Multi-closed-loop and multi-objective optimization method for space optical imaging system based on system propagation function

Abstract

The present invention relates to the field of space optical imaging technology, and in particular to a multi-closed-loop multi-objective optimization method for a space optical imaging system based on a system transfer function. The optical system is sequentially subjected to optical design optimization, structural design optimization and temperature design optimization. During the optimization process of the design stage, the system transfer function is used as the optimization target to obtain a global optimal design result. After all design optimizations are completed, an approximate functional relationship is established between the design variables and the system transfer function in each design stage by using experimental design and approximate fitting model methods, and the design variables are adjusted by using sensitivity analysis results to complete the closed loop of the overall optimization process, that is, to realize the multi-closed-loop optimization process within the design stage and the overall system.

Description

Technical Field

[0001] The present invention belongs to the technical field of space optical imaging, and in particular relates to a multi-closed-loop multi-objective optimization method for a space optical imaging system based on a system transfer function. Background Art

[0002] The optimization design of space optical imaging system is divided into three stages: optical design, structural design and temperature control design. The goal of optical design is to optimize the system modulation transfer function (MTF, referred to as system transfer function) and to make the tolerance as wide as possible; the goal of structural design is to meet the dynamic / static requirements of the system and to reduce the total weight as much as possible; the goal of temperature control design is to make the system temperature uniform and the total heating power as low as possible. Among these design goals, optical tolerance requirements, total structural weight and total temperature control heating power are also design variables. Therefore, multi-objective optimization design is required for space optical imaging system.

[0003] Typical optimization design process of space optical imaging system is as follows: Figure 1 As shown in Figure 1, the overall optimization process is an open-loop process and can only be closed-loop optimized within the design phase. The optimization target within each design phase is not the final evaluation index of the system, so the optimization result of each design phase can only achieve local optimality. Summary of the invention

[0004] In view of this, the present invention aims to provide a multi-closed-loop and multi-objective optimization method for a space optical imaging system based on a system transfer function, in which the system transfer function is used as the optimization target in the optimization process of each design stage, and a global optimal design result is obtained in each design stage; an approximate functional relationship is established between the design variables and the system transfer function in each design stage by utilizing experimental design and approximate fitting model methods, and the design variables are adjusted according to the results of sensitivity analysis to complete the closed loop of the overall optimization process, that is, to realize a multi-closed-loop optimization process within the design stage and the overall system.

[0005] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0006] A multi-closed-loop multi-objective optimization method for a space optical imaging system based on a system transfer function comprises the following steps:

[0007] S1: With the goal of achieving the best system transfer function and the widest tolerance range of the optical system, the optical system is optimized and the parameters are designed to obtain the optimal optical surface and the best position of each reflector in the optical system;

[0008] S2: setting the optimal optical surface and the optimal position obtained in step S1 in the optical system, and performing structural optimization design on the current optical system;

[0009] S3: Performing temperature optimization design on the optical system obtained in step S2;

[0010] S4: repeat steps S1 to S3 N times to obtain N optimization parameters, and respectively calculate the system transfer functions corresponding to the N optimization parameters; construct an approximate fitting model according to the N optimization parameters and the N system transfer functions; determine the optimal parameter of each optimization parameter according to the approximate fitting model through a sensitivity analysis method;

[0011] S5: Calculate the corresponding system transfer function according to the optimal parameters obtained in step S4; if the current system transfer function meets the target transfer function requirements, output the optimal parameters at this time; if the current system transfer function does not meet the target transfer function requirements, repeat steps S1 to S5 until the current system transfer function meets the target transfer function requirements.

[0012] Furthermore, the structural optimization design in step S2 includes:

[0013] S21: Perform mechanical calculations on the current optical system;

[0014] S22: Calculate the position change and surface error of each reflector in the current optical system;

[0015] S23: Obtaining the system transfer function of the current optical system according to the mechanical calculation result obtained in step S21 and the position change and surface error of each reflector calculated in step S22;

[0016] S24: Adjust the optimization parameters in the current optical system, and repeat steps S21 to S23 until the system transfer function of the current optical system reaches the optimum under the mechanical environment conditions and the total weight of the current optical system is the lowest.

[0017] Furthermore, in the temperature optimization design in step S3, the power of each heating zone in the optical system obtained in step S2 is adjusted so that the system transfer function of the optical system after adjusting the power of each heating zone is optimal and the total power of the heating zones of the optical system is the lowest at this time.

[0018] Furthermore, in step S4, a structural finite element analysis is performed on each optimization parameter to obtain the position changes of each node on the optical surface of each reflector in the optical system corresponding to each optimization parameter; the position changes of each node on the optical surface are fitted to obtain the wave aberration, angular displacement and linear displacement of the optical surface; and the system transfer function corresponding to each optimization parameter is calculated based on the wave aberration, angular displacement and linear displacement of the optical surface.

[0019] Furthermore, in step S5, when the current system transmission code is greater than or equal to the target transmission code, the target transmission code requirement is met.

[0020] Compared with the prior art, the invention can achieve the following beneficial effects:

[0021] In the multi-closed-loop multi-objective optimization method for a space optical imaging system based on a system transfer function created by the present invention, multiple optimization objectives of the space optical imaging system in the optical, structural and temperature control design stages are reduced to system transfer functions, and an approximate fitting model between multiple design variables and the system transfer functions in the optical, structural and temperature control design stages is established by using an experimental design and an approximate fitting model method; a sensitivity analysis method is used to achieve optimal adjustment of the design variables, to form a multi-closed-loop optimization process within the overall hierarchy and design stage, to achieve global optimization, and to solve the problem that the existing method can only perform closed-loop optimization within the design stage, resulting in the optimization results of each design stage only being able to achieve local optimization; in the process of processing and assembly, only the optimal parameters need to be determined through the approximate fitting model and the target transfer function, thereby guiding the optical processing and assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0023] Figure 1 Schematic diagram of the process flow for optimizing the design of a typical space optical imaging system;

[0024] Figure 2 A schematic diagram of a flow chart of a multi-closed-loop multi-objective optimization method for a space optical imaging system based on a system transfer function according to an embodiment of the present invention;

[0025] Figure 3 A flowchart of a multi-closed-loop multi-objective optimization method for a space optical imaging system based on a system transfer function according to an embodiment of the present invention;

[0026] Figure 4 A schematic diagram of the optical path structure of the optical system after the optical optimization design described in the embodiment of the present invention;

[0027] Figure 5 A system transfer function curve corresponding to the optical system after the optical optimization design described in the embodiment of the present invention;

[0028] Figure 6 A schematic diagram of the result of the structural optimization design described in the embodiment of the present invention;

[0029] Figure 7 A schematic diagram of temperature distribution of an optical system under low temperature conditions after temperature control optimization design according to an embodiment of the present invention;

[0030] Figure 8 A schematic diagram of temperature distribution of an optical system under high temperature conditions after temperature control optimization design according to an embodiment of the present invention;

[0031] Fig. 9 Provide a flowchart for the implementation of integrated optimization software;

[0032] Fig.10 It is the contour relationship diagram between the system transfer function and the reflector position tolerance allocation;

[0033] Fig.11 The global sensitivity analysis result diagram of each reflector position tolerance;

[0034] Fig.12 It is the system transfer function curve of the final optical system under the gravity condition in the Y direction;

[0035] Fig.13 It is the system transfer function curve of the final optical system under the gravity condition in the Z direction;

[0036] Fig.14 This is the system transfer function curve of the final optical system under the condition of a temperature rise of 4°C.

[0037] Description of reference numerals:

[0038] 1. Primary mirror; 2. Secondary mirror; 3. Tertiary mirror; 4. Optical system support structure. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the invention more clear, the invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described here are only used to explain the invention and do not constitute a limitation of the invention.

[0040] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0041] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0042] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0043] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0044] like Figure 2 and Figure 3 As shown, the multi-closed-loop multi-objective optimization method for a space optical imaging system based on a system transfer function described in an embodiment of the present invention comprises the following steps:

[0045] S1: With the goal of achieving the best system transfer function and the widest tolerance range of the optical system, the optical system parameters are optimized to obtain the optimal optical surface and the best position of each reflector in the optical system.

[0046] S2: The optimal optical surface and the optimal position obtained in step S1 are set in the optical system, and the structural optimization design of the current optical system is performed. The structural optimization design in step S2 includes:

[0047] S21: Perform mechanical calculations on the current optical system;

[0048] S22: Calculate the position change (including the rigid body displacement and rotation angle of the reflector) and the surface error of each reflector in the current optical system;

[0049] S23: Obtaining the system transfer function of the current optical system according to the mechanical calculation result obtained in step S21 and the position change and surface error of each reflector calculated in step S22;

[0050] S24: Adjust the optimization parameters in the current optical system, and repeat steps S21 to S23 until the system transfer function of the current optical system reaches the optimum under the mechanical environment conditions and the total weight of the current optical system is the lowest.

[0051] S3: Perform temperature optimization design on the optical system obtained in step S2. Since the various parts of the optical system will expand and contract under different temperatures, which will cause the optical system to change to varying degrees, such as the reflector will change its surface shape after expansion and contraction, and the optical system frame will deform. Therefore, after adjusting the power of each heating zone in the optical system obtained in step S2, the optical system changes, and the system transfer function of the optical system after adjusting the power of each heating zone is optimized. At the same time, it is also necessary to ensure that the total power of the heating zone of the optical system is the lowest at this time.

[0052] S4: Use the experimental design method (DOE) to design the experiment for the optimization parameters and obtain a sufficient number of sample points, that is, repeat steps S1 to S3 N times to obtain N optimization parameters, and calculate the system transfer functions corresponding to the N optimization parameters respectively. The specific process is: perform structural finite element analysis on each optimization parameter to obtain the position changes of each node on the optical surface of each reflector in the optical system corresponding to each optimization parameter; fit the position changes of each node on the optical surface to obtain the wave aberration, angular displacement and linear displacement of the optical surface; calculate the system transfer function corresponding to each optimization parameter based on the wave aberration, angular displacement and linear displacement of the optical surface.

[0053] According to N optimization parameters and N system transfer functions, an approximate fitting model between the optimization parameters and the system transfer function is constructed to obtain the functional relationship between the optimization parameters and the system transfer function. The fitting error of the approximate fitting model should be less than 5%. Through the sensitivity analysis method, the optimal parameter of each optimization parameter is determined according to the approximate fitting model to achieve system-level closed-loop optimization.

[0054] S5: Calculate the corresponding system transfer function according to the optimal parameters obtained in step S4; if the current system transfer function meets the target transfer function requirements, output the optimal parameters at this time; if the current system transfer function does not meet the target transfer function requirements, repeat steps S1 to S5 until the current system transfer function meets the target transfer function requirements. The target transfer function requirements are set and adjusted accordingly according to the design requirements and actual conditions of the optical system, that is, if the current system transfer function is greater than or equal to the target transfer function, the target transfer function requirements are met.

[0055] In order to clearly illustrate the multi-closed-loop and multi-objective optimization method of the space optical imaging system based on the system transfer function described in the embodiment of the present invention, the present invention is further described in detail by taking the optimization of the position tolerance distribution of each reflector of a large field of view off-axis TMA camera as an example (that is, the optical system is a large field of view off-axis TMA camera, and the optimization parameter is the position tolerance distribution of the reflector). Specific embodiment:

[0057] S1: Perform optical optimization design, that is, take the optimal system transfer function and the widest tolerance range of the optical system as the goal, design the optimization parameters of the optical system, and obtain the optimal optical surface and the best position of each reflector in the optical system. In this specific example, the optical optimization design is performed by CODE V optical design software, that is, CODE V optical design software is used to complete the allocation of reflector position tolerances of the designed optical system and calculate the system transfer function of the current optical system. The optical optimization design results are shown in Figure 4 As shown, the lines of different colors represent the light of different fields of view (0 field of view, ±0.7 field of view and ±1 field of view) in the optical system. The system transfer function curve corresponding to the optical system after optical optimization design is as follows Figure 5 As shown, Figure 5 The curves of each color line in Figure 4 The linear rays of different colors correspond to each other, which means they represent rays of different fields of view. Figure 5 The black line in the middle represents the diffraction limit of the optical system, and the colored lines represent different fields of view in the optical system. As can be seen from Figure 5, the transfer function of each field of view of the system is close to the diffraction limit, indicating that the calculated transfer function of the optical system is good and meets the design requirements.

[0058] S2: The optimal optical surface and the optimal position obtained in step S1 are set in the optical system, and the structural optimization design of the current optical system is performed. In this specific embodiment, the structural optimization design in step S2 includes:

[0059] S21: Use the structural simulation software Patran / Nastran to perform mechanical calculations on the current optical system under various working conditions;

[0060] S22: Using the optical fitting software Sigfit to obtain the position change and surface shape error of each reflector;

[0061] S23: inputting the mechanical calculation result obtained in step S21 and the position change and surface error of each reflector obtained in step S22 into the optical design software CODE V to obtain the system transfer function of the current optical system;

[0062] S24: Adjust the tolerance distribution of the reflector position in the current optical system, and repeat steps S21 to S23 until the system transfer function of the current optical system reaches the optimum under the mechanical environment conditions and the total weight of the current optical system is the lowest.

[0063] The structural optimization design results of step S2 are as follows: Figure 6As shown, the primary mirror 1, the secondary mirror 2 and the tertiary mirror 3 are supported by the optical system support structure 4 and together form the core optical-mechanical structure of the large-field off-axis TMA camera. The system transfer function results of the design results under various working conditions (including the current optical system working conditions under Y-axis gravity, Z-axis gravity and 4°C temperature rise) are shown in Table 1. In Table 1, PV (Peak to Valley) represents the peak-to-valley value of the mirror surface, which is a common indicator of the surface quality of the optical surface, RMS represents the surface error of the mirror surface, Tx, Ty and Tz represent the linear displacement of the mirror moving along the x-axis, y-axis and z-axis of the spatial coordinate system, respectively, and Rx, Ry and Rz represent the angular displacement of the mirror rotating along the x-axis, y-axis and z-axis of the spatial coordinate system, respectively.

[0064] Table 1:

[0065]

[0066] In some specific embodiments, the structural optimization design can also be performed by a topology optimization method, and the process is as follows: first, define the design space and conditions, that is, determine the design space, boundary conditions, loading conditions and objective function (such as maximizing stiffness, minimizing weight, etc.) of the optical system structure, where the design space refers to the material area available during the optimization process; then, set the objective function and constraints, that is, select the optimization goal (such as minimizing material usage or maximizing structural stiffness) and constraints (such as stress constraints, displacement constraints or material volume constraints), which will guide the topology optimization algorithm to find a suitable structural layout; discretize the design space, that is, divide the design space into finite element grid units, and each unit can be assigned a different material density. The density value is usually between 0 and 1, where 0 means no material and 1 means full material. Iterative solution is performed, that is, the material distribution of each grid unit is iteratively updated using a topology optimization algorithm (such as the density method, SIMP method, or level set method), and the unit density is adjusted according to the objective function and constraints by solving the response of the structure under loading conditions. Material removal and distribution optimization: According to the optimization algorithm, unnecessary materials are removed and the materials are concentrated in key positions that need to be loaded. This process is repeated continuously so that the material gradually approaches the optimal structural shape. Convergence judgment, that is, when the objective function (such as structural stiffness or weight) reaches the convergence condition, or the number of iterations reaches the set value, the optimization process ends. Finally, result analysis and post-processing are performed, that is, the material distribution results obtained by topology optimization are post-processed to generate an optimized structural design. Usually, this optimization result also needs shape optimization and size optimization to further improve performance and adapt to manufacturing requirements.

[0067] Table 2:

[0068]

[0069] S3: Perform temperature optimization design on the optical system obtained in step S2. Adjust the power of each heating zone in the optical system obtained in step S2 so that the system transfer function of the optical system after adjusting the power of each heating zone is optimal, and the total power of the heating zone of the optical system is the lowest. In this specific embodiment, TMG thermal analysis software is used to calculate the temperature distribution of the optical system under low or high temperature conditions after adjusting the power of each heating zone. In the embodiment of the present invention, the range of high and low temperatures is 20±4°C, and the temperature distribution is as follows: Figure 7 and Figure 8 As shown, Figure 7 and Figure 8 Different colors in the color bar on the right side of the figure represent different temperatures. The system transfer functions calculated under the two working conditions are shown in Table 2. The rigid body displacement in Table 2 is the linear displacement in Table 1, and the rotation angle in Table 2 is the angular displacement in Table 1.

[0070] S4: Repeat steps S1-S3 N times to obtain N reflector position tolerance allocations, and respectively calculate the system transfer functions corresponding to the N reflector position tolerance allocations. In this specific embodiment, N is 500-1000, that is, repeat steps S1-S3 500-1000 times to obtain 500-1000 reflector position tolerance allocations, and respectively calculate the system transfer functions corresponding to 500-1000 reflector position tolerance allocations.

[0071] The following operations are performed in the integrated optimization software to obtain the system transfer function corresponding to the position tolerance allocation of each reflector: First, the position tolerance allocation of each reflector is used as a design variable and input into the finite element model of the optomechanical structure, and then a simulation analysis is performed in the finite element analysis software Nastran. Through the structural finite element analysis, the displacement results of each node on the optical surface are obtained, and the displacement results of each node on the optical surface represent the movement of each node under the influence of load or environment; then, the optical surface node displacement results obtained in Nastran are imported into the optical surface fitting tool Sigfit to perform the fitting calculation of the optical surface. Sigfit can process these displacement data and output two main results: wave aberration, angular displacement and linear displacement; among them, wave aberration represents the error of the optical surface, and angular displacement and linear displacement represent the position change of the optical surface (such as rotation and displacement); finally, the wave aberration, angular displacement and linear displacement obtained in Sigfit will be written into the optical design input file and imported into the optical design software CODE V for calculation. CODE V software calculates the system transfer function of the current optical system (that is, the imaging quality of the current optical system) based on these input data, that is, the system transfer function corresponding to the position tolerance allocation of each reflector is obtained. The above implementation process is as follows: Fig. 9As shown. The reflector position tolerance allocation is changed many times and the corresponding system transfer function is calculated to obtain multiple sets of data. The response surface method in the integrated optimization software is used to establish an approximate fitting model based on the multiple sets of data. The sensitivity analysis method in the integrated optimization software is used to obtain the optimal reflector position tolerance allocation. Fig.10 As shown in the figure, under the Z-axis gravity condition, the relationship between the X-axis translation of the primary mirror and the X-axis translation of the three mirrors demonstrates the sensitivity of the system transfer function to the tolerance distribution of the mirror position, which helps to optimize the tolerance distribution of the mirror position. Fig.11 The global sensitivity of each reflector position tolerance is shown. The horizontal axis shows the sensitivity percentage of the reflector position tolerance. The larger the value, the greater the influence of the reflector position change on the system transfer function. Fig.11 The meanings of the parameters on the middle vertical axis and the corresponding design ranges are shown in Table 3.

[0072] Table 3:

[0073]

[0074] S5: Calculate the corresponding system transfer function according to the optimal reflector position tolerance allocation obtained in step S4; if the current system transfer function meets the target transfer function requirement, output the optimal reflector position tolerance allocation at this time; if the current system transfer function does not meet the target transfer function requirement, repeat steps S1 to S5 until the current system transfer function meets the target transfer function requirement. In this specific embodiment, the target transfer function is set to 0.5, that is, if the system transfer function of the optimized optical system is greater than or equal to 0.5, it indicates that the current system transfer function meets the target transfer function requirement.

[0075] After completing the multi-closed-loop multi-objective optimization method for the space optical imaging system based on the system transfer function described in this specific embodiment, the system transfer function curves of the optimized optical system under different working conditions are as follows: Figure 12~Figure 14 As shown, Figure 12~Figure 14 The horizontal axis represents the spatial frequency unit (cycles / mm), the vertical axis represents (system transfer function), the black line represents the diffraction limit of the optimized optical system, and the three colored lines represent the system transfer functions of the three fields of view (±0.7 and 0 fields of view). Figure 12~Figure 14 It can be seen that the transfer function of the optimized optical system in each field of view is close to the diffraction limit, which shows that the tolerance distribution of the optimized optical system is reasonable. It can be confirmed that the system transfer function of the optical system after tolerance optimization meets the transfer function requirements under different working conditions.

[0076] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the disclosure of the present invention can be performed in parallel, sequentially or in different orders, as long as the desired results of the technical solution disclosed in the present invention can be achieved, and this document does not limit this.

[0077] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A multi-closed-loop multi-objective optimization method for a space optical imaging system based on system transfer function, characterized by: The following steps are involved: S1: Designing the parameters of the optical system with the goal of optimizing the system transfer function and widening the tolerance range, and obtaining the optimal optical surface and the best position of each reflector in the optical system; S2: setting the optimal optical surface and the optimal position obtained in step S1 in the optical system, and performing structural optimization design on the current optical system; The structural optimization design in step S2 includes: S21: Perform mechanical calculations on the current optical system; S22: Calculate the position change and surface error of each reflector in the current optical system; S23: Obtaining the system transfer function of the current optical system according to the mechanical calculation result obtained in step S21 and the position change and surface error of each reflector calculated in step S22; S24: adjusting the optimization parameters in the current optical system, and repeating steps S21 to S23 until the system transfer function of the current optical system reaches the optimum under the mechanical environment conditions, and the total weight of the current optical system is the lowest; S3: Performing temperature optimization design on the optical system obtained in step S2; In the temperature optimization design in step S3, the power of each heating zone in the optical system obtained in step S2 is adjusted so that the system transfer function of the optical system after adjusting the power of each heating zone is optimal and the total power of the heating zones of the optical system is the lowest at this time; S4: repeat steps S1 to S3 N times to obtain N optimization parameters, and respectively calculate the system transfer functions corresponding to the N optimization parameters; construct an approximate fitting model according to the N optimization parameters and the N system transfer functions; determine the optimal parameter of each optimization parameter according to the approximate fitting model through a sensitivity analysis method; In step S4, a structural finite element analysis is performed on each optimization parameter to obtain the position change of each node of the optical surface of each reflector in the optical system corresponding to each optimization parameter; the position change of each node of the optical surface is fitted to obtain the wave aberration, angular displacement and linear displacement of the optical surface; the system transfer function corresponding to each optimization parameter is calculated according to the wave aberration, angular displacement and linear displacement of the optical surface; S5: Calculate the corresponding system transfer function according to the optimal parameters obtained in step S4; if the current system transfer function meets the target transfer function requirements, output the optimal parameters at this time; if the current system transfer function does not meet the target transfer function requirements, repeat steps S1 to S5 until the current system transfer function meets the target transfer function requirements.

2. The multi-closed-loop multi-objective optimization method for a space optical imaging system based on system propagation function according to claim 1, characterized in that: In step S5, when the current system transfer function is greater than or equal to the target transfer function, the target transfer function requirement is met.

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