Efficient differentiable optical system degradation simulation method

By using differential operators of point diffusion functions and gradient backpropagation methods in optical system degradation simulation, the problem of difficulty in applying micro-optical degradation simulation in the prior art is solved, and efficient and accurate simulation of small-diameter optical systems is achieved.

CN119596544AActive Publication Date: 2025-03-11ZHEJIANG UNIV
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Patent Information

Application Number
CN202411861071.0
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2024-12-17
Publication Date
2025-03-11
Estimated Expiration
2044-12-17

AI Technical Summary

Technical Problem

The prior art is difficult to effectively apply the differentiable degradable simulation of optical systems in mobile terminal modules, especially when it is limited by the diffraction effect, while the video memory space of the graphics computing card limits the problem that the calculation overhead cannot be too large.

Method used

A highly efficient and differentiable optical system degradation simulation method is proposed, which realizes image quality degradation simulation of optical system through differential operators of point diffusion function, and uses lower computing power overhead for gradient backpropagation, which is suitable for the combined optical number optimization task of general optical systems.

Benefits of technology

Accurate micro-optical degradation simulation of small-diameter, diffraction-constrained optical systems is realized, reducing memory overhead, and is suitable for optimization tasks of multiple point diffusion functions.

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Abstract

The invention discloses an efficient and differentiable optical system degradation simulation method. The method comprises the following steps: firstly, processing in computer optical simulation software to obtain an entrance pupil of an optical system, sampling according to the entrance pupil, then processing to obtain sampling grid points, and sequentially carrying out coherent complex amplitude and conjugate product processing according to the sampling grid points to obtain a point spread function; performing reverse gradient propagation according to the parameters in the point spread function to obtain an optimized gradient of the parameters in the point spread function; and finally performing degradation processing on the optical system according to the optimized gradient. According to the method, image quality degradation simulation of the optical system is accurately processed by using the point spread function, gradient back propagation is realized with relatively low computing power overhead, and the method is widely applied to a light number joint optimization task of a general optical system.
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Description

Technical Field

[0001] The invention belongs to the field of optical simulation, and in particular relates to an efficient and differentiable optical system degradation simulation method. Background Art

[0002] In recent years, computational optics has bridged the gap between optical design and downstream image post-processing algorithms, using a combination of software and hardware to find the optimal solution for image tasks, rather than just being restricted to the best optical imaging quality or the most suitable image post-processing algorithm. However, the differentiable degradation simulation of optical systems is currently limited to geometric aberrations, making it difficult to apply to mobile terminal modules that are limited by diffraction effects. Moreover, the video memory space of graphics computing cards limits the computational overhead of differentiable optical degradation simulation to a small amount. Therefore, new differentiable optical degradation simulation methods are urgently needed to solve this type of problem.

[0003] Existing simulation methods for differentiable optical degradation can be roughly summarized into two types: (1) Incoherent degradation simulation based on geometric aberration. It approximates the point spread function of the optical system as a light point diagram and renders the optical degradation by incoherent superposition. However, since it ignores the coherence between light rays and the diffraction effect of small-aperture systems, this type of method is only applicable to optical systems with limited geometric aberrations, and the analysis results for small-size, diffraction-limited systems have large deviations. (2) Coherent degradation simulation based on exit pupil diffraction. It performs diffraction calculations based on the optical path difference on the exit pupil plane, and can accurately model the degraded point spread function caused by the diffraction effect of the optical system. However, this method has a large memory overhead in the differentiable computing process and is difficult to apply to the optimization task of solving multiple point spread functions. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art and solve the problems existing in the background technology, the present invention proposes an efficient and differentiable optical system degradation simulation method. The present invention uses the differential operator of the point spread function to accurately realize the image quality degradation simulation of the optical system, and realizes gradient backpropagation with low computing power overhead. It is widely applicable to the light-number joint optimization tasks of general optical systems.

[0005] The technical solution adopted by the present invention is as follows:

[0006] An efficient and differentiable optical system degradation simulation method comprises the following steps:

[0007] S1. In computer optical simulation software, the optical surface, optical medium and object plane of the optical system are obtained, and the optical system is conjugated by the paraxial optical method according to the optical surface and optical medium of the optical system to obtain the entrance pupil of the optical system.

[0008] S2. Obtain the object point of the optical system according to the object plane, perform uniform sampling in the entrance pupil to obtain sampling points, emit light from the object point to the sampling point and perform surface tracing processing according to the optical surface to obtain a number of intersection points, and then perform centroid processing and grid point processing in turn according to the several intersection points to obtain a number of sampling grid points.

[0009] S3. Performing coherent complex amplitude processing on a plurality of sampling grid points to obtain coherent complex amplitude functions of the plurality of sampling grid points, and then performing conjugate product processing on the coherent complex amplitude functions to obtain point spread functions and parameters in the point spread functions.

[0010] S4. Perform forward propagation processing, gradient processing and loss function processing on the point spread function in sequence, and then use the automatic differentiation method to perform reverse gradient propagation on the point spread function to obtain the optimized gradient of the parameters in the point spread function.

[0011] S5. Degenerate the optical system according to the optimized gradient of the parameters in the point spread function to obtain a degraded optical system.

[0012] The step S2 is specifically as follows:

[0013] S21. Acquire an object point of the optical system according to the object plane, perform uniform sampling in the entrance pupil to obtain a plurality of sampling points, and emit light from the object point to each sampling point in the entrance pupil to obtain a plurality of sampling light rays.

[0014] S22. Obtain the light position, light direction and light wave number according to the sampled light, and use the light position, light direction and light wave number as storage data.

[0015] S23. Obtain the type of the next surface of the optical system according to the optical surface, perform ray tracing on the next surface, obtain a number of intersection points of the sampling light on the next surface, and obtain the optical path of each sampling light.

[0016] S24, repeating step S23 until all sampling light rays reach the last optical surface along the propagation direction, that is, reach the image plane, and obtain the intersection point of each sampling light ray on the image plane, that is, obtain a plurality of intersection points on the image plane.

[0017] S25, accumulating and summing all the optical paths of each sampling light to obtain the total optical path of each sampling light, that is, obtaining a plurality of optical paths of light.

[0018] S26, taking the centroids of the plurality of intersection points on the image plane to obtain the centroids of the plurality of intersection points on the image plane.

[0019] S27, taking the centroid on the image plane as the center and taking the preset pixel size of the image plane as the interval, a grid point process is established on the image plane to obtain a plurality of sampling grid points, and the sampling grid points are used as storage data.

[0020] The coherent complex amplitude function is set according to the following formula:

[0021]

[0022] Among them, U(x, y) is the complex amplitude function, e j Represents the phase factor of the complex number, i is the index, opd i represents the cumulative optical path of the i-th ray from the object point to the image plane, k represents the wave number, Δr i (x, y) represents the optical path difference from the sampling point (x, y) to the wavefront of the sampling light i in the point spread function, Represents the propagation direction vector of a single sampling ray and the image plane normal vector The inner product of It represents the complex amplitude of all sampled rays summed at the sampling point (x, y) in the point spread function.

[0023] The point spread function is set according to the following formula:

[0024]

[0025] Among them, PSF(x, y) is the point spread function, U(x, y) is the complex amplitude function, is the conjugate function of U(x, y)

[0026] The step S4 is specifically as follows:

[0027] S41, performing forward propagation processing on the point spread function, and constructing a differential operator based on the stored data.

[0028] S42. Performing gradient processing on the point spread function using an analytical differential relationship method according to the differential operator to obtain the gradient of the parameters in the point spread function.

[0029] S43, performing loss function processing on the point spread function to obtain the loss function of the point spread function.

[0030] S44. Perform reverse gradient propagation on the loss function of the point spread function using an automatic differentiation method to obtain an optimized gradient of the parameters in the point spread function.

[0031] The stored data in step S41 includes the light position, light direction, light path, light wave number and sampling grid points.

[0032] The gradient of the parameters in the point spread function in step S42 includes the gradient of the light position, the gradient of the light direction and the gradient of the light path.

[0033] The gradient of the light position is set according to the following formula:

[0034]

[0035] Among them, G o represents the gradient of the light position o, G PSF represents the gradient of the point spread function, PSF represents the point spread function, U represents the complex amplitude function, represents the derivative, o represents the position of the light, Re() and Im() represent the real and imaginary parts, is the phase of the complex amplitude function U.

[0036] The gradient of the light direction is set according to the following formula:

[0037]

[0038] Among them, d represents the direction of light, G d Represents the gradient of the light direction d, opd i represents the optical path length of the i-th ray, Δr i (x, y) represents the optical path difference from the i-th light ray to the grid point (x, y), e j represents the complex phase factor, k represents the wave number of the light, Indicates the normal direction of the image plane.

[0039] The gradient of the light path length is set according to the following formula:

[0040]

[0041] Among them, opd represents the optical path length of the light, G opd Represents the gradient of the light path length.

[0042] The beneficial effects of the present invention are:

[0043] The present invention is applied to the joint design task of computational optics. The accuracy of the simulation of the coherent point spread function based on plane wave characterization is better than that of the rendered incoherent point spread function under geometric aberration estimation, and is suitable for small-aperture, diffraction-limited optical systems. The differential operator of the point spread function uses an analytical formula to process the gradient in the return process, improves the problem of large video memory overhead of coherent degradation simulation, and realizes efficient differentiable optical degradation simulation. The present invention enables the optical-digital joint design task to accurately simulate optical degradation while meeting a large amount of video memory overhead. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic diagram of the overall process of the method of the present invention;

[0045] Figure 2This is a schematic diagram of ray tracing in Example 2 of the present invention;

[0046] Figure 3 It is a specific schematic diagram on the object surface in Example 2 of the present invention;

[0047] Figure 4 This is a specific schematic diagram on the image plane in Embodiment 2 of the present invention;

[0048] Figure 5 is a result diagram of the point spread function in Example 2 of the present invention;

[0049] Figure 6 This is the point spread function differential operator cost graph in embodiment 2 of the present invention. DETAILED DESCRIPTION

[0050] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0051] like Figure 1 As shown, embodiment 1 of the present invention includes the following steps:

[0052] S1. In computer optical simulation software, the optical surface, optical medium and object plane of the optical system are obtained, and the optical system is conjugated by the paraxial optical method according to the optical surface and optical medium of the optical system to obtain the entrance pupil of the optical system.

[0053] An optical surface is a surface on an optical element (such as a lens, a reflector, a prism, etc.) that is used to interact with light waves. The optical surface is defined according to the surface type and surface parameters of the optical system.

[0054] Optical media are materials through which light passes, including gases (including air), liquids and solids; they are defined according to the material names of optical systems.

[0055] The image plane is the last plane in the optical system where light rays are traced one by one, and it is also the plane where all light rays in the optical system converge to form a real image.

[0056] The conjugate processing is specifically to take the conjugate of the aperture in the object space, that is, to obtain the entrance pupil.

[0057] S2. Obtain the object point of the optical system according to the object plane, perform uniform sampling in the entrance pupil to obtain sampling points, emit light from the object point to the sampling point and perform surface tracing processing according to the optical surface to obtain a number of intersection points, and then perform centroid processing and grid point processing in turn according to the several intersection points to obtain a number of sampling grid points.

[0058] An object point is a point light source on the object surface.

[0059] The surface tracing process is to trace the light rays in the optical system in sequence according to the surface sequence until they reach the image plane.

[0060] Step S2 is specifically as follows:

[0061] S21. Acquire an object point of the optical system according to the object plane, perform uniform sampling in a rectangular grid in the entrance pupil to obtain a plurality of sampling points, and emit light from the object point to each sampling point in the entrance pupil to obtain a plurality of sampling light rays.

[0062] S22. Obtain the light position, light direction and light wave number according to the sampled light, and use the light position, light direction and light wave number as storage data.

[0063] S23. Obtain the type of the next surface of the optical system according to the optical surface, perform ray tracing on the next surface, obtain a number of intersection points of the sampling light on the next surface, and obtain the optical path of each sampling light.

[0064] S24, repeating step S23 until all sampling light rays reach the last optical surface along the propagation direction, that is, reach the image plane, and obtain the intersection point of each sampling light ray on the image plane, that is, obtain a plurality of intersection points on the image plane.

[0065] S25, accumulating and summing all the optical paths of each sampling light to obtain the total optical path of each sampling light, that is, obtaining a plurality of optical paths of light.

[0066] S26, taking the centroids of the plurality of intersection points on the image plane to obtain the centroids of the plurality of intersection points on the image plane.

[0067] S27, taking the centroid on the image plane as the center and taking the preset pixel size of the image plane as the interval, a grid point process is established on the image plane to obtain a plurality of sampling grid points, and the sampling grid points are used as storage data.

[0068] The sampling grid points are the coordinates of the pixel grid points on the image plane to be solved.

[0069] S3. Performing coherent complex amplitude processing on a plurality of sampling grid points to obtain coherent complex amplitude functions of the plurality of sampling grid points, and then performing conjugate product processing on the coherent complex amplitude functions of the plurality of sampling grid points to obtain a point spread function and parameters in the point spread function.

[0070] The coherent complex amplitude function is set according to the following formula:

[0071]

[0072] Among them, U(x, y) is the complex amplitude function, e j Represents the phase factor of the complex number, i is the index, opd i represents the cumulative optical path of the i-th ray from the object point to the image plane, k represents the wave number, Δr i(x, y) represents the optical path difference from the sampling point (x, y) to the wavefront of the sampling light i in the point spread function, Represents the propagation direction vector of a single sampling ray and the image plane normal vector The inner product of It represents the complex amplitude of all sampled rays summed at the sampling point (x, y) in the point spread function.

[0073] The point spread function is set as follows:

[0074]

[0075] Among them, PSF(x, y) is the point spread function, U(x, y) is the complex amplitude function, is the conjugate function of U(x, y)

[0076] S4. Perform forward propagation processing, gradient processing and loss function processing on the point spread function in sequence, and then use the automatic differentiation method to perform reverse gradient propagation on the point spread function to obtain the optimized gradient of the parameters in the point spread function.

[0077] Step S4 is specifically as follows:

[0078] S41, performing forward propagation processing on the point spread function, and constructing a differential operator based on the stored data.

[0079] The stored data in step S41 include the light position, light direction, light path length, light wave number and sampling grid points.

[0080] S42, performing gradient processing on the point spread function using an analytical differential relationship method according to a differential operator to obtain a gradient of a parameter in the point spread function;

[0081] The gradient of the parameters in the point spread function in step S42 includes the gradient of the light position, the gradient of the light direction and the gradient of the light path.

[0082] The gradient of the ray position is set by the following formula:

[0083]

[0084] Among them, G o represents the gradient of the light position o, G PSF represents the gradient of the point spread function, PSF represents the point spread function, U represents the complex amplitude function, represents the derivative, o represents the position of the light, Re() and Im() represent the real and imaginary parts, is the phase of the complex amplitude function U.

[0085] The gradient of the light direction is set according to the following formula:

[0086]

[0087] Among them, d represents the direction of light, G d Represents the gradient of the light direction d, opd i represents the optical path length of the i-th ray, Δr i (x, y) represents the optical path difference from the i-th light ray to the grid point (x, y), e j represents the complex phase factor, k represents the wave number of the light, Indicates the normal direction of the image plane.

[0088] The gradient of the light path length is set according to the following formula:

[0089]

[0090] Among them, opd represents the optical path length of the light, G opd Represents the gradient of the light path length.

[0091] S43, performing loss function processing on the point spread function to obtain a loss function of the point spread function;

[0092] S44. Perform reverse gradient propagation on the loss function of the point spread function using an automatic differentiation method to obtain an optimized gradient of the parameters in the point spread function.

[0093] S5. Degenerate the optical system according to the optimized gradient of the parameters in the point spread function to obtain a degraded optical system.

[0094] Degeneration processing is to optimize and update the parameters in the point spread function according to the optimized gradient of the parameters in the point spread function in order to reduce the dispersion degree of the point spread function and obtain a better quality optical system.

[0095] Example 2

[0096] D1. In computer optical simulation software, define the optical surface according to the surface type and surface parameters. The optical surfaces in this embodiment are all planes or spherical surfaces, including curvature, thickness and aperture parameters; and obtain the object surface in the computer optical simulation software.

[0097] D2. Define the optical medium between the surfaces according to the material name. In this embodiment, the materials S-LAH53, S-LAH52, and S-LAH51 are from the ORAHA material library, SF56A is from the SCHOTT material library, and FD11 is from the HOYA material library.

[0098] D3. According to the paraxial optical calculation, the conjugate of the system aperture in the object space, that is, the entrance pupil, is as follows: Figure 3 As shown, it is located 4.5116mm on the optical axis and has a diameter of 6.3468mm.

[0099] This embodiment defines the optical system by taking a double Gauss lens as shown in Table 1 as an example, wherein the operating wavelength is 587.6 nm, the system aperture is image space F / 1.2, and the aperture is 2.0123 mm;

[0100]

[0101] D3. Obtain the object point of the optical system according to the object plane. In this embodiment, starting from the object point of the 16.7° field of view, 129×129 sampling rays are uniformly arranged in a rectangular grid on the entrance pupil, such as Figure 3 shown.

[0102] D4. Tracing rays in sequence according to the surface sequence, first obtain the intersection of the sampling ray and the surface, and then process the emission direction after passing through the surface according to the law of refraction; Figure 2 As shown, the tracing process of some sampling rays is drawn.

[0103] D5. Trace all sampling light rays to the image plane to obtain several intersection points, take the centroid of several intersection points, and accumulate the optical path data of the sampling light during propagation, that is, the refractive index in the medium multiplied by the propagation distance.

[0104] D6, with the centroid on the image plane as the center and the preset sensor pixel size of 0.6um as the interval, define the sampling grid of the point spread function of 63×63 size, such as Figure 4 shown.

[0105] D7. In the forward calculation of the point spread function of the differential operator, the storage data (light position o, light direction d, light optical path opd, light wave number k, and point spread function sampling grid) are first stored, and then the coherent complex amplitude at the sampling point of the point spread function is processed according to the complex amplitude formula characterized by the plane wave:

[0106]

[0107] Among them, U(x, y) is the complex amplitude function, e j Represents the phase factor of the complex number, i is the index, opd i represents the cumulative optical path of the i-th ray from the object point to the image plane, k represents the wave number, Δr i (x, y) represents the optical path difference from the sampling point (x, y) to the wavefront of the sampling light i in the point spread function, Represents the propagation direction vector of a single sampling ray and the image plane normal vector The inner product of It represents the complex amplitude of all sampled rays summed at the sampling point (x, y) in the point spread function.

[0108] The point spread function is the complex amplitude function U(x, y) and its conjugate function The product, that is

[0109]

[0110] Among them, PSF(x, y) is the point spread function, U(x, y) is the complex amplitude function, is the conjugate function of U(x, y)

[0111] D8. In the back-propagation gradient process of the differential operator, the stored data in the forward process (light position o, light direction d, light path opd, light wave number k, and point spread function sampling grid) are first read out, and then the gradient of the light data is processed according to the analytical differential relationship.

[0112] The gradients of the parameters in the point spread function include the gradient of the light position, the gradient of the light direction, and the gradient of the light path.

[0113] The gradient of the light position o is set according to the following formula:

[0114]

[0115] Among them, G o represents the gradient of the light position o, G PSF represents the gradient of the point spread function, PSF represents the point spread function, U represents the complex amplitude function, represents the derivative, o represents the position of the light, Re() and Im() represent the real and imaginary parts, is the phase of the complex amplitude function U.

[0116] The gradient of the light direction d is set according to the following formula:

[0117]

[0118] Among them, d represents the direction of light, G d Represents the gradient of the light direction d, opd i represents the optical path length of the i-th ray, Δr i (x, y) represents the optical path difference from the i-th light ray to the grid point (x, y), e j represents the complex phase factor, k represents the wave number of the light, Indicates the normal direction of the image plane.

[0119] The gradient of the light path length opd is set according to the following formula:

[0120]

[0121] Among them, opd represents the optical path length of the light, G opd Represents the gradient of the light path length.

[0122] Figure 5 The forward calculation results of the point spread function differential operator are compared with the reference processing results output in the Zemax optical simulation software, which illustrates the accuracy of the method of the present invention in simulating optical degradation. Figure 6 This is a memory overhead curve required for processing multiple point spread functions. The point spread function differential operator saves 18.4 times the memory overhead compared to the automatic differentiation function writing method, which shows the high efficiency of the method of the present invention.

[0123] D9, the loss function Loss for processing the point spread function. In this example, we set it to the maximum value of the point spread function.

[0124] D10. Use Pytorch's automatic differentiation tool for reverse gradient propagation.

[0125] D11. Obtain the optimized gradient of the parameters in the point spread function. The optimized variable in this example is set to the curvature of surface 1 to surface 6.

[0126] D12. Degenerate the optical system according to the optimized gradient of the parameters in the point spread function to obtain a degraded optical system.

[0127] Table 2 shows the gradient output results in this example, and compares them with the gradient reference calculated by the finite element method. The relative error is less than one thousandth, which shows the accuracy of the method of the present invention in differential calculation and can be applied to the optical-numerical joint optimization design task.

[0128]

[0129]

[0130] The efficient and differentiable optical system degradation simulation method proposed in the present invention realizes accurate differentiable optical degradation coherent simulation through the differential operator of the point spread function. At the same time, the differential operator of the point spread function proposed in the present invention uses an analytical formula to process gradient information, improves the problem of large video memory overhead of coherent degradation simulation, and realizes efficient and differentiable optical degradation simulation.

Claims

1. An efficient and differentiable optical system degradation simulation method, characterized by: The following steps are involved: S1. In computer optical simulation software, the optical surface, optical medium and object plane of the optical system are obtained, and the optical system is conjugated by using the paraxial optical method according to the optical surface and optical medium of the optical system to obtain the entrance pupil of the optical system; S2, acquiring an object point of the optical system according to the object plane, uniformly sampling in the entrance pupil to obtain sampling points, emitting light from the object point to the sampling point and performing surface-by-surface tracing processing according to the optical surface to obtain a number of intersection points, and then performing centroid processing and grid point processing in sequence according to the number of intersection points to obtain a number of sampling grid points; S3, performing coherent complex amplitude processing according to a number of sampling grid points to obtain coherent complex amplitude functions of the number of sampling grid points, and then performing conjugate product processing on the coherent complex amplitude function to obtain a point spread function and parameters in the point spread function; S4, performing forward propagation processing, gradient processing and loss function processing on the point spread function in sequence, and then using the automatic differentiation method to perform reverse gradient propagation on the point spread function to obtain the optimized gradient of the parameters in the point spread function; S5. Degenerate the optical system according to the optimized gradient of the parameters in the point spread function to obtain a degraded optical system.

2. The efficient and differentiable optical system degradation simulation method according to claim 1, characterized in that: The step S2 is specifically as follows: S21, acquiring an object point of the optical system according to the object plane, performing uniform sampling in the entrance pupil to obtain a plurality of sampling points, and emitting light from the object point to each sampling point in the entrance pupil to obtain a plurality of sampling light rays; S22, obtaining the light position, light direction and light wave number according to the sampled light, and using the light position, light direction and light wave number as storage data; S23, obtaining the type of the next surface of the optical system according to the optical surface, performing ray tracing on the next surface, obtaining a number of intersection points of the sampling light on the next surface, and obtaining the optical path of each sampling light; S24, repeating step S23 until all sampling light rays reach the last optical surface along the propagation direction, that is, reach the image plane, and obtain the intersection point of each sampling light ray on the image plane, that is, obtain a plurality of intersection points on the image plane; S25, performing cumulative sum processing on all the optical paths of each sampling light to obtain the total optical path of each sampling light, that is, obtaining the optical paths of several light rays; S26, taking the centroid of the plurality of intersection points on the image plane to obtain the centroid of the plurality of intersection points on the image plane; S27, taking the centroid on the image plane as the center and taking the preset pixel size of the image plane as the interval, a grid point process is established on the image plane to obtain a plurality of sampling grid points, and the sampling grid points are used as storage data.

3. The efficient and differentiable optical system degradation simulation method according to claim 1, characterized in that: The coherent complex amplitude function is set according to the following formula: Among them, U(x, y) is the complex amplitude function, e j Represents the phase factor of the complex number, i is the index, opd i represents the cumulative optical path of the i-th ray from the object point to the image plane, k represents the wave number, Δr i (x, y) represents the optical path difference from the sampling point (x, y) to the wavefront of the sampling light i in the point spread function, Represents the propagation direction vector of a single sampling ray and the image plane normal vector The inner product of It represents the complex amplitude of all sampled rays summed at the sampling point (x, y) in the point spread function.

4. The efficient and differentiable optical system degradation simulation method according to claim 1, characterized in that: The point spread function is set according to the following formula: Among them, PSF(x, y) is the point spread function, U(x, y) is the complex amplitude function, is the conjugate function of U(x, y) 5. The efficient and differentiable optical system degradation simulation method according to claim 1, characterized in that: The step S4 is specifically as follows: S41, performing forward propagation processing on the point spread function, and constructing a differential operator according to the stored data; S42, performing gradient processing on the point spread function using an analytical differential relationship method according to the differential operator to obtain the gradient of the parameters in the point spread function; S43, performing loss function processing on the point spread function to obtain a loss function of the point spread function; S44. Perform reverse gradient propagation on the loss function of the point spread function using an automatic differentiation method to obtain an optimized gradient of the parameters in the point spread function.

6. The efficient and differentiable optical system degradation simulation method according to claim 5, characterized in that: The stored data in step S41 includes the light position, light direction, light path, light wave number and sampling grid points.

7. The efficient and differentiable optical system degradation simulation method according to claim 5, characterized in that: The gradient of the parameters in the point spread function in step S42 includes the gradient of the light position, the gradient of the light direction and the gradient of the light path.

8. The efficient and differentiable optical system degradation simulation method according to claim 7, characterized in that: The gradient of the light position is set according to the following formula: Among them, G o represents the gradient of the light position o, G PSF represents the gradient of the point spread function, PSF represents the point spread function, U represents the complex amplitude function, represents the derivative, o represents the position of the light, Re() and Im() represent the real and imaginary parts, is the phase of the complex amplitude function U.

9. The efficient and differentiable optical system degradation simulation method according to claim 7, characterized in that: The gradient of the light direction is set according to the following formula: Among them, d represents the direction of light, G d Represents the gradient of the light direction d, opd i represents the optical path length of the i-th ray, Δr i (x, y) represents the optical path difference from the i-th light ray to the grid point (x, y), e j represents the complex phase factor, k represents the wave number of the light, Indicates the normal direction of the image plane.

10. The efficient and differentiable optical system degradation simulation method according to claim 7, characterized in that: The gradient of the light path length is set according to the following formula: Among them, opd represents the optical path length of the light, G opd Represents the gradient of the light path length.

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