A method and device for calibrating core parameters of a Shack-Hartmann wavefront sensor

Abstract

The present application relates to the field of optical precision detection technology, especially to a Shack-Hartmann wavefront sensor core parameter calibration method and device, through the superposition calibration based on plane wave and spherical wave, the micro-lens array and camera target surface distance, micro-lens unit size which are strongly related to detection accuracy can be obtained, and the theoretical model has high precision.In the calibration scheme, by removing / adding a microscope objective, simple and fast switching based on plane wave and spherical wave can be realized, and the introduced error source is very small.In the calibration scheme, high-precision angle monitoring based on a collimator and high-precision displacement monitoring based on a displacement sensor are set, thereby ensuring high-precision calibration.

Description

Technical Field

[0001] This invention belongs to the field of optical precision detection technology, and in particular relates to a method and apparatus for calibrating the core parameters of a Shaker-Hartmann wavefront sensor. Background Technology

[0002] The Shakhartmann wavefront sensor is a wavefront detection instrument based on slope measurement, and calibration is usually required to obtain high-precision detection results. The Shakhartmann wavefront sensor mainly consists of a microlens array and a photodetector. The microlens array divides the beam to be measured into several sub-apertures. The beam passing through each sub-aperture forms a spot on the photodetector. The position of the spot is related to the average slope of the wavefront corresponding to the sub-aperture. By utilizing the positional offset of the spots from all sub-apertures, the wavefront slope distribution of the measured wavefront can be obtained. Using a wavefront reconstruction algorithm, the phase distribution of the measured wavefront can be obtained. A schematic diagram is shown below. Figure 1 As shown, the wavefront slope can be expressed as:

[0003] As can be seen from the above equation, the wavefront slope is calculated from the displacement of the light spot and the distance between the microlens array and the photodetector. During wavefront reconstruction, the wavefront phase distribution is solved from the wavefront slope. The microlens unit size is a core parameter that affects the accuracy of wavefront reconstruction. This paper proposes a combined calibration method to address the two core parameters strongly correlated with detection accuracy: the distance between the microlens array and the photodetector, and the microlens array unit size. This method enables high-precision calibration.

[0004] Commonly used Shakhartmann wavefront sensor calibration methods include plane wave-based calibration, spherical wave-based calibration, and phase plate-based calibration, among which phase plate-based calibration has relatively poor accuracy. Plane wave-based and spherical wave-based calibrations involve using the Shakhartmann wavefront sensor to be calibrated to detect plane waves or spherical waves, changing the slope of the wavefront during the process, and achieving calibration of some parameters through a series of detections.

[0005] The Chinese literature publication "Wang Yanping, Wang Qianqian, Ma Chong. Research on Calibration Method of Hartmann Wavefront Analyzer [J]. Chinese Journal of Lasers, 2015, 42(1): 0108003" mentions that plane wave-based calibration involves changing the angle between the plane wave and the Shak-Hartmann wavefront sensor during the process, thereby changing the wavefront slope. Through a series of tests, the distance between the microlens array and the photodetector can be calibrated. Wang Yanping et al. introduced a plane wave-based Shak-Hartmann wavefront sensor calibration method, which can obtain the true distance between the microlens array and the CCD through calibration, thereby improving the accuracy of wavefront slope calculation. However, changing the plane wave angle by translating the point light source at the focal point has poor accuracy.

[0006] The Chinese literature document "Research on Development and Calibration Technology of High-Precision Hartmann-Shack Wavefront Sensor_Bao Mingdi" mentions that spherical wave-based calibration can usually obtain a large number of calibration parameters, including the distance between the microlens array and the photodetector, the size of the microlens unit, and the pixel size of the photodetector. However, the theoretical models for spherical wave-based calibration often have large errors in their approximations and iterations, making it difficult to achieve high-precision calibration. Bao Mingdi et al. proposed a spherical wave-based calibration method that uses an approximate and iterative theoretical model with large errors to solve for the calibration parameters.

[0007] In existing technical solutions, calibration based on plane waves can only obtain one parameter: the distance between the microlens array and the photodetector. Furthermore, the change in wavefront slope during calibration is usually not very accurate, thus affecting the final calibration result. Calibration based on spherical waves suffers from significant errors in the theoretical model, making it impossible to guarantee high-precision calibration results. Additionally, substantial errors exist in the actual calibration process. Summary of the Invention

[0008] In view of this, the present invention aims to provide a method and apparatus for calibrating the core parameters of a Shaker-Hartmann wavefront sensor.

[0009] To achieve the above objectives, the technical solution created by this invention is implemented as follows: A method for calibrating the core parameters of a Shaker-Hartmann wavefront sensor, comprising: Based on the plane wave calibration theoretical model and the spherical wave calibration theoretical model, a calibration experimental device was established in advance; When calibrating a plane wave, the distance between the microlens array and the camera target surface is obtained based on the plane wave calibration theoretical model. When calibrating spherical waves, the microlens unit size is obtained based on the spherical wave calibration theoretical model.

[0010] Furthermore, the calibration experimental setup pre-established based on the plane wave calibration theoretical model and the spherical wave calibration theoretical model includes: The calibration experimental setup uses an off-axis parabolic collimator to provide plane waves, and an infinity imaging microscope objective is mounted on the off-axis parabolic collimator to provide spherical waves. The Shakhartmann wavefront sensor to be calibrated is mounted on a turntable, which is then mounted on a translation mechanism. A double-sided mirror is mounted on the top of the Shakhartmann wavefront sensor to be calibrated. The left side works with a displacement sensor to perform high-precision monitoring of displacement during spherical wave calibration, while the right side works with an autocollimator to perform high-precision monitoring of rotation angle during plane wave calibration. The calibration experimental setup is stably mounted on an optical platform.

[0011] Furthermore, the plane wave calibration theoretical model includes: Based on the theoretical model of plane wave calibration, the incident wavefront slope of the plane wave is precisely changed, and the position of the centroid of the photodetector spot will also move accordingly. By knowing the change in wavefront slope and the movement of the centroid of the spot, the distance between the microlens array and the camera target surface can be accurately calculated. because xy Consistency of direction, here taken as y Taking direction as an example, the two detections before and after precisely changing the slope can be represented as:

[0012] in, S It is the slope of the incident wavefront, Δ y The amount of movement of the light spot, f It is the distance between the lens array and the camera target surface; During the calibration process, the difference between the two wavefront slopes is precisely known:

[0013] Therefore, we get:

[0014] The distance between the microlens array and the camera target surface f The calculation formula is expressed as: .

[0015] Furthermore, the theoretical model for spherical wave calibration includes: Based on the spherical wave calibration theoretical model, the distance between the spherical wave and the Shack-Hartmann wavefront sensor is precisely changed, that is, the radius of curvature of the spherical wave is changed, thereby achieving a precise change in the slope of the wavefront to be measured. The position of the centroid of the light spot on the photodetector will also move accordingly. The size of the microlens unit is calibrated by the precisely known change in the distance between the spherical wave and the Shack-Hartmann wavefront sensor and the movement of the position of the centroid of the light spot. The calculation process uses the precisely calibrated distance between the microlens array and the camera target surface. Spherical wavefront representation

[0016] Based on the working principle of the Shaker-Hartmann wavefront sensor, namely the calculation relationship between the spot displacement and the wavefront slope, we obtain:

[0017] Where Δ is the displacement of the light spot's centroid. f It is the distance between the microlens array and the camera target surface. Z It is the distance between the spherical wave point light source and the Shackhartmann wavefront sensor, and is used as the radius of curvature of the spherical wave; When the incident light wave is a spherical wave, the distance between adjacent light spots on the photodetector is expressed as:

[0018] in, D It is the size of the microlens unit;

[0019]

[0020]

[0021] The size of the microlens unit D It can be obtained from the following formula: ; Among them, the change in the radius of curvature of the spherical wave Δ Z The distance between the Shackletmann wavefront sensor microlens array and the camera target surface f Microlens unit size D Distance between adjacent light spots Q The relationship between Δ Z , f and Q It is known.

[0022] Furthermore, during the calibration of the plane wave, the distance between the microlens array and the camera target surface obtained based on the plane wave calibration theoretical model includes: A plane wave-based calibration is performed to obtain the distance between the microlens array and the camera target surface. No microscope objective is installed at the output port of the off-axis parabolic collimator. The emitted parallel light is then projected onto the Shaker-Hartmann wavefront sensor to be calibrated. A turntable is controlled to rotate the wavefront sensor, thereby changing the slope of the wavefront to be measured. Simultaneously, a high-precision rotation angle is monitored using an autocollimator. The actual rotation angle is based on the autocollimator reading. By detecting the wavefront at two angular positions and combining this with the plane wave calibration theoretical model, the distance between the microlens array and the camera target surface is obtained.

[0023] Furthermore, when calibrating spherical waves, the microlens unit size obtained based on the spherical wave calibration theoretical model includes: To perform calibration based on spherical waves, the microscope objective is mounted at the light outlet of a collimator, and a spherical wave is projected onto the wavefront sensor. The distance between the wavefront sensor to be calibrated and the microscope objective is changed by a translation mechanism, thereby changing the radius of curvature of the wavefront to be measured. At the same time, a displacement sensor is used for high-precision displacement monitoring, and the actual displacement is based on the reading of the displacement sensor. By detecting the wavefront at two positions and combining it with the spherical wave calibration theoretical model, the size of the microlens unit is obtained.

[0024] A calibration device for the core parameters of a Shaker-Hartmann wavefront sensor, comprising: Establish a unit for pre-establishing a calibration experimental setup based on the plane wave calibration theoretical model and the spherical wave calibration theoretical model; The first calibration unit is used to obtain the distance between the microlens array and the camera target surface based on the plane wave calibration theoretical model when calibrating the plane wave. The second calibration unit is used to obtain the microlens unit size based on the spherical wave calibration theoretical model when calibrating spherical waves.

[0025] Compared with the prior art, the present invention can achieve the following beneficial effects: This invention provides a calibration method and apparatus for the core parameters of a Shaker-Hartmann wavefront sensor. Through calibration based on the superposition of plane waves and spherical waves, it can obtain the distance between the microlens array and the camera target surface, and the size of the microlens units, which are strongly correlated with detection accuracy. The theoretical model possesses high accuracy. In the calibration scheme, simple and rapid switching between plane wave and spherical wave-based methods can be achieved by removing / adding microscope objectives, introducing very few error sources. The calibration scheme incorporates high-precision angle monitoring based on an autocollimator and high-precision displacement monitoring based on a displacement sensor, thereby ensuring high-precision calibration. Attached Figure Description

[0026] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram illustrating the phase distribution principle of the wavefront under test in existing technologies.

[0027] Figure 2 This is a flowchart illustrating a method for calibrating the core parameters of a Shaker-Hartmann wavefront sensor, as described in an embodiment of the present invention.

[0028] Figure 3 This is a schematic diagram of the calibration experimental apparatus in a calibration method for the core parameters of a Shaker-Hartmann wavefront sensor, as described in an embodiment of the present invention.

[0029] Figure 4 This is a schematic diagram illustrating the principle of plane wave calibration in a calibration method for the core parameters of a Shaker-Hartmann wavefront sensor, as described in an embodiment of the present invention.

[0030] Figure 5 This is a schematic diagram illustrating the principle of spherical wave calibration in a calibration method for the core parameters of a Shaker-Hartmann wavefront sensor, as described in an embodiment of the present invention.

[0031] Figure 6This is a structural block diagram of a calibration device for the core parameters of a Shaker-Hartmann wavefront sensor, as described in an embodiment of the present invention.

[0032] Explanation of reference numerals in the attached figures: Optical platform 1, translation mechanism 2, turntable 3, Shaker-Hartmann wavefront sensor to be calibrated 4, double-sided mirror 5, autocollimator 6, microscope objective 7, off-axis parabolic collimator 8, displacement sensor 9. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0035] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0036] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0037] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0038] Combination Figure 2As shown in the figure, this embodiment of the invention provides a method for calibrating the core parameters of a Shaker-Hartmann wavefront sensor, including: S110. Based on the plane wave calibration theory model and the spherical wave calibration theory model, a calibration experimental device is established in advance.

[0039] S120. When calibrating the plane wave, the distance between the microlens array and the camera target surface is obtained based on the plane wave calibration theoretical model.

[0040] S130. When calibrating spherical waves, the microlens unit size is obtained based on the spherical wave calibration theoretical model.

[0041] Combination Figure 3 As shown, in S110, the calibration experimental setup pre-established based on the plane wave calibration theoretical model and the spherical wave calibration theoretical model includes: The calibration experimental apparatus uses an off-axis parabolic collimator 8 to provide plane waves, and an infinity imaging microscope objective 7 is mounted on the off-axis parabolic collimator 8 to provide spherical waves. The Shakhartmann wavefront sensor 4 to be calibrated is mounted on a turntable 3, which is then mounted on a translation mechanism 2. A double-sided reflector 5 is mounted on the top of the Shakhartmann wavefront sensor 4 to be calibrated. The left side works with a displacement sensor 9 to perform high-precision monitoring of displacement during spherical wave calibration, while the right side works with an autocollimator 6 to perform high-precision monitoring of rotation angle during plane wave calibration. The calibration experimental apparatus is stably mounted on an optical platform 1.

[0042] First, an off-axis parabolic collimator 8 is selected as the plane wave source. This collimator features high precision and low aberration, providing high-quality plane waves. An infinity imaging microscope objective 7 is mounted at the exit port of the off-axis parabolic collimator 8 (disassembled during plane wave calibration and installed during spherical wave calibration) to provide spherical waves. The Shakhartmann wavefront sensor 4 to be calibrated is mounted on a turntable 3, which has high-precision rotation control capabilities, allowing for precise changes in the wavefront sensor's angle. The turntable 3 is then mounted on a translation mechanism 2, which enables precise movement of the wavefront sensor along the optical axis to change the distance between the spherical wave and the wavefront sensor. A double-sided reflector 5 is mounted on the top of the Shakhartmann wavefront sensor 4. The left side of the double-sided reflector 5 engages with a displacement sensor 9, which employs a high-precision linear displacement measurement device, enabling high-precision monitoring of displacement during spherical wave calibration. The right side of the double-sided reflector 5 is fitted with an autocollimator 6, which has high-precision angle measurement capabilities and can perform high-precision monitoring of rotation angles during plane wave calibration. The entire calibration experimental setup is stably mounted on the optical platform 1, which has good vibration isolation performance, reducing the impact of external vibrations on the calibration experiment and ensuring the accuracy and stability of the calibration experiment.

[0043] Combination Figure 4 As shown, in S120, the plane wave calibration theoretical model includes: Based on the theoretical model of plane wave calibration, the incident wavefront slope of the plane wave is precisely changed, and the position of the centroid of the photodetector spot will also move accordingly. By knowing the change in wavefront slope and the movement of the centroid of the spot, the distance between the microlens array and the camera target surface can be accurately calculated. because xy Consistency of direction, here taken as y Taking direction as an example, the two detections before and after precisely changing the slope can be represented as:

[0044] in, S It is the slope of the incident wavefront, Δ y The amount of movement of the light spot, f It is the distance between the lens array and the camera target surface; During the calibration process, the difference between the two wavefront slopes is precisely known:

[0045] Therefore, we get:

[0046] The distance between the microlens array and the camera target surface f The calculation formula is expressed as: .

[0047] Combination Figure 5 As shown, in S130, the spherical wave calibration theoretical model includes: Based on the spherical wave calibration theoretical model, the distance between the spherical wave and the Shack-Hartmann wavefront sensor is precisely changed, that is, the radius of curvature of the spherical wave is changed, thereby achieving a precise change in the slope of the wavefront to be measured. The position of the centroid of the light spot on the photodetector will also move accordingly. The size of the microlens unit is calibrated by the precisely known change in the distance between the spherical wave and the Shack-Hartmann wavefront sensor and the movement of the position of the centroid of the light spot. The calculation process uses the precisely calibrated distance between the microlens array and the camera target surface. Spherical wavefront representation

[0048] Based on the working principle of the Shaker-Hartmann wavefront sensor, namely the calculation relationship between the spot displacement and the wavefront slope, we obtain:

[0049] Where Δ is the displacement of the light spot's centroid.f It is the distance between the microlens array and the camera target surface. Z It is the distance between the spherical wave point light source and the Shackhartmann wavefront sensor, and is used as the radius of curvature of the spherical wave; When the incident light wave is a spherical wave, the distance between adjacent light spots on the photodetector is expressed as:

[0050] in, D It is the size of the microlens unit;

[0051]

[0052]

[0053] The size of the microlens unit D It can be obtained from the following formula: ; Among them, the change in the radius of curvature of the spherical wave Δ Z The distance between the Shackletmann wavefront sensor microlens array and the camera target surface f Microlens unit size D Distance between adjacent light spots Q The relationship between Δ Z , f and Q It is known.

[0054] Furthermore, during the calibration of the plane wave, the distance between the microlens array and the camera target surface obtained based on the plane wave calibration theoretical model includes: Plane wave-based calibration is performed to obtain the distance between the microlens array and the camera target surface. The off-axis parabolic collimator 8 is not equipped with a microscope objective 7 at its output port. The emitted parallel light is projected onto the Shakhartmann wavefront sensor 4 to be calibrated. The turntable 3 is controlled to rotate the Shakhartmann wavefront sensor 4, thereby changing the slope of the wavefront to be measured. Simultaneously, an autocollimator 6 is used for high-precision angle monitoring. The actual rotation angle is based on the autocollimator reading. By detecting the wavefront at two angular positions and combining this with the plane wave calibration theoretical model, the distance between the microlens array and the camera target surface is obtained. For example, at the initial position, the autocollimator reading is recorded as θ1. The initial position of the light spot centroid is then detected by the Shakhartmann wavefront sensor. Then, the turntable 3 is controlled to rotate a certain angle, changing the autocollimator reading to θ2. The new position of the light spot centroid is then detected again by the Shakhartmann wavefront sensor. By calculating the movement Δy of the centroid of the light spot during the two detections, and the known difference ΔS between the two wavefront slopes (ΔS=θ2-θ1, considering the relationship between the rotation angle of the turntable 3 and the wavefront slope, it can be approximately considered that the two are proportional within a small angle range), combined with the plane wave calibration theoretical model mentioned above, the distance f between the microlens array and the camera target surface can be accurately calculated.

[0055] Furthermore, during the calibration of spherical waves, the microlens unit size obtained based on the spherical wave calibration theoretical model includes: For spherical wave-based calibration, the microscope objective 7 is mounted at the exit port of the collimator. A spherical wave is projected onto the wavefront sensor. The distance between the wavefront sensor and the microscope objective 7 is changed by the translation mechanism 2, altering the radius of curvature of the wavefront to be calibrated. Simultaneously, a displacement sensor 9 is used for high-precision displacement monitoring. The actual displacement is based on the reading of the displacement sensor 9. By detecting the wavefront at two positions and combining this with the spherical wave calibration theoretical model, the size of the microlens unit is obtained. For example, at the initial position, the reading of the displacement sensor 9 is recorded as Z1. At this time, the distance Q1 between adjacent light spots on the photodetector is detected by the Shackleton-Hartmann wavefront sensor. Then, the wavefront sensor is moved a certain distance by the translation mechanism 2, changing the reading of the displacement sensor 9 to Z2. The distance Q2 between adjacent light spots is again detected by the Shackleton-Hartmann wavefront sensor. By calculating the change in the radius of curvature of the spherical wave ΔZ (ΔZ=|Z2-Z1|) during the two detections, and the known distance f between the microlens array and the camera target surface (obtained during the plane wave calibration process), the microlens unit size D can be obtained by combining it with the spherical wave calibration theoretical model mentioned above.

[0056] Combination Figure 6 As shown, correspondingly, this embodiment of the invention also provides a calibration device for the core parameters of a Shaker-Hartmann wavefront sensor, comprising: Unit 610 is established to pre-build a calibration experimental device based on the plane wave calibration theoretical model and the spherical wave calibration theoretical model.

[0057] The first calibration unit 620 is used to obtain the distance between the microlens array and the camera target surface based on the plane wave calibration theoretical model when calibrating a plane wave.

[0058] The second calibration unit 630 is used to obtain the microlens unit size based on the spherical wave calibration theoretical model when calibrating spherical waves.

[0059] Unit 610 is established based on the plane wave calibration theory model and the spherical wave calibration theory model. The calibration experimental device is built in advance according to the above-mentioned method for building the calibration experimental device.

[0060] During plane wave calibration, the first calibration unit 620 is activated. First, without a microscope objective mounted at the output port of the off-axis parabolic collimator, the emitted parallel light is projected onto the Shaker-Hartmann wavefront sensor to be calibrated. The turntable is rotated to change the slope of the wavefront to be measured, and an autocollimator performs high-precision angle monitoring. Through wavefront detection at two angular positions, combined with the plane wave calibration theoretical model, the first calibration unit 620 calculates the distance between the microlens array and the camera target surface.

[0061] During spherical wave calibration, the second calibration unit 630 is activated. A microscope objective is mounted at the exit port of the collimator, projecting a spherical wave onto the wavefront sensor. The distance between the wavefront sensor and the microscope objective is changed via a translation mechanism, and a displacement sensor performs high-precision displacement monitoring. Through wavefront detection at two locations, combined with the theoretical model of spherical wave calibration and the obtained distance between the microlens array and the camera target surface, the second calibration unit 630 calculates the microlens unit size.

[0062] Compared with the prior art, the present invention can achieve the following beneficial effects: This invention presents a calibration method and apparatus for the core parameters of a Shaker-Hartmann wavefront sensor. Through calibration based on the superposition of plane and spherical waves, it can obtain the distance between the microlens array and the camera target surface, and the size of the microlens units, which are strongly correlated with detection accuracy. The theoretical model possesses high accuracy. In the calibration scheme, simple and rapid switching between plane and spherical wave-based methods can be achieved by removing / adding microscope objectives, introducing very few error sources. The calibration scheme incorporates high-precision angle monitoring based on an autocollimator and high-precision displacement monitoring based on a displacement sensor, thereby ensuring high-precision calibration.

[0063] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for calibrating the core parameters of a Shaker-Hartmann wavefront sensor, characterized in that, include: A calibration experimental setup is pre-established based on the plane wave calibration theoretical model and the spherical wave calibration theoretical model; the pre-established calibration experimental setup includes: The calibration experimental device uses an off-axis parabolic collimator to provide plane waves, and an infinity imaging microscope objective is mounted on the off-axis parabolic collimator to provide spherical waves. The Shakhartmann wavefront sensor to be calibrated is mounted on a turntable, which is then mounted on a translation mechanism. A double-sided mirror is mounted on the top of the Shakhartmann wavefront sensor to be calibrated. The left side works with a displacement sensor to perform high-precision monitoring of displacement during spherical wave calibration, and the right side works with an autocollimator to perform high-precision monitoring of rotation angle during plane wave calibration. The calibration experimental device is stably mounted on an optical platform. The plane wave calibration theoretical model includes: Based on the theoretical model of plane wave calibration, the incident wavefront slope of the plane wave is precisely changed, and the position of the centroid of the photodetector spot will also move accordingly. By knowing the change in wavefront slope and the movement of the centroid of the spot, the distance between the microlens array and the camera target surface can be accurately calculated. because xy Consistency of direction, here taken as y Taking direction as an example, the two detections before and after precisely changing the slope can be represented as: in, S It is the slope of the incident wavefront, Δ y The amount of movement of the light spot, f It is the distance between the lens array and the camera target surface; During the calibration process, the difference between the two wavefront slopes is precisely known: Therefore, we get: The distance between the microlens array and the camera target surface f The calculation formula is expressed as: ； When calibrating a plane wave, the distance between the microlens array and the camera target surface is obtained based on the plane wave calibration theoretical model. When calibrating spherical waves, the microlens unit size is obtained based on the spherical wave calibration theoretical model.

2. The calibration method for the core parameters of the Shaker-Hartmann wavefront sensor according to claim 1, characterized in that, The theoretical model for spherical wave calibration includes: Based on the spherical wave calibration theoretical model, the distance between the spherical wave and the Shack-Hartmann wavefront sensor is precisely changed, that is, the radius of curvature of the spherical wave is changed, thereby achieving a precise change in the slope of the wavefront to be measured. The position of the centroid of the light spot on the photodetector will also move accordingly. The size of the microlens unit is calibrated by the precisely known change in the distance between the spherical wave and the Shack-Hartmann wavefront sensor and the movement of the position of the centroid of the light spot. The calculation process uses the precisely calibrated distance between the microlens array and the camera target surface. Spherical wavefront representation Based on the working principle of the Shaker-Hartmann wavefront sensor, namely the calculation relationship between the spot displacement and the wavefront slope, we obtain: Where Δ is the displacement of the light spot's centroid. f It is the distance between the microlens array and the camera target surface. Z It is the distance between the spherical wave point light source and the Shackhartmann wavefront sensor, and is used as the radius of curvature of the spherical wave; When the incident light wave is a spherical wave, the distance between adjacent light spots on the photodetector is expressed as: in, D It is the size of the microlens unit; The size of the microlens unit D It can be obtained from the following formula: ； Among them, the change in the radius of curvature of the spherical wave Δ Z The distance between the Shaker-Hartmann wavefront sensor microlens array and the camera target surface f Microlens unit size D Distance between adjacent light spots Q The relationship between Δ Z , f and Q It is known.

3. The calibration method for the core parameters of the Shaker-Hartmann wavefront sensor according to claim 2, characterized in that, When calibrating the plane wave, the distance between the microlens array and the camera target surface obtained based on the plane wave calibration theoretical model includes: A plane wave-based calibration is performed to obtain the distance between the microlens array and the camera target surface. No microscope objective is installed at the output port of the off-axis parabolic collimator. The emitted parallel light is then projected onto the Shaker-Hartmann wavefront sensor to be calibrated. A turntable is controlled to rotate the wavefront sensor, thereby changing the slope of the wavefront to be measured. Simultaneously, a high-precision rotation angle is monitored using an autocollimator. The actual rotation angle is based on the autocollimator reading. By detecting the wavefront at two angular positions and combining this with the plane wave calibration theoretical model, the distance between the microlens array and the camera target surface is obtained.

4. The calibration method for the core parameters of the Shaker-Hartmann wavefront sensor according to claim 3, characterized in that, When calibrating spherical waves, the microlens unit size obtained based on the spherical wave calibration theoretical model includes: To perform calibration based on spherical waves, the microscope objective is mounted at the light outlet of a collimator, and a spherical wave is projected onto the wavefront sensor. The distance between the wavefront sensor to be calibrated and the microscope objective is changed by a translation mechanism, thereby changing the radius of curvature of the wavefront to be measured. At the same time, a displacement sensor is used for high-precision displacement monitoring, and the actual displacement is based on the reading of the displacement sensor. By detecting the wavefront at two positions and combining it with the spherical wave calibration theoretical model, the size of the microlens unit is obtained.

5. A calibration device for the core parameters of a Shaker-Hartmann wavefront sensor, characterized in that, include: Establishment unit, used to pre-establish calibration experimental device based on plane wave calibration theoretical model and spherical wave calibration theoretical model; the pre-establishment of calibration experimental device based on plane wave calibration theoretical model and spherical wave calibration theoretical model includes: The calibration experimental device uses an off-axis parabolic collimator to provide plane waves, and an infinity imaging microscope objective is mounted on the off-axis parabolic collimator to provide spherical waves. The Shakhartmann wavefront sensor to be calibrated is mounted on a turntable, which is then mounted on a translation mechanism. A double-sided mirror is mounted on the top of the Shakhartmann wavefront sensor to be calibrated. The left side works with a displacement sensor to perform high-precision monitoring of displacement during spherical wave calibration, and the right side works with an autocollimator to perform high-precision monitoring of rotation angle during plane wave calibration. The calibration experimental device is stably mounted on an optical platform. The plane wave calibration theoretical model includes: Based on the theoretical model of plane wave calibration, the incident wavefront slope of the plane wave is precisely changed, and the position of the centroid of the photodetector spot will also move accordingly. By knowing the change in wavefront slope and the movement of the centroid of the spot, the distance between the microlens array and the camera target surface can be accurately calculated. because xy Consistency of direction, here taken as y Taking direction as an example, the two detections before and after precisely changing the slope can be represented as: in, S It is the slope of the incident wavefront, Δ y The amount of movement of the light spot, f It is the distance between the lens array and the camera target surface; During the calibration process, the difference between the two wavefront slopes is precisely known: Therefore, we get: The distance between the microlens array and the camera target surface f The calculation formula is expressed as: ； The first calibration unit is used to obtain the distance between the microlens array and the camera target surface based on the plane wave calibration theoretical model when calibrating the plane wave. The second calibration unit is used to obtain the microlens unit size based on the spherical wave calibration theoretical model when calibrating spherical waves.

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