysis unit 2231 sets the X and Y coordinates of the bright spot image on the cornea. It can be obtained as two-dimensional position data of vertices. Further, when the image of the luminous flux from the XY alignment system 2 is drawn on the anterior segment image and the stereo imaging described above is possible, the first imaging image analysis unit 2231 captures images from different directions. The three-dimensional position data of the corneal apex can be obtained from the two bright spot images drawn on the two anterior segment images. On the other hand, when the image of the luminous flux from the XY alignment system 2 is not drawn on the anterior segment image, the first captured image analysis unit 2231 may use, for example, a keratling image (concentric pattern image) projected by the kerato measurement system 3. ), The center of the ring image having the smallest diameter can be obtained as the two-dimensional position data of the corneal apex.

(S36: Generates eye corneal shape data)
The optical power calculation unit 221 (second photographed image analysis unit) analyzes the anterior ocular segment image acquired in step S34 to generate corneal shape data (for example, corneal curvature distribution data or corneal curvature radius distribution data). .. Further, the eye refractive power calculation unit 221 (second photographed image analysis unit) may generate height distribution data obtained by integrating the corneal curvature distribution data twice as corneal shape data. The height distribution data is, for example, data expressing the relative height with respect to a predetermined position (for example, the position of the apex of the cornea).

(S37: Determine the fitting center from the corneal shape data)
The feature point setting unit 2232 sets the feature point from the corneal shape data acquired in step S36. In this operation example, the fitting center is required as a feature point.

As described above, the fitting center is the center of the mathematical formula that approximates the corneal shape data (typically, the center of the fitting curved surface, the center of the fitting curve). This formula may be a centrally symmetric formula and may be an aspherical formula. This aspherical expression may be, for example, an expression including at least the expression of the conic surface, and may be an expression obtained by adding an even-order polynomial to the expression of the conic surface.

An equation obtained by adding an even-order polynomial to the equation of the conic plane is typically expressed as: z = (ch ² / (1 + √ (1- (1 + k) c ² h ² ) )) + Ah ⁴ + Bh ⁶ + Ch ^8. Where z is the sag amount of the plane parallel to the Z axis, h is the coordinates in any direction on the XY plane, c is the curvature, k is the conic coefficient, A, B and C is the coefficient of the fourth-order, sixth-order, and eighth-order terms of the polynomial, respectively. Here, if h is (hh ₀ ), an aspherical expression regarding an arbitrary center position h ₀ can be expressed.

The feature point setting unit 2232 applies the aspherical fitting by such a mathematical formula to the corneal shape data. The aspherical fitting may be, for example, an aspherical fitting centered on the apex of the cornea or an aspherical fitting having an arbitrary center.

Since the eye E is assumed to be an astigmatic eye in this embodiment, the feature point setting unit 2232 applies, for example, a two-dimensional center-symmetrical aspherical fitting to a certain meridian of the cornea, and the center (fitting center) thereof. ) To find the coordinates. Alternatively, when the corneal shape data is three-dimensional data, the feature point setting unit 2232 can apply the point-symmetrical aspherical fitting to the corneal shape data and obtain the coordinates of the center (fitting center). ..

(S38: Calculate the deviation of the corneal apex and the fitting center)
The second evaluation unit 2233 compares the position data of the corneal apex detected in step S35 with the position data of the fitting center determined in step S37, and calculates the deviation Δ between them.

The offset delta, for example, deviation [Delta] X in the X direction, the Y-direction deflection [Delta] Y, deviation [Delta] xy = √ in the XY plane (ΔX ² + ΔY ^2), and, excursion ΔXYZ in XYZ space = √ (ΔX ² + ΔY It may be any of ² + ΔZ ² ). The deviation Δ may be a deviation ΔYZ in the YZ plane, a deviation ΔZX in the ZX plane, or a deviation according to another definition.

(S39: Determine whether the deviation exceeds the threshold value)
The second evaluation unit 2233 compares the deviation Δ calculated in step S38 with the predetermined threshold value. Here, the threshold value is set to, for example, 0.5 mm, but may be set to another value. The ophthalmic apparatus 2000 may display the comparison result on the display unit 270. The result of comparison between the deviation Δ and the threshold value is used in step S48 described later.

(S40: OCT is applied to the fundus to generate OCT data)
Next, the OCT unit 300 applies an OCT scan to the fundus Ef of the eye E to generate OCT data.

(S41: Generate fundus shape data)
The OCT data analysis unit 2234 analyzes the OCT data generated in step S40 to generate fundus shape data.

(S42: Create an eyeball model)
The eyeball model creation unit 2235 creates an eyeball model based on at least the corneal shape data generated in step S36 and the fundus shape data generated in step S41.

(S43: Start simulation with reference to corneal apex)
Subsequently, the first evaluation unit 2236 starts a simulation using the eyeball model created in step S42. The simulation of this example includes a series of processes shown in the following steps S44 to S46.

This simulation is performed, for example, with reference to the corneal vertices detected in step S35. That is, this simulation assumes that the corneal apex position detected in step S35 corresponds to the foveal position of the fundus Ef, and uses this foveal position as the simulation center (in other words, this hypothetical foveal position). It is executed (with the simulation center as the straight line (eye axis) connecting the corneal apex position and the corneal apex position).

As described above, the reference position of the simulation (simulation center) affects the result of the first evaluation. In this example, the corneal apex (and the corresponding retinal center) detected in step S35 is the simulation center, but the original corneal apex position may be the simulation center. The original corneal apex position can be obtained from, for example, the positional relationship with respect to the pupil (pupil center), iris (iris center), or corneal edge (white-to-white, WTW) detected by another method. ..

(S44: Calculate the peripheral refractive power)
The first evaluation unit 2236 calculates the refractive power (peripheral refractive power) of the peripheral region of the eye E (eyeball model) in the same manner as the focal position specifying unit 1041 of the first aspect.

Peripheral refractive power is calculated for at least one position. For example, the refractive frequency distribution in the peripheral region of the eye E (eyeball model) can be obtained.

(S45: Find the focal position of the peripheral area)
Next, the first evaluation unit 2236 is an eye model based on the peripheral refractive power calculated in step 44 and the eye model created in step S42, similarly to the focus position specifying unit 1041 of the first aspect. The focal position of the virtual light beam incident on the periphery of the fundus of the eye is specified.

The focal position is determined for at least one virtual ray tilted with respect to the simulation center (virtual eye axis). For example, the focal position distribution can be obtained by obtaining the focal position for each of the plurality of virtual rays.

(S46: Determine the positional relationship between the focal position and the retinal surface)
Next, the first evaluation unit 2236 determines the positional relationship between the focal position obtained in step S45 and the retinal surface of the eyeball model created in step S42, similarly to the first evaluation execution unit 1042 of the first aspect. judge.

More specifically, the first evaluation unit 2236 determines whether or not the focal position obtained in step S45 is located deeper than the retinal surface in the peripheral portion of the fundus of the eyeball model created in step S42. ..

(S47: Is the focal position behind the retinal surface?)
When it is determined that the focal position obtained in step S45 is located deeper than the retinal surface in the peripheral part of the fundus of the eyeball model created in step S42 (S47: Yes), the process proceeds to step S49. To do. In this case, in step S49, the determination result of step S39 is taken into consideration as in step S48.

On the other hand, when it is determined that the focal position obtained in step S45 is located in front of the retinal surface in the peripheral portion of the fundus of the eyeball model created in step S42 (S47: No), the process is step S48. Move to.

(S48: Deviation in S39> Threshold?)
When it is determined that the focal position is located in front of the surface of the retina (S47: No), the comparison result between the deviation Δ obtained in step S39 and the threshold value is referred to. When it is determined that the deviation Δ exceeds the threshold value (S48: Yes), the process proceeds to step S49. On the other hand, when it is determined that the deviation Δ is equal to or less than the threshold value (S48: No), the process proceeds to step S50.

(S49: Propose a review of the Ortho K lens prescription)
As described above, when it is determined that the focal position is located behind the surface of the retina (S47: Yes), in this step, the first evaluation unit 2236 is obtained in step S39 as in step S48. Refer to the comparison result between the deviation Δ and the threshold value. When it is determined that the deviation Δ exceeds the threshold value, that is, when the results of both evaluations are “NG”, the periphery has a shape and size that better fits the eye E and is different from the current one. It is proposed to change to an ortho-K lens with a degree of refraction (end). On the other hand, if it is determined that the deviation Δ does not exceed the threshold value, it is proposed to change to an ortho-K lens having a peripheral refractive index different from the current one (end).

When it is determined that the focal position is located in front of the surface of the retina (S47: No) and the deviation Δ exceeds the threshold value (S48: Yes), a shape that better fits the eye E or It is proposed to change to an ortho-K lens with a size (end).

(S50: Propose to continue using the current Ortho K lens)
When it is determined that the focal position is located in front of the retinal surface (S47: No) and the deviation Δ does not exceed the threshold value (S48: No), the current Ortho-K lens is used. Is proposed to continue (end).

If this time is the second and subsequent evaluations, and if it is determined to be "Yes" in either step S47 or step S48, it is determined that orthokeratology is not applicable, and another treatment method is used. I can make a suggestion.

The control unit 210 is the result of the second evaluation in step S39 (determination result in step S48), the result of the first evaluation in step S46 (determination result in step S47), the content proposed in step S49, and the content proposed in step S50. You can output, save, and record the contents. Further, the order of the steps shown in FIGS. 10A to 10C can be arbitrarily changed.

The evaluation (second evaluation) of the mounted state of the ortho-K lens in this embodiment will be described with reference to FIGS. 11A and 11B. Here, FIG. 11A corresponds to a case where the mounting state is good, and FIG. 11B corresponds to a case where the mounting state is poor.

Reference numeral 2100 in FIG. 11A indicates a map (corneal topomap) created based on the corneal curvature distribution data obtained by corneal topography. The distribution represented by the corneal topomap 2100 is, for example, a corneal curvature distribution, a corneal radius of curvature distribution, a corneal curvature distribution or a refractive power distribution based on the corneal radius of curvature distribution, a height distribution based on the corneal curvature distribution, or another distribution. You can. Hereinafter, the corneal topomap 2100 will be described as a map expressing the corneal curvature distribution, but the same matter holds true even when other distributions are applied.

Reference numeral 2110 indicates a predetermined meridian of the cornea. Reference numeral 2120 is a graph showing the curvature distribution on the meridian 2110. Reference numeral 2130 indicates a correction center (fitting center) determined by applying an aspherical fitting to the curvature distribution graph 2120. Reference numeral 2200 indicates the position of the corneal apex detected by analyzing the anterior segment image.

Here, the corneal apex position 2200 is an example of the corneal shape data generated in step S36 of FIG. 10A, and the fitting center 2120 is an example of the position determined in step S37. In this case, step S38 calculates the deviation Δ1 (deviation in the direction along the meridian 2110) between the corneal apex position 2200 and the fitting center 2130.

In step S39, it is determined whether or not the deviation Δ1 exceeds the threshold value. In this example, the deviation Δ1 is determined to be equal to or less than the threshold value, and an evaluation result is obtained that the currently used ortho-K lens is in an appropriate state of attachment. However, this does not prevent the user from reviewing the prescription regarding the wearing state of the Ortho K lens by referring to the deviation Δ1, the corneal topomap 2100, the curvature distribution graph 2120, other examination data, the interview data, and the like.

On the other hand, reference numeral 2300 in FIG. 11B indicates another corneal topomap. Reference numeral 2310 indicates a predetermined meridian of the cornea. Reference numeral 2320 is a graph showing the curvature distribution on the meridian 2310. Reference numeral 2330 indicates a correction center (fitting center) determined by applying an aspherical fitting to the curvature distribution graph 2320. Reference numeral 2400 indicates the position of the corneal apex detected by analyzing the anterior segment image.

Similar to the example shown in FIG. 11A, the corneal apex position 2400 is an example of the corneal shape data acquired in step S36 of FIG. 10A, and the fitting center 2320 is an example of the position determined in step S37. In this case, step S38 calculates the deviation Δ2 (deviation in the direction along the meridian 2310) between the corneal apex position 2400 and the fitting center 2330.

In step S39, it is determined whether or not the deviation Δ2 exceeds the threshold value. In this example, it is determined that the deviation Δ2 exceeds the threshold value, and an evaluation result is obtained that the currently used ortho-K lens is not in an appropriate state of attachment.

Here, comparing the two curvature distribution graphs 2120 and 2320, in the curvature distribution graph 2120, the inclination of the left end portion and the inclination of the right end portion are substantially equal, and the graph shape is relatively symmetrical, while the curvature distribution graph. In 2320, the inclination of the left end portion is gentler than the inclination of the right end portion, and the graph shape is relatively asymmetrical. This is because in the example shown in FIG. 11A, the deviation between the center position of the ortho-K lens and the apex position of the cornea is relatively small, and the effect of the ortho-K lens is exhibited almost as expected, whereas the example shown in FIG. 11B. The deviation is relatively large, suggesting that the effect of the Ortho K lens is not sufficiently obtained.

As described above, according to the example shown in FIG. 11A, the degree of coincidence between the corneal apex and the correction center is high, the fitting of the ortho-K lens is good, and the aspherical shape (the shape of the ortho-K lens or its approximate shape). Is symmetrical about the apex of the cornea, and it can be seen that the ortho-K lens matches the cornea well. Furthermore, it can be seen that various lens parameters such as the base curve of the central region of the Ortho-K lens are appropriate, and the corneal curvature distribution as intended (close to the target) is achieved.

On the other hand, according to the example shown in FIG. 11B, the degree of coincidence between the corneal apex and the correction center is low, the fitting of the ortho-K lens is poor, the aspherical shape is asymmetric with respect to the corneal apex, and the ortho-K lens. It turns out that does not match the cornea. Furthermore, it can be seen that various lens parameters such as the base curve of the central region of the Ortho K lens are not appropriate, and the intended corneal curvature distribution is not achieved. These suggest that the Ortho-K lens may have shifted at night. If this deviation is large, it may adversely affect eyesight.

The second evaluation unit 2233 may be configured to quantify and / or qualitate these evaluation indexes. For example, the second evaluation unit 2233 quantitatively and / or qualitatively expresses the degree of coincidence between the corneal apex and the correction center based on the magnitude of the deviation Δ, and quantitatively and / or qualitatively expresses the symmetry number of the curvature distribution graph. / Or can be expressed qualitatively. Here, the symmetry quantification is, for example, a calculation for obtaining the difference or ratio between the area of the left side portion and the area of the right side portion of the curvature distribution graph, or a calculation for obtaining the laterality of the difference between the curvature distribution graph and the symmetry curve. Etc. may be included.

Similarly, the first evaluation unit 2236 may be configured to quantify and / or qualitate the positional relationship between the focal position and the retinal surface obtained in step S46. For example, the first evaluation unit 2236 can calculate not only which side (back side or front side) the focal position is arranged with respect to the retinal surface, but also the amount of deviation of the focal position with respect to the retinal surface. ..

In step S49 (review of the prescription of the ortho-K lens), for example, review of various parameters of the ortho-K lens, search for the optimum value, simulation, and the like are performed. The parameters of the Ortho-K lens are the diameter of the entire lens, the diameter of the base curve in the center of the lens, the dimensions of the chord of the optical zone (treatment zone), the width and depth of the transition zone (return zone), and the peripheral zone. (Landing zone) diameter, angle, width, end width, refractive power, etc.

<Fourth aspect>
The ophthalmic apparatus according to the fourth aspect will be described. Hereinafter, unless otherwise specified, the terms, symbols, etc. in the third aspect shall apply mutatis mutandis.

Similar to the third aspect, this aspect applies when an ortho-K lens is prescribed relative to the apex of the cornea of the eye. Further, as in the third aspect, in this aspect, when the ortho-K lens is properly attached with reference to the corneal apex of the eye, the corneal apex after removing the ortho-K lens is the deformation center (fitting center). Etc.), and it is assumed that they should match.

On the other hand, unlike the third aspect, in this aspect, it is assumed that the eye has astigmatism and that the shape (aspherical surface) of the cornea deformed by the ortho-K lens is isotropic. Here, the presence of astigmatism in the eye means, for example, that the measured value of the degree of astigmatism of the eye exceeds a predetermined threshold value, and this embodiment can be applied to such an eye.

This aspect can be realized by an ophthalmic apparatus having the same configuration and function as the third aspect. However, while the third aspect targets the astigmatic eye, this aspect targets the astigmatic eye. Therefore, instead of step S37 in FIG. 10A in the third aspect, for example, the approximate expression shown below is used. (Biconic surface equation) is applied to the fitting of corneal shape data.

The approximation applied in this embodiment is typically expressed as: z = ((c _x x ² + _cy y ² ) / (1 + √ (1- (1 + k _x )) ) c _x ² x ^2- (1 + k _y ) c _y ² y ² ))) + A _R ((1-A _P ) x ² + (1 + A _P ) y ² ) ² + B _R ((1) -B _P ) x ² + (1 + B _P ) y ² ) ³ + C _R ((1-C _P ) x ² + (1 + C _P ) y ² ) ⁴ . Here, z is the sag amount of the plane parallel to the Z axis, x is the X coordinate, y is the Y coordinate, c _x is the curvature in the X direction, c _y is the curvature in the Y direction, and k _x is the cornic coefficient in the X direction. k _y is the Y-direction of the conic coefficient, a _R, B _R and C _R are fourth order, respectively conic, sixth and eighth order coefficient of rotational symmetry portion, a _P, fourth order, respectively B _P and C _P conic , 6th and 8th order non-rotational symmetry parts. Here, if x is (xx ₀ ) and y is (yy ₀ ), an aspherical expression regarding an arbitrary center position (x ₀ , y ₀ ) can be expressed. As a special case, if k _x = k _y and c _x = c _y , the same point-symmetrical cornic surface equation as in the third aspect can be obtained.

The feature point setting unit 2232 applies the aspherical fitting by such a mathematical formula to the corneal shape data. The aspherical fitting may be, for example, an aspherical fitting centered on the apex of the cornea or an aspherical fitting having an arbitrary center.

Since the eye E is assumed to be an astigmatic eye in this embodiment, fitting is performed on two (or more) meridians that are different from each other. Fitting is typically performed on two meridians that are orthogonal to each other. The two meridians are typically a meridian along the astigmatic axis of the eye E and a meridian orthogonal to it. That is, the feature point setting unit 2232 first applies a two-dimensional center-symmetrical aspherical fitting to the first meridian of the cornea, and obtains the coordinates of the center (fitting center). Next, the feature point setting unit 2232 performs the same fitting on the second meridian different from the first meridian, and obtains the coordinates of the center (fitting center). Alternatively, when the corneal shape data is three-dimensional data, the feature point setting unit 2232 may apply the fitting by the mathematical formula of the biconic surface to the corneal shape data and obtain the coordinates of the center (fitting center). it can.

With respect to matters other than those described above, the third aspect can be applied to this aspect.

<Fifth aspect>
The ophthalmic apparatus according to the fifth aspect will be described. Hereinafter, unless otherwise specified, the terms, symbols, etc. in the third aspect shall apply mutatis mutandis.

Unlike the third and fourth aspects, this aspect applies when an ortho-K lens is prescribed relative to the pupil of the eye. In this aspect, it is assumed that the center of the pupil after removing the ortho-K lens should coincide with the center of correction. Further, as in the third aspect, it is assumed that the eye E is an astigmatic eye and that the shape (aspherical surface) of the cornea deformed by the ortho-K lens is isotropic. This aspect can be realized by an ophthalmic apparatus having the same configuration and function as the third aspect.

In this embodiment, the pupil center is detected instead of step S35 in FIG. 10A, the deviation between the pupil center and the fitting center is calculated instead of step S38, and the pupil center is performed instead of the simulation started in step S43. A simulation based on is executed.

The detection of the center of the pupil will be described. In this example, the anterior segment observation system 5 acquires a photographed image in which the pupil of the eye E is depicted. For example, the first captured image analysis unit 2231 analyzes the captured image obtained by photographing the eye E from the front by the anterior segment observation system 5, detects the pupil edge, and applies an elliptical fitting to the pupil edge. To find an ellipse that approximates the pupil edge, and find the center of this ellipse. This elliptical center is adopted as the two-dimensional position data of the pupil center. In another example, the first captured image analysis unit 2231 analyzes the captured image obtained by photographing the eye E from the front by the anterior segment observation system 5, detects the pupil edge or the pupil region, and determines the center of gravity thereof. You may ask. This ellipse center of gravity is adopted as two-dimensional position data of the ellipse center. In still another example, when the stereo shooting described above is possible, the first shot image analysis unit 2231 performs the same processing on two shot images (two front eye images) shot from different directions. By applying, the three-dimensional position data of the center of the pupil can be obtained. In this aspect, the element group including the anterior segment imaging system 5 and the first captured image analysis unit 2231 function as the specific site detection unit 1060 of the second aspect.

The evaluation (second evaluation) of the mounted state of the ortho-K lens in this embodiment will be described with reference to FIGS. 12A and 12B. Here, FIG. 12A corresponds to a case where the mounting state is good, and FIG. 12B corresponds to a case where the mounting state is poor.

The corneal topomap 2500 shown in FIG. 12A will be described as a map expressing the corneal curvature distribution, but the same matter holds true when other distributions are applied. Reference numeral 2510 indicates a predetermined meridian of the cornea. Reference numeral 2520 is a graph showing the curvature distribution on the meridian 2510. Reference numeral 2530 indicates a correction center (fitting center) determined by applying an aspherical fitting to the curvature distribution graph 2520. Reference numeral 2600 indicates the position of the center of the pupil detected by analyzing the anterior segment image.

In this case, the deviation Δ3 (deviation in the direction along the meridian 2510) between the pupil center position 2600 and the fitting center 2530 is calculated, and it is determined whether or not the deviation Δ3 exceeds the threshold value. In this example, the deviation Δ3 is determined to be below the threshold value, and an evaluation result is obtained that the currently used ortho-K lens is in an appropriate state of attachment.

On the other hand, reference numeral 2700 in FIG. 12B indicates another corneal topomap. Reference numeral 2710 indicates a predetermined meridian of the cornea. Reference numeral 2720 is a graph showing the curvature distribution on the meridian line 2710. Reference numeral 2730 indicates a correction center (fitting center) determined by applying an aspherical fitting to the curvature distribution graph 2720. Reference numeral 2800 indicates the position of the center of the pupil detected by analyzing the anterior segment image.

In this case, the deviation Δ4 (deviation in the direction along the meridian 2710) between the pupil center position 2800 and the fitting center 2730 is calculated, and it is determined whether or not the deviation Δ4 exceeds the threshold value. In this example, it is determined that the deviation Δ4 exceeds the threshold value, and an evaluation result is obtained that the currently used ortho-K lens is not in an appropriate state of attachment.

The slope of the curvature distribution graph, the symmetry of the curvature distribution graph, the quantification and qualitativeization of the evaluation index, the review of the formulation of the ortho-K lens, and the like may be the same as those of the third aspect.

<Sixth aspect>
The ophthalmic apparatus according to the sixth aspect will be described. Hereinafter, unless otherwise specified, the terms, symbols, etc. in the above embodiments are applied mutatis mutandis.

Similar to the fifth aspect, this aspect is applied when an ortho-K lens is prescribed with reference to the pupil of the eye. Further, as in the fifth aspect, in this aspect, when the ortho-K lens is properly attached with reference to the center of the pupil of the eye, the center of the pupil after removing the ortho-K lens is the correction center (corneal center). , Fitting center, etc.).

On the other hand, unlike the fifth aspect, in this aspect, it is assumed that the eye has astigmatism and that the shape (aspherical surface) of the cornea deformed by the ortho-K lens is isotropic. Here, the presence of astigmatism in the eye means, for example, that the measured value of the degree of astigmatism of the eye exceeds a predetermined threshold value, and this embodiment can be applied to such an eye.

This aspect can be realized by an ophthalmic apparatus having the same configuration and function as the fifth aspect. However, while the fifth aspect targets the astigmatic eye, this aspect targets the astigmatic eye, so the approximation formula of the biconic surface described in the fourth aspect is applied to the fitting of the corneal shape data. Will be done.

Since the eye E is assumed to be an astigmatic eye in this embodiment, fitting is performed on two (or more) meridians that are different from each other. Fitting is typically performed on two meridians that are orthogonal to each other. The two meridians are typically a meridian along the astigmatic axis of the eye E and a meridian orthogonal to it. That is, the feature point setting unit 2232 first applies a two-dimensional center-symmetrical aspherical fitting to the first meridian of the cornea, and obtains the coordinates of the center (fitting center). Next, the feature point setting unit 2232 performs the same fitting on the second meridian different from the first meridian, and obtains the coordinates of the center (fitting center). Alternatively, when the corneal shape data is three-dimensional data, the feature point setting unit 2232 may apply the fitting by the mathematical formula of the biconic surface to the corneal shape data and obtain the coordinates of the center (fitting center). it can.

With respect to matters other than those described above, the fifth aspect can be applied to this aspect.

<Effect>
Some effects of the ophthalmic apparatus according to the exemplary embodiments described above will be described.

The ophthalmic apparatus according to the exemplary embodiment includes a corneal shape measuring unit, a fundus shape measuring unit, an eyeball model creating unit, and an evaluation unit. For example, the ophthalmic apparatus 1000 (1500) includes a corneal shape measuring unit 1010, a fundus shape measuring unit 1020, an eyeball model creating unit 1030, and an evaluation unit 1040. In addition, the ophthalmic apparatus 2000 includes a corneal shape measuring unit including an anterior ocular region observation system 5 and an optical power calculation unit 221 (second captured image analysis unit), and a fundus shape measurement including an OCT unit 300 and an OCT data analysis unit 2234. A unit, an eyeball model creation unit 2235, and an evaluation unit including a first evaluation unit 2236 are included.

The corneal shape measuring unit is configured to measure the corneal shape of the eye after the ortho-K lens is removed. The fundus shape measuring unit measures the fundus shape of the eye. The eyeball model creating unit creates an eyeball model based on at least the corneal shape data acquired by the corneal shape measuring unit and the fundus shape data acquired by the fundus fundus shape measuring unit. The evaluation unit executes the first evaluation regarding the effect of the ortho-K lens on the eye based on at least the eyeball model created by the eyeball model creation unit.

According to such an exemplary embodiment, the suitability of the Ortho K lens can be automatically determined. Therefore, it is possible to actually obtain the expected refraction correction effect and the material for judging what the refraction state of the peripheral vision is (that is, whether or not the Ortho-K lens is mounted at an appropriate position at night). It is possible to provide the user (doctor, etc.) with the material for determining whether or not the lens is present.

In the ophthalmic apparatus according to the exemplary embodiment, the evaluation unit may include a focus position specifying unit and a first evaluation execution unit. The evaluation unit 1040A of the ophthalmic apparatus 1000 includes a focus position specifying unit 1041 and a first evaluation executing unit 1042 (see FIG. 2C). The focal position specifying portion identifies the focal position of the virtual light beam incident on the peripheral portion of the fundus of the eyeball model. The first evaluation execution unit executes the first evaluation based on the positional relationship between the specified focal position and the peripheral portion of the fundus of the eyeball model.

According to such a configuration, by obtaining the focal position of the peripheral visual field under the influence of the ortho-K lens, is it possible to obtain the desired refraction correction effect (particularly, the effect of suppressing the progression of myopia) by the current ortho-K lens? It is possible to provide a material for determining whether or not.

In the ophthalmic apparatus according to the exemplary embodiment, the eyeball model creating unit determines the relative position between the corneal shape data and the fundus shape data based on at least the predetermined anterior segment reference position and the fundus reference position to create the eyeball model. It may be configured as follows.

According to such a configuration, an eyeball model can be created after positioning the corneal shape data and the fundus shape data using a predetermined anterior segment reference position and a predetermined fundus reference position, and such an eyeball model. Since the simulation can be performed with the simulation center based on the anterior segment reference position and the fundus reference position as a reference while using the above, it is possible to improve the accuracy and reproducibility of the first evaluation.

In the ophthalmic apparatus according to the exemplary embodiment, an eyeball model can be created with reference to the cornea. For example, the eyeball model creation unit creates an eyeball model by determining the relative position between the corneal shape data and the fundus shape data at least based on the corneal apex position as the anterior ocular segment reference position and the foveal position as the fundus reference position. It may be configured to do so. Here, the corneal apex position may be either a position before the ortho-K lens is attached (original corneal apex position) or a position after the ortho-K lens is removed. Further, the eyeball model creating unit may be configured to create an eyeball model by further determining a relative position between the corneal shape data and the fundus shape data based on a predetermined axial length data (standard value or measured value). ..

According to such a configuration, an eyeball model can be created after positioning the corneal shape data and the fundus shape data using the corneal apex position and the fovea centralis position, and the corneal apex position can be created using such an eyeball model. Since the simulation can be performed with the simulation center based on the position of the fovea centralis as a reference, it is possible to improve the accuracy and reproducibility of the first evaluation.

In the ophthalmic apparatus according to the exemplary embodiment, an eyeball model can be created with reference to the pupil. For example, the eyeball model creation unit creates an eyeball model by determining the relative position between the corneal shape data and the fundus shape data at least based on the pupil center position as the anterior ocular segment reference position and the foveal position as the fundus reference position. It may be configured to do so. Here, the eyeball model creation unit further determines the relative position between the corneal shape data and the fundus shape data based on the predetermined axial length data (standard value / measured value) and the anterior chamber depth data (standard value / measured value). It may be configured to create an eye model.

According to such a configuration, an eyeball model can be created after positioning the corneal shape data and the fundus shape data using the pupil position and the fovea centralis position, and the pupil center position (using such an eyeball model). Alternatively, since the simulation can be performed with reference to the simulation center based on the corneal apex position set based on this) and the foveal position, it is possible to improve the accuracy and reproducibility of the first evaluation.

In the ophthalmic apparatus according to the exemplary embodiment, the eyeball model creating unit may include an anterior segment reference position specifying portion that analyzes corneal shape data to specify an anterior segment reference position. The eye model creation unit 1030A of the ophthalmic apparatus 1000 includes an anterior eye reference position specifying unit 1031 (see FIG. 2A). According to such a configuration, it is not necessary to separately acquire data (photographing, etc.) for setting the anterior segment reference position.

In the ophthalmologic apparatus according to the exemplary embodiment, the fundus shape measuring unit includes an OCT unit that applies optical coherence tomography to the fundus of the eye to generate OCT data, and a fundus that analyzes the OCT data to generate fundus shape data. It may include a shape data generation unit. In addition, the eyeball model creating unit may include a fundus reference position specifying unit that analyzes the OCT data and specifies the fundus reference position. The fundus shape measuring unit 1020A of the ophthalmologic apparatus 1000 includes an OCT unit 1021 and a fundus shape data generating unit 1022, and the eyeball model creating unit 1030B includes a fundus reference position specifying unit 1032 (see FIG. 2B). According to such a configuration, it is not necessary to separately acquire data (photographing, etc.) for setting the fundus reference position.

The ophthalmic apparatus according to the exemplary embodiment may further include a specific site detection unit and a feature point setting unit. The ophthalmic apparatus 1500 includes a specific site detection unit 1060 and a feature point setting unit 1070. In addition, the ophthalmic apparatus 2000 includes a first captured image analysis unit 2231 that functions as a specific site detection unit, and a feature point setting unit 2232. The specific site detection unit detects a specific site of the eye (for example, the apex of the cornea or the center of the pupil) after removing the ortho-K lens. The feature point setting unit sets the feature point from the corneal shape data acquired by the corneal shape measurement unit. Here, the corneal shape data provided to the feature point setting unit may be the same as the corneal shape data provided to the eyeball model creation unit, or may be different from each other. In this example, the evaluation unit executes a second evaluation regarding the wearing state of the ortho-K lens with respect to the eye based on the specific part detected by the specific part detection unit and the feature point set by the feature point setting unit. It may be configured to do so.

According to such a configuration, it is possible to automatically determine the suitability of the mounting position of the Ortho K lens. Therefore, it becomes possible to provide more diagnostic materials to users (doctors, etc.). It is also possible to perform a comprehensive evaluation based on the result of the first evaluation and the result of the second evaluation.

In the ophthalmic apparatus according to the exemplary embodiment, the feature point setting unit may be configured to set feature points based on an approximate expression of corneal shape data by a centrally symmetric expression. This approximate expression is, for example, a centrally symmetric curved surface expression or a curve expression. According to such a configuration, it is possible to perform approximation (fitting) according to the shape of the cornea deformed by the ortho-K lens having a centrally symmetrical shape.

In an exemplary embodiment, the centrally symmetric equation used as the approximate equation may be an aspherical equation. That is, the feature point setting unit may be configured to set feature points based on an approximate expression of corneal shape data by a predetermined aspherical expression. According to such a configuration, it is possible to perform fitting according to the shape of the cornea deformed by the ortho-K lens having the aspherical shape portion.

In an exemplary embodiment, the predetermined aspherical expression may be an expression that includes at least a conic surface expression or a biconic surface expression. With such a configuration, it is possible to perform fitting according to the shape of the cornea deformed by the Ortho-K lens having a conic-shaped or bi-conic-shaped portion.

In an exemplary embodiment, the predetermined aspherical expression may be an expression obtained by adding an even-order polynomial to a conic surface expression or an expression obtained by adding an even-order polynomial to a biconic surface expression. By using such an aspherical type, it becomes possible to perform aspherical fitting to the shape of the cornea deformed by the ortho-K lens having a shape having an inflection point with high accuracy.

In an exemplary embodiment, fitting may be performed in at least one direction (meridian) of the cornea if the given aspherical formula includes at least the formula for the conic plane. That is, the feature point setting unit may be configured to approximate the corneal shape data in at least one direction by an aspherical expression including at least a conic surface equation. According to such a configuration, when the aspherical property of the corneal shape is isotropic as in an astigmatic eye, for example, one (or more) meridian lines are preferably fitted by the equation of the cornic surface. It is also possible, and in the case where the aspherical property of the corneal shape is isotropic, for example, astigmatic eyes, it is possible to preferably perform fitting by the equation of the conic surface for two (or more) meridian lines. It is possible.

In an exemplary embodiment, if a given aspherical formula includes at least a conic plane formula, fitting may be performed in each of two directions (two meridians) orthogonal to each other in the cornea. That is, the feature point setting unit may be configured to approximate the corneal shape data in each of the two directions orthogonal to each other by an aspherical expression including at least the equation of the conic surface. According to such a configuration, when the aspherical surface of the corneal shape is isotropic as in an astigmatic eye, it is possible to suitably fit two meridians orthogonal to each other by the equation of the conic surface. Is.

In an exemplary embodiment, if the given aspherical formula includes at least the conic plane formula, fitting may be performed for the astigmatic axis direction of the cornea and the direction orthogonal thereto. That is, the feature point setting unit may be configured to approximate the corneal shape data in each of the astigmatic axis direction of the eye and the direction orthogonal to the astigmatic axis direction of the eye by an aspherical type including at least the formula of the conic surface. According to such a configuration, it is possible to preferably perform fitting by the formula of the conic surface for astigmatic eyes.

In an exemplary embodiment, three-dimensional fitting may be performed if the given aspherical formula includes at least the formula for the biconic surface. That is, the feature point setting unit may be configured to approximate the corneal shape data by a three-dimensional aspherical expression including at least the equation of the biconic surface. According to such a configuration, it is possible to suitably perform fitting according to the three-dimensional shape of the cornea.

In an exemplary embodiment, the feature point setting unit may be configured to set the center of the approximate expression of the corneal shape data by the centrally symmetric expression as the feature point based on the corneal shape data. According to such a configuration, it is possible to suitably set the feature points of the cornea deformed by the ortho-K lens having a centrally symmetric shape based on the fitting by the centrally symmetric equation.

In an exemplary embodiment, the specific site detection unit may be configured to detect the corneal apex as a specific site, and the evaluation unit is located between the corneal apex and the center of the approximate expression by a centrally symmetric expression. It may be configured to perform an evaluation of the wearing state of the ortho-K lens with respect to the eye based on the deviation of. According to such a configuration, it is possible to preferably evaluate, for example, an ortho-K lens formulated based on the apex of the cornea.

In an exemplary embodiment, the specific site detection unit may be configured to detect the center of the pupil as a specific site, and the evaluation unit is located between the center of the pupil and the center of the approximate expression by a centrally symmetric expression. It may be configured to perform an evaluation of the wearing state of the Ortho K lens with respect to the eye based on the deviation of. According to such a configuration, it is possible to preferably evaluate, for example, an ortho-K lens prescribed based on the pupil.

In an exemplary embodiment, the corneal shape measuring unit may be configured to acquire the curvature distribution data or the radius of curvature distribution data of the cornea as the corneal shape data. According to such a configuration, the corneal shape data obtained by a general corneal shape measuring device such as a keratometer, a corneal topographer, or an OCT device can be used for evaluation of an ortho-K lens.

In an exemplary embodiment, the corneal shape measuring unit may be configured to acquire corneal height distribution data as corneal shape data. According to such a configuration, the height distribution data obtained by integrating the corneal shape data obtained by a general corneal shape measuring device twice can be used for the evaluation of the ortho-K lens.

An exemplary embodiment can provide a method of controlling an ophthalmic apparatus including an imaging unit that photographs the eye, an OCT unit that applies OCT to the fundus, and a processor. For example, the ophthalmic apparatus 1000 (1500) includes an imaging unit (optical system, imaging element, camera, etc.) that photographs the anterior segment of the eye, and an OCT unit (optical system, imaging element, drive mechanism, processor, etc.) that applies OCT to the fundus. ) And (one or more) processors. Further, the ophthalmic apparatus 2000 includes an anterior ocular segment observation system 5 that functions as an imaging system, an OCT unit 300, and a computer including a processor.

In the control method according to the exemplary embodiment, in the first control step, the photographing unit is controlled in order to acquire a captured image of the eye after removing the ortho-K lens. In the second control step, the OCT unit is controlled in order to acquire OCT data of the fundus of the eye. In the third control step, the processor is controlled to analyze the captured image in order to acquire the corneal shape data of the eye. In the fourth control step, the processor is controlled to analyze the OCT data in order to acquire the fundus shape data of the eye. In the fifth control step, the processor is controlled to create an eyeball model based on at least the corneal shape data and the fundus shape data. In the sixth control step, the processor is controlled to perform a first evaluation of the effect of the orthokeratology lens on the eye, at least based on the eye model.

It is possible to combine any of the matters described with respect to the ophthalmic device according to the exemplary embodiment with such a control method of the ophthalmic device.

It is possible to provide a program for causing an ophthalmic apparatus including a computer to execute a control method according to an exemplary embodiment. It is possible to combine this program with any of the items described with respect to the ophthalmic apparatus according to the exemplary embodiment.

It is possible to create a computer-readable non-temporary recording medium on which such a program is recorded. It is possible to combine this recording medium with any of the items described with respect to the ophthalmic apparatus according to the exemplary embodiment. The non-temporary recording medium may be in any form, and examples thereof include a magnetic disk, an optical disk, a magneto-optical disk, and a semiconductor memory.

An exemplary embodiment can provide a method of controlling an ophthalmic apparatus including an imaging unit that photographs the eye and a processor. For example, the ophthalmic apparatus 1000 (1500) includes an imaging unit (optical system, image sensor, camera, etc.) for photographing the anterior eye portion, and a processor (one or more). Further, the ophthalmic apparatus 2000 includes an anterior ocular segment observation system 5 that functions as an imaging system and a computer provided with a processor. The ophthalmic apparatus according to this aspect does not have to include an OCT unit.

In the control method according to the exemplary embodiment, in the first control step, the photographing unit is controlled in order to acquire a captured image of the eye after removing the ortho-K lens. In the second control step, the processor is controlled to receive OCT data acquired by applying optical coherence tomography to the fundus of the eye. Here, the processor accepts OCT data, for example, by controlling a communication device or a drive device. The data reception will be described later. In the third control step, the processor is controlled to analyze the captured image in order to acquire the corneal shape data of the eye. In the fourth control step, the processor is controlled to analyze the OCT data in order to acquire the fundus shape data of the eye. In the fifth control step, the processor is controlled to create an eyeball model based on at least the corneal shape data and the fundus shape data. In the sixth control step, the processor is controlled to perform a first evaluation of the effect of the ortho-K lens on the eye, at least based on the eye model.

It is possible to combine any of the matters described with respect to the ophthalmic device according to the exemplary embodiment with such a control method of the ophthalmic device.

It is possible to provide a program for causing an ophthalmic apparatus including a computer to execute a control method according to an exemplary embodiment. It is possible to combine this program with any of the items described with respect to the ophthalmic apparatus according to the exemplary embodiment.

It is possible to create a computer-readable non-temporary recording medium on which such a program is recorded. It is possible to combine this recording medium with any of the items described with respect to the ophthalmic apparatus according to the exemplary embodiment.

An exemplary embodiment can provide a method of controlling an ophthalmic apparatus including an OCT unit that applies OCT to the fundus and a processor. For example, the ophthalmic apparatus 1000 (1500) includes an OCT unit (optical system, image sensor, drive mechanism, processor, etc.) that applies OCT to the fundus, and (one or more) processors. Further, the ophthalmic apparatus 2000 includes an OCT unit 300 and a computer including a processor.

In the control method according to the exemplary embodiment, in the first control step, the processor is controlled in order to receive the captured image obtained by photographing the eye after removing the ortho-K lens. Here, the processor accepts captured images by, for example, controlling a communication device or a drive device. The data reception will be described later. In the second control step, the OCT unit is controlled in order to acquire OCT data of the fundus of the eye. In the third control step, the processor is controlled to analyze the captured image in order to acquire the corneal shape data of the eye. In the fourth control step, the processor is controlled to analyze the OCT data in order to acquire the fundus shape data of the eye. In the fifth control step, the processor is controlled to create an eyeball model based on at least the corneal shape data and the fundus shape data. In the sixth control step, the processor is controlled to perform a first evaluation of the effect of the ortho-K lens on the eye, at least based on the eye model.

It is possible to combine any of the matters described with respect to the ophthalmic device according to the exemplary embodiment with such a control method of the ophthalmic device.

It is possible to provide a program for causing an ophthalmic apparatus including a computer to execute a control method according to an exemplary embodiment. It is possible to combine this program with any of the items described with respect to the ophthalmic apparatus according to the exemplary embodiment.

It is possible to create a computer-readable non-temporary recording medium on which such a program is recorded. It is possible to combine this recording medium with any of the items described with respect to the ophthalmic apparatus according to the exemplary embodiment.

According to the control method, program, or recording medium according to the exemplary embodiment, it is possible to have an ophthalmic apparatus including at least one of an imaging unit and an OCT unit and a processor execute a suitability determination of an ortho-K lens.

<Other aspects>
In the above exemplary embodiment, an ophthalmic apparatus including an imaging function (imaging unit, OCT unit) has been described, but the embodiment is not limited thereto. For example, the ophthalmic information processing apparatus described below is a computer that receives an image of an eye acquired by another ophthalmic apparatus having a photographing function and executes a series of processes.

The ophthalmic information processing device according to the exemplary embodiment is, for example, a personal computer, a server provided on a local area network (LAN), a server (cloud server, etc.) provided on a wide area network (WAN), or another. It may include a computer in the form of.

FIG. 13 shows a configuration of an ophthalmic information processing device according to an exemplary embodiment. The ophthalmic information processing apparatus 3000 includes a data reception unit 3010, a captured image analysis unit 3020, an OCT data analysis unit 3030, an eyeball model creation unit 3040, an evaluation unit 3050, and a control unit 3060.

The data receiving unit 3010 receives data acquired by another ophthalmic apparatus. The data receiving unit 3010 includes, for example, either a communication device or a drive device.

The communication device of the data receiving unit 3010 receives data from, for example, another ophthalmic device via a network. Alternatively, the communication device of the data receiving unit 3010 receives data stored in a medical database (for example, an electronic medical record system, an image archiving system, etc.) from another ophthalmic device via a network.

The drive device of the data receiving unit 3010 reads the data acquired by another ophthalmic device and recorded on the recording medium from the recording medium.

The data receiving unit 3010 receives the captured image of the eye after removing the ortho-K lens and the OCT data acquired by applying optical coherence tomography to the fundus of the eye. Typically, the captured image and OCT data received by the data receiving unit 3010 are stored in a storage device (not shown), the captured image is provided to the captured image analysis unit 3020 by the control unit 3060, and the OCT data is controlled. It is provided to the OCT data analysis unit 3030 by the unit 3060.

The captured image analysis unit 3020 is configured to execute the same data processing as the processor of the corneal shape measuring unit 1010 of the ophthalmic apparatus 1000 (1500) (the same data processing as the first captured image analysis unit 2231 of the ophthalmic apparatus 2000). It functions to analyze the photographed image of the eye after removing the ortho-K lens and acquire the corneal shape data.

The OCT data analysis unit 3030 is configured to execute the same data processing as the processor of the fundus shape measuring unit 1020 of the ophthalmic apparatus 1000 (1500) (the same data processing as the OCT data analysis unit 2234 of the ophthalmic apparatus 2000). It functions to analyze the OCT data of the fundus of the eye and acquire the fundus shape data.

The eye model creating unit 3040 is configured to execute the same data processing as the eye model creating unit 1030 of the ophthalmic apparatus 1000 (1500) (data processing similar to the eye model creating unit 2235 of the ophthalmic apparatus 2000). It functions to create an eyeball model based on at least the corneal shape data acquired by the captured image analysis unit 3020 and the fundus shape data acquired by the OCT data analysis unit 3030.

The evaluation unit 3050 is configured to execute the same data processing as the evaluation unit 1040 of the ophthalmic apparatus 1000 (1500) (the same data processing as the first evaluation unit 2236 of the ophthalmic apparatus 2000), and is an eyeball model creation unit. It functions to perform a first assessment of the effect of the Ortho-K lens on the eye, at least based on the eye model created by 3040.

The control unit 3060 controls each unit of the ophthalmic information processing apparatus 3000. The control unit 3060 includes a processor that operates according to the control program.

According to the ophthalmic information processing apparatus 3000 configured in this way, it is possible to automatically determine the suitability of the ortho-K lens based on the captured image of the eye acquired by another ophthalmic apparatus.

In an exemplary embodiment, the ophthalmic information processing device 3000 can be installed on a network and can be configured to process data (captured images, OCT data, etc.) from a plurality of ophthalmic devices. As a result, the ophthalmic information processing apparatus 3000 can perform the evaluation process intensively (unifiedly) without providing the ortho-K lens evaluation function in each ophthalmic apparatus. According to this configuration, it becomes possible to widely provide the evaluation service of the ortho-K lens.

It is possible to combine such an ophthalmic information processing apparatus 3000 with any of the items described with respect to the ophthalmic apparatus (1000, 1500, 2000) according to the exemplary embodiment.

An exemplary embodiment can provide a method of controlling an ophthalmic information processing device including a processor. For example, the ophthalmic information processing device 3000 includes (one or more) processors. The same applies to the computer 9 of the ophthalmic apparatus 2000.

In the control method according to the exemplary embodiment, in the first control step, the processor is controlled in order to receive the captured image obtained by photographing the eye after removing the ortho-K lens. In the second control step, the processor is controlled to apply OCT to the fundus of the eye and receive the acquired OCT data. These data receptions are realized, for example, by the processor controlling a communication device or a drive device. In the third control step, the processor is controlled to analyze the captured image in order to acquire the corneal shape data of the eye. In the fourth control step, the processor is controlled to analyze the OCT data in order to acquire the fundus shape data of the eye. In the fifth control step, the processor is controlled to create an eyeball model based on at least the corneal shape data and the fundus shape data. In the sixth control step, the processor is controlled to perform a first evaluation of the effect of the ortho-K lens on the eye, at least based on the eye model.

It is possible to combine any of the matters described with respect to the ophthalmic apparatus according to the exemplary embodiment with the control method of such an ophthalmic information processing apparatus. Further, it is possible to combine any of the items described with respect to the ophthalmic information processing device according to the exemplary embodiment with the control method of such an ophthalmic information processing device.

A program can be provided that causes a computer to execute a control method according to an exemplary embodiment. It is possible to combine this program with any of the items described with respect to the ophthalmic apparatus according to the exemplary embodiment. It is also possible to combine this program with any of the items described for the ophthalmic information processing apparatus according to the exemplary embodiment.

It is possible to create a computer-readable non-temporary recording medium on which such a program is recorded. It is possible to combine this recording medium with any of the items described with respect to the ophthalmic apparatus according to the exemplary embodiment. In addition, it is possible to combine this recording medium with any of the items described with respect to the ophthalmic information processing apparatus according to the exemplary embodiment.

According to the control method, program, or recording medium according to the exemplary embodiment, it is possible to make the computer execute the suitability determination of the ortho-K lens. As a result, it is possible to actually obtain the expected refraction correction effect and the material for judging what the refraction state of the peripheral vision is (that is, whether or not the Ortho K lens was mounted in an appropriate position at night). It becomes possible to directly or indirectly provide the user (doctor, etc.) with the material for determining whether or not the lens is used.

<Modification example>
Some of the embodiments described above are merely examples of embodiments of the present invention. Therefore, it is possible to make arbitrary modifications (omission, substitution, addition, etc.) within the scope of the gist of the present invention.

For example, in the first aspect, an eye model creation using the method disclosed in Japanese Patent Application No. 2019-005431 by the applicant, or an eyeball model creation using the method disclosed in Japanese Patent Application No. 2019-005434 by the present applicant. However, the eyeball model creation method applicable to the embodiment is not limited to the above-mentioned method.

As a modified example of creating an eyeball model, a method using the fundus tilt correction disclosed in US Patent Application No. 16 / 146,144 by the present applicant will be described below. The apparent tilt of the fundus changes depending on the alignment state when the measurement or imaging for acquiring the fundus shape data is performed. In this modification, the tilt angle (direction of the fundus shape data) of the fundus shape data is corrected by using the alignment information, and the corrected fundus shape data is used for the evaluation of the ortho-K lens. It is also possible to apply the same inclination correction to the corneal shape data.

The ophthalmologic apparatus of this modification typically uses an OCT scan to acquire fundus shape data and corrects the tilt angle of the fundus shape data from the alignment information during the fundus OCT scan. Specifically, the ophthalmic apparatus of this modified example includes an alignment unit and an eyeball model creation unit capable of correcting fundus inclination, in addition to the corneal shape measuring unit, the fundus shape measuring unit and the evaluation unit according to the above aspect. .. The alignment unit has an arbitrary configuration for performing alignment, for example, XY alignment using a pupil image (corneal reference), Z alignment using optical teco (corneal reference), and XYZ alignment using stereo photography (corneal reference). Perform pupillary), 3D alignment (corneal reference) using Pulkinye image and stereo imaging, or other methods of alignment. The eyeball model creation unit is a processor that corrects the tilt angle of the fundus shape data (direction of the fundus shape data, tilt angle of the OCT image of the fundus) based on the alignment result (typically representing the misalignment) by the alignment unit. (Inclination angle correction unit) is included, and an eyeball model is created based on at least the fundus shape data and the corneal shape data in which the inclination angle is corrected.

The tilt angle correction unit of this modification may be configured to obtain the tilt angle of the fundus (fundus shape data) from the OCT image of the fundus and correct the tilt angle using the alignment result. In this example, the alignment unit aligns the OCT optical system with reference to a predetermined part of the eye. The processor (image forming unit) forms a tomographic image of the fundus based on the OCT data collected by the aligned OCT optical system. The tilt angle correction unit includes a processor (first calculation unit) that calculates the tilt angle (first tilt angle) of this tomographic image and a processor (second calculation unit) that corrects the first tilt angle based on the alignment result. Including. The output information from the second calculation unit is called the second tilt angle.

The alignment unit of this modification may be configured to obtain the deviation between the measurement optical axis of the OCT optical system and the eyeball optical axis as the alignment deviation. That is, the ophthalmic apparatus of this modification may include a processor (deviation amount specifying unit) that specifies the amount of deviation between the measurement optical axis of the OCT optical system on which alignment is executed and the optical axis of the eyeball of the eye. The second calculation unit can correct the first inclination angle based on the specified deviation amount and obtain the second inclination angle.

The ophthalmic apparatus of this modification may be configured so as not to correct the first tilt angle when the measurement optical axis and the eyeball optical axis substantially coincide with each other. That is, the second calculation unit of this modification determines whether the measurement optical axis and the eyeball optical axis substantially match (for example, the amount of deviation between the measurement optical axis and the eyeball optical axis is included in a predetermined allowable range. If it is determined that they are substantially the same, the first inclination angle can be output as it is as the second inclination angle.

The ophthalmic apparatus of this modification may be configured to obtain an XY shift amount (for example, a vector indicating an alignment deviation in the XY direction) between the measurement optical axis and the eyeball optical axis and perform tilt angle correction. That is, the deviation amount specifying unit may be configured to specify the displacement amount of the eyeball optical axis with respect to the measurement optical axis in the direction intersecting the measurement optical axis (XY direction) as the shift amount. The second calculation unit determines whether the eyeball optical axis is shifted with respect to the measurement optical axis (for example, determines whether the shift amount is included in a predetermined allowable range), and the eyeball optical axis is determined with respect to the measurement optical axis. When it is determined that the gear is shifting, the first tilt angle can be corrected based on the specified shift amount to obtain the second tilt angle.

As a configuration example for tilt angle correction based on the XY shift amount, the second calculation unit corrects the first tilt angle according to a linear equation using the specified shift amount as a variable to obtain the second tilt angle. It may be configured.

The ophthalmic apparatus of this modification may be configured to obtain the tilt amount between the measurement optical axis and the eyeball optical axis and perform tilt angle correction. That is, the deviation amount specifying unit may be configured to specify the angle formed by the eyeball optical axis with respect to the measurement optical axis as the tilt amount. The second calculation unit determines whether the eyeball optical axis is tilted with respect to the measurement optical axis (for example, determines whether the tilt amount is included in a predetermined allowable range), and the eyeball optical axis is relative to the measurement optical axis. When it is determined that the tilt is tilted, the first tilt angle can be corrected based on the specified tilt amount to obtain the second tilt angle.

As a configuration example for tilt angle correction based on the tilt amount, the second calculation unit is configured to correct the first tilt angle and obtain the second tilt angle according to a linear equation using the specified tilt amount as a variable. May be done.

When the tilt angle correction is performed using both the XY shift amount and the tilt amount, the second calculation unit is obtained by linearly combining the linear expression with the shift amount as a variable and the linear expression with the tilt amount as a variable. It may be configured to correct the first tilt angle according to the coupling formula to obtain the second tilt angle.

The ophthalmic apparatus of this modification may include a fixation projection system that projects a fixation flux onto the fundus during a fundus OCT scan. In this case, the visual axis of the eye is typically used as the optical axis of the eyeball.

When alignment is performed using the Pulkinje image and stereo photography, the alignment unit is an optical system (XY alignment system 2) that projects alignment light onto the eye, as in the configuration disclosed in Japanese Patent Application Laid-Open No. 2017-74115. A moving mechanism (200) that relatively moves the eye and the OCT optical system, and two or more imaging units (typically two) that photograph the anterior segment of the eye on which the alignment light is projected from different directions. Includes one anterior segment camera) and a processor (positioning unit). By analyzing two or more captured images obtained by two or more imaging units, the positioning unit determines the position of the reflected image of the cornea by the alignment light (first position, typically the position of the Purkinje image). The position of a predetermined part (second position, typically the position of the corneal apex) used as the reference for alignment is specified, and the movement target position of the OCT optical system is determined based on the specified first position and second position. decide. The processor (control unit) controls the movement mechanism so as to move the OCT optical system to the movement target position. Typically, the alignment is done so as to cancel the deviation between the first position and the second position. By repeating such a series of processes, it is possible to perform an operation (tracking) in which the OCT optical system is made to follow the movement of the eye. Alternatively, the deviation between the first position and the second position may be monitored, and the OCT optical system may be moved when the deviation exceeds a predetermined allowable range.

The first calculation unit of this modified example can calculate the fundus tilt angle based on the drawing position of a predetermined layered tissue in the OCT image (tomographic image) of the fundus. That is, the first calculation unit specifies the position of the image region of the predetermined layer region at the right end of the frame of the fundus tomographic image, specifies the position of the image region at the left end of the frame, and the vertical direction of the two specified positions. The distance in is calculated, this distance is converted to the actual size (d), the horizontal distance of the frame is converted to the actual size (c), and arctan (| d | / c) is calculated as the first tilt angle. It may be configured as follows.

Here, the conversion of the horizontal distance of the frame to the actual size is performed based on predetermined data. For example, the first calculation unit may be configured to convert the horizontal distance of the frame of the tomographic image into the actual size based on the radius of curvature of the cornea, the refractive power of the eye, and the axial length. Alternatively, the first calculation unit determines the horizontal distance of the frame of the tomographic image based on the radius of curvature of the cornea, the position of the focusing lens (87) of the OCT optical system at the time of fundus OCT scan, and the axial length. It may be configured to be converted to actual dimensions. Here, the radius of curvature of the cornea (corneal curvature) is obtained using a keratometer, a corneal topographer, or a configuration equivalent to any of these. The ocular refractive power is obtained using a refractometer or an equivalent configuration. The axial length is obtained using an OCT axial length measuring device, an ultrasonic axial length measuring device, or a configuration equivalent to any of these. Measurements on the parameters used to convert the horizontal distance of the frame to actual dimensions are made by the ophthalmic device or other ophthalmic device. It should be noted that any one of the plurality of parameters used for converting the horizontal distance of the frame into the actual size may be a standard value based on a model eye or the like. Alternatively, the first calculation unit is configured to convert the horizontal distance of the frame into the actual size by multiplying the horizontal distance of the frame of the tomographic image by a preset pixel spacing value. May be good.

Specific examples of the ophthalmic apparatus including at least one of the several configurations described above will be described. FIG. 14 shows a configuration example of the ophthalmic apparatus according to this example. The ophthalmic apparatus 4000 is the same as the corneal shape measuring unit 1010, the fundus shape measuring unit 1020, the evaluation unit 1040, and the control unit 1050 of the ophthalmic apparatus 1000 according to the first aspect, respectively, the corneal shape measuring unit 4010 and the fundus shape measuring unit. In addition to the 4020, the evaluation unit 4040, and the control unit 4050, the eyeball model creation unit 4030 including the tilt angle correction unit 4031 and the alignment unit 4060 are included. Hereinafter, unless otherwise specified, the terms, symbols, etc. in the above-described embodiments shall be applied mutatis mutandis.

Each of the corneal shape measuring unit 4010, the fundus shape measuring unit 4020, the evaluation unit 4040, and the control unit 4050 is realized by, for example, the corresponding element in the third aspect, but is not limited thereto.

The alignment unit 4060 aligns the fundus shape measuring unit 4020 (its optical system, for example, the OCT optical system 8) with respect to the eye. As described above, the alignment unit 4060 may include, for example, any of the following elements (groups): XY alignment system 2 for performing corneal-based XY alignment using the Pukinje image; optical optics were used. Z alignment system for performing Z alignment based on the cornea 1; Two anterior segment cameras for performing XYZ alignment based on the pupil using stereo imaging (see, for example, Japanese Patent Application Laid-Open No. 2017-74115); An alignment optical projection optical system (XY alignment system 2) and two anterior segment cameras (see, for example, Japanese Patent Application Laid-Open No. 2017-74115) for performing corneal-based three-dimensional alignment using stereo imaging. The alignment unit 4060 outputs information indicating the misalignment as the alignment result.

The tilt angle correction unit 4031 of the eyeball model creation unit 4030 corrects the tilt angle of the fundus shape data based on the alignment result output from the alignment unit 4060. The process executed by the tilt angle correction unit 4031 will be described later. The eyeball model creation unit 4030 creates an eyeball model based on at least the fundus shape data whose tilt angle is corrected by the tilt angle correction unit 4031 and the corneal shape data acquired by the corneal shape measurement unit 4010. The eyeball model creation process based on at least the fundus shape data and the corneal shape data may be the same as that in any of the above-described embodiments.

Some examples of the processing executed by the tilt angle correction unit 4031 and some examples of various processing incidental thereto will be described. Hereinafter, the configuration of the third aspect (particularly, FIGS. 6 to 8) will be referred to. The alignment unit 4060A of this example shown in FIG. 15 is an example of the alignment unit 4060 of FIG. 14, and is the XY alignment system 2 in the third aspect and two front eye cameras similar to those of JP-A-2017-74115. Includes 4061 (4061A, 4061B).

When the main control unit 211 turns on the XY alignment light source 21, a Purkinje image is formed on the anterior segment of the eye. The Pulkinje image is formed at a position deviated from the apex of the cornea to the inner side in the axial direction (Z direction) by a distance of half the radius of curvature of the cornea. The anterior segment to which the alignment luminous flux is projected is photographed substantially simultaneously by the two anterior segment cameras 4061, and the two captured images acquired thereby are provided for the processing of this example.

The tilt angle correction unit 4031 analyzes each of the two captured images, identifies the Purkinje image, and identifies the position thereof. The position of the Purkinje image may include at least a position in the X direction (X coordinate) and a position in the Y direction (Y coordinate), and may further include a position in the Z direction (Z coordinate). Typically, the two captured images are acquired by imaging from two positions off the optical axis of the objective lens 51, respectively. When the XY alignment is substantially aligned, the two Purkinje images in the two captured images are both drawn at positions corresponding to the optical axis of the objective lens 51.

Since the viewing angle (tilt angle of the objective lens 51 with respect to the optical axis) of the two front eye cameras 4061 is known and the shooting magnification is also known, based on the positions of the two Pulkinje images in the two shot images, The relative position (three-dimensional position in the real space) of the Pulkinje image with respect to the ophthalmic apparatus 4000 (each front eye camera 4061) can be obtained. Further, based on the relative position (displacement amount) between the pupil region and the Purkinje image in one captured image and the relative position (displacement amount) between the pupil region and the Purkinje image in the other captured image, the pupil and the front The relative position between the Purkinje image formed in the eye (for example, the amount of eccentricity between the cornea and the pupil) can be obtained.

The tilt angle correction unit 4031 can identify the position in the captured image corresponding to a predetermined feature point of the anterior segment by analyzing each captured image obtained by the anterior segment camera 4061. For example, the tilt angle correction unit 4031 specifies the pupil region based on the distribution of the pixel values (luminance values) of the captured image, and specifies the center position (center of the pupil, center of gravity of the pupil). Further, the tilt angle correction unit 4031 identifies the three-dimensional position of the pupil center of the eye based on the positions (and the imaging magnification) of the two front eye cameras 4061 and the positions of the pupil centers in the two captured images. can do. This process typically utilizes an operation using trigonometry as described in JP-A-2017-74115.

The tilt angle correction unit 4031 determines the movement target position of the device optical system based on the specified Purkinje image position and the specified pupil center position. For example, the tilt angle correction unit 4031 can obtain the difference between the position of the Purkinje image and the center position of the pupil, and can determine the movement target position so that the obtained difference satisfies the predetermined alignment completion condition. The main control unit 211 can perform three-dimensional alignment by controlling the movement mechanism 200 based on the movement target position determined by the tilt angle correction unit 4031.

The tilt angle correction unit 4031 specifies the amount of deviation between the measurement optical axis of the aligned OCT optical system 8 and the optical axis of the eyeball. The optical axis of measurement in this example is the optical axis of the objective lens 51. The optical axis of the eyeball may be any axis that passes through the eyeball, such as the visual axis and the optical axis. When performing an OCT scan while projecting a fixation light flux onto the eye, the visual axis can be adopted as the optical axis of the eyeball. The tilt angle correction unit 4031 of this example specifies the amount of deviation between the measurement optical axis and the visual axis of the eye.

The amount of deviation typically includes one or both of a shift amount and a tilt amount between the measurement optical axis and the eyeball optical axis (visual axis). The shift amount corresponds to the deviation amount of the optical axis of the eyeball in the direction (XY direction) orthogonal to the measurement optical axis (Z direction). The tilt amount corresponds to the angle formed by the measurement optical axis and the eyeball optical axis.

The tilt angle correction unit 4031 can obtain a shift amount (unit: millimeter) based on the amount of deviation between the position of the Purkinje image and a predetermined reference position. This reference position is typically the position of the measurement optical axis. The tilt angle correction unit 4031 obtains, for example, the difference in the position of the Pulkiner image with respect to the position of the measurement optical axis in the XY plane passing through the Pulkiner image (the XY plane defined by the position of the Z coordinate of the Pulkiner image) and shifts the amount. (Unit: millimeter).

The tilt angle correction unit 4031 can specify the tilt amount (unit: degree) based on the amount of deviation between the position of the Purkinje image and the center position of the pupil. The tilt angle correction unit 4031 specifies the direction of the eyeball optical axis (visual axis) based on, for example, the three-dimensional position of the Purkinje image and the three-dimensional position of the center of the pupil, and the direction of the specified visual axis and the measurement optical axis. The tilt amount can be obtained by finding the angle between the two.

The tilt angle correction unit 4031 can determine at least the amount of deviation generated during the OCT scan. For example, the tilt angle correction unit 4031 sequentially analyzes the time-series captured images obtained by the anterior segment camera 4061 to obtain the time change of the position of the Pulkinje image and the time change of the position of the center of the pupil. The time change of the amount can be acquired in real time.

The tilt angle correction unit 4031 converts the distance specified in the OCT image (tomographic image) of the fundus Ef formed by the image forming unit 222 into a value corresponding to the actual size. The tilt angle correction unit 4031 can convert the distance in the Z direction in the tomographic image based on the pixel spacing value Δp (unit: micrometer / pixel) in the eyeball tissue peculiar to the device optical system. The tilt angle correction unit 4031 can convert the distance (OCT scan range) in the XY direction in the tomographic image based on the size information generated as follows.

For example, the tilt angle correction unit 4031 generates size information using model eye data, which is standard value data, and measured values of optical characteristics of the eye. Measurements of the optical properties of the eye include, for example, at least one of the radius of curvature of the cornea, the degree of refractive error of the eye, and the axial length of the eye. The radius of curvature of the cornea can be obtained using the kerato measurement system 3. The ocular refractive power can be obtained by using the reflex measurement projection system 6 and the reflex measurement light receiving system 7. The axial length can be obtained using the OCT optical system 8. Such processing by the tilt angle correction unit 4031 may be the same as the processing disclosed in, for example, Japanese Patent Application Laid-Open No. 2016-43155.

The tilt angle correction unit 4031 generates size information using the model eye data and the measured value acquired by the ophthalmic apparatus 4000. In this size information generation process, among the parameters included in the model eye data, the measured values acquired by the ophthalmic apparatus 4000 are used for the parameters that can be measured by the ophthalmic apparatus 4000.

In this example, the tilt angle correction unit 4031 can generate size information by performing magnification correction based on the acquired measured value. For example, the tilt angle correction unit 4031 obtains the magnification of the eyeball optical system and generates size information indicating the size of one pixel in the tomographic image of the eye from the obtained magnification.

As a specific example, first, the tilt angle correction unit 4031 calculates the magnification of the eye to be inspected by the eyeball optical system based on the measured value of the optical characteristics of the eye. In this example, the imaging magnification is obtained in consideration of both the magnification by the eye and the magnification by the OCT optical system 8. Here, the OCT optical system 8 has a general configuration in which an objective lens 51, a photographing diaphragm (not shown), a magnification lens (focusing lens 87), and a relay lens 85 are arranged on the optical axis in order from the eye side. Suppose you have.

When the inclination angle correction unit 4031 is the measured value (corneal refractive index) at the apex of the cornea, the tilt angle correction unit 4031 converts it into the refractive index (pupil refractive index) in the pupil, if necessary. This calculation can be performed, for example, based on the spectacle wearing distance and the distance from the corneal apex to the entrance pupil, as in the conventional case.

Next, the tilt angle correction unit 4031 calculates the imaging position by the objective lens 51. This calculation can be performed, for example, by using Newton's equation based on the pupil dioptric power, the focal length of the objective lens 51, and the distance from the entrance pupil to the anterior focal length of the objective lens 51.

Next, the tilt angle correction unit 4031 calculates the shooting magnification by the variable magnification lens (focusing lens). This calculation can be performed, for example, by solving a quadratic equation expressing the relationship between the calculation result of the imaging position by the objective lens 51, the focal length of the variable magnification lens, the distance between the principal points, and the object image distance for the photographing magnification. it can.

Next, the tilt angle correction unit 4031 calculates the ejection angle from the objective lens 51. This calculation can be performed based on, for example, the calculation result of the photographing magnification, the distance from the rear principal point of the objective lens 51 to the photographing aperture, and the focal length of the objective lens 51. At this time, the ejection angle is calculated so that the height of the image on the detection surface of the image becomes a predetermined value. This predetermined value is, for example, −0.1 mm (a negative sign indicates that an image is formed downward from the optical axis).

Next, the tilt angle correction unit 4031 calculates the angle of incidence on the objective lens 51 so that the height of the image on the diaphragm surface of the photographing aperture becomes the above-mentioned predetermined value. This calculation can be performed based on, for example, the calculation result of the ejection angle from the objective lens 51, the entrance pupil, and the angular magnification of the photographing diaphragm.

Next, the tilt angle correction unit 4031 calculates the radius of curvature of the posterior surface of the cornea of the eye. This calculation can be performed, for example, based on the measured value of the corneal curvature (curvature of the anterior surface of the cornea) measured using the kerato measurement system 3 and the ratio of the curvatures of the anterior and posterior surfaces of the cornea. As the ratio of the curvatures, for example, the value of the model eye data can be used. The curvature (radius of curvature) of the posterior surface of the cornea Cr may be measured using the OCT optical system 8.

Next, the tilt angle correction unit 4031 calculates the distance between the far point and the object (corneal apex). This calculation can be performed, for example, based on the refractive power at the apex of the cornea and the spectacle wearing distance.

Next, the tilt angle correction unit 4031 calculates the distance from the posterior surface of the crystalline lens of the eye to the retinal surface (fundus surface). This calculation can be performed, for example, by measuring the curvature (radius of curvature) of the cornea Cr and tracing the paraxial ray based on the calculated value. At this time, for the optical constant of the eyeball, for example, a value of model eye data can be used.

Next, the optical constant of the eyeball optical system of the eye is determined. As the optical constants of the eye, for example, the measured value of the curvature (radius of curvature) of the cornea, the calculation result, the measured value of the refractive index, and the measured value of the axial length are adopted. Further, as the radius of curvature of the retinal surface (fundus surface), a value calculated from the fundus shape data or a value half of the measured value of the axial length can be adopted. Further, as the distance from the posterior surface of the crystalline lens to the retina (fundus surface), the measured value obtained by using the OCT optical system 8 or the standard value of the distance from the anterior surface of the cornea to the posterior surface of the crystalline lens (value of model eye data) is used as the axial axis. Use the value subtracted from the length measurement value.

After the optical constant of the eye is determined, the tilt angle correction unit 4031 calculates the height of the image on the retinal surface (fundus surface) obtained from the fundus shape data. This calculation can be performed, for example, by ray tracing using the determined optical constant and the calculation result of the angle of incidence on the objective lens 51.

Finally, the tilt angle correction unit 4031 is based on the calculation result of the image height on the retinal surface, the calculation result of the image height on the detection surface, the relay magnification by the relay lens (the influence of the photographing optical system, etc.), and the like. Calculate the magnification. This magnification takes into consideration the magnification of the eyeball optical system and the magnification of the photographing optical system.

The tilt angle correction unit 4031 obtains the length (unit: micrometer / pixel) of one pixel in the tomographic image as size information from the obtained magnification. For example, the tilt angle correction unit 4031 includes table information in which the lengths of one pixel are associated with each of the plurality of magnifications in advance, and by referring to the table information, 1 in the fundus image is obtained from the obtained magnification. The length of each of the vertical and horizontal dimensions of the pixel can be obtained. It is also possible to use graph information in which a continuous change in the magnification value and a change in the size of one pixel are associated with each other instead of the table information regarding a plurality of discrete magnification values.

The tilt angle correction unit 4031 calculates the tilt angle of the fundus Ef drawn on the tomographic image formed by the image forming unit 222. The tilt angle correction unit 4031 obtains, for example, the tilt angle of a predetermined layer region specified by known segmentation. Predetermined layer regions include the inner limiting membrane, nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer, outer nuclear layer, outer limiting membrane, photoreceptor layer, retinal pigment epithelial layer, and the like. ..

The tomographic image of the fundus Ef acquired in this example is, for example, the B-scan image IMG shown in FIG. 2E described in the first aspect. Hereinafter, FIG. 2E will be referred to. In the frame left end LT of the tomographic image IMG, the distance in the vertical direction from the frame upper end UT to the image region of the portion corresponding to a predetermined layer region (for example, nerve fiber layer) in the fundus Ef is defined as L1. Similarly, in the frame right end RT of the tomographic image IMG, the distance in the vertical direction from the frame upper end UT to the image region of the portion corresponding to the layer region is defined as R1. The tilt angle correction unit 4031 sets the pixel spacing value (pixel spacing correction value) Δp to the vertical difference (| R1-L1 |) of the image region of the relevant portion in the frame left end LT and the frame right end RT in the tomographic image IMG. By multiplying, the value | d | corresponding to the actual size is obtained for the difference (| R1-L1 |).

Next, the tilt angle correction unit 4031 converts the horizontal distance H1 of the frame of the tomographic image IMG corresponding to the OCT scan range into a value c corresponding to the actual size for the distance H1 using the above size information.

The tilt angle correction unit 4031 obtains the tilt angle g0 (unit: degree) of the tomographic image according to the following equation (1).

g0 = arctan (| d | / c) ・ ・ ・ (1)

The tilt angle correction unit 4031 can calculate the fundus tilt angle by correcting the tilt angle of the tomographic image according to the amount of deviation specified in the above-mentioned procedure.

Specifically, the tilt angle correction unit 4031 executes a determination regarding a specific result of the deviation amount. The tilt angle correction unit 4031 calculates the fundus tilt angle based on the obtained determination result.

<When the measurement optical axis and the eyeball optical axis are approximately the same>
As shown in FIG. 16, when it is determined that the measurement optical axis (optical axis of the objective lens 51) Oax and the eyeball optical axis (visual axis) Ex are substantially the same, the tilt angle correction unit 4031 performs a tomographic image. It is output as the fundus tilt angle g1 without correcting the tilt angle g0 of. That is, the tilt angle correction unit 4031 outputs the tilt angle g0 of the tomographic image as the fundus tilt angle g1 as shown in the following equation (2).

g1 = g0 = arctan (| d | / c) ... (2)

<When the optical axis of the eyeball is shifted with respect to the optical axis of measurement>
As shown in FIG. 17, when it is determined that the eyeball optical axis Ex is shifted with respect to the measurement optical axis Oax, the tilt angle correction unit 4031 determines the tilt angle of the tomographic image based on the specified shift amount ds. The fundus tilt angle g1 is obtained by correcting g0.

The tilt angle correction unit 4031 obtains the correction angle φ1 according to a linear equation with the shift amount ds as a variable as shown in the following equation (3), and as shown in the following equation (4), the obtained correction angle. The fundus tilt angle g1 is obtained by correcting the tilt angle g0 of the tomographic image using φ1. In the formula (3), α1 and c1 are constants, and can be obtained by using, for example, model eye data.

φ1 = α1 × ds + c1 ・ ・ ・ (3)
g1 = g0-φ1 ... (4)

<When the optical axis of the eyeball is tilted with respect to the optical axis of measurement>
As shown in FIG. 18, when it is determined that the eyeball optical axis Ex is tilted with respect to the measurement optical axis Oax, the tilt angle correction unit 4031 is based on the tilt amount dt specified by the tilt angle correction unit 4031. By correcting the tilt angle g0 of the tomographic image, the fundus tilt angle g1 is obtained.

The tilt angle correction unit 4031 obtains the correction angle φ2 according to a linear equation with the tilt amount dt as a variable as shown in the following equation (5), and as shown in the following equation (6), the obtained correction angle. The fundus tilt angle g1 is obtained by correcting the tilt angle g0 of the tomographic image using φ2. In the formula (5), α2 and c2 are constants, and can be obtained by using, for example, model eye data.

φ2 = α2 × dt + c2 ・ ・ ・ (5)
g1 = g0-φ2 ・ ・ ・ (6)

<When the optical axis of the eyeball is shifted and tilted with respect to the optical axis of measurement>
As shown in FIG. 19, when it is determined that the eyeball optical axis Ex is shifted and tilted with respect to the measurement optical axis Oax, the tilt angle correction unit 4031 determines the specified shift amount ds and tilt amount dt. The fundus tilt angle g1 is obtained by correcting the tilt angle g0 of the tomographic image based on.

In the range where the shift amount ds and the tilt amount dt are small, the tilt angle correction unit 4031 obtains the correction angle φ3 according to the equation with the shift amount ds and the tilt amount dt as variables as shown in the following equation (7), and the following As shown in the equation (8) of the above, the fundus inclination angle g1 is obtained by correcting the inclination angle g0 of the tomographic image using the obtained correction angle φ3. In some examples, equation (8) is a combination equation obtained by linearly combining an equation for obtaining the correction angle of the shift amount and an equation for obtaining the correction angle of the tilt amount. In the formula (7), α3, α4 and c3 are constants and can be obtained by using, for example, model eye data.

φ3 = α3 × ds + α4 × dt + c3 ・ ・ ・ (7)
g1 = g0-φ3 ・ ・ ・ (8)

In the above example, the OCT scan range is corrected using the ocular refractive power acquired by the reflex measurement optical system, but the eye is viewed from the position of the focusing lens 87 determined by the focus adjustment performed in preparation for the OCT scan. The refractive power may be specified and used for correction of the OCT scan range. In this case, the correspondence information that records the correspondence between the position of the focusing lens 87 and the refractive power of the eye can be used.

As described above, the tilt angle correction unit 4031 corrects the tilt angle (direction) of the fundus shape data obtained by the fundus shape measuring unit 4020 based on the alignment result by the alignment unit 4060. The eyeball model creating unit 4030 creates an eyeball model based on at least the corneal shape data acquired by the corneal shape measuring unit 4010 and the fundus shape data whose tilt angle is corrected by the tilt angle correction unit 4031. The evaluation unit 4040 can perform the first evaluation regarding the effect of the ortho-K lens on the eye, at least based on the eyeball model reflecting such a fundus tilt angle.

According to this example, the automatic suitability determination of the Ortho-K lens can be performed with higher accuracy. For example, even if there is a misalignment in the alignment when measuring the fundus shape for creating an eyeball model, an eyeball model that has been corrected to cancel the effect of this misalignment is created, and the first eye model is used. It is possible to make an evaluation.

Any of the matters described in this example can be combined with any of the ophthalmic apparatus, its control method, the ophthalmic information processing apparatus, its control method, the program, and the recording medium according to the exemplary embodiment.

1000, 1500 Ophthalmic device 1010 Corneal shape measurement unit 1020 Eyelid shape measurement unit 1021 OCT unit 1022 Eyeball shape data generation unit 1030 Eyeball model creation unit 1031 Front eye unit reference position identification unit 1032 Eye fundus reference position identification unit 1040 Evaluation unit 1041 Focus position identification Unit 1042 1st evaluation execution unit 1060 Specific site detection unit 1070 Feature point setting unit 2000 Ophthalmology device 5 Front eye observation system 221 Eye refractive force calculation unit 300 OCT unit 2231 1st captured image analysis unit 2232 Feature point setting unit 2233 2nd Evaluation unit 2234 OCT data analysis unit 2235 Eyeball model creation unit 2236 First evaluation unit 3000 Ophthalmology information processing device 3010 Data reception unit 3020 Photographed image analysis unit 3030 OCT data analysis unit 3040 Eyeball model creation unit 3050 Evaluation unit

Claims (23)

A corneal shape measuring unit that measures the corneal shape of the eye after removing the orthokeratology lens,
The fundus shape measuring unit for measuring the fundus shape of the eye,
An eyeball model creating unit that creates an eyeball model based on at least the corneal shape data acquired by the corneal shape measuring unit and the fundus shape data acquired by the fundus fundus shape measuring unit.
An ophthalmic apparatus comprising an evaluation unit that performs a first evaluation of the effect of the orthokeratology lens on the eye based on at least the eye model. The evaluation unit
A focal position specifying portion that specifies the focal position of a virtual ray incident on the peripheral portion of the fundus of the eyeball model,
Includes a first evaluation execution unit that executes the first evaluation based on the positional relationship between the focal position and the peripheral portion of the fundus.
The ophthalmic apparatus of claim 1. Further including an alignment unit for aligning the fundus shape measuring unit with respect to the eye.
The eyeball model creation unit
The tilt angle correction unit that corrects the tilt angle of the fundus shape data based on the alignment result by the alignment unit is included.
An eyeball model is created based on at least the corneal shape data and the fundus shape data in which the tilt angle is corrected.
The ophthalmic apparatus according to claim 1 or 2. The eyeball model creating unit creates an eyeball model by determining a relative position between the corneal shape data and the fundus shape data based on at least a predetermined anterior segment reference position and a fundus reference position.
The ophthalmic apparatus according to any one of claims 1 to 3. The eyeball model creating unit determines a relative position between the corneal shape data and the fundus shape data based on at least the corneal apex position as the anterior segment reference position and the fovea centralis position as the fundus reference position, and the eyeball. Create a model,
The ophthalmic apparatus of claim 4. The eyeball model creating unit creates an eyeball model by further determining a relative position between the corneal shape data and the fundus shape data based on predetermined axial length data.
The ophthalmic apparatus of claim 5. The eyeball model creating unit determines a relative position between the corneal shape data and the fundus shape data based on at least the pupil center position as the anterior eye region reference position and the fovea centralis position as the fundus reference position, and the eyeball. Create a model,
The ophthalmic apparatus of claim 4. The eyeball model creating unit creates an eyeball model by further determining a relative position between the corneal shape data and the fundus shape data based on predetermined axial length data and anterior chamber depth data.
The ophthalmic apparatus of claim 7. The eyeball model creating unit includes an anterior eye portion reference position specifying unit that analyzes the corneal shape data and specifies an anterior eye portion reference position.
The ophthalmic apparatus according to any one of claims 4 to 8. The fundus shape measuring unit
An OCT unit that generates OCT data by applying optical coherence tomography to the fundus of the eye,
Includes a fundus shape data generator that analyzes the OCT data and generates fundus shape data.
The eyeball model creating unit includes a fundus reference position specifying unit that analyzes the OCT data and specifies a fundus reference position.
The ophthalmic apparatus according to any one of claims 4 to 9. A specific site detection unit that detects a specific site of the eye,
It further includes a feature point setting unit that sets a feature point from the corneal shape data acquired by the cornea shape measurement unit.
The evaluation unit executes a second evaluation regarding the wearing state of the orthokeratology lens with respect to the eye based on the specific portion and the feature point.
The ophthalmic apparatus according to any one of claims 1 to 10. The feature point setting unit sets the feature point based on the approximate expression of the corneal shape data by the centrally symmetric expression.
The ophthalmic apparatus of claim 11. The feature point setting unit sets the center of the approximate expression as the feature point.
The ophthalmic apparatus of claim 12. The corneal shape measuring unit acquires the curvature distribution data or the radius of curvature distribution data of the cornea as the corneal shape data.
The ophthalmic apparatus according to any one of claims 1 to 13. The corneal shape measuring unit acquires the height distribution data of the cornea as the corneal shape data.
The ophthalmic apparatus according to any one of claims 1 to 13. A method of controlling an ophthalmic apparatus including an imaging unit that photographs the eye, an OCT unit that applies optical coherence tomography to the fundus, and a processor.
The imaging unit is controlled to acquire a captured image of the eye after the orthokeratology lens is removed.
The OCT unit is controlled to acquire OCT data of the fundus of the eye.
The processor is controlled to analyze the captured image in order to acquire the corneal shape data of the eye.
The processor is controlled to analyze the OCT data in order to acquire the fundus shape data of the eye.
The processor is controlled to create an eye model based on at least the corneal shape data and the fundus shape data.
Control the processor to perform a first evaluation of the effect of the orthokeratology lens on the eye based on at least the eye model.
How to control an ophthalmic device. A method of controlling an ophthalmic apparatus including an imaging unit that photographs the eye and a processor.
The imaging unit is controlled to acquire a captured image of the eye after the orthokeratology lens is removed.
The processor is controlled to receive OCT data acquired by applying optical coherence tomography to the fundus of the eye.
The processor is controlled to analyze the captured image in order to acquire the corneal shape data of the eye.
The processor is controlled to analyze the OCT data in order to acquire the fundus shape data of the eye.
The processor is controlled to create an eye model based on at least the corneal shape data and the fundus shape data.
Control the processor to perform a first evaluation of the effect of the orthokeratology lens on the eye based on at least the eye model.
How to control an ophthalmic device. A method of controlling an ophthalmic apparatus including an OCT unit and a processor that applies optical coherence tomography to the fundus.
The processor is controlled to receive the captured image obtained by photographing the eye after removing the orthokeratology lens.
The OCT unit is controlled to acquire OCT data of the fundus of the eye.
The processor is controlled to analyze the captured image in order to acquire the corneal shape data of the eye.
The processor is controlled to analyze the OCT data in order to acquire the fundus shape data of the eye.
The processor is controlled to create an eye model based on at least the corneal shape data and the fundus shape data.
Control the processor to perform a first evaluation of the effect of the orthokeratology lens on the eye based on at least the eye model.
How to control an ophthalmic device. A program that causes an ophthalmic apparatus including a computer to execute the control method according to any one of claims 16 to 18. An image analysis unit that analyzes the image of the eye after removing the orthokeratology lens and acquires corneal shape data.
An OCT data analysis unit that analyzes the OCT data acquired by applying optical coherence tomography to the fundus of the eye and acquires the fundus shape data.
An eyeball model creation unit that creates an eyeball model based on at least the corneal shape data and the fundus shape data,
An ophthalmic information processing apparatus including an evaluation unit that performs a first evaluation regarding the effect of the orthokeratology lens on the eye based on at least the eyeball model. A method of controlling an ophthalmic information processing device including a processor.
The processor is controlled to receive the captured image obtained by photographing the eye after removing the orthokeratology lens.
The processor is controlled to receive OCT data acquired by applying optical coherence tomography to the fundus of the eye.
The processor is controlled to analyze the captured image in order to acquire the corneal shape data of the eye.
The processor is controlled to analyze the OCT data in order to acquire the fundus shape data of the eye.
The processor is controlled to create an eye model based on at least the corneal shape data and the fundus shape data.
Control the processor to perform a first evaluation of the effect of the orthokeratology lens on the eye based on at least the eye model.
Control method of ophthalmic information processing device. A program that causes a computer to execute the control method of claim 21. A computer-readable non-temporary recording medium on which the program of claim 19 or 22 is recorded.

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