CN112857263A - Oblique illumination type color confocal measurement system and detection method - Google Patents
Oblique illumination type color confocal measurement system and detection method Download PDFInfo
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Abstract
The invention relates to an oblique illumination type color confocal measuring system and a detection method. The light source module emits a polychromatic light beam, the polychromatic light beam is dispersed into a plurality of light beams with different wavelengths through the dispersion lens module and then focused on a measured object on the moving object carrying module, the moving object carrying module is moved to collect image information of each position on the surface of the measured object, the optical fiber is reflected to the reflection lens module again and reflected by 180 degrees, and the reflected light beam is emitted to the collection and calculation module. The acquisition and calculation module acquires the wavelength and color information of the focusing light spot reflected by the surface of the measured object, calculates the relative axial height data of the surface of the measured object according to the wavelength information, and carries out three-dimensional point cloud modeling on the axial height of the sampling point information and the corresponding horizontal position coordinate information to generate a surface morphology image. The measuring system and the detecting method are suitable for detecting the surface topography of the sample when the geometric space is limited.
Description
Technical Field
The invention relates to the field of non-contact surface three-dimensional topography detection, in particular to an oblique illumination type color confocal measurement system and a detection method.
Background
With the rapid development of scientific technology, the industry upgrading of the manufacturing industry is driven to make the produced and processed products more and more precise, and the society also puts higher requirements on the surface three-dimensional shape detection technology of high-precision products. Surface measurement technology spans many different fields such as science and industry, and is widely applied in the fields of biomedicine, geological samples, processing materials, mechanical parts, integrated circuits, micro-electromechanical systems, optical elements and the like. At present, in the field of surface three-dimensional morphology detection, an optical detection method has become a mainstream surface detection mode over the traditional contact measurement due to the advantages of non-contact, high precision, high speed, strong adaptability and the like. The method for acquiring the three-dimensional morphology usually needs to utilize an optical sensor to scan different point information on the surface of a measured object by combining a three-dimensional moving platform to realize high-precision microscopic morphology restoration. The optical detection method generally comprises a white light interference method, a laser triangulation method, an astigmatism method, a laser confocal method and the like, and the detection method needs axial scanning, so that the detection method cannot adapt to the high efficiency requirement of modern production and life due to long time. In order to reduce the time of mechanical scanning and improve the environmental adaptability of the sensor, a color confocal technology based on the spectral coding principle is proposed.
The color confocal technology principle is that the surface of a measured object is scanned by combining a mechanical displacement device, the wavelength information change acquired by a sensor reflects displacement information, compared with the traditional laser confocal measuring method, the detection time is saved without axial scanning, the detection speed is improved, and the color confocal technology can realize submicron-level detection precision.
The conventional color confocal measurement system usually measures perpendicular to a measured object, but there are special cases in real production life that limit the measurement scheme in the perpendicular direction, for example, when the system is applied to the detection of the surface topography of an aircraft engine rotor blade, the geometric space measured in the perpendicular direction is compressed due to the very narrow space between two blades, and such a case also often occurs in other industrial detection fields.
Disclosure of Invention
The invention aims to solve the technical problem that the existing color confocal measurement system is perpendicular to a measured object to carry out measurement and is applied to the situation that the space is limited when a specific scene such as a narrow space is adopted.
In order to solve the technical problems, the invention provides a color confocal measurement system for collecting surface information of an object in an oblique illumination mode, which can realize measurement at different geometric angles, and the scheme can be applied and popularized to other related surface topography measurement fields. The technical scheme of the invention is as follows.
An oblique illumination type color confocal measurement system comprises a light source module, a dispersion lens module, a moving object carrying module, a reflection lens module and a collecting and calculating module. The light source module faces the dispersion lens module; the dispersion lens module is provided with a linear incident light channel, and the reflection lens module is provided with a linear reflected light channel; the central extension lines of the incident light channel and the reflected light channel are intersected on the surface of the object to be measured loaded on the moving object carrying module; the incident light is obliquely emitted to the surface of the measured object loaded on the moving object carrying module; the included angle between the central line of the incident light and the normal line of the object carrying surface is an incident angle, and the incident angle is larger than the signal collecting angle of the dispersion lens module. In order to prevent the acquisition and calculation module from being interfered by the light directly reflected by the surface of the object to be measured, it is necessary to ensure that the measurement is performed under the condition that the measurement inclination angle (i.e., the incident angle) is larger than the signal collection angle of the dispersion lens module. The tail end of the reflecting lens module is a pyramid prism; and a light collection channel is arranged on the side of the dispersion lens module and faces the collection calculation module. The acquisition and calculation module is also connected to the moving carrier module.
The scheme of the invention utilizes the color confocal distance measuring method to collect the surface information of the measured object in an inclined mode, and the measured light cannot be directly reflected back to the sensor by the surface of the sample due to the fact that the measured light deflects to other directions, so that the reflected lens module is added to totally reflect the focused light back to the receiving system to collect the light beam information. The system generates a surface three-dimensional topography map by combining a height change value of the whole surface of a measured object which is scanned and measured by a moving object carrying module.
As a further improvement of the oblique illumination type color confocal measuring system, the central line of the incident light channel and the central line of the reflected light channel are perpendicular to each other.
As a further improvement of the oblique illumination type color confocal measurement system, the light source module comprises a light source, an incident optical fiber and a first small hole mechanism; the first small hole mechanism is provided with a first small hole; one end of the incident optical fiber is connected to the light source, and the other end of the incident optical fiber faces the first small hole and the dispersive lens module at the rear end of the first small hole.
As a further improvement of the oblique illumination type chromatic confocal measurement system, the dispersive lens module comprises a first dispersive tube lens, a second dispersive tube lens, a spectroscope and a first objective lens; the first dispersion tube lens, the spectroscope and the first objective lens are sequentially arranged on an incident light path from front to back; the second spectroscope is arranged on the side of the spectroscope to form the light collecting channel, and the light collecting channel is vertical to the incident light path; the incident angle of the incident light is larger than the signal collection angle of the first objective lens.
As a further improvement of the oblique illumination type color confocal measurement system, the reflection lens module comprises a second objective lens, a collimating lens and a pyramid prism which are arranged on a reflection light path; the second objective lens, the collimating lens and the pyramid prism are arranged from near to far relative to the moving object carrying module.
As a further improvement of the oblique illumination type color confocal measuring system, the moving object carrying module comprises an X-Y displacement platform; the X-Y displacement platform is provided with three overlapped moving layers, the bottom layer is fixed, the middle layer moves longitudinally relative to the bottom layer, the upper layer moves transversely relative to the middle layer, and the upper layer is used for loading a measured object.
As a further improvement of the oblique illumination type color confocal measurement system, the acquisition and calculation module comprises a second small hole mechanism, an optical sensor and a computer; the second small hole mechanism is provided with a second small hole; the light of the light collection channel reaches the optical sensor through the second small hole, the optical sensor is connected to the computer, and the computer is further connected to the moving object carrying module.
The invention also provides an oblique illumination type color confocal detection method, which is applied to the oblique illumination type color confocal measurement system and comprises the following steps:
p1, the light source module emits a polychromatic light beam, the polychromatic light beam passes through the dispersion lens module, is dispersed into a plurality of light beams with different wavelengths, is focused on the surface of the measured object loaded on the moving object carrying module, and moves the moving object carrying module to acquire image information of each position on the surface of the measured object;
p2, incident light is reflected to the reflection lens module on the surface of the object to be measured, reflected by 180 degrees of the pyramid prism at the end of the reflection lens module, and returns to the moving carrier module;
p3, the light beam passing through the step P2 is reflected back to the incident light channel of the dispersion lens module, reflected to the light collection channel at the side of the dispersion lens module in the incident light channel, and finally emitted to the collection and calculation module; the acquisition and calculation module acquires the wavelength and color information of a focusing light spot reflected by the surface of the measured object, calculates the relative axial height data of the surface of the measured object by combining the wavelength information and the displacement information of the moving carrying module, and carries out three-dimensional point cloud modeling on the axial height of the sampling point information and the corresponding horizontal position coordinate information to generate a surface morphology image.
As a further improvement of the oblique illumination type confocal color inspection method of the present invention, step P1 specifically includes:
the light source emits polychromatic light, the polychromatic light is transmitted to the first small hole through the incident optical fiber to generate a point light source, after passing through the first dispersion tube lens, the spectroscope and the first objective lens, the polychromatic light of the point light source is dispersed into light beams with different wavelengths, the light beams with different wavelengths are respectively focused on different optical path axial height positions of a measured object, and the focuses of all the wavelengths are sequentially arranged at the axial positions according to wavelength changes; and scanning and sampling each position point on the surface of the measured object by controlling the moving track of the moving object carrying module.
As a further improvement of the oblique illumination type confocal color inspection method of the present invention, step P2 specifically includes:
incident light is reflected to the reflection lens module on the surface of a measured object, the reflected light sequentially passes through the second objective and the collimating lens, the collimating lens gathers the diffused light beams into collimated light beams and transmits the collimated light beams to the pyramid prism, and the pyramid prism reflects the light beams back to the moving object carrying module in a 180-degree original circuit.
The oblique illumination type color confocal measurement system projects test light to the surface of a measured object at an oblique angle, light spots with different wavelengths are focused to different axial heights, the light spots are reflected to the other direction and then are totally reflected back to the measurement system through the reflection lens module, when the axial position of the measured object is changed, the light wavelength collected by the optical sensor is changed, the relative height change of the measured point is obtained by collecting the wavelength change of different sampling points, and the collection and calculation module carries out point cloud modeling on all the sampling points of the measured object to generate surface three-dimensional morphology information. The measuring system and the detecting method are suitable for narrow space application scenes such as detection of the surface appearance of the rotor blade of the aircraft engine.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1 is an overall structure diagram of an oblique illumination type color confocal measurement system according to the present invention;
FIG. 2 is a schematic diagram of a polychromatic light beam emitted by the light source in FIG. 1, which is dispersed into a plurality of light beams with different wavelengths after passing through a first dispersing tube mirror, and the focal points of the light beams with different wavelengths are sequentially arranged at axial positions according to wavelength changes;
fig. 3 is a schematic structural view of the X-Y displacement stage of fig. 1.
FIG. 4 is a schematic flow chart of the oblique illumination type confocal color inspection method of the present invention;
the labels in the figure are: the device comprises a light source 1, an incident optical fiber 2, a first small hole mechanism 3-1, a second small hole mechanism 3-2, a first dispersion tube lens 4-1, a second dispersion tube lens 4-2, a first objective lens 5-1, a second objective lens 5-2, a measured object 6, an X-Y displacement platform 7, a collimating lens 8, a pyramid prism 9, a spectroscope 10, an optical sensor 11 and a computer 12.
Detailed Description
The invention discloses an oblique illumination type color confocal measurement system and a detection method, and aims to provide a novel method for measuring the three-dimensional topography of the surface of an object in an oblique manner under the condition that the conventional vertical measurement manner is limited in space. The structure and operation steps of the technical solution of the present invention are described in detail below with reference to the accompanying drawings so as to facilitate the understanding and understanding of the objects, structures and functions of the present invention, but not to limit the scope of the present invention as set forth in the appended claims.
The invention relates to an oblique illumination type color confocal measurement system which comprises a light source module, a dispersion lens module, a moving object carrying module, a reflection lens module and an acquisition and calculation module. The light source module faces the dispersion lens module; the dispersion lens module is provided with a linear incident light channel, and the reflection lens module is provided with a linear reflected light channel; the central extension lines of the incident light channel and the reflected light channel are intersected on the surface of the object to be measured loaded on the moving object carrying module; the incident light is obliquely emitted to the surface of the measured object loaded on the moving object carrying module; the included angle between the central line of the incident light and the normal line of the object carrying surface is an incident angle, and the incident angle is larger than the signal collecting angle of the dispersion lens module. In order to prevent the acquisition and calculation module from being interfered by the light directly reflected by the surface of the object to be measured, it is necessary to ensure that the measurement is performed under the condition that the measurement inclination angle (i.e., the incident angle) is larger than the signal collection angle of the dispersion lens module. The tail end of the reflecting lens module is a pyramid prism; and a light collection channel is arranged on the side of the dispersion lens module and faces the collection calculation module. The acquisition and calculation module is also connected to the moving carrier module.
The scheme of the invention utilizes a color confocal distance measuring method to acquire the surface information of the measured object in an inclined mode, and the inclined angle can be 30 degrees, 45 degrees, 60 degrees, 75 degrees and the like. The measuring light is deflected to other directions by the inclination angle and cannot be directly reflected back to the sensor by the surface of the sample, so that the reflecting lens module is added to totally reflect the focusing light back to the receiving system for collecting the light beam information. The system generates a surface three-dimensional topography map by combining a height change value of the whole surface of a measured object which is scanned and measured by a moving object carrying module.
The central line of the incident light channel and the central line of the reflected light channel are perpendicular to each other.
As shown in fig. 1, the light source module includes a light source 1, an incident optical fiber 2, and a first aperture mechanism 3-1. The first small hole mechanism 3-1 is provided with a first small hole; one end of the incident optical fiber is connected to the light source 1, and the other end faces the first small hole and the dispersive lens module at the rear end of the first small hole. Wherein, the light source 1 is HL-2000-fhsa halogen tungsten lamp light source of ocean optics company, the polychromatic light beam emitted by the light source 1 is white light with continuous spectrum information, and the spectrum wavelength comprises from 400nm to 800 nm. The incident optical fiber 2 is made of a silica material and includes a core, a cladding and a coating layer. The light source 1 transmits polychromatic light to the first aperture through the incident optical fiber 2 to generate a point light source.
As shown in fig. 1, the dispersive lens module includes a first dispersive tube lens 4-1, a second dispersive tube lens 4-2, a beam splitter 10 and a first objective lens 5-1. The first dispersion tube lens 4-1, the spectroscope 10 and the first objective lens 5-1 are sequentially arranged on an incident light path from front to back. The first small hole mechanism 3-1 is connected with the first dispersion tube lens 4-1, and the relative position is controlled by a knob. The second dispersion tube lens 4-2 is arranged at the side of the spectroscope 10 to form the light collection channel, and the light collection channel is perpendicular to the incident light path. The incident angle of the incident light is larger than the signal collection angle of the first objective lens 5-1. The incident light of the measuring system measures the surface of the measured object in an inclination angle mode, and in order to prevent the acquisition and calculation module from being interfered by the light directly reflected by the surface of the measured object, the measurement is carried out under the condition that the measurement inclination angle is larger than the signal collection angle of the first objective lens 5-1.
As shown in fig. 2, the polychromatic light emitted from the light source 1 becomes a point light source after passing through the first small hole, and is dispersed into light beams of different wavelengths after passing through the dispersion lens module, and the focal points of the wavelengths are sequentially arranged at axial positions according to the wavelength change. Specifically, when the point light source enters the first dispersion tube lens 4-1, the light with different wavelengths is different in refraction angle due to different wavelengths in the same medium glass, axial chromatic aberration is formed after refraction, and the light with different wavelengths is focused to different axial heights along the z direction through the first objective lens 5-1 to generate a group of focused light spots with continuously changing wavelengths.
As shown in fig. 1, the reflective lens module includes a second objective lens 5-2, a collimating lens 8 and a corner cube 9 disposed on the reflected light path; the second objective lens 5-2, the collimating lens 8 and the pyramid prism 9 are arranged from near to far relative to the moving carrier module. The second objective lens 5-2 and the collimator lens 8 function to focus the diffused light beam into a collimated light beam to be transmitted to the corner cube 9. The corner cube 9 is a reflector, and is an internal total reflector composed of plane mirrors with three perpendicular sides, and when light is projected to the corner cube 9, the light is reflected back to the original light path at 180 degrees.
The spectroscope 10 is a semitransparent half-reflecting mirror, the illumination light emitted by the system can pass through the spectroscope 10, and the spectroscope 10 can deflect the light reflected by the pyramid prism 9 to the second dispersion tube lens 4-2.
As shown in fig. 1, the moving carrier module comprises an X-Y displacement platform 7. As shown in fig. 3, the X-Y displacement platform 7 has three overlapped moving layers, the bottom layer is fixed, the middle layer moves longitudinally relative to the bottom layer, the upper layer moves transversely relative to the middle layer, and the upper layer is used for loading the object to be measured 6. The X-Y displacement platform 7 consists of two motors, a spiral guide rail and three layers of metal flat plates, and the motors are controlled by a computer to send instructions to control the rotation of the motors, so that the moving track of the metal flat plates on an X-axis and a Y-axis is controlled, and the scanning sampling of each position point of the whole surface of the sample to be detected can be realized. In fig. 1, two focus points on the object to be measured 6 represent light spots respectively formed on the surfaces of the high step and the low step of the object to be measured 6 after the X-Y displacement platform 7 is moved left and right in the two testing processes, and the two light spots are on the same focus axis.
As shown in fig. 1, the acquisition and calculation module comprises a second aperture mechanism 3-2, an optical sensor 11 and a computer 12; the second small hole mechanism 3-2 is provided with a second small hole; the light of the light collection channel reaches the optical sensor 11 through the second small hole, the optical sensor 11 is connected to the computer 12, and the computer 12 is further connected to the moving object carrying module and used for controlling the movement of the X-Y displacement platform 7.
Referring to fig. 1, the oblique illumination type color confocal measurement system is utilized to perform oblique illumination type color confocal measurement to detect the three-dimensional surface topography of a sample, and the detection method includes the following steps:
p1, the light source 1 emits polychromatic light, the polychromatic light is transmitted through a first small hole arranged in a first small hole mechanism 3-1 through an incident optical fiber 2 to generate a point light source, the divergent polychromatic light of the point light source becomes parallel light after passing through the first dispersion tube lens 4-1, the parallel light is dispersed into light beams with different wavelengths after passing through the spectroscope 10 and then passing through the first objective lens 5-1, the parallel polychromatic light is focused on different optical path axial height positions of the object to be measured, and the focuses of each wavelength are sequentially arranged at the axial positions according to wavelength variation; the measuring light (light beams with different wavelengths) is projected to the surface of the measured object 6 at an inclined angle, the measured object 6 is fixed on the X-Y displacement platform 7, and the moving track of the X-Y displacement platform 7 is controlled by the computer 12 to realize scanning sampling of each position point on the surface of the measured object 6;
p2, the focus spot is reflected to the other end direction perpendicular to the normal line through the surface of the measured object 6 in an inclined way, and is reflected out in the inclined angle direction of the plane of the measured object 6, the reflected light sequentially passes through the second objective 5-2 and the collimating lens 8, the collimating lens 8 is used for converging the diffused light beam into a collimated light beam and transmitting the collimated light beam to the pyramid prism 9, the distance between the collimating lens 8 and the measured object 6 is adjusted to the optimal collimating position in the detection process, the generated collimated light beam is parallel to the central axis of the reflecting end, the collimated light beam reaches the pyramid prism 9, and the pyramid prism 9 reflects the light beam back to the X-Y displacement platform 7 in a 180-degree original path;
p3, the light beam from step P2 is reflected back to the incident light channel of the dispersion lens module, and passes through the first objective lens 5-1 to become a parallel light beam, and then is reflected to the lateral light collection channel by the beam splitter 10, namely, the reflected light beam passes through the second dispersion tube lens 4-2 and is emitted to the optical sensor 11 through a second small hole arranged on the second small hole mechanism 3-2, the optical sensor 11 converts the reflected light beam information into an electric signal and transmits the electric signal to the computer 12, the sampling time interval and the sampling times are set through an acquisition program in the computer 12, the computer 12 acquires the wavelength and the color information of a focusing light spot reflected by the surface of the measured object, the relative axial height data of the surface of the measured object is calculated through the wavelength information and the displacement information of the moving carrying module, and the axial height of the sampling point information and the corresponding horizontal position coordinate information are subjected to three-dimensional point cloud modeling to generate a surface morphology image.
As shown in fig. 4, the oblique illumination type confocal color detection method is further summarized as follows:
s1: projecting an illumination light path of the color confocal measurement system to the surface of a measured object at an inclined angle, adjusting a collimating lens and a pyramid prism to the optimal collimating position, and reflecting light back to a collecting end;
s2: placing a sample to be detected on an X-Y displacement table 7, setting the sampling frequency, the scanning path and the scanning speed of the displacement table 7 in the upper computer control software of the computer 12, and scanning the sample;
s3: carrying out standard correction on the color confocal measurement system;
s4: the computer software controls the trigger motor displacement platform to move and the image acquisition device, the displacement platform 7 starts to acquire the surface of the measured object sample according to the preset scanning speed and path, and the optical sensor 11 acquires the image information at different positions of the surface in real time according to the sampling frequency;
s5: and carrying out three-dimensional point cloud modeling on the axial heights of the plurality of sampling point information and the corresponding horizontal position coordinate information to generate a surface topography image.
The oblique illumination type color confocal measurement system projects test light to the surface of a measured object at an oblique angle, light with different wavelengths is focused to different axial heights, light spots are reflected to the other direction and then are totally reflected back to the measurement system through the reflection lens module, when the axial position of the measured object is changed, the light wavelength collected by the optical sensor is changed, the relative height change of the measured point is obtained by collecting the wavelength change of different sampling points, and the collection and calculation module carries out point cloud modeling on all the sampling points of the measured object to generate surface three-dimensional morphology information. The measurement system can realize the acquisition of two-dimensional outline and three-dimensional appearance information of the sample under the condition of the inclination angle.
The measuring system and the detecting method are suitable for detecting the surface appearance, the step height, the surface roughness, the flatness, the thickness of the transparent material and the like of a sample under the condition that the geometric space such as the surface appearance of the rotor blade of the aero-engine is limited.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. An oblique illumination type color confocal measurement system is characterized in that: the measuring system comprises a light source module, a dispersion lens module, a moving carrier module, a reflecting lens module and an acquisition and calculation module; the light source module faces the dispersion lens module; the dispersion lens module is provided with a linear incident light channel, and the reflection lens module is provided with a linear reflected light channel; the central extension lines of the incident light channel and the reflected light channel are intersected on the surface of the object to be measured loaded on the moving object carrying module; the incident light is obliquely emitted to the surface of the measured object loaded on the moving object carrying module; the included angle between the central line of the incident light and the normal line of the object carrying surface is an incident angle, and the incident angle is larger than the signal collecting angle of the dispersion lens module; the tail end of the reflecting lens module is a pyramid prism; a light collection channel is arranged on the side of the dispersion lens module and faces the collection calculation module; the acquisition and calculation module is also connected to the moving carrier module.
2. The oblique illumination confocal color measurement system of claim 1, wherein: the central line of the incident light channel and the central line of the reflected light channel are perpendicular to each other.
3. The oblique illumination confocal color measurement system of claim 1, wherein: the light source module comprises a light source (1), an incident optical fiber (2) and a first small hole mechanism (3-1); the first small hole mechanism (3-1) is provided with a first small hole; one end of the incident optical fiber is connected to the light source (1), and the other end of the incident optical fiber faces the first small hole and the dispersive lens module at the rear end of the first small hole.
4. The oblique illumination confocal color measurement system of claim 3, wherein: the dispersion lens module comprises a first dispersion tube lens (4-1), a second dispersion tube lens (4-2), a spectroscope (10) and a first objective lens (5-1); the first dispersion tube lens (4-1), the spectroscope (10) and the first objective lens (5-1) are sequentially arranged on an incident light path from front to back; the second dispersion tube lens (4-2) is arranged on the side of the spectroscope (10) to form the light collecting channel, and the light collecting channel is perpendicular to the incident light path; the incident angle of the incident light is larger than the signal collection angle of the first objective lens (5-1).
5. The oblique illumination confocal color measurement system of claim 1, wherein: the reflection lens module comprises a second objective lens (5-2), a collimating lens (8) and a pyramid prism (9) which are arranged on a reflection light path; the second objective lens (5-2), the collimating lens (8) and the pyramid prism (9) are arranged from near to far relative to the moving object carrying module.
6. The oblique illumination confocal color measurement system of claim 1, wherein: the moving carrier module comprises an X-Y displacement platform (7); the X-Y displacement platform (7) is provided with three overlapped moving layers, the bottom layer is fixed, the middle layer moves longitudinally relative to the bottom layer, the upper layer moves transversely relative to the middle layer, and the upper layer is used for loading a measured object (6).
7. The oblique illumination confocal color measurement system of claim 1, wherein: the acquisition and calculation module comprises a second small hole mechanism (3-2), an optical sensor (11) and a computer (12); the second small hole mechanism (3-2) is provided with a second small hole; the light of the light collection channel reaches the optical sensor (11) through the second small hole, the optical sensor (11) is connected to the computer (12), and the computer (12) is further connected to the moving object carrying module.
8. An oblique illumination type confocal color measurement method, which is applied to the oblique illumination type confocal color measurement system according to any one of claims 1 to 7, includes the following steps:
p1, the light source module emits a polychromatic light beam, the polychromatic light beam passes through the dispersion lens module, is dispersed into a plurality of light beams with different wavelengths, is focused on the surface of the measured object loaded on the moving object carrying module, and moves the moving object carrying module to acquire image information of each position on the surface of the measured object;
p2, incident light is reflected to the reflection lens module on the surface of the object to be measured, reflected by 180 degrees of the pyramid prism at the end of the reflection lens module, and returns to the moving carrier module;
p3, the light beam passing through the step P2 is reflected back to the incident light channel of the dispersion lens module, reflected to the light collection channel at the side of the dispersion lens module in the incident light channel, and finally emitted to the collection and calculation module; the acquisition and calculation module acquires the wavelength and color information of a focusing light spot reflected by the surface of the measured object, calculates the relative axial height data of the surface of the measured object by combining the wavelength information and the displacement information of the moving carrying module, and carries out three-dimensional point cloud modeling on the axial height of the sampling point information and the corresponding horizontal position coordinate information to generate a surface morphology image.
9. The oblique illumination type confocal color measurement method according to claim 8, applied to the oblique illumination type confocal color measurement system according to claim 4, wherein the step P1 specifically comprises:
the light source (1) emits polychromatic light, the polychromatic light is transmitted to the first small hole through the incident optical fiber (2) to generate a point light source, the polychromatic light of the point light source is dispersed into light beams with different wavelengths after passing through the first dispersion tube lens (4-1), the spectroscope (10) and the first objective lens (5-1), the light beams with different wavelengths are respectively focused on different optical path axial height positions of a measured object, and focuses of all the wavelengths are sequentially arranged at the axial positions according to wavelength changes; and scanning and sampling each position point on the surface of the measured object by controlling the moving track of the moving object carrying module.
10. The oblique illumination type confocal color measurement method according to claim 8, applied to the oblique illumination type confocal color measurement system according to claim 5, wherein the step P2 specifically comprises:
incident light is reflected to at the surface of testee the reflection lens module, and the reverberation loops through second objective (5-2) and collimating lens (8), and collimating lens (8) are gathered into the collimated beam with the light beam of diffusion and are transmitted to pyramid prism (9), and pyramid prism (9) are with 180 degrees original ways reflection back the thing module is carried in the motion.
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