Wavefront joint quantitative distribution analysis and image quality evaluation method and device for triple-mirror zoom system

Abstract

The present invention provides a method and device for combined quantitative distribution analysis of wavefronts and image quality assessment of a three-mirror zoom system. The method comprises: obtaining aberration changes caused by changes in pupil position during zooming based on the relationship between primary aberration coefficients and diaphragm position, and evaluating the optimal diaphragm position of the three-mirror zoom system based on the aberration changes; fitting the wavefront shape of the exit pupil in the three-mirror zoom system using Zernike polynomials, and evaluating the oscillation of the wavefront shape based on the fitting results; analyzing the pupil wavefront before and after the diaphragm position change, calculating the pupil wavefront deformation caused by the diaphragm movement, and achieving full-focal-range image quality assessment of the three-mirror zoom system. The present invention can analyze the exit pupil wavefront shape and the aberration coefficients and wavefront changes caused by pupil changes for a three-mirror zoom system with variable focal length at all focal lengths, providing a theoretical basis for subsequent directional optimization design of optical systems.

Description

Technical Field

[0001] The present invention relates to the field of optoelectronic imaging technology, and in particular to a wavefront joint quantitative distribution analysis and image quality evaluation method and device for a three-mirror zoom system. Background Art

[0002] With the rapid development of imaging technology in recent years, users have increasingly demanded higher quality images generated by optical imaging systems. The dual demands for wide field of view and high definition at telephoto zoom have increased the complexity of imaging systems, requiring them to meet complex aberration functions at multiple focal lengths and maintain stable image quality as focal lengths change.

[0003] The development of space optical systems has evolved from refractive to reflective systems. Due to limitations in lens materials, refractive systems face challenges such as limited aperture, difficulty correcting chromatic aberration, and difficulty in lightweighting. Reflective materials are easy to process, easily upscaled, lightweight, and heat-resistant. After coating, they exhibit high reflectivity across a wide wavelength range, and total reflection systems exhibit no chromatic aberration. The design of an off-axis three-mirror optical system is based on Gaussian optical theory, using a coaxial three-mirror optical system as the initial structure. Adjustments to the surface shape and spacing of the three mirrors are employed to eliminate aberrations such as spherical aberration, coma, and astigmatism.

[0004] Traditional image quality assessment methods primarily use optical design software to evaluate the system's image quality parameters. However, for a three-mirror zoom system, this evaluation method cannot correlate the changes in system imaging quality at various focal lengths, making it difficult to provide an accurate basis for subsequent optimization design of the system. Summary of the Invention

[0005] In view of this, the present invention provides a method and apparatus for wavefront joint quantitative distribution analysis and image quality evaluation of a three-mirror zoom system to solve at least one of the above-mentioned problems.

[0006] In order to achieve the above object, the present invention adopts the following scheme:

[0007] According to a first aspect of the present invention, a method for joint quantitative distribution analysis of wavefronts and image quality evaluation of a three-mirror zoom system is provided, the method comprising: obtaining aberration changes caused by changes in pupil position during zooming based on the relationship between primary aberration coefficients and aperture positions, and evaluating the optimal aperture position of the three-mirror zoom system based on the aberration changes; fitting the wavefront shape of the exit pupil in the three-mirror zoom system using Zernike polynomials, and evaluating the oscillation of the wavefront shape based on the fitting results; analyzing the pupil wavefront before and after the aperture position change, calculating the wavefront deformation at the pupil caused by the aperture movement, and realizing full-focal-range image quality evaluation of the three-mirror zoom system.

[0008] As an embodiment of the present invention, the method of obtaining aberration changes caused by changes in pupil position during zooming based on the relationship between primary aberration coefficients and aperture positions, and evaluating the optimal aperture position of the three-mirror zoom system based on the aberration changes, includes: establishing a three-mirror zoom system based on a Gaussian bracket method and a system magnification relationship; setting an initial aperture position, adjusting the aperture position to analyze the impact of aperture position changes on the aberration coefficients of the three-mirror zoom system when the system is zoomed, and evaluating the aberrations of the three-mirror zoom system at the new aperture position; analyzing the aperture position for correcting the system aberrations at all focal lengths based on the changes in the aberration coefficients of the three-mirror zoom system caused by the aperture position changes; and introducing an optimization function to analyze the aberration changes at various positions across the entire focal length when the aperture position changes, to obtain the optimal aperture position for the three-mirror zoom system.

[0009] As an embodiment of the present invention, the above method uses Zernike polynomials to fit the wavefront shape of the exit pupil in the three-mirror zoom system, and evaluates the oscillation of the wavefront shape based on the fitting results, including: using Zernike polynomials to fit the wavefront shape of the exit pupil in the three-mirror zoom system to obtain a wavefront expression; based on the wavefront expression obtained by fitting, analyzing the fluctuations of the wavefront shape to obtain the change of the wavefront at the full focal length of the three-mirror zoom system relative to the reference wavefront.

[0010] As an embodiment of the present invention, the above-mentioned method analyzes pupil wavefronts before and after changes in the aperture position, calculates the wavefront deformation at the pupil caused by the aperture movement, and implements image quality evaluation of the three-mirror zoom system at all focal lengths, including: combining the image quality analysis of the aperture position change with the wavefront change at the exit pupil of the three-mirror zoom system to obtain the deformation of the wavefront as light propagates in free space with changes in the aperture position; based on the analysis of the wavefront deformation as the aperture position changes, calculates the change in the wave aberration coefficient as the aperture position moves; and evaluates and analyzes the wavefront shape as the aperture position moves to obtain image quality analysis of the three-mirror zoom system as the pupil position changes at different focal lengths.

[0011] According to a second aspect of the present invention, a wavefront joint quantitative distribution analysis and image quality evaluation device for a three-mirror zoom system is provided, the device comprising: a first evaluation unit, for obtaining aberration changes caused by changes in pupil position during zooming based on the relationship between primary aberration coefficients and aperture positions, and evaluating the optimal aperture position of the three-mirror zoom system based on the aberration changes; a second evaluation unit, for fitting the wavefront shape of the exit pupil in the three-mirror zoom system using Zernike polynomials, and evaluating the oscillation of the wavefront shape based on the fitting results; and a comprehensive evaluation unit, for analyzing the pupil wavefront before and after the aperture position change, calculating the wavefront deformation at the pupil caused by the aperture movement, and realizing full-focal-range image quality evaluation of the three-mirror zoom system.

[0012] As one embodiment of the present invention, the first evaluation unit includes: a system establishment module for establishing a three-mirror zoom system based on a Gaussian bracket method and a system zoom relationship; an aberration evaluation module for setting an initial aperture position, adjusting the aperture position to analyze the effect of aperture position changes on the aberration coefficients of the three-mirror zoom system when the system zooms, and evaluating the aberrations of the three-mirror zoom system at the new aperture position; an aperture position analysis module for analyzing the aperture position for correcting system aberrations at all focal lengths based on changes in the aberration coefficients of the three-mirror zoom system caused by the aperture position changes; and an optimal aperture position acquisition module for introducing an optimization function to analyze the aberration changes at various positions across the entire focal length when the aperture position changes, thereby obtaining the optimal aperture position for the three-mirror zoom system.

[0013] As an embodiment of the present invention, the above-mentioned second evaluation unit includes: a fitting module, which is used to use Zernike polynomials to fit the wavefront shape of the exit pupil in the three-mirror zoom system to obtain a wavefront expression; and a wavefront shape analysis module, which is used to analyze the changes in the wavefront shape based on the wavefront expression obtained by fitting, and obtain the change status of the wavefront at the full focal length of the three-mirror zoom system relative to the reference wavefront.

[0014] As an embodiment of the present invention, the above-mentioned comprehensive evaluation unit includes: a wavefront deformation acquisition module, which is used to combine the image quality analysis of the aperture position change with the wavefront change at the exit pupil of the three-mirror zoom system to obtain the deformation of the wavefront as the aperture position changes when the light propagates in free space; an aperture change acquisition module, which is used to provide the change of the wave aberration coefficient as the aperture position moves based on the analysis of the wavefront deformation as the aperture position changes; and an image quality analysis module, which is used to evaluate and analyze the wavefront shape as the aperture position moves to obtain the image quality analysis of the three-mirror zoom system when the pupil position changes at different focal lengths.

[0015] According to a third aspect of the present invention, there is provided an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-described method when executing the computer program. According to a fourth aspect, there is provided a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the above-described method when executed by the processor.

[0016] It can be seen from the above technical solution that the wavefront joint quantitative distribution analysis and image quality evaluation method and device of the three-mirror zoom system provided by the present invention can realize the wavefront shape analysis at the exit pupil of the three-mirror zoom system with variable focal length at all focal lengths and the analysis of the aberration coefficient and wavefront change caused by the pupil change, providing a theoretical basis for the subsequent directional optimization design of the optical system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0018] Figure 1 1 is a flow chart of a method for wavefront joint quantitative distribution analysis and image quality evaluation of a three-mirror zoom system provided by an embodiment of the present invention;

[0019] Figure 2 is a schematic diagram of a process for obtaining an optimal aperture position provided by an embodiment of the present application;

[0020] Figure 3 This is a structural diagram of a short-focus position system using a three-mirror zoom structure provided in an embodiment of the present application;

[0021] Figure 4 This is a structural diagram of a telephoto position system using a three-mirror zoom structure provided by an embodiment of the present application;

[0022] Figure 5 Schematic diagram of a process for evaluating the oscillation of a wavefront shape provided in an embodiment of the present application;

[0023] Figure 6 This is a schematic diagram of a process for performing full-focal-range image quality evaluation provided by an embodiment of the present application;

[0024] Figure 7 This is a wavefront shape diagram at the exit pupil of a certain focal length when the optical system is located at the original aperture position, provided by an embodiment of the present application;

[0025] Figure 8 This is a diagram of the wavefront shape at the exit pupil when the aperture position of the optical system changes and the wavefront fluctuates, as provided in an embodiment of the present application;

[0026] Figure 9 1 is a schematic structural diagram of a device for wavefront joint quantitative distribution analysis and image quality evaluation of a three-mirror zoom system provided by an embodiment of the present invention;

[0027] Figure 10 is a structural diagram of a first evaluation unit provided in an embodiment of the present invention;

[0028] Figure 11 is a structural diagram of a second evaluation unit provided by an embodiment of the present invention;

[0029] Figure 12 is a schematic structural diagram of a comprehensive evaluation unit provided by an embodiment of the present invention;

[0030] Figure 13 This is a schematic block diagram of the system structure of the electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] To make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings. Here, the exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0032] As mentioned earlier, traditional image quality evaluation methods mainly use optical design software to evaluate the system's image quality parameters. However, for zoom systems, this evaluation method cannot link the changes in system imaging quality at various focal lengths, making it difficult to provide an accurate basis for subsequent optimization design.

[0033] Therefore, it is necessary to further evaluate the wavefront shape of the zoom system, especially the need to evaluate the wavefront changes under the full field of view and full focal length, so as to provide feedback for the optimization design iteration of the zoom system, realize the optimization of specific areas of the zoom system, and ultimately realize the directional imaging quality improvement design process of the entire zoom system. In addition, for the zoom system, the position of the aperture in the zoom system has an important influence on the imaging quality of the zoom system. During the zoom process of the system, the pupil position changes with the change of the focal length and field of view of the zoom system, and exhibits different aberration characteristics. The appropriate aperture position can effectively eliminate the coma, astigmatism or distortion of the system. In order to achieve stable imaging of the zoom system within the full focal length range and smooth exit pupil wavefront, it is necessary to evaluate the specific changes in aberrations and wavefronts caused by changes in pupil position.

[0034] Based on the above reasons, the present invention proposes a wavefront joint quantitative distribution analysis and image quality evaluation method and device for a three-mirror zoom system, which can realize the analysis of the wavefront shape at the exit pupil of the three-mirror zoom system at all focal lengths and the analysis of the aberration coefficient and wavefront change caused by pupil change.

[0035] like Figure 1 FIG. 1 is a flow chart of a method for wavefront joint quantitative distribution analysis and image quality evaluation of a three-mirror zoom system provided by an embodiment of the present invention. The method includes the following steps:

[0036] Step S101: obtaining aberration changes caused by pupil position changes during zooming based on a relationship between a primary aberration coefficient and an aperture position, and evaluating an optimal aperture position of the three-mirror zoom system according to the aberration changes.

[0037] Step S102: fitting the wavefront shape of the exit pupil in the three-mirror zoom system using Zernike polynomials, and evaluating the oscillation of the wavefront shape based on the fitting result.

[0038] Step S103: Analyze the pupil wavefront before and after the aperture position changes, calculate the pupil wavefront deformation caused by the aperture movement, and evaluate the full-focal-range image quality of the three-mirror zoom system.

[0039] It can be seen from the above technical solution that the wavefront joint quantitative distribution analysis and image quality evaluation method of the three-mirror zoom system provided by the present invention can realize the wavefront shape analysis at the exit pupil of the three-mirror zoom system with variable focal length at all focal lengths and the analysis of the aberration coefficient and wavefront change caused by the pupil change, providing a theoretical basis for the subsequent directional optimization design of the optical system.

[0040] Preferably, Figure 2 As shown, the above step S101 may further include the following sub-steps:

[0041] Step S1011: establishing a three-mirror zoom system according to the Gaussian bracket method and the system zoom relationship.

[0042] The Gaussian bracket method is a mathematical method used to analyze light propagation in optical systems. It helps designers understand and optimize the performance of optical systems by using matrices to describe the propagation characteristics of light in optical components.

[0043] In this step, the Gauss bracket method is used to establish the fixed zoom equation of the three-mirror zoom system as follows:

[0044] Z= 1 A m+1 =[φ1,-d1,φ2-d2,...,φ m ,d m ]= 1 A3=[φ1,-d1,φ2,-d2,φ3,-d3];

[0045] In the above formula, Z represents the zoom equation parameter of the fixed zoom system. 1 A m+1 The Gaussian bracket method parameter characterizing the number of system components is m+1, 1 A3 represents the parameters of the fixed zoom equation of the three-mirror structure, φ1, φ2, ..., φ m Characterize the optical power of the i=1, 2, 3, ..., m components, d1, d2, ..., d m Characterizes the intervals between i=1, 2, 3, ..., m components.

[0046] The expression for the equivalent optical power Φ of the fixed zoom system expressed by the Gaussian constant is as follows:

[0047] Φ= 1 C m =[φ1,-d1,φ2,-d2,....,φ m ]=1 C3=[φ1,-d1,φ2,-d2,φ3]

[0048] In the above formula, 1 C m Characterizing the system components is the m Gaussian bracket method parameter, in this embodiment, 1 C3 characterizes the parameters of the fixed zoom equation of the three-mirror structure.

[0049] Furthermore, the schematic diagram of the three-mirror zoom system at short and long focal lengths obtained based on the Gaussian bracket method and the system zoom relationship can be shown as follows: Figure 3 and Figure 4 shown.

[0050] Step S1012: setting an initial aperture position, adjusting the aperture position to analyze the effect of aperture position change on the aberration coefficient of the three-mirror zoom system when the system zooms, and evaluating the aberration of the three-mirror zoom system at the new aperture position.

[0051] Set any original position as the initial aperture position. When the aperture position changes, the primary aberration coefficient of the new aperture position can be directly calculated based on the primary aberration coefficient of the original aperture position. After the aperture position moves, the ray tracing process follows the following law:

[0052]

[0053] In the above formula, i,u,h are the angle between the first paraxial ray and the normal, the aperture angle and the incident height; i z ,u z ,h z are the angle between the second paraxial ray and the normal, the aperture angle, and the incident height. Parameters marked with an * represent the optical parameters of the new system after the aperture position is moved. K is a parameter that characterizes the position of the new aperture relative to the original aperture, and is used as a reference for aperture position movement in the present invention.

[0054] Based on this, the primary aberration coefficient at the new aperture position is obtained, which is expressed by the primary aberration coefficient of the system at the original aperture position:

[0055]

[0056] where ΣS I ,∑S II ,∑S III ,∑S IV ,∑S V They represent Seidel spherical aberration, coma, astigmatism, field curvature, and distortion respectively. The parameters marked with "*" represent the optical parameters of the new system after the aperture position is moved. From this, the relationship between the aperture position and the primary aberration coefficient of the three-mirror zoom system is obtained.

[0057] Based on the relationship between the aperture position and the primary aberration coefficient of the three-mirror zoom system, the change in the aberration coefficient when the aperture position changes can be calculated and evaluated, and then the appropriate aperture position can be selected according to the aberration indicators of the system design.

[0058] Step S1013: Analyze the diaphragm position for correcting the system aberration at the full focal length according to the change in the aberration coefficient of the three-mirror zoom system caused by the change in the diaphragm position.

[0059] According to the relationship between the aperture position and the primary aberration coefficients of the three-mirror zoom system in step S1012, it is found that, in addition to the system spherical aberration and field curvature, the coma, astigmatism, and distortion of the new system after the aperture position is changed can all be represented by the aperture position parameter K and the system primary aberration coefficients at the original aperture position. Thus, the aperture position parameter K at which the system coma, astigmatism, and distortion are respectively zero after the aperture position is moved can be calculated, as follows:

[0060] When the system is coma-free, the aperture position parameter K satisfies:

[0061]

[0062] Based on this, the position of the coma-eliminating aperture at each focal length can be solved respectively.

[0063] When the system is free of astigmatism, the aperture position parameter K satisfies:

[0064]

[0065] Based on this, the position of the anastigmatism aperture at each focal length can be solved respectively.

[0066] When the system is dedistorted, the aperture position satisfies:

[0067] K 3 ∑S I +3K 2 ∑S II +K(3∑S III +∑S IV )+∑S V =0;

[0068] Based on this, the position of the distortion-eliminating aperture at each focal length can be solved respectively.

[0069] By comparing the current aperture position parameter K with the aperture position parameter K when the system eliminates coma, astigmatism and distortion, the difference can be used to evaluate the coma, astigmatism and distortion conditions of the three-mirror zoom system at the current aperture position. The larger the difference, the worse the coma, astigmatism and distortion performance of the system at this aperture position; the smaller the difference, the better the coma, astigmatism and distortion performance of the system at this aperture position; This shows that the system has good coma, astigmatism and distortion performance at this aperture position, among which The aperture position parameter used to eliminate coma, astigmatism or distortion, ε is the parameter index.

[0070] Step S1014: introducing an optimization function to analyze the aberration changes at each position of the full focal length when the aperture position changes, and obtaining the optimal aperture position of the three-mirror zoom system.

[0071] When the aperture position changes, the system's coma, astigmatism, and distortion coefficients also change differently at different focal lengths. For the entire three-mirror zoom system, the aperture position for eliminating coma, astigmatism, and distortion varies at different focal lengths. To achieve good performance of all aberrations across the entire system's focal lengths, an optimization objective function can be set based on the above analysis. The optimization objective function designed in this embodiment is as follows:

[0072]

[0073] The optimal aperture position K of the system at the full focal length can be calculated through the above optimization objective function, where w i (i=1,2,3...) are weight coefficients, and F1, F2, and F3 represent the coma, astigmatism, and distortion objective functions of the system at all focal lengths, respectively. This application has now completed the image quality analysis of the system based on the change in aperture position.

[0074] Preferably, Figure 5 As shown, the above step S102 may further include the following sub-steps:

[0075] Step S1021: Using Zernike polynomials to fit the wavefront shape of the exit pupil in the three-mirror zoom system, a wavefront expression is obtained.

[0076] The wavefront function is a mathematical function used to describe the phase distribution of the wavefront in space. It provides a quantitative way to represent the shape of the wavefront. Therefore, this step can fit the wavefront function at the exit pupil. The wavefront function can be represented by a high-order Zernike polynomial according to Taylor expansion as follows:

[0077]

[0078] Where Z i (ρ,θ) is a Zernike polynomial, q i are the Zernike polynomial coefficients, and the waveform function at the system exit pupil wavefront can be obtained by using an appropriate fitting basis.

[0079] The wavefront function at the exit pupil of the three-mirror zoom system in this embodiment is fitted using high-order Zernike polynomials at the short focal length, long focal length, and full field of view, respectively. The subscripts W and T are used to represent the short focal length and long focal length, respectively, and j represents different fields of view. It can be represented as follows:

[0080]

[0081] Step S1022: analyzing the fluctuation of the wavefront shape according to the wavefront expression obtained by fitting, and obtaining the change of the wavefront relative to the reference wavefront at the full focal length of the three-mirror zoom system.

[0082] Based on the fitted wavefront expression, the peak and trough values ​​(PV values) and the mean square value (RMS value) of the wavefront can be analyzed and evaluated, and used as key indicators for evaluating the system's wavefront flatness and imaging stability. When the wavefront shape at the exit pupil of the three-mirror zoom system meets the following indicators, the three-mirror zoom system is considered to have good imaging quality and a relatively smooth wavefront:

[0083] PV<ξ,RMS<τ;

[0084] Here, ξ and τ are indicators related to the design requirements of the three-mirror zoom system, which can be set according to different requirements for the system's imaging quality. This completes the evaluation of the oscillation of the wavefront shape at the exit pupil of the three-mirror zoom system.

[0085] Preferably, Figure 6 As shown, the above step S103 may further include the following sub-steps:

[0086] Step S1031: combining the image quality analysis of the change in the aperture position with the wavefront change at the exit pupil of the three-mirror zoom system, to obtain the deformation of the wavefront as the aperture position changes when the light propagates in free space.

[0087] The wavefront after the aperture position of the three-mirror zoom system is moved is analyzed, such as Figure 7 and Figure 8 As shown in the figure, when the aperture changes (the aperture position changes from the second element to the first element), the wavefront at the exit pupil also changes. In order to achieve a smooth wavefront and a better aberration coefficient, it is necessary to analyze the wavefront shape after the aperture position changes. The system wavefront change after the aperture position changes can be expressed by the following formula:

[0088]

[0089] In the above formula, Indicates that the wavefront shape changes with the aperture position, K is the aperture position parameter, ж=nu z y-nuy z is the Lagrange invariant of the system, is the gradient function of the wave aberration with respect to the system aperture.

[0090] This can be used to express the wavefront function after the system aperture moves:

[0091]

[0092] Based on the above calculations and the wavefront functions for the full field of view and full focal length obtained in steps S1021 and S1022, the changes in the system wavefront aberration when the aperture position moves to any position over the full field of view and full focal length of the three-mirror zoom system can be obtained. The PV and RMS evaluation methods in step S1022 are still used to analyze the smoothness of the wavefront at the exit pupil after the change.

[0093] Step S1032: Based on the analysis of the deformation of the wavefront as the aperture position changes, the change of the wavefront aberration coefficient as the aperture position moves is given.

[0094] In this embodiment, based on the wavefront function of the three-mirror zoom system after the diaphragm is moved, the numerical relationship between the moving wavefront aberration and the change in the diaphragm position can be obtained. Taking the fourth-order wavefront aberration of the three-mirror zoom system as an example:

[0095]

[0096] Therefore, based on the system wave aberration expression after the aperture position is changed, the various aberration coefficients and imaging quality of the three-mirror zoom system after adjusting the aperture can be further evaluated.

[0097] Step S1033: Evaluate and analyze the wavefront shape of the aperture position movement to obtain image quality analysis of the three-mirror zoom system when the pupil position changes at different focal lengths.

[0098] This step analyzes the pupil position of the three-mirror zoom system in this embodiment after zooming at various focal lengths, such as short focus and long focus. Based on the wavefront oscillation and wavefront aberration coefficient changes caused by the aperture position changes introduced in steps S1031 and S1032, and in accordance with the system design index requirements of this embodiment, a comparative analysis is performed with the various wavefront aberration coefficients to achieve a more comprehensive evaluation of the system's imaging quality.

[0099] As can be seen from the above, the present invention analyzes the changes in system aberrations caused by changes in the aperture position during zooming by introducing the relationship between the aperture position and the aberration coefficient. Furthermore, the present invention also introduces a Zernike fitting polynomial to fit the wavefront shape of the system exit pupil, and evaluates the overall image quality of the system by analyzing the oscillation of the wavefront shape. Finally, based on the changes in the aperture position and the system wavefront, the wavefront deformation of the system caused by the aperture is analyzed and calculated, providing a theoretical basis for the subsequent directional optimization design of the three-mirror zoom system.

[0100] like Figure 9FIG2 is a schematic diagram of the structure of a wavefront joint quantitative distribution analysis and image quality evaluation device for a three-mirror zoom system provided by an embodiment of the present application. The device includes: a first evaluation unit 910, a second evaluation unit 920, and a comprehensive evaluation unit 930, which are sequentially connected.

[0101] The first evaluation unit 910 is configured to obtain an aberration change caused by a change in pupil position during zooming based on a relationship between a primary aberration coefficient and an aperture position, and to evaluate an optimal aperture position of the three-mirror zoom system according to the aberration change.

[0102] The second evaluation unit 920 is configured to fit the wavefront shape of the exit pupil in the three-mirror zoom system using Zernike polynomials, and evaluate the oscillation of the wavefront shape based on the fitting result.

[0103] The comprehensive evaluation unit 930 is used to analyze the pupil wavefront before and after the aperture position changes, calculate the pupil wavefront deformation caused by the aperture movement, and realize the full-focal-range image quality evaluation of the three-mirror zoom system.

[0104] Preferably, Figure 10 As shown, the first evaluation unit 910 may further include:

[0105] The system establishment module 911 is used to establish a three-mirror zoom system according to the Gauss bracket method and the system zoom relationship.

[0106] The aberration evaluation module 912 is used to set the initial aperture position, adjust the aperture position to analyze the impact of the aperture position change on the aberration coefficient of the three-mirror zoom system when the system zooms, and evaluate the aberration of the three-mirror zoom system at the new aperture position.

[0107] The iris position analysis module 913 is used to analyze the iris position for correcting the system aberration at all focal lengths based on the change in the aberration coefficient of the three-mirror zoom system caused by the change in the iris position.

[0108] The optimal aperture position acquisition module 914 is used to introduce an optimization function to analyze the aberration changes at each position of the full focal length when the aperture position changes, and obtain the optimal aperture position of the three-mirror zoom system.

[0109] Preferably, Figure 11 As shown, the second evaluation unit 920 may further include:

[0110] The fitting module 921 is used to fit the wavefront shape of the exit pupil in the three-mirror zoom system using Zernike polynomials to obtain a wavefront expression.

[0111] The wavefront shape analysis module 922 is used to analyze the fluctuation of the wavefront shape according to the wavefront expression obtained by fitting, and obtain the change of the wavefront at the full focal length of the three-mirror zoom system relative to the reference wavefront.

[0112] Preferably, Figure 12 As shown, the comprehensive evaluation unit 930 may further include:

[0113] The wavefront deformation acquisition module 931 is used to combine the image quality analysis of the aperture position change with the wavefront change at the exit pupil of the three-mirror zoom system to obtain the deformation of the wavefront caused by the change of the aperture position when the light propagates in free space.

[0114] The aperture change acquisition module 932 is used to provide the change of the wavefront aberration coefficient as the aperture position moves based on the analysis of the deformation of the wavefront as the aperture position changes.

[0115] The image quality analysis module 933 is used to evaluate and analyze the wavefront shape of the aperture position movement to obtain image quality analysis of the three-mirror zoom system when the pupil position changes at different focal lengths.

[0116] The detailed description of the above-mentioned units and modules can be found in the corresponding description in the aforementioned method embodiment, which will not be repeated here.

[0117] As can be seen from the above technical solution, the wavefront joint quantitative distribution analysis and image quality evaluation device provided by the present invention for the three-mirror zoom system can realize the analysis of the wavefront shape at the exit pupil of the three-mirror zoom system at all focal lengths, as well as the analysis of the aberration coefficient and wavefront change caused by the pupil change, providing a theoretical basis for the subsequent directional optimization design of the optical system. Specifically, by introducing the relationship between the aperture position and the aberration coefficient, the present invention analyzes the system aberration change caused by the change of the aperture position when the focal length is changed; in addition, the Zernike fitting polynomial is introduced to fit the wavefront shape of the system exit pupil, and the overall image quality of the system is evaluated by analyzing the oscillation of the wavefront shape; finally, based on the change of the aperture position and the change of the system wavefront, the wavefront deformation of the system caused by the aperture is analyzed and calculated, providing a theoretical basis for the subsequent directional optimization design of the three-mirror zoom system.

[0118] An embodiment of the present invention further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the above method is implemented when the processor executes the program.

[0119] An embodiment of the present invention further provides a computer-readable storage medium storing a computer program for executing the above method.

[0120] like Figure 13As shown, the electronic device 600 may further include: a communication module 110, an input unit 120, an audio processor 130, a display 160, and a power supply 170. It is worth noting that the electronic device 600 does not necessarily have to include Figure 13 In addition, the electronic device 600 may also include all components shown in Figure 13 For components not shown, reference may be made to the prior art.

[0121] like Figure 13 As shown, the central processing unit 100 is sometimes also referred to as a controller or an operation control unit, and may include a microprocessor or other processor device and / or logic device. The central processing unit 100 receives inputs and controls the operations of various components of the electronic device 600 .

[0122] Memory 140 may be, for example, one or more of a cache, flash memory, hard drive, removable media, volatile memory, non-volatile memory, or other suitable devices. It may store the aforementioned failure-related information and may also store programs that execute the relevant information. The CPU 100 may execute the programs stored in memory 140 to implement information storage or processing.

[0123] The input unit 120 provides input to the CPU 100. The input unit 120 may be, for example, a keypad or touch input device. The power supply 170 is used to provide power to the electronic device 600. The display 160 is used to display objects such as images and text. The display may be, for example, an LCD display, but is not limited thereto.

[0124] The memory 140 may be a solid-state memory, such as a read-only memory (ROM), a random access memory (RAM), or a SIM card. Alternatively, it may be a memory that retains information even when power is off, can be selectively erased, and is provided with more data. Examples of such memory are sometimes referred to as EPROMs. The memory 140 may also be some other type of device. The memory 140 includes a buffer memory 141 (sometimes referred to as a buffer). The memory 140 may include an application / function storage unit 142 for storing application programs and function programs or processes for executing the operations of the electronic device 600 via the central processing unit 100.

[0125] The memory 140 may also include a data storage unit 143 for storing data, such as contacts, digital data, pictures, sounds, and / or any other data used by the electronic device. The driver storage unit 144 of the memory 140 may include various driver programs for communication functions of the electronic device and / or for executing other functions of the electronic device (such as messaging applications, address book applications, etc.).

[0126] The communication module 110 is a transmitter / receiver that transmits and receives signals via the antenna 111. The communication module 110 (transmitter / receiver) is coupled to the central processor 100 to provide input signals and receive output signals, which may be the same as the case of a conventional mobile communication terminal.

[0127] Based on different communication technologies, multiple communication modules 110 may be provided in the same electronic device, such as a cellular network module, a Bluetooth module, and / or a wireless local area network module. The communication module 110 (transmitter / receiver) is also coupled to a speaker 131 and a microphone 132 via an audio processor 130 to provide audio output via the speaker 131 and receive audio input from the microphone 132, thereby implementing common telecommunication functions. The audio processor 130 may include any suitable buffer, decoder, amplifier, etc. Furthermore, the audio processor 130 is coupled to the central processing unit 100, enabling local recording via the microphone 132 and playback of stored audio via the speaker 131.

[0128] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0129] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0130] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0131] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0132] Specific embodiments are used in the present invention to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A wavefront joint quantitative distribution analysis and image quality evaluation method for a three-mirror zoom system, characterized by: The method comprises: Obtaining aberration changes caused by changes in pupil position during zooming based on a relationship between a primary aberration coefficient and an aperture position, and evaluating an optimal aperture position for the three-mirror zoom system based on the aberration changes; Fitting the wavefront shape of the exit pupil in the three-mirror zoom system using Zernike polynomials, and evaluating the oscillation of the wavefront shape based on the fitting result; Analyze the pupil wavefront before and after the aperture position changes, calculate the pupil wavefront deformation caused by the aperture movement, and realize the full-focal-range image quality evaluation of the three-mirror zoom system; The method of obtaining an aberration change caused by a change in pupil position during zooming based on a relationship between a primary aberration coefficient and an aperture position, and evaluating an optimal aperture position of the three-mirror zoom system according to the aberration change includes: The three-mirror zoom system is established based on the Gauss bracket method and the system magnification relationship; The initial aperture position was set and the aperture position was adjusted to analyze the effect of the aperture position change on the aberration coefficient of the three-mirror zoom system when the system zooms, and the aberration of the three-mirror zoom system at the new aperture position was evaluated; Based on the changes in the aberration coefficient of the three-mirror zoom system caused by the change in the aperture position, the aperture position for correcting the system aberration at all focal lengths is analyzed; An optimization function is introduced to analyze the aberration changes at each position of the full focal length when the aperture position changes, and the optimal aperture position of the three-mirror zoom system is obtained. The analysis of pupil wavefronts before and after the aperture position changes, calculation of pupil wavefront deformation caused by the aperture movement, and evaluation of the full-focal-range image quality of the three-mirror zoom system include: By combining the image quality analysis of the change of the aperture position with the wavefront change at the exit pupil of the three-mirror zoom system, the deformation of the wavefront caused by the change of the aperture position when the light propagates in free space is obtained. Based on the analysis of the wavefront deformation with the change of the aperture position, the changes of the aberration coefficient with the movement of the aperture position are given; The wavefront shape of the moving aperture position is evaluated and analyzed to obtain the image quality analysis of the three-mirror zoom system when the pupil position changes at different focal lengths.

2. The wavefront joint quantitative distribution analysis and image quality evaluation method for a three-mirror zoom system according to claim 1, wherein: The step of fitting the wavefront shape of the exit pupil of the three-mirror zoom system by using Zernike polynomials and evaluating the oscillation of the wavefront shape based on the fitting result includes: The wavefront shape of the exit pupil in the three-mirror zoom system is fitted using Zernike polynomials to obtain the wavefront expression. According to the wavefront expression obtained by fitting, the fluctuation of the wavefront shape is analyzed to obtain the change of the wavefront relative to the reference wavefront at the full focal length of the three-mirror zoom system.

3. A wavefront joint quantitative distribution analysis and image quality evaluation device for a three-mirror zoom system, characterized in that: The device comprises: a first evaluation unit configured to obtain an aberration change caused by a change in pupil position during zooming based on a relationship between a primary aberration coefficient and an aperture position, and to evaluate an optimal aperture position of the three-mirror zoom system according to the aberration change; a second evaluation unit, configured to fit a wavefront shape of an exit pupil in the three-mirror zoom system using Zernike polynomials, and evaluate an oscillation of the wavefront shape based on the fitting result; Comprehensive evaluation unit, used to analyze pupil wavefront before and after the aperture position changes, calculate the pupil wavefront deformation caused by the aperture movement, and realize the full-focal-range image quality evaluation of the three-mirror zoom system; The first evaluation unit includes: System establishment module, used to establish a three-mirror zoom system based on the Gauss bracket method and system magnification relationship; An aberration evaluation module is used to set the initial aperture position, adjust the aperture position to analyze the impact of the aperture position change on the aberration coefficient of the three-mirror zoom system when the system zooms, and evaluate the aberration of the three-mirror zoom system at the new aperture position; An aperture position analysis module is used to analyze the aperture position for correcting system aberrations at all focal lengths based on changes in the aberration coefficients of the three-mirror zoom system caused by changes in the aperture position; The optimal aperture position acquisition module is used to introduce an optimization function to analyze the aberration changes at each position of the full focal length when the aperture position changes, and obtain the optimal aperture position of the three-mirror zoom system; The comprehensive assessment unit includes: The wavefront deformation acquisition module is used to combine the image quality analysis of the aperture position change with the wavefront change at the exit pupil of the three-mirror zoom system to obtain the deformation of the wavefront that occurs when the aperture position changes when the light propagates in free space; The aperture change acquisition module is used to provide the change of the aberration coefficient as the aperture position moves based on the analysis of the deformation of the wavefront as the aperture position changes; The image quality analysis module is used to evaluate and analyze the wavefront shape of the aperture position movement, and obtain the image quality analysis of the three-mirror zoom system when the pupil position changes at different focal lengths.

4. The wavefront joint quantitative distribution analysis and image quality evaluation device for a three-mirror zoom system according to claim 3, wherein: The second evaluation unit includes: The fitting module is used to fit the wavefront shape of the exit pupil in the three-mirror zoom system using Zernike polynomials to obtain a wavefront expression.

5. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 2 are implemented.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 2 are implemented.

Images