A camera-based objective lens surface shape detection system and device

Abstract

The present invention belongs to the field of optical system surface shape detection, and specifically is a camera-based objective lens surface shape detection system and device, comprising an optical path device building module, a camera integration module, an in-axis field of view measurement module, an out-axis field of view measurement module, a detection result output module and a cloud database. The system first builds an optical path detection device to carry out preparatory work before the detection of an objective lens to be tested, implements optical path calibration work in the camera integrated optical path detection device, obtains the original wavefront aberration corresponding to the camera optical path calibration, then places the objective lens to be tested into the optical path detection device to carry out wavefront aberration measurement, obtains the wavefront aberration corresponding to the in-axis field of view and out-axis field of view of the objective lens to be tested, accurately outputs the surface shape detection result of the objective lens to be tested to effectively feedback the abnormal influence of the surface shape of the objective lens to be tested on the imaging quality, and not only has high applicability and reliability, but also significantly improves the accuracy and efficiency of objective lens detection.

Description

Technical Field

[0001] The present invention belongs to the field of optical system surface shape detection, and in particular relates to a camera-based objective lens surface shape detection system and device. Background Art

[0002] With the continuous development of optical technology, the surface accuracy of the objective lens has an increasingly significant impact on the imaging quality. In fields such as astronomical observation, microscopic imaging, and optical measurement, the surface error of the objective lens will directly lead to distortion and blur of the image, thereby affecting the accuracy and reliability of the data. Therefore, the precise detection of the objective lens surface has become a key link in improving the performance of the optical system.

[0003] In the prior art, there are also some related solutions that can be applied to objective lens surface shape detection. For example, China Patent Publication No. CN116989692A is a method and system for detecting the surface shape of an extreme ultraviolet lithography objective lens based on subwavelength structure computational holography. It obtains high-precision aspheric surface shape data of the extreme ultraviolet lithography objective lens through the design and application of subwavelength structure computational holograms. The detection accuracy can reach RMS less than 1nm, which is very beneficial for low-cost precise etching processing, and the phase modulation capability is greater than that of traditional step-type computational holograms.

[0004] Another Chinese patent publication number CN102095385B discloses a novel spherical absolute measurement system and method, which uses an electrically controlled translation stage to adjust the spherical reflector to be measured to the confocal position of the standard objective lens, controls the Fizeau interferometer to perform a surface shape detection on the spherical reflector to be measured at this position through a computer, and stores the detection data in the computer, then controls the electrically controlled translation stage through the computer to make the reflector to be measured generate confocal shears of Δx and Δy around the focus relative to the optical axis of the interferometer, and performs two more detections using the interferometer and stores the detection data in the computer. The surface shape data of the three detections are separated from the system error and the reference surface error by data processing software installed on the computer, thereby obtaining the absolute surface shape information of the optical mirror to be measured.

[0005] Although the above schemes put forward some solutions for applying to objective lens surface shape detection, the prior art still has the following limitations. Specifically, the prior art mostly relies on interferometers for objective lens surface shape detection. On the one hand, there are many restrictions on the external dimensions of the objective lens to be measured, making it difficult to achieve full-aperture surface shape detection, resulting in the inability to fully obtain the objective lens surface shape information. On the other hand, for optical systems in special bands such as the ultraviolet band, not only is the interferometer itself expensive, but the optical path construction and adjustment are extremely difficult, the versatility is poor, and the detection cost and operation difficulty are increased. In addition, the objective lens surface shape detection result is easily affected by external environmental factors, which reduces the accuracy and repeatability of the detection result. Summary of the invention

[0006] In order to overcome the shortcomings of the background technology, the embodiments of the present invention provide a camera-based objective lens surface shape detection system and device, which can effectively solve the problems involved in the above-mentioned background technology.

[0007] The purpose of the present invention can be achieved through the following technical solutions: The first aspect of the present invention provides a camera-based objective lens surface detection system, including: an optical path device building module, a camera integration module, an in-axis field of view measurement module, an out-of-axis field of view measurement module, a detection result output module and a cloud database.

[0008] The optical path device building module is connected to the camera integration module, the camera integration module is connected to the in-axis field of view measurement module, the in-axis field of view measurement module is connected to the out-axis field of view measurement module, the out-axis field of view measurement module is connected to the detection result output module, and the cloud database is connected to the camera integration module and the detection result output module respectively.

[0009] The optical path device building module is used to build an optical path detection device to prepare for the detection of the objective lens to be tested.

[0010] The camera integration module is used to implement the optical path calibration work in the camera integrated optical path detection device to obtain the original wavefront aberration corresponding to the camera optical path calibration.

[0011] The in-axis field of view measurement module is used to place the objective lens to be tested into the optical path detection device to measure the wavefront aberration, deduct the original wavefront aberration corresponding to the camera optical path calibration from the measured wavefront aberration, and obtain the wavefront aberration corresponding to the in-axis field of view of the objective lens to be tested.

[0012] The off-axis field of view measurement module is used to change the incident light angle by translating the translation stage of the objective lens to be tested and the multi-dimensional displacement stage in the optical path detection device, so as to monitor and obtain the wavefront aberration corresponding to the off-axis field of view shape of the objective lens to be tested.

[0013] The detection result output module is used to sort out the wavefront aberrations corresponding to the in-axis viewing field shape and the out-axis viewing field shape of the objective lens to be tested, and output the surface shape detection result of the objective lens to be tested.

[0014] The cloud database is used to store the standard centroid position coordinates of the ideal aberration-free state of the light spot, store the preset index parameters of the Zernike polynomials corresponding to various aberrations, and store the preset reasonable intensity ranges corresponding to various aberrations under the normal state of objective imaging quality.

[0015] The second aspect of the present invention provides a device, characterized in that it includes: a processor, a memory and a communication bus. The memory stores a computer-readable program that can be executed by the processor. The communication bus realizes the connection and communication between the processor and the memory. When the processor executes the computer-readable program, the camera-based objective lens surface shape detection system is realized.

[0016] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: (1) The optical path detection device of the present invention can be applied to the surface shape detection of objective lenses of various sizes and wavelength ranges, greatly broadening the scope of detectable objective lenses and having the advantages of versatility and adaptability.

[0017] (2) The present invention uses a camera to participate in the objective lens surface detection, which greatly weakens the influence of environmental factors on the objective lens surface detection results and increases the anti-interference ability of the objective lens surface detection process.

[0018] (3) The present invention integrates the wavefront aberrations corresponding to the on-axis field shape and the off-axis field shape of the objective lens to be tested, accurately outputs the surface shape detection result of the objective lens to be tested, and effectively feeds back the abnormal influence of the surface shape of the objective lens to be tested on the imaging quality, thereby significantly improving the accuracy and efficiency of objective lens detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0020] Figure 1 It is a schematic diagram of module connection of the present invention.

[0021] Figure 2 It is a schematic structural diagram of the projection objective optical path detection device of the present invention.

[0022] Figure 3 It is a schematic structural diagram of the infinite tube length objective lens optical path detection device of the present invention.

[0023] Figure numerals: 1. Laser; 2. Laser beam expansion unit; 3. Reflector; 4. Reflector; 5. Beam splitter; 6. Camera; 7. Wave plate; 8. Reflector; 9. Coupling mirror; 10. Focus of coupling mirror; 11. Projection objective lens; 12. Displacement stage for the objective lens to be tested; 13. Focus of the objective lens to be tested; 14. Bowl mirror; 15. Multi-dimensional displacement stage; 16. Optical path turning and extension unit; 17. Infinite tube length objective lens. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Reference Figure 1 As shown, the present invention provides a first aspect of a camera-based objective lens surface detection system, including: an optical path device building module, a camera integration module, an in-axis field of view measurement module, an out-of-axis field of view measurement module, a detection result output module and a cloud database.

[0026] The optical path device building module is connected to the camera integration module, the camera integration module is connected to the in-axis field of view measurement module, the in-axis field of view measurement module is connected to the out-axis field of view measurement module, the out-axis field of view measurement module is connected to the detection result output module, and the cloud database is connected to the camera integration module and the detection result output module respectively.

[0027] The optical path device building module is used to build an optical path detection device to perform preparation work before detecting the object lens to be tested.

[0028] Specifically, the specific process of the preparation work before the test of the objective lens to be tested includes: A1, fixing the laser, and adaptively adjusting the optical path turning extension unit according to the three-dimensional size of the objective lens to be tested, ensuring that the optical path length matches the detection requirements of the objective lens to be tested, and the optical axis direction of the optical path turning mirror is the same as the optical axis direction of the objective lens to be tested.

[0029] It should be noted that the above optical path length must match the detection requirements of the objective lens to be tested under the following conditions: the optical path length is a preset multiple of the focal length of the objective lens to be tested.

[0030] A2. Select the plane above the coupling mirror as the reference plane, place a flat crystal to force the incident laser light to return along the original path to determine the position of the optical axis, place a small hole above the coupling mirror and combine it with each reflector to perform optical axis calibration to ensure that the laser optical axis is coaxial with the coupling mirror optical axis.

[0031] A3. Introduce and adjust each optical component to fix the position of the output optical axis.

[0032] It should be noted that the above-mentioned optical components include a laser beam expansion unit, a beam splitter and a wave plate.

[0033] The optical path detection device of the embodiment of the present invention can be applied to the surface shape detection of objective lenses of various sizes and various wavelength ranges, which greatly broadens the scope of detectable objective lenses and has the advantages of versatility and adaptability.

[0034] The camera integration module is used to implement the optical path calibration work in the camera integrated optical path detection device to obtain the original wavefront aberration corresponding to the camera optical path calibration.

[0035] It should be noted that the above optical path calibration work is not static, but varies according to the type of objective lens to be tested. In actual operation, the specific calibration process, parameter settings, and technical means used can be referred to the relevant optical instrument operation manual, industry standard specifications, or specific objective lens technical documents.

[0036] Specifically, the specific acquisition process of the original wavefront aberration corresponding to the camera optical path calibration includes: the camera receives the incident light returned by the original path of the laser, the camera's built-in microlens array decomposes the incident light and focuses the image sensor to convert it into a light spot array diagram, obtains the centroid position coordinates of each light spot in the light spot array diagram and analyzes its offset relative to the ideal position coordinates, reconstructs the wavefront through Zernike polynomial fitting, and obtains the wavefront function corresponding to the camera optical path calibration.

[0037] The preset index parameters of the Zernike polynomials corresponding to various aberrations stored in the cloud database are sequentially substituted into the wavefront function corresponding to the camera optical path calibration to obtain the various aberration intensities corresponding to the camera optical path calibration, which are collectively used as the original wavefront aberrations corresponding to the camera optical path calibration.

[0038] Exemplarily, the above-mentioned various types of aberrations include but are not limited to piston, tilt, defocus, coma, astigmatism, secondary defocus, etc.

[0039] Specifically, the specific process of obtaining the centroid position coordinates of each light spot in the light spot array diagram includes: traversing each pixel point covered by each light spot in the light spot array diagram, and obtaining the image grayscale value of each pixel point covered by each light spot. And its position coordinates in the image coordinate system ,in is the number of each light spot, , is the number of each pixel, , respectively, by the formula , The horizontal coordinate and the vertical coordinate of the centroid position of each light spot in the light spot array diagram are determined, and then the centroid position coordinates of each light spot in the light spot array diagram are obtained.

[0040] Specifically, the specific analysis process of the offset of the centroid position coordinates of each light spot in the light spot array diagram relative to the ideal position coordinates includes: converting the centroid position coordinates of each light spot in the light spot array diagram according to the preset pixel size of the camera's built-in image sensor and the preset magnification of the light path detection device.

[0041] It should be noted that the preset magnification of the above-mentioned optical path detection device refers to the degree of magnification from the incident light of the laser to the image formed on the image sensor in the camera, which is the ratio of the size of the image to the size of the object, and can be directly input and uploaded by the design engineer of the optical path detection device.

[0042] Extract the standard centroid position coordinates of the ideal aberration-free state of the spot stored in the cloud database , respectively, by the formula , Analyze the wavefront slopes corresponding to the horizontal and vertical directions of the centroid positions of each light spot in the light spot array diagram relative to the ideal position, where is the preset focal length of the built-in microlens of the camera, and the wavefront slopes corresponding to the horizontal and vertical directions of the centroid position relative to the ideal position are taken as the offset of the centroid position coordinates relative to the ideal position coordinates, thereby obtaining the offset of the centroid position coordinates of each light spot in the light spot array diagram relative to the ideal position coordinates.

[0043] It should be noted that the preset pixel size of the built-in image sensor of the above-mentioned camera and the preset focal length of the built-in microlens can be specifically referred to the technical manual provided by the camera manufacturer.

[0044] Specifically, the specific acquisition process of the wavefront function corresponding to the camera optical path calibration includes: converting the centroid position coordinates of each light spot in the light spot array diagram into polar coordinates , construct the wavefront function , ,in are the Zernike polynomial coefficients, is the Zernike polynomial, are index parameters of the Zernike polynomials, satisfying is an even number and , Constraints, The polar diameter variable and polar angle variable are used respectively. The partial derivatives of the wavefront function are calculated in the horizontal and vertical directions respectively. The overall comparison error function between the wavefront slopes in the horizontal and vertical directions of each spot in the spot array diagram and the theoretical wavefront slopes in the corresponding calculation direction of the Zernike polynomial is constructed. , the specific form is , solve the Zernike polynomial coefficients and substitute them into the wavefront function to obtain the wavefront function corresponding to the camera optical path calibration.

[0045] The in-axis field of view measurement module is used to place the objective lens to be tested into the optical path detection device to measure the wavefront aberration, deduct the original wavefront aberration corresponding to the camera optical path calibration from the measured wavefront aberration, and obtain the wavefront aberration corresponding to the in-axis field of view of the objective lens to be tested.

[0046] The off-axis field of view measurement module is used to monitor and obtain the wavefront aberration corresponding to the off-axis field of view of the objective lens to be tested by translating the translation stage and the multi-dimensional displacement stage in the optical path detection device to change the incident light angle.

[0047] Specifically, the specific acquisition process of the wavefront aberration corresponding to the off-axis viewing field shape of the objective lens to be measured includes: taking the preset deviation angle between the laser incident light angle and the optical axis of the objective lens to be measured as the reference angle, accumulating in sequence to determine each changed incident light angle, constructing a corresponding wavefront function under each changed incident light angle, setting the corresponding influence weight of each changed incident light angle, and accumulating the product of the wavefront function constructed under each changed incident light angle and its corresponding influence weight to obtain the wavefront function corresponding to the off-axis viewing field shape of the objective lens to be measured, which is consistent with the method for obtaining the original wavefront aberration corresponding to the above-mentioned camera optical path calibration, and obtaining the wavefront aberration corresponding to the off-axis viewing field shape of the objective lens to be measured.

[0048] The embodiment of the present invention uses a camera to participate in the objective lens surface shape detection, which greatly weakens the influence of environmental factors on the objective lens surface shape detection result and increases the anti-interference ability of the objective lens surface shape detection process.

[0049] The detection result output module is used to sort out the wavefront aberrations corresponding to the in-axis viewing surface shape and the out-axis viewing surface shape of the objective lens to be tested, and output the surface shape detection result of the objective lens to be tested.

[0050] Specifically, the specific output process of the surface shape detection result of the objective lens to be tested includes: comparing the various aberration intensities corresponding to the in-axis viewing field shape and the out-axis viewing field shape of the objective lens to be tested with the preset reasonable intensity ranges corresponding to various aberrations under the normal state of objective lens imaging quality stored in the cloud database, analyzing the imaging quality abnormality influence index of the in-axis viewing field shape and the out-axis viewing field shape of the objective lens to be tested, and taking the two together as the surface shape detection output result of the objective lens to be tested.

[0051] Specifically, the specific analysis process of the imaging quality abnormality influence index of the in-axis viewing field shape of the objective lens to be tested includes: if the intensity of a certain type of aberration corresponding to the in-axis viewing field shape of the objective lens to be tested is within the preset reasonable intensity interval corresponding to it when the imaging quality of the objective lens is normal, then the imaging abnormality influence degree of this type of aberration is set to 0; conversely, if the intensity of a certain type of aberration corresponding to the in-axis viewing field shape of the objective lens to be tested is outside the preset reasonable intensity interval corresponding to it when the imaging quality of the objective lens is normal, then the deviation ratio of the intensity of this type of aberration corresponding to the in-axis viewing field shape of the objective lens to be tested relative to its corresponding preset reasonable intensity interval is calculated, and this is used as the imaging abnormality influence degree of this type of aberration, and the imaging quality influence weights of various types of aberrations are set, and the products of the imaging abnormality influence degrees of various types of aberrations corresponding to the in-axis viewing field shape of the objective lens to be tested and their imaging quality influence weights are accumulated to obtain the imaging quality abnormality influence index of the in-axis viewing field shape of the objective lens to be tested.

[0052] It should be noted that the specific calculation process of the deviation ratio of the intensity of this type of aberration corresponding to the visual field shape in the axis of the objective lens to be tested relative to the corresponding preset reasonable intensity interval is as follows: if the intensity of this type of aberration corresponding to the visual field shape in the axis of the objective lens to be tested is greater than the upper limit value of the corresponding preset reasonable intensity interval, then the difference between the intensity of this type of aberration corresponding to the visual field shape in the axis of the objective lens to be tested and the upper limit value of the corresponding preset reasonable intensity interval is divided by the upper limit value of the corresponding preset reasonable intensity interval to obtain the deviation ratio of the intensity of this type of aberration corresponding to the visual field shape in the axis of the objective lens to be tested relative to the corresponding preset reasonable intensity interval; if the intensity of this type of aberration corresponding to the visual field shape in the axis of the objective lens to be tested is less than the lower limit value of the corresponding preset reasonable intensity interval, then the absolute difference between the intensity of this type of aberration corresponding to the visual field shape in the axis of the objective lens to be tested and the lower limit value of the corresponding preset reasonable intensity interval is divided by the lower limit value of the corresponding preset reasonable intensity interval to obtain the deviation ratio of the intensity of this type of aberration corresponding to the visual field shape in the axis of the objective lens to be tested relative to the corresponding preset reasonable intensity interval.

[0053] It should also be noted that the analysis process of the imaging quality abnormality influence index of the off-axis viewing field shape of the objective lens to be tested is consistent with the analysis process of the imaging quality abnormality influence index of the on-axis viewing field shape of the objective lens to be tested, and will not be repeated here.

[0054] The embodiment of the present invention comprehensively analyzes the wavefront aberrations corresponding to the on-axis field shape and the off-axis field shape of the objective lens to be tested, accurately outputs the surface shape detection result of the objective lens to be tested, and effectively feeds back the abnormal influence of the surface shape of the objective lens to be tested on the imaging quality, thereby significantly improving the accuracy and efficiency of objective lens detection.

[0055] The cloud database is used to store the standard centroid position coordinates of the light spot in an ideal aberration-free state, store preset index parameters of Zernike polynomials corresponding to various aberrations, and store preset reasonable intensity ranges corresponding to various aberrations in a normal state of objective lens imaging quality.

[0056] It should be noted that all storage parameters in the above cloud database are derived from system development and implantation.

[0057] The second aspect of the present invention provides a device, characterized in that it includes: a processor, a memory and a communication bus. The memory stores a computer-readable program that can be executed by the processor. The communication bus realizes the connection and communication between the processor and the memory. When the processor executes the computer-readable program, the camera-based objective lens surface shape detection system is realized.

[0058] By way of example, specific examples of the adjustment and surface shape detection of the optical path detection device for a projection objective lens and an infinite length objective lens are presented below.

[0059] Reference Figure 2As shown, projection objective: fix the laser, confirm the three-dimensional size of the projection objective, install and adjust the optical path turning extension unit so that the optical path length meets the detection size requirements of the projection objective, adjust the optical path turning mirror so that the optical axis direction is the same as that of the projection objective, take the plane above the coupling mirror as the reference plane, place the flat crystal, return the laser along the original path, and confirm the optical axis. Place a small hole above the coupling mirror, adjust the three reflectors so that the optical axis of the laser is coaxial with the optical axis of the coupling mirror, put in the laser beam expansion unit, the beam splitter and the wave plate and adjust the position so that the position of the output optical axis remains unchanged, add a camera to receive the light reflected back by the flat crystal, adjust the camera position so that the camera center is coaxial with the optical axis, remove the flat crystal, place the bowl mirror under the coupling mirror, adjust the height and translation of the bowl mirror so that the focus of the coupling mirror coincides with the spherical center of the bowl mirror, and the laser returns along the original path and is received by the camera. Detect and record the wavefront aberration of the optical path at this time, and complete the optical path calibration.

[0060] Remove the bowl mirror and connect it to the multi-dimensional translation stage, connect the projection objective lens to the projection objective lens translation stage and put it into the detection light path, adjust the position of the projection objective lens so that the optical axis of the projection objective lens coincides with the optical axis of the detection light path, place the bowl mirror and the multi-dimensional translation stage together under the objective lens, and adjust the multi-dimensional translation stage to make the center of the bowl mirror coincide with the focus of the projection objective lens. At this time, the light returns along the original path and is received by the camera. Through fine adjustment of the multi-dimensional translation stage, the camera measures the wavefront aberration of the detection light path. The wavefront aberration of the projection objective lens can be obtained by subtracting the original aberration of the calibration light path from the detection result. The surface shape of the off-axis field of view of the projection objective lens can be detected by translating the projection objective lens translation stage and the multi-dimensional translation stage.

[0061] Reference Figure 3 As shown, infinite barrel length objective lens: the adjustment operation of the infinite barrel length objective lens optical path detection device is different from the adjustment operation of the projection objective lens only in the optical path calibration work, and its optical path calibration work is: remove the flat crystal and the coupling mirror to allow the collimated parallel light to pass directly, connect the infinite barrel length objective lens to the infinite barrel length objective lens displacement stage and put it into the detection optical path, adjust the position of the infinite barrel length objective lens so that its optical axis coincides with the optical axis of the detection optical path, connect the bowl mirror to the multi-dimensional displacement stage, and place them together under the infinite barrel length objective lens, and through the adjustment of the multi-dimensional displacement stage, make the center of the bowl mirror coincide with the focus of the infinite barrel length objective lens, then the light returns along the original path and is received by the camera, and the wavefront aberration of the optical path at this time is detected and recorded, thereby completing the optical path calibration work.

[0062] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A camera-based objective lens surface detection system, characterized in that: include: An optical path device building module is used to build an optical path detection device to prepare for the detection of the objective lens to be tested; A camera integration module is used to implement optical path calibration in the camera integrated optical path detection device to obtain the original wavefront aberration corresponding to the camera optical path calibration; The in-axis field of view measurement module is used to place the objective lens to be tested into the optical path detection device to measure the wavefront aberration, deduct the original wavefront aberration corresponding to the camera optical path calibration from the measured wavefront aberration, and obtain the wavefront aberration corresponding to the in-axis field of view of the objective lens to be tested; The off-axis field of view measurement module is used to change the incident light angle by translating the translation stage of the objective lens to be tested and the multi-dimensional displacement stage in the optical path detection device, so as to monitor and obtain the wavefront aberration corresponding to the off-axis field of view of the objective lens to be tested; The detection result output module is used to sort out the wavefront aberrations corresponding to the in-axis and out-axis viewing field shapes of the objective lens to be tested, and output the surface shape detection results of the objective lens to be tested; The cloud database is used to store the standard centroid position coordinates of the ideal aberration-free state of the light spot, the preset index parameters of the Zernike polynomials corresponding to various aberrations, and the preset reasonable intensity ranges corresponding to various aberrations under the normal state of the objective imaging quality; The specific output process of the surface shape detection result of the objective lens to be tested includes: comparing the various aberration intensities corresponding to the in-axis field shape and the out-axis field shape of the objective lens to be tested with the preset reasonable intensity ranges corresponding to the various aberrations under the normal state of objective lens imaging quality stored in the cloud database, analyzing the imaging quality abnormality influence index of the in-axis field shape and the out-axis field shape of the objective lens to be tested, and taking the two together as the surface shape detection output result of the objective lens to be tested.

2. The camera-based objective lens surface detection system according to claim 1, characterized in that: The specific process of the preparation work before the test of the objective lens to be tested includes: A1, fixing the laser, and adaptively adjusting the optical path turning extension unit according to the three-dimensional size of the objective lens to be tested, ensuring that the optical path length matches the test requirements of the objective lens to be tested, and the optical axis direction of the optical path turning mirror is the same as the optical axis direction of the objective lens to be tested; A2. Select the plane above the coupling mirror as the reference plane, place a flat crystal to force the incident laser light to return along the original path to determine the optical axis position, place a small hole above the coupling mirror and combine with each reflector to perform optical axis calibration to ensure that the laser optical axis is coaxial with the coupling mirror optical axis; A3. Introduce and adjust each optical component to fix the position of the output optical axis.

3. The camera-based objective lens surface detection system according to claim 1, characterized in that: The specific acquisition process of the original wavefront aberration corresponding to the camera optical path calibration includes: the camera receives the incident light returned by the original path of the laser, the camera's built-in microlens array decomposes the incident light and focuses the image sensor to convert it into a light spot array diagram, obtains the centroid position coordinates of each light spot in the light spot array diagram and analyzes the offset relative to the ideal position coordinates, reconstructs the wavefront by Zernike polynomial fitting, and obtains the wavefront function corresponding to the camera optical path calibration; The preset index parameters of the Zernike polynomials corresponding to various aberrations stored in the cloud database are sequentially substituted into the wavefront function corresponding to the camera optical path calibration to obtain the various aberration intensities corresponding to the camera optical path calibration, which are collectively used as the original wavefront aberrations corresponding to the camera optical path calibration.

4. The camera-based objective lens surface detection system according to claim 3, characterized in that: The specific process of obtaining the centroid position coordinates of each light spot in the light spot array diagram includes: traversing each pixel point covered by each light spot in the light spot array diagram, and obtaining the image grayscale value of each pixel point covered by each light spot. And its position coordinates in the image coordinate system ,in is the number of each light spot, , is the number of each pixel, , respectively, by the formula , The horizontal coordinate and the vertical coordinate of the centroid position of each light spot in the light spot array diagram are determined, and then the centroid position coordinates of each light spot in the light spot array diagram are obtained.

5. The camera-based objective lens surface detection system according to claim 4, characterized in that: The specific analysis process of the offset of the centroid position coordinates of each light spot in the light spot array diagram relative to the ideal position coordinates includes: converting the centroid position coordinates of each light spot in the light spot array diagram according to the preset pixel size of the built-in image sensor of the camera and the preset magnification of the light path detection device; Extract the standard centroid position coordinates of the ideal aberration-free state of the spot stored in the cloud database , respectively, by the formula , Analyze the wavefront slopes corresponding to the horizontal and vertical directions of the centroid positions of each light spot in the light spot array diagram relative to the ideal position, where is the preset focal length of the built-in microlens of the camera, and the wavefront slopes corresponding to the horizontal and vertical directions of the centroid position relative to the ideal position are taken as the offset of the centroid position coordinates relative to the ideal position coordinates, thereby obtaining the offset of the centroid position coordinates of each light spot in the light spot array diagram relative to the ideal position coordinates.

6. The camera-based objective lens surface detection system according to claim 5, characterized in that: The specific acquisition process of the wavefront function corresponding to the camera optical path calibration includes: converting the centroid position coordinates of each light spot in the light spot array diagram into polar coordinates , construct the wavefront function , ,in are the Zernike polynomial coefficients, is the Zernike polynomial, are index parameters of the Zernike polynomials, satisfying is an even number and , Constraints, The polar diameter variable and polar angle variable are used respectively. The partial derivatives of the wavefront function are calculated in the horizontal and vertical directions respectively. The overall comparison error function between the wavefront slopes in the horizontal and vertical directions of each spot in the spot array diagram and the theoretical wavefront slopes in the corresponding calculation direction of the Zernike polynomial is constructed. , the specific form is , solve the Zernike polynomial coefficients and substitute them into the wavefront function to obtain the wavefront function corresponding to the camera optical path calibration.

7. The camera-based objective lens surface detection system according to claim 3, characterized in that: The specific acquisition process of the wavefront aberration corresponding to the off-axis viewing field shape of the objective lens to be tested includes: taking the preset deviation angle between the laser incident light angle and the optical axis of the objective lens to be tested as the reference angle, accumulating in sequence to determine each changed incident light angle, constructing a corresponding wavefront function under each changed incident light angle, setting the corresponding influence weight of each changed incident light angle, and accumulating the product of the wavefront function constructed under each changed incident light angle and its corresponding influence weight to obtain the wavefront function corresponding to the off-axis viewing field shape of the objective lens to be tested, which is consistent with the method for obtaining the original wavefront aberration corresponding to the above-mentioned camera optical path calibration, and obtains the wavefront aberration corresponding to the off-axis viewing field shape of the objective lens to be tested.

8. The camera-based objective lens surface detection system according to claim 1, characterized in that: The specific analysis process of the imaging quality abnormality influence index of the intra-axial viewing field shape of the objective lens to be tested includes: if the intensity of a certain type of aberration corresponding to the intra-axial viewing field shape of the objective lens to be tested is within the preset reasonable intensity interval corresponding to it when the imaging quality of the objective lens is normal, then the imaging abnormality influence degree of this type of aberration is set to 0; conversely, if the intensity of a certain type of aberration corresponding to the intra-axial viewing field shape of the objective lens to be tested is outside the preset reasonable intensity interval corresponding to it when the imaging quality of the objective lens is normal, then the deviation ratio of the intensity of this type of aberration corresponding to the intra-axial viewing field shape of the objective lens to be tested relative to the corresponding preset reasonable intensity interval is calculated, and this is used as the imaging abnormality influence degree of this type of aberration, and the imaging quality influence weights of various types of aberrations are set, and the products of the imaging abnormality influence degrees of various types of aberrations corresponding to the intra-axial viewing field shape of the objective lens to be tested and the imaging quality influence weights are accumulated to obtain the imaging quality abnormality influence index of the intra-axial viewing field shape of the objective lens to be tested.

9. A device, characterized in that: include: Processor, memory and communication bus: the memory stores a computer-readable program that can be executed by the processor; the communication bus realizes the connection and communication between the processor and the memory; When the processor executes the computer-readable program, the camera-based objective lens surface detection system as described in any one of claims 1-8 is implemented.

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