CN118302100A

CN118302100A - Deformation depth gauge for ophthalmic systems

Info

Publication number: CN118302100A
Application number: CN202280076558.0A
Authority: CN
Inventors: J·帕克; E·A·德霍格
Original assignee: Alcon Inc
Current assignee: Alcon Inc
Priority date: 2021-11-19
Filing date: 2022-11-15
Publication date: 2024-07-05

Abstract

In certain embodiments, an ophthalmic system includes a deformation depth gauge (ADG) device and a computer. The ADG apparatus measures the z-position of the interior of the eye and includes a detector array arrangement that is arranged at an oblique angle relative to the z-axis. The array generates a detector signal in response to detecting a light beam having a z-focus inside the eye. A set of line focus optics focuses the light beam to form a line focus on the detector array, and a set of nominal focus optics focuses the light beam to form a nominal focus on the detector array. The computer comprises: generating an image using the detector signal; determining the position of the nominal focus on the online focus according to the image; and determining the z-position of the z-focus based on the position of the nominal focus on the line focus.

Description

Deformation depth gauge for ophthalmic systems

Technical Field

The present disclosure relates generally to ophthalmic systems, and more particularly to a depth of deformation gauge for ophthalmic systems.

Background

Some ophthalmic surgical procedures involve targeting a laser beam at a target inside the eye. For example, laser vitrectomy treats an eye float by directing a laser beam toward the float to break the float. However, treatment of the eye with a laser requires clear imaging of the target and measuring the depth of the target within the eye. However, known solutions often do not provide adequate imaging or depth measurement.

Disclosure of Invention

In certain embodiments, an ophthalmic system includes a deformation depth gauge (ADG) device and a computer. The ADG apparatus measures a z-position of an interior of an eye having an eye axis defining a z-axis. The ADG apparatus includes a detector array, a set of line focus optics, and a set of nominal focus optics. The detector array is arranged at an oblique angle with respect to the z-axis. The array generates a detector signal in response to detecting a light beam having a z-focus inside the eye. The set of line focus optics focuses the light beam to form a line focus on the detector array, and the set of nominal focus optics focuses the light beam to form a nominal focus on the detector array. The computer comprises: generating an image using the detector signal; determining the position of the nominal focus on the online focus according to the image; and determining the z-position of the z-focus based on the position of the nominal focus on the line focus.

An embodiment may not include the following features or may include one, some or all of the following features:

* The bevel angle is in the range of 3 degrees to 60 degrees.

* The change in position of the nominal focus is proportional to the change in z position of the z focus.

* The image includes a rectangular shape representing a line focus, and the nominal focus corresponds to the narrowest portion of the rectangular shape. In an embodiment, the first z position of the z focus corresponds to the first position of the nominal focus and the second z position of the z focus corresponds to the second position of the nominal focus. The first z position of the z focus is different from the second z position of the z focus, and the first position of the nominal focus is different from the second position of the nominal focus. In an embodiment, the optimal z-focus corresponds to the narrowest portion centered on the rectangular shape.

* The set of line focus optical elements includes a cylindrical lens and a spherical lens, and the set of nominal focus optical elements includes a fan-out lens and a spherical lens.

* The set of line focus optical elements includes a toric lens and a focusing lens, and the set of line nominal focus optical elements includes a collimating lens and a focusing lens.

* The z focus is located on the target. The computer may determine the z-position of the target from the z-position of the z-focus. The ophthalmic system may further include a laser device that generates a laser beam, and the computer may instruct the laser device to direct the laser beam to the z position of the z focus point in order to direct the laser beam to the target. The ophthalmic system may further include an SLO device that determines an xy position of the target from the SLO image, wherein the z-axis defines an xy plane orthogonal to the z-axis.

* The computer determines whether the z focus is the best z focus based on the z position of the z focus. If the z focus is not the optimal z focus, the computer adjusts the z focus until the z focus is the optimal z focus. The computer may: determining whether the z-focus is the best z-focus by determining whether the image shows a rectangular shape and the narrowest portion is centered on the rectangular shape; and adjusting the z focus until the z focus is the best z focus by adjusting the z focus until the image shows a rectangular shape and the narrowest portion is centered on the rectangular shape.

* The z-axis defines an xy-plane orthogonal to the z-axis. The computer performs a number of iterations to produce an xy-plane image of the interior of the eye by: adjusting the z position of the z focus; and capturing an xy-plane image of the interior of the eye at the z-position of the z-focus. The computer combines the xy plane images to produce a three-dimensional image of the interior of the eye.

In certain embodiments, an ophthalmic surgical system includes a Scanning Laser Ophthalmoscope (SLO) -deformation depth gauge (ADG) system, a laser device, and a computer. The SLO-ADG system directs the imaging beam toward a target in the eye. The eye has an eye axis defining a z-axis, which in turn defines an xy-plane orthogonal to the z-axis. The SLO-ADG system determines an xyz position of the target and includes an SLO device and an ADG device. SLO apparatus: detecting an imaging beam reflected by the eye; generating an SLO image of a target in the eye; and determining the xy position of the target from the SLO image. ADG apparatus: detecting an imaging beam reflected by the eye; and determining the z-position of the target. The laser device directs the laser beam to an xyz position of the target, and the computer instructs the laser device to direct the laser beam to the xyz position of the target.

* The ADG apparatus includes a detector array, a set of line focus optics, and a set of nominal focus optics. The detector array is arranged at an oblique angle with respect to the z-axis. The detector array generates detector signals in response to detecting a light beam having a z-focus inside the eye. The set of line focus optics focuses the light beam to form a line focus on the detector array, and the set of nominal focus optics focuses the light beam to form a nominal focus on the detector array. The computer comprises: generating an image using the detector signal; determining the position of the nominal focus on the online focus according to the image; and determining the z-position of the z-focus based on the position of the nominal focus on the line focus. In some embodiments, the computer may determine the z-position of the target from the z-position of the z-focus. The change in position of the nominal focus may be proportional to the change in z position of the z focus. The image may be a rectangular shape representing a line focus, and the nominal focus may correspond to the narrowest portion of the rectangular shape.

* The ophthalmic surgical system includes an xy scanner that: receiving an imaging beam from the SLO-ADG system and directing the imaging beam along an imaging beam path toward an xy location of the target; and receives the laser beam from the laser device and directs the laser beam along a laser beam path aligned with the imaging beam path toward the xy position of the target.

In certain embodiments, a measurement system includes a deformation depth gauge (ADG) device and a computer. The ADG apparatus measures a z-position within a volume having a z-axis. The ADG apparatus includes a detector array, a set of line focus optics, and a set of nominal focus optics. The detector array is arranged at an oblique angle with respect to the z-axis. The detector array generates detector signals in response to detecting a light beam having a z-focus inside the volume. The set of line focus optics focuses the light beam to form a line focus on the detector array, and the set of nominal focus optics focuses the light beam to form a nominal focus on the detector array. The computer comprises: generating an image using the detector signal; determining the position of the nominal focus on the online focus according to the image; and determining the z-position of the z-focus based on the position of the nominal focus on the line focus.

* The z focus is located on the target. In an embodiment, the computer may determine the z-position of the target from the z-position of the z-focus. The ophthalmic system may further include an SLO device that determines an xy position of the target from the SLO image, wherein the z-axis defines an xy plane orthogonal to the z-axis. In an embodiment, the ophthalmic system may further comprise a laser device that generates a laser beam, and the computer may instruct the laser device to direct the laser beam to the z position of the z focus and/or the xy position of the target in order to direct the laser beam to the target.

Drawings

FIG. 1 illustrates an example of an ophthalmic laser surgical system for imaging and treating a target in an eye, in accordance with certain embodiments;

FIG. 2 illustrates an example of an SLO-ADG system that can be used in the system of FIG. 1 according to some embodiments;

FIG. 3 illustrates an example of an ADG device that may be used in the SLO-ADG system of FIG. 2, according to some embodiments;

FIG. 4 illustrates another example of an ADG device that may be used in the SLO-ADG system of FIG. 2, according to some embodiments;

FIG. 5 illustrates an example of how different positions of the z-focus produce different detector array patterns; and

Fig. 6 illustrates an example of a method for treating a target in an eye that may be performed by the system of fig. 1, in accordance with certain embodiments.

Detailed Description

Reference is now made in detail to the present exemplary embodiments of the disclosed apparatus, systems, and methods, examples of which are illustrated in the accompanying drawings. The description and drawings are not intended to be exhaustive or otherwise limit the claims to the precise embodiments shown in the drawings and disclosed in the specification. Although the drawings represent possible embodiments, the drawings are not necessarily to scale and certain features may be simplified, exaggerated, removed, or partially sectioned to better illustrate the embodiments.

Known laser surgical devices often do not provide adequate imaging or depth measurement of a target in the eye. Accordingly, the ophthalmic systems described herein include a deformation depth gauge (ADG) device that may be used to focus an imaging device on a target or to determine the depth of a target. The ADG apparatus receives a light beam focused at a point in the eye. The anamorphic optics arrangement of the ADG device modulates the light beam to produce a line focus with a nominal focus on the tilted linear detector array. The position of the nominal focus on the line focus indicates the depth of focus of the light beam in the eye. When the focus is optimal, the nominal focus is at a particular location of the line focus.

Embodiments of the ADG device have several applications in ophthalmic systems. For example, an ADG apparatus may be used to adjust the depth of focus of an imaging beam of an autofocus system. As another example, an ADG apparatus may be used to measure the position of a target relative to the focal point of an imaging beam. In this example, the laser device may utilize the target location to aim the laser beam. As yet another example, an ADG apparatus may be used to generate a three-dimensional (3D) image.

Embodiments of the ADG apparatus provide several advantages. For example, ADG can measure the depth (within hundreds of microns) of a target (such as an eye float) in a very short time. As another example, an ADG apparatus is less expensive than an Optical Coherence Tomography (OCT) depth gauge. As yet another example, ADG devices require relatively little signal processing.

Fig. 1 illustrates an example of an ophthalmic laser surgery system 10 for imaging and treating a target in an eye, in accordance with certain embodiments. In an example, the target may be a vitreous float. The eye has an eye axis (e.g., a visual axis or optical axis) that defines a z-axis. The z-axis defines an x-axis and a y-axis orthogonal to the z-axis, thereby defining an xy-plane. The x-axis, y-axis, and z-axis may (but need not) be positioned in accordance with the conventional coordinate system of the eye. The x-position, y-position, and z-position, and the x-direction, y-direction, and z-direction are associated with the x-axis, y-axis, and z-axis, respectively.

As an overview of the illustrated example, the system 10 includes an imaging system 20, a treatment system 22, a computer 23, an xy scanner 24, and optical elements 26 (26 a, 26 b) coupled as shown. The computer 23 includes logic, memory (which may store programs), and an interface (which may include a display).

As an overview of the operation, the imaging and measurement system 20 includes a Scanning Laser Ophthalmoscope (SLO) -deformation depth gauge (ADG) system that directs an imaging beam toward a target in the eye. The SLO-ADG system includes an SLO device and an ADG device. The SLO apparatus detects the imaging beam reflected by the eye, generates an SLO image of the target in the eye, and determines the xy position of the target from the SLO image. The ADG apparatus detects the imaging beam reflected by the eye and determines the z-position of the target. Treatment system 22 includes a laser device that directs a laser beam to the xyz position of the target. The xy scanner 24 receives the imaging beam from the imaging system 20 and directs the imaging beam along an imaging beam path toward the xy position of the target. The xy scanner 24 also receives a laser beam from a laser device and directs the laser beam along a laser beam path aligned with the imaging beam path toward the xy position of the target. The computer 23 sends instructions to the SLO-ADG system and the laser device.

Turning to the components, an example of the imaging system 20 is described in more detail with reference to FIG. 2. The laser device of treatment system 22 may include any suitable laser source that generates a laser beam having any suitable wavelength (e.g., 100 nanometers (nm) to 2000 nm). Examples of laser devices include femtosecond lasers or pulsed Nd: YAG laser. The dichroic mirror may couple the laser beam with the imaging beam.

The xy scanner 24 scans the treatment beam and the imaging beam laterally in the xy direction. Examples of scanners include galvanometer scanners (e.g., a pair of galvanometer-actuated scanner mirrors that can be tilted about mutually perpendicular axes), electro-optic scanners that can electro-optically manipulate a light beam (e.g., an electro-optic crystal scanner), or acousto-optic scanners that can acousto-optically manipulate a light beam (e.g., an acousto-optic crystal scanner). The xy scanner 36 may include an afocal relay system that allows compensation for refractive errors of the patient.

The optical element 26 directs the light beam to and/or from the eye. In general, the optical element may act upon (e.g., transmit, reflect, refract, diffract, collimate, adjust, shape, focus, modulate, and/or otherwise act upon) the laser beam. Examples of optical elements include lenses, prisms, mirrors, diffractive Optical Elements (DOEs), holographic Optical Elements (HOEs), and Spatial Light Modulators (SLMs). Lens 26b may be moved to compensate for the refractive error.

Computer 23 controls the components of system 10 such as imaging system 20, treatment system 22, computer 23, xy scanner 24, and optical element 26. The computer 23 may be part of the component or separate from the component. For example, the computer 23 may be part of an SLO-ADG system to perform the operations of the system.

Fig. 2 illustrates an example of an SLO-ADG system 30 that may be used in the system 10 of fig. 1, in accordance with certain embodiments. In an example, the SLO-ADG system 30 includes a light source 32, a pinhole and detector 34, a depth gauge 36, a beam splitter 38 (38 a, 38 b), an xy scanner 24, and optical elements 26 (26 c ) coupled as shown. The SLO apparatus of SLO-ADG system 30 may include light source 32, optical elements 26c, 26d, beam splitter 38a, and pinhole and detector 34. The ADG apparatus of the SLO-ADG system 30 may include a light source 32, a beam splitter 38b, and a depth gauge 36. In some embodiments, the SLO device and the ADG device may share the light source 32.

As an example of operation, the light source 32 directs light through the lens 26c toward the xy scanner 24. The xy scanner 24 directs light toward the eye and directs light reflected from the eye toward the beam splitter 38. The beam splitters 38a, 38b direct reflected light to the pinhole and detector 34 and the depth gauge 36, respectively. The pinhole and detector 34 detects the light and generates an SLO image from the light. The depth gauge 36 measures the z-position of the feature and/or the target.

And a steering unit, wherein the SLO device generates an SLO image of the interior of the eye. In general, SLO devices can provide higher field of view (FOV) imaging, which can facilitate detection of targets such as floats or other vitreous opacities during treatment. For example, the SLO image enhances the contrast between the float (or float shadow) and the retina, allowing for easier detection of the float. The SLO apparatus can detect an object in an image using image processing.

In some embodiments, the ADG apparatus 50 provides real-time depth information of the target. If the float is too close to the retina, the system 10 may alert the user that there may be laser induced retinal damage. The ADG apparatus 50 is described in more detail with reference to fig. 3 to 5. In an embodiment, the computer 23 may output the image via a display.

Fig. 3-5 depict examples of ADG devices 50 (50 a, 50 b) that may be used in the system 10 of fig. 1 according to certain embodiments. Fig. 3 shows an example of an ADG apparatus 50a that includes afocal optics 52, cylindrical lenses 54, fan-out lenses 56, spherical lenses 58, and a linear detector array 60. In the illustrated example, the line focus optical elements include cylindrical lenses 54 and spherical lenses 58, and the nominal focus optical elements include fan-out lenses 56 and spherical lenses 58.

The detector array 60 is tilted about the x-axis and at an oblique angle relative to the z-axis. The bevel angle may have any suitable value, for example, a value in the range of 3 degrees to 60 degrees (such as in the range of 3 degrees to 10 degrees, 10 degrees to 20 degrees, 20 degrees to 30 degrees, 30 degrees to 40 degrees, 40 degrees to 50 degrees, and/or 50 degrees to 60 degrees). The detector array 60 may have any suitable size, for example, a width of 0.1 centimeters (cm) to 2cm (such as 0.1cm to 0.5cm, 0.5cm to 1cm, 1cm to 1.5cm, and/or 1.5cm to 2 cm) and a length of 0.5cm to 10cm (such as 0.5cm to 1cm, 1cm to 2cm, 2cm to 3cm, 3cm to 5cm, 5cm to 7cm, and/or 7cm to 10 cm).

Afocal optic 52 receives a light beam reflected from the interior of the eye such that the focal point of the light beam is located within the eye. In the yz plane, cylindrical lens 54 and spherical lens 58 form a kepler telescope, where cylindrical lens 54 focuses the beam and spherical lens 58 collimates the beam, producing a line focus at linear detector array 60. In the xz plane, a fan-out lens 56 and a spherical lens 58 focus the beam onto a linear detector array 60.

Fig. 4 shows an example of an ADG apparatus 50b that includes a collimating lens 60, a toric lens 62, a focusing lens 64, and a linear detector array 68 with pixels 71 arranged in a linear fashion. In the example, the line focus optical element includes a toric lens 62 and a focusing lens 64, and the nominal focus optical element includes a collimating lens 60 and a focusing lens 64.

In an example, the linear detector array 68 is tilted about the x-axis and at an oblique angle relative to the z-axis. The bevel angle may have any suitable value, for example, an angle within the range as described above with respect to the detector array 60. In the yz plane, toric lens 62 fans out the beam along the y-axis and focusing lens 64 collimates the beam in the y-axis while focusing the beam along the x-axis, producing a line focus 74 on detector array 68. In the xz plane, collimating lens 60 and focusing lens 64 focus the beam onto linear detector array 68 to produce a nominal y-focus 72 on detector array 68. The nominal y-focus 72 is a nominal position along the y-axis of the detector that corresponds to the nominal focus position. The optimal z focus 70 produces a nominal y focus 72 centered relative to a line focus 74. The best z-focus 70 indicates the location of the focus of the object (i.e., with the sharpest image).

Fig. 5 illustrates an example of how different positions of the z-focus 70 may produce different patterns on the detector array 68 that indicate different positions of the nominal y-focus 72. In an example, the linear detector array 68 detects a rectangular shape representing a line focus, and the nominal y focus 72 is the narrowest portion of the shape. The pattern shows that the nominal y-focus 72 moves along the y-axis according to the defocus or change of the z-focus 70. For example, in the case of the optimal z focus 70, the nominal y focus 72 is centered with respect to the line focus 74. The nominal y focus 72 moves in one direction at a distance of-2 millimeters (mm) from the optimal z focus 70, and the nominal y focus 72 moves in the other direction at a distance of +2mm from the optimal z focus 70.

The relationship describing the nominal y focus resulting from a particular z focus may depend on the particular arrangement of components. The relationship may be determined (e.g., during collimation) by: shift the z focus, record the resulting nominal y focus, and determine the relationship between the z focus and the resulting nominal y focus, for example, using regression analysis.

As shown in the example, as the input z-focus 70 moves in the z-direction (FIG. 4), the nominal y-focus 72 moves over the linear detector array 68 such that different z-positions of the z-focus 70 correspond to different positions of the nominal y-focus 72. The amount of movement of nominal y-focus 72 is proportional to the amount of movement of z-focus 70, i.e., the change in position of nominal y-focus 72 is proportional to the change in z-position of z-focus 70. Accordingly, given the position of nominal y-focus 72, the z-position of z-focus 70 may be determined, as indicated by the pattern detected by detector array 68.

The embodiment of the ADG apparatus 50 has several applications in ophthalmic systems. For example, an ADG device may be used to measure the z-position of a target, and a laser device may use the z-position to aim a laser beam at the target. This will be described in more detail with reference to fig. 6.

As another example, an ADG apparatus may be used to adjust the depth of focus of an autofocus system. In some embodiments, the computer determines whether the z focus is optimal. For example, the computer may determine whether the image shows a rectangular shape with the narrowest portion centered in the middle of the shape. If the z focus is not optimal, the computer adjusts the z focus until the z focus is optimal. For example, the computer may adjust the z-focus until the image shows a rectangular shape with the narrowest portion centered in the shape.

As another example, an ADG apparatus may be used to generate a three-dimensional (3D) image. In some embodiments, the z focus may be adjusted to different z positions to capture xy plane images at different z positions. The xy plane images may be combined to generate a 3D image, such as a 3D image of a float.

Fig. 6 illustrates an example of a method for imaging and treating a target in an eye (e.g., an eye float) that may be performed by the system 10 of fig. 1, in accordance with certain embodiments. The method begins at step 110 where the SLO-ADG apparatus directs an imaging beam toward a target in the eye. At step 112, the slo apparatus detects the imaging beam reflected by the eye. In step 114, the SLO apparatus generates an SLO image of the target, and in step 116, the apparatus determines the xy position of the target from the SLO image. For example, the SLO apparatus can determine the xy position of the target from the image using image processing.

The adg apparatus detects the imaging beam reflected by the eye at step 118 and determines the z-position of the target at step 120. For example, the ADG apparatus generates an image indicative of the nominal focus position from the imaging beam and then determines the z-position of the z-focus from the nominal focus position. If the target is at the z-focus, then the z-position of the target is the same as the z-position of the z-focus. In step 122, the laser device directs the laser beam to the xy and z positions of the target.

Components of the systems and apparatus disclosed herein, such as a control computer, may include interfaces, logic, and/or memory, any of which may include computer hardware and/or software. Interfaces may receive input to and/or transmit output from components and are typically used to exchange information between, for example, software, hardware, peripheral devices, users, and combinations of these. A user interface is one type of interface that a user may use to communicate with a computer (e.g., send input to and/or receive output from a computer). Examples of user interfaces include displays, graphical User Interfaces (GUIs), touch screens, keyboards, mice, gesture sensors, microphones, and speakers.

Logic may perform operations of the components. Logic may include one or more electronic devices that process data (e.g., execute instructions for generating output from input). Examples of such electronic devices include computers, processors, microprocessors (e.g., central Processing Units (CPUs)) and computer chips. Logic may comprise computer software encoding instructions capable of being executed by an electronic device to perform operations. Examples of computer software include computer programs, application programs, and operating systems.

The memory may store information and may include tangible, computer-readable, and/or computer-executable storage media. Examples of memory include computer memory (e.g., random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (e.g., a hard disk), removable storage media (e.g., a Compact Disk (CD) or digital video or versatile disk (DVD)), databases, network storage (e.g., a server), and/or other computer-readable media. Particular embodiments may relate to memory encoded with computer software.

While the present disclosure has been described in terms of certain embodiments, modifications to these embodiments (such as alterations, substitutions, additions, omissions, and/or other modifications) will be apparent to those skilled in the art. Accordingly, modifications may be made to the embodiments without departing from the scope of the invention. For example, modifications may be made to the systems and apparatus disclosed herein. The components of the systems and apparatus may be integrated or separated, or the operations of the systems and apparatus may be performed by more, fewer, or other components, as will be apparent to those of skill in the art. As another example, modifications may be made to the methods disclosed herein. These methods may include more, fewer, or other steps, and the steps may be performed in any suitable order, as will be apparent to those of skill in the art.

To assist the patent office and reader in understanding the claims, the applicant does not intend for any claim or claim element to refer to 35u.s.c. ≡112 (f) unless the word "means for … …" or "steps for … …" is explicitly used in a particular claim. Applicant understands that the use of any other term (e.g., "mechanism," "module," "apparatus," "unit," "component," "element," "means," "machine," "system," "processor," or "controller") within the claims refers to a structure known to those skilled in the relevant art and is not intended to refer to 35u.s.c. ≡112 (f).

Claims

1. An ophthalmic system comprising:

A deformation depth gauge ADG device configured to measure a z-position of an interior of an eye having an eye axis defining a z-axis, the ADG device comprising:

A detector array disposed at an oblique angle relative to the z-axis, the detector array configured to generate detector signals in response to detecting a light beam having a z-focus inside the eye;

A set of line focus optics configured to focus the light beam to form a line focus on the detector array; and

A set of nominal focus optics configured to focus the light beam to form a nominal focus on the detector array; and

A computer configured to:

Generating an image using the detector signal;

Determining a position of the nominal focus on the line focus from the image; and

And determining the z position of the z focus according to the position of the nominal focus on the line focus.

2. The ophthalmic system of claim 1, the oblique angle being in the range of 3 degrees to 60 degrees.

3. The ophthalmic system of claim 1, the change in position of the nominal focus being proportional to the change in z position of the z focus.

4. The ophthalmic system of claim 1:

the image comprising a rectangular shape representing the line focus; and

The nominal focus corresponds to the narrowest portion of the rectangular shape.

5. The ophthalmic system of claim 4:

a first z position of the z focus corresponds to a first position of the nominal focus; and

The second z position of the z focus corresponds to the second position of the nominal focus, the first z position of the z focus is different from the second z position of the z focus, and the first position of the nominal focus is different from the second position of the nominal focus.

6. The ophthalmic system of claim 4, the optimal z-focus corresponding to a narrowest portion centered on the rectangular shape.

7. The ophthalmic system of claim 1:

The set of line focus optical elements includes a cylindrical lens and a spherical lens; and

The set of nominal focus optical elements includes a fan-out lens and the spherical lens.

8. The ophthalmic system of claim 1:

the set of line focus optical elements includes a toric lens and a focusing lens; and

The set of line nominal focus optical elements includes a collimating lens and the focusing lens.

9. The ophthalmic system of claim 1, the z-focus being located on a target.

10. The ophthalmic system of claim 8, the computer configured to determine a z-position of the target from a z-position of the z-focus.

11. The ophthalmic system of claim 8:

The ophthalmic system further includes a laser device configured to generate a laser beam; and

The computer is configured to instruct the laser device to direct the laser beam to a z position of the z focus in order to direct the laser beam to the target.

12. The ophthalmic system of claim 8, the z-axis defining an xy-plane orthogonal to the z-axis, the ophthalmic system further comprising an SLO device configured to determine an xy-position of the target from the SLO image.

13. The ophthalmic system of claim 1, the computer configured to:

determining whether the z focus is an optimal z focus according to the z position of the z focus; and

And if the z focus is not the optimal z focus, adjusting the z focus until the z focus is the optimal z focus.

14. The ophthalmic system of claim 13, the computer configured to:

Determining whether the z-focus is the best z-focus by determining whether the image shows a rectangular shape and a narrowest portion is centered on the rectangular shape; and

The z focus is adjusted until the z focus is the best z focus by adjusting the z focus until the image shows the rectangular shape and the narrowest portion is centered on the rectangular shape.

15. The ophthalmic system of claim 1, the z-axis defining an xy-plane orthogonal to the z-axis, the computer configured to:

performing a plurality of iterations to produce a plurality of xy-plane images of the interior of the eye:

adjusting the z position of the z focus;

capturing an xy-plane image of the interior of the eye at a z-position of the z-focus; and

The plurality of xy plane images are combined to produce a three-dimensional image of the interior of the eye.

16. An ophthalmic surgical system comprising:

A scanning laser ophthalmoscope SLO-deformation depth gauge ADG system configured to direct an imaging beam towards a target in an eye, the eye having an eye axis defining a z-axis defining an xy-plane orthogonal to the z-axis, the SLO-ADG system configured to determine the xyz-position of the target, the SLO-ADG system comprising:

SLO apparatus configured to:

Detecting an imaging beam reflected by the eye;

generating an SLO image of a target in the eye; and

Determining the xy position of the target according to the SLO image;

an ADG apparatus configured to:

Detecting an imaging beam reflected by the eye; and

Determining a z-position of the target;

A laser device configured to direct a laser beam to an xyz position of the target; and

A computer configured to instruct the laser device to direct the laser beam to an xyz position of the target.

17. The ophthalmic surgical system of claim 16:

The ADG apparatus includes:

The computer is configured to:

Generating an image using the detector signal;

18. The ophthalmic system of claim 17, the computer configured to determine a z-position of the target from a z-position of the z-focus.

19. The ophthalmic system of claim 17, the change in position of the nominal focus being proportional to the change in z position of the z focus.

20. The ophthalmic system of claim 17:

the image comprising a rectangular shape representing the line focus; and

21. The ophthalmic surgical system of claim 16, further comprising an xy scanner configured to:

receiving an imaging beam from the SLO-ADG system and directing the imaging beam along an imaging beam path toward an xy position of the target; and

The laser beam from the laser device is received and directed along a laser beam path aligned with the imaging beam path toward an xy position of the target.