Space telescope image quality simulation method including shutter

Abstract

The present application belongs to the technical field of photoelectric imaging, and particularly relates to a space telescope image quality simulation calculation method containing a shutter. The method comprises the following steps: firstly, a space telescope optical system model containing a shutter is established; next, simulation image quality of the space telescope optical system model for controlling the whole exposure process is calculated, a shutter opening angle-time variation relationship is established according to a shutter driving curve, and a field of view position-shutter opening angle variation relationship is constructed; finally, a working duration for controlling the whole exposure process is set, and an observation field of view to be calculated is selected for image quality simulation analysis. The present application simulates a complete exposure control process of a space telescope, calculates image quality results of each field of view position, and provides a theoretical reference for processing actual observation data. The present application also calculates the influence of the shutter opening and closing process on the telescope exposure control through simulation results, and provides a theoretical basis for the optimization design of the shutter mechanism.

Description

Technical Field

[0001] This invention belongs to the field of optoelectronic imaging technology, and in particular relates to a method for simulating and calculating the image quality of a space telescope, including a shutter. Background Technology

[0002] In the fields of deep space exploration and astronomical observation, space telescopes are the core equipment for capturing faint deep space signals and conducting high-resolution scientific research. Compared to space cameras (which are often equipped with shutter mechanisms) that require precise control of exposure time, space telescopes, while focusing on high-resolution imaging and faint signal detection, still require precise control of exposure time when observing brighter celestial bodies. Too long an exposure time can easily lead to signal saturation, while too short an exposure time will fail to effectively capture target information. Exposure control has become a key prerequisite for efficient observation in multiple scenarios.

[0003] Rotary opposing mechanical shutter mechanisms are the preferred solution for space telescopes due to their compact structure and rapid response. A drive assembly rotates two blades in opposite directions synchronously, gradually opening and closing the aperture to precisely control exposure. In actual observations, exposure times are typically hundreds of seconds, while the shutter opening and closing transition time is only 1-2 seconds (less than one-thousandth of the total). However, this process can cause fluctuations in image quality data, requiring targeted analysis to eliminate these discrepancies.

[0004] Currently, the field lacks image quality simulation calculation methods capable of simulating the full exposure process, making it difficult to comprehensively assess the impact of the shutter transition phase and providing sufficient theoretical support for data processing, mechanism design optimization, and operational mode improvement. Therefore, developing image quality simulation calculation methods for space telescopes adapted to this type of shutter mechanism has become an important requirement for addressing technical challenges and improving observation performance. Summary of the Invention

[0005] In view of this, the present invention aims to provide a simulation calculation method for the image quality of a space telescope, including the shutter, to solve the problem that existing technologies are unable to fully assess the impact of the shutter transition phase and cannot provide sufficient theoretical support for data processing, mechanism design optimization, and working mode improvement. The present invention calculates the image quality results at each field of view position by simulating the complete process of exposure control of a space telescope, providing a theoretical reference for processing actual observation data; the present invention also calculates the impact of the shutter opening and closing process on the telescope's exposure control through simulation results, providing a theoretical basis for the optimized design of the shutter mechanism.

[0006] To achieve the above objectives, the technical solution created by this invention is implemented as follows:

[0007] A method for simulating the image quality of a space telescope, including a shutter, comprises the following steps:

[0008] S1: Based on the structural parameters of the telescope's optical system, establish a model of the space telescope's optical system, including the shutter.

[0009] S2: Obtain the shutter drive curve. By integrating the angular acceleration of the shutter drive curve, obtain the relationship between the shutter opening angular velocity and time. Also, by integrating the shutter opening angular velocity, obtain the relationship between the shutter opening angle and time.

[0010] S3: Construct the relationship between the field of view position and the shutter opening angle;

[0011] S4: Based on the current field of view position, calculate the shutter opening angle corresponding to the current field of view position; based on the current shutter opening angle, calculate the shutter motion time corresponding to the current shutter opening angle;

[0012] S5: Based on the shutter motion time calculated in step S4, calculate the light intensity ratio between the current field of view position and the central field of view during the entire exposure process of the space telescope optical system model, and calculate the PSF image numerical matrix at the current field of view position.

[0013] S6: Replace the current field of view position with the next field of view position, repeat steps S4-S5, and calculate the light intensity ratio between each field of view position and the central field of view, as well as the PSF image numerical matrix at each field of view position.

[0014] S7: Multiply the light intensity ratio of each field of view position to the central field of view with the PSF image numerical matrix at each field of view position to obtain the corresponding PSF image at each field of view position, thereby achieving image quality evaluation at each field of view position.

[0015] Furthermore, the space telescope image quality simulation calculation method including shutter also includes: S8: compare the image quality evaluation results of each field of view position with the target image quality index. If the image quality evaluation results of each field of view position do not meet the requirements of the target image quality index, change the shutter structure or change the shutter drive curve, and repeat steps S2-S7 until the image quality evaluation results of each field of view position meet the target image quality.

[0016] Furthermore, in step S1, an optical system is constructed based on the structural parameters of the telescope optical system, the initial optical parameters of the optical system are set, and a shutter is set in front of the focal plane of the optical system to establish a space telescope optical system model including the shutter.

[0017] Furthermore, the initial optical parameters include the wavelength of the incident light from the optical system, the field of view, and the position of the focal plane.

[0018] Furthermore, in step S2, the shutter drive curve is a sine wave drive curve, a triangular wave drive curve, or a square wave drive curve.

[0019] Furthermore, in step S3, let the length of the image plane of the space telescope optical system model be p, the width of the image plane be q, and the center field of view of the image plane be O. The overall symmetry central axis of the shutter when all blades are closed passes through point O, and the central axis is perpendicular to the long side of the image plane. The distance between the current field of view point and the central axis is taken as the field of view position. Construct the relationship between the field of view position and the shutter opening angle:

[0020] ;

[0021] in, The position of the field of view. For the width of the image plane in the space telescope optical system model, The shutter opening angle.

[0022] Furthermore, the formula for calculating the ratio of light intensity at the current field of view position to that at the center field of view is:

[0023] ;

[0024] Where t is the shutter speed. t 1 represents the shutter opening time. t 2 represents the exposure time from when the shutter is fully open to when it closes. t 3 represents the shutter closing time, and R represents the light intensity ratio.

[0025] Furthermore, the shutter structure is either a rotating split-type mechanical shutter or an in-lens shutter.

[0026] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0027] (1) The space telescope image quality simulation calculation method containing shutter is created by the present invention. It establishes a simulation image quality calculation method for the entire process of controlling exposure of a space telescope. According to this method, the data difference introduced by the opening or closing of the shutter can be effectively eliminated, and the accuracy of the telescope image quality simulation calculation can be further improved.

[0028] (2) The image quality simulation calculation method of the space telescope containing the shutter described in this invention evaluates the impact of the shutter opening and closing process on the telescope's exposure control through the calculation results. If the impact is significant, the design mechanism of the shutter or the working mode of the shutter is optimized to ensure that the working performance of the telescope meets the development requirements.

[0029] (3) The image quality simulation calculation method for space telescopes containing shutter described in this invention is based on the simulation data obtained by this invention, and the processing flow of actual observation data is designed in advance, which shortens the test cycle and reduces the development cost. Attached Figure Description

[0030] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0031] Figure 1 A flowchart illustrating the image quality simulation calculation method for a space telescope including a shutter, as described in an embodiment of the present invention;

[0032] Figure 2 A schematic diagram of the structure of a space telescope optical system model including a shutter, as described in an embodiment of the present invention;

[0033] Figure 3 A schematic diagram illustrating the relationship between shutter opening angle and time, determined based on different drive curves, as described in an embodiment of the present invention.

[0034] Figure 4 An enlarged schematic diagram illustrating the relationship between shutter opening angle and time, corresponding to a sine wave as the shutter drive curve, as described in an embodiment of the present invention.

[0035] Figure 5 A schematic diagram of the spatial relationship between the blades and the image plane of the space telescope optical system including the shutter, as described in an embodiment of the present invention;

[0036] Figure 6 A flowchart of image quality simulation calculation for the entire process of controlling exposure with a shutter in a space telescope, as described in an embodiment of the present invention;

[0037] Figure 7 Energy distribution map of the PSF image described in the embodiment of the present invention.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1. Primary mirror; 2. Secondary mirror; 3. Third mirror; 4. Fast-swinging mirror; 5. Leaf mirror; 6. Image plane. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0041] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0042] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0043] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0044] Taking a rotating, opposing mechanical shutter mechanism as an example, this invention, after activating the staring mode, drives two shutter blades 5 to rotate synchronously in opposite directions at the same angular velocity. This allows the space telescope's optical system to gradually form a complete light-passing aperture. After exposure, the blades 5 rotate in the opposite direction again to close, blocking light from entering the detector, thus achieving precise control of the exposure time. When photographing brighter celestial bodies, the exposure time of a space telescope is typically several hundred seconds, while the shutter opening or closing time is only 1-2 seconds. The image quality data captured during shutter movement varies, and the working time during this period is less than one-thousandth of the total exposure time. Accurate data analysis is necessary to eliminate data differences introduced by shutter opening and closing. This invention can accurately calculate the simulated image quality of the entire exposure control process of the space telescope's observation field, providing a theoretical reference for processing actual observation data. Simultaneously, by evaluating the impact of the shutter opening and closing process on the telescope's exposure control through simulation results, it provides a theoretical basis for optimizing the shutter mechanism design and improving the working mode (shutter drive curve).

[0045] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0046] like Figures 1-4As shown, this invention proposes a method for simulating the image quality of a space telescope including a shutter. The specific steps include: S1: Establishing a model of the space telescope's optical system including a shutter based on the structural parameters of the telescope's optical system; S2: Obtaining the shutter drive curve, and obtaining the relationship between the shutter opening angular velocity and time by integrating the angular acceleration of the shutter drive curve, and obtaining the relationship between the shutter opening angle and time by integrating the shutter opening angular velocity; S3: Constructing the relationship between the field of view position and the shutter opening angle; S4: Calculating the shutter opening angle corresponding to the current field of view position. S4: Based on the current shutter opening angle, calculate the shutter motion time corresponding to the current shutter opening angle; S5: Based on the shutter motion time calculated in step S4, calculate the light intensity ratio between the current field of view and the central field of view throughout the entire exposure process of the space telescope optical system model, and calculate the PSF image numerical matrix at the current field of view; S6: Replace the current field of view with the next field of view, repeat steps S4-S5, and calculate the light intensity ratio between each field of view and the central field of view, as well as the PSF image numerical matrix at each field of view (the PSF image numerical matrix uses Code). S7: Multiply the light intensity ratio of each field of view position to the central field of view with the PSF image numerical matrix at each field of view position to obtain the PSF image at each field of view position, thus evaluating the image quality at each field of view position; S8: Compare the image quality evaluation results at each field of view position with the target image quality index. If the image quality evaluation results at each field of view position do not meet the requirements of the target image quality index, change the shutter structure or change the shutter drive curve, and repeat steps S2-S7 until the image quality evaluation results at each field of view position meet the target image quality.

[0047] It should be noted that the proposed method for simulating the image quality of a space telescope, which includes a shutter, involves the following steps: First, a model of the space telescope's optical system, including a shutter (such as a rotating, opposing mechanical shutter structure), is established. This model comprises key optical components such as the primary mirror 1, secondary mirror 2, third mirror 3, fast-swinging mirror 4, and image plane 6, as well as a mechanical shutter. Ray tracing is then performed on the central field of view. Figure 2 In (a), the shutter blades 5 are in the closed state, and the focal plane detector does not receive light from the center field of view. Figure 2In (b), the shutter blades 5 are in the open state, and the focal plane detector receives all the light from the central field of view. An optical system is established based on the structural parameters of the telescope's optical system. Initial optical parameters such as the incident wavelength, observation field of view, and focal plane position are set. Then, the shutter is set in front of the focal plane (the specific position is set according to actual needs), and the aperture of the optical system is controlled by adjusting the structure of the shutter blades 5. Next, the simulated image quality of the entire controlled exposure process of the space telescope's optical system model is calculated. The relationship between the rotation angle of blades 5 and time is established based on the shutter working mode (controlled by the shutter drive curve). The working time of the entire controlled exposure process is set, and the light intensity distribution of the observation field is calculated for the three processes: shutter opening, shutter fully open, and shutter closing. The numerical results of the three processes are superimposed to obtain the light intensity distribution value for the entire controlled exposure process, and finally, the simulated image quality is calculated. Finally, based on the image quality simulation calculation results, the shutter design structure was improved, and the shutter operating mode was optimized. The image quality index satisfaction of controlling the entire exposure process was evaluated based on the image quality simulation calculation results. If it exceeded the development target, it could be improved by optimizing the shutter structure or opening and closing mode (changing the shutter drive curve). At the same time, the simulated image quality after the improvement was calculated again, and the calculation results can be used to determine whether the improvement was effective or had a significant change.

[0048] Furthermore, PSF images at each field of view are typically calculated using optical software, and each PSF image should be acquired instantaneously. The PSF images calculated over the exposure time should be dynamic PSF images, obtained by superimposing the PSF images at each transient moment. This invention assumes that the transient PSF images for each field of view remain constant during the exposure time; that is, the final dynamic PSF image used to evaluate image quality equals the transient PSF image multiplied by the exposure time. The exposure time differs for different fields of view, which can be indirectly reflected by the light intensity distribution across the entire field of view. Therefore, the final dynamic PSF image used to evaluate image quality equals the transient PSF image (the PSF image numerical matrix at the current field of view position) multiplied by the light intensity ratio of each field of view position to the central field of view. Additionally, changing the shutter structure will change the relationship between the shutter opening angle and time; therefore, after changing the shutter structure, the shutter drive curve needs to be re-acquired for subsequent calculations.

[0049] This invention has two objectives. First, to calculate the image quality changes of a space telescope during shutter opening and closing, and then to calculate the simulated image quality of the entire exposure control process, providing a theoretical reference for subsequent processing of actual observation data. Second, to evaluate the impact of shutter opening and closing on telescope exposure control through simulation results, providing a theoretical basis for shutter mechanism design optimization and working mode improvement.

[0050] In some embodiments, in step S1, an optical system is constructed based on the structural parameters of the telescope optical system, the initial optical parameters of the optical system are set, and a shutter is set in front of the focal plane of the optical system to establish a space telescope optical system model including the shutter.

[0051] It should be noted that the optical system model of the space telescope, which includes the shutter, is built based on Code V software.

[0052] In some embodiments, the initial optical parameters include the wavelength of the incident light from the optical system, the field of view, and the focal plane position.

[0053] In some embodiments, the shutter drive curve is a sine wave drive curve, a triangular wave drive curve, or a square wave drive curve.

[0054] It should be noted that this invention can select sine waves, triangular waves, and square waves as shutter drive curves. By integrating the angular acceleration of the shutter drive curve, the relationship between the shutter opening angular velocity and time can be obtained. Then, by integrating the shutter opening angular velocity, the relationship between the shutter opening angle and time can be obtained. Figure 3 (a) in the figure is a schematic diagram using a sine wave as the shutter drive curve. Figure 3 (b) in the diagram is a schematic diagram using a triangular wave as the shutter drive curve. Figure 3 (c) in the diagram is a schematic diagram using a square wave as the shutter drive curve. Figure 3 (d) in the figure is a schematic diagram showing the relationship between the shutter angular velocity and time corresponding to the sinusoidal drive curve. Figure 3 (e) in the diagram illustrates the relationship between the shutter angular velocity and time corresponding to the triangular wave drive curve. Figure 3 (f) in the diagram illustrates the relationship between the shutter angular velocity and time corresponding to the square wave drive curve. Figure 3 (g) in the figure is a schematic diagram showing the relationship between the shutter opening angle and time corresponding to the sinusoidal drive curve. Figure 3 In the diagram, (h) represents the relationship between the shutter opening angle and time corresponding to the triangular wave drive curve. Figure 3 In the diagram, (i) illustrates the relationship between the shutter opening angle and time corresponding to the square wave drive curve. Taking the sine wave drive curve as an example, the calculation shows the relationship between the corresponding shutter angle and time, as follows: Figure 4 As shown, at time t, the shutter opening angle is θ.

[0055] Furthermore, in step S2, as Figure 3 As shown, taking a sinusoidal drive curve as an example, the relationship between the shutter opening angular acceleration and time t is as follows:

[0056] ;

[0057] Where k is a constant component, A is the amplitude, and ν is the angular frequency. For phase.

[0058] Based on the state when the shutter opens, we know that when time... t When =0, shutter opening angular acceleration α ( t )=0, assuming amplitude A =3π, angular frequency ν =2π, the above formula can be written as:

[0059] ;

[0060] Given that the shutter opening angular velocity is equal to the integral of the shutter opening angular acceleration over time, therefore:

[0061] ;

[0062] ;

[0063] in, This shows the relationship between the shutter opening angular velocity and time t. is the integration constant.

[0064] Similarly, based on the state when the shutter is open, we know that when t=0, ω(t)=0, and we can obtain... =0. The shutter opening angle is equal to the integral of the shutter opening angular velocity over time, which gives:

[0065] ;

[0066] ;

[0067] in, This describes the relationship between the shutter opening angle and time t. is the integration constant.

[0068] when t When =0, θ ( t ) = 0, thus obtaining C 2 = 0. Therefore, the relationships between shutter opening angular acceleration, shutter opening angular velocity, and shutter opening angle as a function of time can be obtained as follows:

[0069] ;

[0070] In some embodiments, in step S3, the length of the image plane 6 of the space telescope optical system model is p, the width of the image plane 6 is q, and the center field of view of the image plane 6 is O. The overall symmetry central axis of all shutter blades 5 when closed passes through point O, and the central axis is perpendicular to the long side of the image plane 6. The distance between the current field of view point and the central axis is taken as the field of view position. Construct the relationship between the field of view position and the shutter opening angle:

[0071] ;

[0072] in, The position of the field of view. The width of image plane 6 in the model of the space telescope's optical system. The shutter opening angle.

[0073] It should be noted that blade 5 is in a closed state, covering the image plane 6. The light intensity value at a certain field of view F on the image plane 6 is calculated, assuming the vertical distance of field of view F from the central axis is... ,like Figure 5 As shown in (a), Figure 5 (a) in the image is a top-down view of the space telescope detector, including the shutter; as shown in the image. Figure 5 As shown in (b) in the figure, Figure 5 Figure (b) shows a schematic diagram of the shutter opening angle θ of one side blade of the space telescope detector. When the opening angle of one side blade 5 is θ, the field of view point F can receive the incident light. At this time, the correspondence between the field of view position and the shutter opening angle can be seen. Therefore, it can be seen that at time t, the shutter opening angle θ and the vertical distance to the central axis are less than 1 / 2. The entire field of view can receive incident light.

[0074] In some embodiments, the formula for calculating the ratio of light intensity at the current field of view position to that at the center field of view is:

[0075] ;

[0076] Where t is the shutter speed. t 1 represents the shutter opening time. t 2 represents the exposure time from when the shutter is fully open to when it closes. t 3 represents the shutter closing time, and R represents the light intensity ratio.

[0077] It should be noted that, based on the field of view position, the required shutter opening and closing angle θ can be calculated. Based on the relationship between the shutter opening angle and time, the shutter's motion time t can be obtained. It is assumed that the shutter closing drive curve remains consistent with the opening curve, i.e. This allows us to construct the relationship between the field of view position and the shutter opening angle. Similarly, after obtaining the relationship between the field of view position and the shutter closing angle, we accumulate the light intensity distribution values ​​throughout the entire shutter operation process, calculate the light intensity distribution of the entire field of view of the detector, and then evaluate the imaging quality of the entire field of view, such as... Figure 6 As shown.

[0078] Finally, after improving the shutter structure or working mode (shutter drive curve), the relationship curve of shutter opening angle changing with time changes. The above method is used again to calculate the simulated image quality and control the image quality index satisfaction of the entire exposure process.

[0079] The process of evaluating image quality at each field of view location based on the PSF image is as follows: Figure 7 As shown, taking the space telescope optical system model described in this invention as an example, PSF images are obtained through ray tracing. The sampling number is set to 512×512, and the sampling interval is 0.4 micrometers. First, the centroid position of the PSF image is calculated. :

[0080] ;

[0081] ;

[0082] Where P represents the number of samples, Let be the row coordinates of the pixel in the i-th row and j-th column of the PSF image. This represents the column coordinate position of the pixel in the i-th row and j-th column of the PSF image. This represents the value in the i-th row and j-th column of the PSF image digital matrix.

[0083] Then, the energy concentration angular radius R of the PSF image matrix is ​​calculated with the centroid as the center. The calculation method is to set the energy concentration value to a specified value, such as 0.9. Finally, the sum of the values ​​inside the ring is equal to 90% of the total sum of the PSF image matrix values, and the radius value is solved. At this time, the image quality of the PSF image is evaluated by the size of the radius value, that is, the smaller the radius value R, the better the image quality.

[0084] The shutter opening angle of the present invention is achieved by the dynamic change of the blade 5. The dynamic change of the blade 5 includes rotation, closing, etc., depending on the specific structure.

[0085] 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 this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0086] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for simulating the image quality of a space telescope, including a shutter, characterized in that: The specific steps include: S1: Based on the structural parameters of the telescope's optical system, establish a model of the space telescope's optical system, including the shutter. S2: Obtain the shutter drive curve. By integrating the angular acceleration of the shutter drive curve, obtain the relationship between the shutter opening angular velocity and time. Also, by integrating the shutter opening angular velocity, obtain the relationship between the shutter opening angle and time. S3: Construct the relationship between the field of view position and the shutter opening angle; In step S3, let the length of the image plane of the space telescope optical system model be p, the width of the image plane be q, and the center field of view of the image plane be O. The overall symmetry central axis of the shutter when all blades are closed passes through point O, and the central axis is perpendicular to the long side of the image plane. The distance between the current field of view point and the central axis is taken as the field of view position. Construct the relationship between the field of view position and the shutter opening angle: ； in, The position of the field of view. For the width of the image plane in the space telescope optical system model, The shutter opening angle; The formula for calculating the ratio of light intensity at the current field of view position to that at the center field of view is: ； Where t is the shutter speed. t 1 represents the shutter opening time. t 2 represents the exposure time from when the shutter is fully open to when it closes. t 3 represents the shutter closing time, and R represents the light intensity ratio; S4: Based on the current field of view position, calculate the shutter opening angle corresponding to the current field of view position; based on the current shutter opening angle, calculate the shutter motion time corresponding to the current shutter opening angle; S5: Based on the shutter motion time calculated in step S4, calculate the light intensity ratio between the current field of view position and the central field of view during the entire exposure process of the space telescope optical system model, and calculate the PSF image numerical matrix at the current field of view position. Calculate the centroid position of the PSF image : ； ； Where P represents the number of samples, Let be the row coordinates of the pixel in the i-th row and j-th column of the PSF image. This represents the column coordinate position of the pixel in the i-th row and j-th column of the PSF image. This represents the value in the i-th row and j-th column of the PSF image digital matrix; S6: Replace the current field of view position with the next field of view position, repeat steps S4-S5, and calculate the light intensity ratio between each field of view position and the central field of view, as well as the PSF image numerical matrix at each field of view position. S7: Multiply the light intensity ratio of each field of view position to the central field of view with the PSF image numerical matrix at each field of view position to obtain the corresponding PSF image at each field of view position, thereby achieving image quality evaluation at each field of view position.

2. The method for simulating the image quality of a space telescope including a shutter according to claim 1, characterized in that: The space telescope image quality simulation calculation method including shutter further includes: S8: comparing the image quality evaluation results of each field of view position with the target image quality index. If the image quality evaluation results of each field of view position do not meet the requirements of the target image quality index, then change the shutter structure or change the shutter drive curve, and repeat steps S2-S7 until the image quality evaluation results of each field of view position meet the target image quality.

3. The method for simulating the image quality of a space telescope including a shutter according to claim 1, characterized in that: In step S1, an optical system is constructed based on the structural parameters of the telescope optical system, the initial optical parameters of the optical system are set, and a shutter is set in front of the focal plane of the optical system to establish a space telescope optical system model including the shutter.

4. The method for simulating the image quality of a space telescope including a shutter according to claim 1, characterized in that: The initial optical parameters include the wavelength of the incident light, the field of view, and the position of the focal plane of the optical system.

5. The method for simulating the image quality of a space telescope including a shutter according to claim 1, characterized in that: In step S2, the shutter drive curve is a sine wave drive curve, a triangular wave drive curve, or a square wave drive curve.

6. The method for simulating the image quality of a space telescope including a shutter according to claim 1, characterized in that: The shutter structure is either a rotating split-type mechanical shutter or an in-lens shutter.

Images