Wavefront error detection method for primary and secondary mirror optical system

Abstract

The invention discloses a wavefront error detection method for a primary and secondary mirror optical system, which belongs to the technical field of optical detection, and specifically comprises the following steps: establishing a performance prediction model, and calculating ideal wavefront phase distribution; acquiring a point spread function image through a detector, and recovering actual wavefront phase distribution by using an iterative phase recovery algorithm; performing dynamic adaptive calibration, monitoring and updating a wavefront phase in real time, comparing the dynamically calibrated wavefront phase with an ideal wavefront phase, calculating an error and predicting a variation trend by using an adaptive wavefront error compensation algorithm, and correcting the wavefront error in real time by using an adaptive optical method; and repeating the steps until a preset wavefront error threshold value is met. The method improves the performance stability and precision of the primary and secondary mirror optical system, and is suitable for error correction of a high-precision optical system.

Description

Technical Field

[0001] The invention belongs to the technical field of optical detection, and in particular is a wavefront error detection method for a primary-secondary mirror optical system. Background Art

[0002] In optical systems, primary and secondary mirror optical systems are widely used in astronomical telescopes, high-resolution imaging systems and other fields. Wavefront error is one of the key indicators to measure the imaging quality of optical systems. Accurate detection of the wavefront error of primary and secondary mirror optical systems is crucial to improving the performance of optical systems. Traditional wavefront error detection methods have problems such as low detection accuracy, complex detection process, and high environmental requirements, which are difficult to meet the detection needs of modern high-precision optical systems.

[0003] For example, a Chinese patent with authorization announcement number CN108225187B discloses a method for detecting aspheric lens errors based on wavefront sensing, including: obtaining the correspondence between the wavefront Zernike term of the lens and the lens processing error; based on the correspondence, using the actual wavefront of the aspheric lens to be tested to trace the processing error of the aspheric lens; wherein, the process of obtaining the correspondence specifically includes: taking a number of aspheric lens materials for analysis, performing wavefront detection and simulation respectively, and calculating the deviation between the actual and theoretical wavefronts of each of the aspheric lens materials; according to the principle of approximate distribution of the same error, performing systematic clustering and correlation analysis on multiple Zernike terms with unknown coefficients measured by wavefront simulation to determine typical Zernike terms that can represent different processing errors. The method of this technical solution belongs to non-contact detection, which is convenient and fast, and the detection process is not affected by subjective factors of the operator, and is relatively accurate; it can be used in particular for real-time online error detection on processing lines.

[0004] The above existing technologies have the following problems: they are mainly applicable to the production and quality control of aspheric lenses, which leads to limited scope of application; they trace the detection error through the correspondence between the wavefront Zernike term and the lens processing error. Although it is non-contact and fast, it is not sensitive enough to certain specific types of processing errors and it is difficult to accurately distinguish different types of error sources; there is a lack of dynamic feedback and adaptive adjustment mechanism. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention proposes a wavefront error detection method for the primary and secondary mirror optical system, establishes a performance prediction model, calculates the ideal wavefront phase distribution; collects point spread function images through the detector, and uses the iterative phase recovery algorithm to restore the actual wavefront phase distribution; performs dynamic adaptive calibration, monitors and updates the wavefront phase in real time, and compares the wavefront phase after dynamic calibration with the ideal wavefront phase, uses an adaptive wavefront error compensation algorithm to calculate the error and predict the change trend, and at the same time, uses an adaptive optical method to correct the wavefront error in real time; repeats the above steps until the preset wavefront error threshold is met. The present invention improves the performance stability and accuracy of the primary and secondary mirror optical system, and is suitable for error correction of high-precision optical systems.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A wavefront error detection method for a primary-secondary mirror optical system, comprising:

[0008] Step S1: Establishing a performance prediction model for the primary and secondary mirror optical system;

[0009] Step S2: Based on the established performance prediction model of the primary and secondary mirror optical system, under the ideal condition that the optical system has no errors, the ideal wavefront phase distribution of the target light source at the focal plane after passing through the optical system is calculated;

[0010] Step S3: placing a detector at the focal plane of the optical system, collecting a point spread function image of the target light source after passing through the optical system, and using an iterative phase recovery algorithm to recover the actual wavefront phase distribution of the optical system according to the intensity information of the point spread function image;

[0011] Step S4: Based on the restored wavefront phase distribution, dynamic adaptive calibration is performed, and at the same time, the change of the wavefront phase is monitored in real time, and the change is fed back to the primary and secondary mirror optical system performance prediction model for updating, so as to obtain the updated primary and secondary mirror optical system performance prediction model and the wavefront phase distribution after dynamic calibration;

[0012] Step S5: comparing the dynamically calibrated wavefront phase distribution with the ideal wavefront phase distribution point by point, calculating the wavefront error, and predicting the wavefront error change trend in combination with the updated primary and secondary mirror optical system performance prediction model;

[0013] Step S6: Correcting the wavefront error of the optical system in real time according to the wavefront error and the prediction of the wavefront error change trend;

[0014] Step S7: Repeat steps S2 to S6 until a preset wavefront error threshold is met.

[0015] Specifically, the specific steps of step S2 include:

[0016] S2.1: Determine the wavelength of the target light source and amplitude distribution ,in, Indicates that the target light source is on the initial plane The amplitude distribution on , where and Respectively represent the abscissa and ordinate values ​​of the initial plane;

[0017] S2.2: Based on the established performance prediction model of the primary and secondary mirror optical system, the ray tracing method of geometric optics is used to calculate the propagation path of the light emitted from the target light source to the primary and secondary mirror surfaces;

[0018] S2.3: Continue tracing the light, calculate the propagation path of the light after reflection from the primary and secondary mirrors to the focal plane and the propagation path of the light after reflection to the focal plane, and obtain the coordinates of the intersection of the light on the focal plane ,in, and Respectively represent the horizontal and vertical coordinate values ​​of the intersection point of the light on the focal plane;

[0019] S2.4: For each traced ray, calculate the total optical path from the target light source, through reflection from the primary and secondary mirrors, to any point on the focal plane. ,and , N represents the number of rays emitted by the target light source;

[0020] S2.5: Select a reference light path As a benchmark, the optical path difference of the i-th light relative to the reference light is obtained by difference calculation. ;

[0021] S2.6: Based on the optical path difference , using the relationship between phase and optical path to calculate the phase of each point on the focal plane , where x and y represent the horizontal and vertical coordinate values ​​respectively;

[0022] S2.7: Arrange the calculated phase values ​​of each point on the focal plane into a two-dimensional array to obtain the ideal wavefront phase distribution of the target light source at the focal plane. , and use drawing software to display the ideal wavefront phase distribution in the form of an image.

[0023] Specifically, the specific steps of S2.2 include:

[0024] S2.21: extracting the parameters of the primary mirror and the secondary mirror from the primary-secondary mirror optical system performance prediction model, wherein the parameters of the primary mirror and the secondary mirror include the curvature radius, the aperture, the spacing between the primary mirror and the secondary mirror, and the vertex position coordinates of the primary and secondary mirrors;

[0025] S2.22: Based on the property that light travels in a straight line in a homogeneous medium, establish the light propagation equation ,in, represents the position vector of the light, d represents the distance the light travels from the initial point, represents the initial position vector of the light, represents the direction vector of the light, Represents the position coordinates of the target light source, Indicates the vertical coordinate value of the target light source. Indicates the initial emission direction of the light;

[0026] S2.23: Use the standard spherical equation as the primary mirror equation, substitute the light propagation equation into the primary mirror equation, solve the quadratic equation system, and obtain the coordinates of the intersection of the light and the primary mirror. ,in, , and Respectively represent the horizontal, vertical and vertical coordinate values ​​of the intersection point of the light ray with the primary mirror;

[0027] S2.24: Coordinates of the intersection of the light ray and the primary mirror By taking the gradient of the primary mirror equation, we can get the normal vector of the primary mirror surface. ;

[0028] S2.25: According to the law of reflection, the direction vector of the incident light and the normal vector to the primary mirror surface Calculate the direction vector of the reflected light on the primary mirror surface ;

[0029] S2.26: The coordinates of the intersection of the light ray and the primary mirror As the new starting point, the direction vector of the reflected light from the primary mirror surface As the new direction, update the light propagation equation to ,in, represents the distance the light travels from the reflection point of the primary mirror, represents the coordinates of the intersection of the light ray and the primary mirror, that is, .

[0030] Specifically, the specific steps of S2.2 also include:

[0031] S2.27: Use the standard spherical equation as the secondary mirror equation, and substitute the updated light propagation equation into the secondary mirror equation to solve the quadratic equation system to obtain the coordinates of the intersection of the light and the secondary mirror. , and calculate the direction vector of the reflected light on the secondary mirror surface according to S2.24-S2.25 ,in, , and Respectively represent the horizontal, vertical and vertical coordinate values ​​of the intersection point of the light ray with the secondary mirror;

[0032] S2.28: According to and , determine whether the light is on the mirror surface;

[0033] like , then the intersection of the light and the primary mirror is at the aperture of the primary mirror within the scope;

[0034] like , then the intersection of the light and the primary mirror is at the aperture of the secondary mirror within the scope;

[0035] S2.29: If the intersection of the ray and the primary mirror is within the aperture of the primary mirror The intersection of the light and the primary mirror is within the aperture of the secondary mirror. If it is within the range, it means that the light is on the mirror surface;

[0036] If the light is on the mirror surface, the propagation path of the light from the target light source, reflected by the primary mirror, and then to the secondary mirror is recorded, including the position coordinates of the target light source, the coordinates of the intersection of the light and the primary mirror, the coordinates of the intersection of the light and the secondary mirror, and the corresponding direction vector of the reflected light.

[0037] Specifically, the specific steps of S2.3 include:

[0038] S2.31: Get the vertex position coordinates of the primary and secondary mirrors, and calculate the distance from the focal plane to the vertex of the primary mirror based on the vertex position coordinates of the primary and secondary mirrors and the distance formula from the point to the plane. ;

[0039] S2.32: Establish the focal plane equation based on the distance from the focal plane to the vertex of the primary mirror ;

[0040] S2.33: Transform the focal plane equation Substituting into the updated expression of the light propagation equation, we get ;

[0041] S2.34: Substitute the calculated d value into the updated light propagation equation to obtain the coordinates of the intersection point of the light on the focal plane .

[0042] Specifically, the specific steps of S2.4 include:

[0043] S2.41: During ray tracing, based on the position coordinates of the target light source , the coordinates of the intersection of the light and the primary mirror , the coordinates of the intersection of the light ray and the secondary mirror The coordinates of the intersection point with the light on the focal plane , use the distance formula between two points in space to calculate the geometric distance from the target light source to the primary mirror , the geometric distance from the primary mirror to the secondary mirror , the geometric distance from the secondary mirror to the focal plane ;

[0044] S2.42: By , , Sum and obtain the total optical path of the ith traced ray .

[0045] Specifically, the specific steps of step S3 include:

[0046] S3.1: Place the detector at the focal plane of the optical system to collect images, and average the collected images to obtain the point spread function image of the target light source after passing through the optical system. ;

[0047] S3.2: Setting the initial wavefront phase distribution , combined with the intensity information of the collected point spread function image, construct the initial complex amplitude distribution ;

[0048] S3.3: Distribute the initial complex amplitude The forward propagation model of the optical system propagates to an intermediate plane and obtains the complex amplitude distribution of the intermediate plane. ,in, represents the coordinates of the midplane;

[0049] S3.4: In the middle plane, the complex amplitude distribution is adjusted according to the physical constraints of the optical system. Correction is made and the corrected complex amplitude distribution in the middle plane is Propagate back to the focal plane through the back propagation model to obtain the new focal plane complex amplitude distribution .

[0050] Specifically, the specific steps of step S3 also include:

[0051] S3.5: Maintain the new focal plane complex amplitude distribution Phase information , and combined with the intensity information of the collected point spread function image , construct the updated focal plane complex amplitude distribution ;

[0052] S3.6: Use the mean square error formula to calculate the difference MSE between the complex amplitude distributions obtained from two adjacent iterations;

[0053] S3.7: Set an error threshold ;

[0054] like , then the updated complex amplitude distribution As the initial value of the next iteration, return to S3.3 to continue the iteration;

[0055] like , the iteration is considered to have converged and the iteration process is terminated;

[0056] S3.8: When the iteration is terminated, the final complex amplitude distribution The phase part That is the restored actual wavefront phase distribution of the optical system.

[0057] Specifically, the specific steps of step S4 include:

[0058] S4.1: Obtain the actual wavefront phase distribution of the restored optical system and performance prediction models of primary and secondary mirror optical systems;

[0059] S4.2: Determine a set of parameters that require dynamic adaptive calibration based on the application requirements and performance indicators of the optical system;

[0060] S4.3: Based on optical theory, establish a mathematical model between calibration parameters and wavefront phase change;

[0061] S4.4: Using the optical adjustment device, adjust the primary and secondary mirrors according to the preset calibration strategy, monitor the change of the wavefront phase in real time, and record the initial data;

[0062] S4.5: At time intervals Collect wavefront phase data and compare the real-time monitored wavefront phase change with the expected wavefront phase change to obtain the wavefront phase difference , according to the wavefront phase difference value, the feedback amount that needs to be fed back to the performance prediction model of the primary and secondary mirror optical systems is calculated through the PID control algorithm;

[0063] S4.6: According to the feedback, the parameters of the primary and secondary mirror optical system performance prediction model are updated, and the updated primary and secondary mirror optical system performance prediction model is recalculated and generated using the updated parameters, and the wavefront phase distribution after dynamic calibration is recorded at the same time .

[0064] Specifically, the specific steps of step S5 include:

[0065] S5.1: Obtaining the wavefront phase distribution after dynamic calibration and the updated performance prediction model of the primary and secondary mirror optical system, and set the ideal wavefront phase distribution ;

[0066] S5.2: For each coordinate point on the focal plane , the wavefront phase distribution after dynamic calibration Compared with the ideal wavefront phase distribution Compare and calculate the difference to obtain the wavefront error , and the calculated wavefront error Conduct mean analysis;

[0067] S5.3: Combine the updated performance prediction model of the primary and secondary mirror optical system with the wavefront error information As input parameters, the optical propagation and transformation relations in the updated performance prediction model of the primary and secondary mirror optical system are used to predict the changing trend of the wavefront error under different time changes.

[0068] Compared with the prior art, the present invention has the following beneficial effects:

[0069] 1. The present invention proposes a wavefront error detection method for primary and secondary mirror optical systems. The method can monitor and accurately calculate the wavefront errors of primary and secondary mirror optical systems in real time by establishing a performance prediction model, restoring the actual wavefront phase distribution, and dynamically adaptive calibration, thereby effectively improving the accuracy and stability of the optical system. Through this method, errors in the optical system can be discovered and corrected in a timely manner, ensuring that the optical system is always in the best working state.

[0070] 2. The present invention proposes a wavefront error detection method for primary and secondary mirror optical systems. The method also combines the prediction of the wavefront error change trend to achieve continuous optimization of the optical system performance. By continuously iteratively updating the performance prediction model and wavefront phase distribution, the method can gradually approach the ideal wavefront phase distribution until the preset wavefront error threshold is met, which not only improves the performance of the optical system, but also reduces maintenance costs and time. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 A schematic diagram of a wavefront error detection method for a primary and secondary mirror optical system according to the present invention;

[0072] Figure 2 This is a principle flow chart of a wavefront error detection method for a primary and secondary mirror optical system of the present invention;

[0073] Figure 3The present invention is a flow chart for realizing the propagation path of light reaching the primary and secondary mirror surfaces in a wavefront error detection method for a primary and secondary mirror optical system. DETAILED DESCRIPTION

[0074] Example 1

[0075] See also Figure 1 and Figure 2 , an embodiment of the present invention provides: a wavefront error detection method for a primary-secondary mirror optical system, comprising the following steps:

[0076] Step S1: Establishing a performance prediction model for the primary and secondary mirror optical system;

[0077] Furthermore, the specific process of establishing the performance prediction model of the primary and secondary mirror optical system includes:

[0078] (1) Determine the performance parameters and dimensions of the primary and secondary mirror optical systems based on the conditions of use;

[0079] (2) Draw up a schematic diagram of the optical system and determine the basic optical properties, such as magnification, focal length, linear field of view, and numerical aperture. This stage is usually carried out according to the theory of ideal optical systems.

[0080] (3) Based on the primary aberration theory, find the initial structure that meets the imaging quality requirements. The selection of the initial structure is the basis of lens design.

[0081] (4) Calculate the optical path on a computer and use the automatic aberration correction program to correct the aberration;

[0082] (5) Draw the aberration curve based on the calculation results, analyze the aberration, find out the cause, and perform repeated calculations and balance until the imaging quality requirements are met;

[0083] (6) Based on the above design results, the optical design software CODEV is used to design a model and establish a performance prediction model for the primary and secondary mirror optical system. The model should be able to predict key performance parameters such as the imaging quality and wavefront phase distribution of the system;

[0084] (7) Conduct simulation analysis to verify the rationality and accuracy of the model, and evaluate the performance of the system based on the simulation results.

[0085] Step S2: Based on the established performance prediction model of the primary and secondary mirror optical system, under the ideal condition that the optical system has no errors, the ideal wavefront phase distribution of the target light source at the focal plane after passing through the optical system is calculated;

[0086] Step S3: placing a detector at the focal plane of the optical system, collecting a point spread function image of the target light source after passing through the optical system, and using an iterative phase recovery algorithm to recover the actual wavefront phase distribution of the optical system according to the intensity information of the point spread function image;

[0087] Step S4: Based on the restored wavefront phase distribution, dynamic adaptive calibration is performed, and at the same time, the change of the wavefront phase is monitored in real time, and the change is fed back to the primary and secondary mirror optical system performance prediction model for updating, so as to obtain the updated primary and secondary mirror optical system performance prediction model and the wavefront phase distribution after dynamic calibration;

[0088] Step S5: comparing the dynamically calibrated wavefront phase distribution with the ideal wavefront phase distribution point by point, calculating the wavefront error, and predicting the wavefront error change trend in combination with the updated primary and secondary mirror optical system performance prediction model;

[0089] Step S6: Correcting the wavefront error of the optical system in real time according to the wavefront error and the prediction of the wavefront error change trend;

[0090] Furthermore, the specific steps of step S6 include:

[0091] (1) Extract wavefront error distribution data from previous calculation results , the wavefront error distribution data describes the difference between the actual wavefront phase and the ideal wavefront phase at each point on the focal plane;

[0092] (2) Based on the prediction results of the wavefront error change trend, determine the trend of the wavefront error change over time, environmental factors, or system internal parameters, and clarify whether the error increases, decreases, or remains stable, as well as the rate of change;

[0093] (3) Selecting an adaptive optical element according to the characteristics and variation trend of the wavefront error; the adaptive optical element comprises:

[0094] Deformable mirror: suitable for correcting high-order aberrations and can compensate for complex wavefront error distribution by changing the shape of the mirror;

[0095] Tilt mirror: mainly used to correct the overall tilt and low-order aberrations of the wavefront, and can quickly adjust the propagation direction of light;

[0096] Adjustable liquid lens: can change its own curvature and make continuous and local corrections to the wavefront, often used to compensate for small aberrations and focusing errors;

[0097] (4) using the least squares method to calculate the control parameters of the adaptive optical element, wherein the least squares method is a prior art in the art and is not an inventive solution of the present application, and is not described in detail herein;

[0098] (5) Establishing a mapping relationship between the wavefront error and the control parameters of the adaptive optical element. For example, for a deformable mirror, the relationship between the displacement of each actuator and the wavefront error can be obtained through optical simulation or experimental measurement.

[0099] (6) Solving the control parameters of the adaptive optical element based on the least squares method and the established mapping relationship. For example, using the least squares method to solve the driving voltage or displacement of each actuator of the deformable mirror;

[0100] (7) Convert the calculated control parameters into actual drive signals, such as voltage and current;

[0101] (8) applying a driving signal to the adaptive optical element through a driver to cause a corresponding physical change to occur, thereby correcting the wavefront error; the physical change may be a deformation of the mirror surface or a tilt of the lens;

[0102] (9) Use a wavefront sensor to monitor the corrected wavefront error in real time, and feed the new wavefront error data into the control algorithm to recalculate the control parameters and adjust the adaptive optical elements to form a closed-loop control system, continuously optimizing the correction effect until the wavefront error meets the preset threshold requirements.

[0103] Step S7: Repeat steps S2 to S6 until a preset wavefront error threshold is met.

[0104] For example, assume that there is a primary-secondary mirror optical system for astronomical observation, with a primary mirror aperture of 2 meters, a secondary mirror aperture of 0.5 meters, and a focal length of 20 meters. A mathematical model of the optical system is established based on the geometric parameters of the primary and secondary mirrors, such as radius of curvature, aperture, spacing, and optical parameters, such as reflectivity, refractive index, etc.; under the ideal condition that the optical system has no errors, the optical system performance prediction model is used to calculate the ideal wavefront phase distribution of the target light source, such as a star, at the focal plane after passing through the optical system; a high-sensitivity CCD detector is placed at the focal plane of the optical system to collect a point spread function image of the target light source after passing through the optical system. Due to errors in the optical system, the PSF image will be distorted, and an iterative phase recovery algorithm is used to recover the actual wavefront phase distribution of the optical system based on the intensity information of the PSF image; based on the recovered wavefront phase distribution, dynamic adaptive calibration is performed, for example, by real-time monitoring of ambient temperature changes and mirror deformation, adjusting model parameters, and at the same time, feeding back the monitored wavefront phase changes to the primary and secondary mirrors. In the performance prediction model of the optical system, the model parameters are updated to obtain a more accurate performance prediction model and a wavefront phase distribution after dynamic calibration; the wavefront phase distribution after dynamic calibration is compared point by point with the ideal wavefront phase distribution, and the wavefront error is calculated using an adaptive wavefront error compensation algorithm, for example, the root mean square error is calculated, and the trend of the wavefront error changing with temperature is predicted in combination with the updated performance prediction model of the primary and secondary mirror optical system, for example, it is predicted that when the temperature rises by 5°C, the wavefront error will increase by 20%; according to the output results of the adaptive wavefront error compensation algorithm and the prediction of the wavefront error change trend, the wavefront error of the optical system is corrected in real time using an adaptive optical method, for example, a deformable mirror is used to adjust the mirror shape, or the wavefront error is compensated by adjusting the position and posture of the secondary mirror; steps S2 to S6 are repeated to continuously monitor and correct the wavefront error until the wavefront error meets a preset threshold, such as an RMS value less than λ / 20, where λ is the wavelength, for example, after multiple iterations, the wavefront error is reduced from the initial λ / 5 to λ / 25, meeting the requirements of astronomical observations.

[0105] Example 2

[0106] The specific steps of step S2 in this embodiment include:

[0107] S2.1: Determine the wavelength of the target light source and amplitude distribution ,in, Indicates that the target light source is on the initial plane The amplitude distribution on , where and Respectively represent the abscissa and ordinate values ​​of the initial plane;

[0108] S2.2: Based on the established performance prediction model of the primary and secondary mirror optical system, the ray tracing method of geometric optics is used to calculate the propagation path of the light emitted from the target light source to the primary and secondary mirror surfaces;

[0109] S2.3: Continue tracing the light, calculate the propagation path of the light after reflection from the primary and secondary mirrors to the focal plane and the propagation path of the light after reflection to the focal plane, and obtain the coordinates of the intersection of the light on the focal plane ,in, and Respectively represent the horizontal and vertical coordinate values ​​of the intersection point of the light on the focal plane;

[0110] Among them, in the optical system, the focal plane is a specific two-dimensional plane. When considering the phase distribution on the focal plane, its essence is the two-dimensional distribution in the plane. Therefore, the z coordinate is a fixed value. For different points on the focal plane, the phase difference is mainly reflected in the changes in x and y, not z. Therefore, the coordinates of the intersection of the light on the focal plane are expressed as .

[0111] S2.4: For each traced ray, calculate the total optical path from the target light source, through reflection from the primary and secondary mirrors, to any point on the focal plane. ,and , N represents the number of rays emitted by the target light source;

[0112] S2.5: Select a reference light path As a benchmark, the optical path difference of the i-th light relative to the reference light is obtained by difference calculation. ;

[0113] S2.6: Based on the optical path difference , using the relationship between phase and optical path Calculate the phase of each point on the focal plane , where x and y represent the horizontal and vertical coordinate values ​​respectively;

[0114] S2.7: Arrange the calculated phase values ​​of each point on the focal plane into a two-dimensional array to obtain the ideal wavefront phase distribution of the target light source at the focal plane. , and use drawing software to display the ideal wavefront phase distribution in the form of an image.

[0115] See also Figure 3 , the specific steps of S2.2 include:

[0116] S2.21: extracting the parameters of the primary mirror and the secondary mirror from the primary-secondary mirror optical system performance prediction model, wherein the parameters of the primary mirror and the secondary mirror include the curvature radius, the aperture, the spacing between the primary mirror and the secondary mirror, and the vertex position coordinates of the primary and secondary mirrors;

[0117] S2.22: Establishing the light propagation equation ,in, represents the position vector of the light, d represents the distance the light travels from the initial point, represents the initial position vector of the light, represents the direction vector of the light, Represents the position coordinates of the target light source, Indicates the vertical coordinate value of the target light source. Represents the initial emission direction of the light, and satisfies , and The sum of the squares of is equal to 1;

[0118] S2.23: Use the standard spherical equation as the primary mirror equation, substitute the light propagation equation into the primary mirror equation, solve the quadratic equation system, and obtain the coordinates of the intersection of the light and the primary mirror. ,in, , and The horizontal coordinate, the vertical coordinate and the vertical coordinate respectively represent the intersection of the light ray and the primary mirror. In the present invention, the solution formulas of the spherical standard equation and the quadratic equation group are the prior art content in this field, which is not the inventive solution of the present application and will not be described in detail here;

[0119] The standard equation of the sphere is: ,in, represents the spherical center coordinates of the primary mirror, Indicates the radius of curvature of the primary mirror.

[0120] S2.24: Coordinates of the intersection of the light ray and the primary mirror By taking the gradient of the primary mirror equation, we can get the normal vector of the primary mirror surface. ;

[0121] S2.25: According to the law of reflection, the direction vector of the incident light and the normal vector to the primary mirror surface Calculate the direction vector of the reflected light on the primary mirror surface , wherein the reflection law is the prior art content in this field, and is not the inventive solution of this application, and will not be described in detail here;

[0122] S2.26: The coordinates of the intersection of the light ray and the primary mirror As the new starting point, the direction vector of the reflected light from the primary mirror surface As the new direction, update the light propagation equation to ,in, represents the distance the light travels from the reflection point of the primary mirror, represents the coordinates of the intersection of the light ray and the primary mirror, that is, ;

[0123] S2.27: Use the standard spherical equation as the secondary mirror equation, and substitute the updated light propagation equation into the secondary mirror equation to solve the quadratic equation system to obtain the coordinates of the intersection of the light and the secondary mirror. , and calculate the direction vector of the reflected light on the secondary mirror surface according to S2.24-S2.25 ,in, , and They represent the horizontal, vertical and vertical coordinates of the intersection of the light ray and the secondary mirror, respectively, and the standard spherical equation adopts the standard spherical equation in S2.23;

[0124] S2.28: According to and , determine whether the light is on the mirror surface;

[0125] like , then the intersection of the light and the primary mirror is at the aperture of the primary mirror within the scope;

[0126] like , then the intersection of the light and the primary mirror is at the aperture of the secondary mirror within the scope;

[0127] Similarly, because the z coordinate is a constant when judging whether the light is on the mirror surface, it is not considered.

[0128] S2.29: If the intersection of the ray and the primary mirror is within the aperture of the primary mirror The intersection of the light and the primary mirror is within the aperture of the secondary mirror. If it is within the range, it means that the light is on the mirror surface;

[0129] If the light is on the mirror surface, the propagation path of the light from the target light source, reflected by the primary mirror, and then to the secondary mirror is recorded, including the position coordinates of the target light source, the coordinates of the intersection of the light and the primary mirror, the coordinates of the intersection of the light and the secondary mirror, and the corresponding direction vector of the reflected light.

[0130] The specific steps of S2.3 include:

[0131] S2.31: Get the vertex position coordinates of the primary and secondary mirrors, and calculate the distance from the focal plane to the vertex of the primary mirror based on the vertex position coordinates of the primary and secondary mirrors and the distance formula from the point to the plane. , wherein the distance formula from a point to a plane is the prior art content in this field, and is not the inventive solution of the present application, and will not be described in detail here;

[0132] S2.32: Establish the focal plane equation based on the distance from the focal plane to the vertex of the primary mirror ;

[0133] S2.33: Transform the focal plane equation Substituting into the updated expression of the light propagation equation, we get ;

[0134] S2.34: Substitute the calculated d value into the updated light propagation equation to obtain the coordinates of the intersection point of the light on the focal plane .

[0135] The specific steps of S2.4 include:

[0136] S2.41: During ray tracing, based on the position coordinates of the target light source , the coordinates of the intersection of the light and the primary mirror , the coordinates of the intersection of the light ray and the secondary mirror The coordinates of the intersection point with the light on the focal plane , use the distance formula between two points in space to calculate the geometric distance from the target light source to the primary mirror , the geometric distance from the primary mirror to the secondary mirror , the geometric distance from the secondary mirror to the focal plane ;

[0137] Among them, the geometric distance from the target light source to the primary mirror is , the geometric distance from the primary mirror to the secondary mirror , the geometric distance from the secondary mirror to the focal plane ;

[0138] S2.42: By , , Sum and obtain the total optical path of the ith traced ray .

[0139] The specific steps of step S3 include:

[0140] S3.1: Place the detector at the focal plane of the optical system to collect images, and average the collected images to obtain the point spread function image of the target light source after passing through the optical system. ;

[0141] Furthermore, the specific steps of S3.1 include:

[0142] (1) First, build a suitable optical system according to the experimental requirements, ensure that each optical component is installed accurately and the optical path is stable, and use optical measuring instruments with standard light sources to calibrate the optical system. For example, adjust the focal length of the lens and align the optical axis to ensure that the light can be accurately focused on the focal plane.

[0143] (2) The detector is placed on the focal plane of the optical system by means of a mechanical adjustment device, and an optical alignment tool is used to ensure that the photosensitive surface of the detector completely coincides with the focal plane. At the same time, the parameters of the detector are set, including exposure time, gain, and resolution. The detector is a CMOS camera. The exposure time should be reasonably adjusted according to the intensity of the target light source to avoid the image being too bright or too dark.

[0144] (3) Turn on the target light source so that the light it emits passes through the optical system and is focused onto the detector. The detector converts the light signal into an electrical signal or a digital signal to complete the image acquisition.

[0145] (4) The collected images are transferred to a computer and processed using image processing software, mainly by performing numerical averaging calculations on the corresponding pixel points in each image to obtain an averaged image. For example, for the collected image A, the pixel value at the coordinate is the sum of the pixel values ​​of all images at the coordinate divided by A after averaging.

[0146] (5) The image after averaging is the point spread function image of the target light source after it passes through the optical system. The point spread function image reflects the diffusion effect of the optical system on a point light source, which is manifested as the light intensity distribution of the light source on the focal plane.

[0147] S3.2: Setting the initial wavefront phase distribution , combined with the intensity information of the collected point spread function image, construct the initial complex amplitude distribution , where e represents the exponent and j represents the imaginary part;

[0148] S3.3: Distribute the initial complex amplitude Model of forward propagation through an optical system Propagate to a middle plane and obtain the complex amplitude distribution of the middle plane ,in, represents the coordinates of the middle plane, F represents the Fourier transform, represents the inverse Fourier transform, The transfer function representing Fresnel propagation;

[0149] S3.4: In the middle plane, the complex amplitude distribution is adjusted according to the physical constraints of the optical system. Correction is made and the corrected complex amplitude distribution in the middle plane is Through the back propagation model Propagate back to the focal plane to obtain the new focal plane complex amplitude distribution ;

[0150] S3.5: Maintain the new focal plane complex amplitude distribution Phase information , and combined with the intensity information of the collected point spread function image , construct the updated focal plane complex amplitude distribution ;

[0151] S3.6: using the mean square error formula to calculate the difference MSE between the complex amplitude distributions obtained from two adjacent iterations, wherein the mean square error formula is a prior art content in the art, is not an inventive solution of the present application, and is not described in detail here;

[0152] S3.7: Set an error threshold ;

[0153] like , then the updated complex amplitude distribution As the initial value of the next iteration, return to S3.3 to continue the iteration;

[0154] like , the iteration is considered to have converged and the iteration process is terminated;

[0155] S3.8: When the iteration is terminated, the final complex amplitude distribution The phase part That is, the actual wavefront phase distribution of the restored optical system, where ,in, Represents the phase information extraction function of the complex amplitude.

[0156] The specific steps of step S4 include:

[0157] S4.1: Obtain the actual wavefront phase distribution of the restored optical system and performance prediction models for primary and secondary mirror optical systems;

[0158] S4.2: Determine a set of parameters that require dynamic adaptive calibration based on the application requirements and performance indicators of the optical system;

[0159] Furthermore, the specific steps of S4.2 include:

[0160] (1) Clarify the application scenario of the optical system. For example, is it used in astronomical observation, laser communication, or microscopy imaging? Different application scenarios have very different performance requirements for optical systems. For example, astronomical observation may have higher requirements for resolution and light collection capability, while laser communication may focus more on beam pointing accuracy and energy concentration.

[0161] (2) Communicate with the user's experts to determine specific application requirements, such as quantitative indicators such as imaging clarity, target detection distance, and measurement accuracy;

[0162] (3) Convert the overall application requirements into specific optical performance indicators. For example, the image clarity of an imaging system can be measured by resolution, usually expressed as angular resolution or linear resolution; the target detection distance may be related to indicators such as the optical system's luminous flux and signal-to-noise ratio;

[0163] (4) For each performance indicator, determine its acceptable range or specific numerical requirements, for example, an astronomical telescope is required to have an angular resolution of less than 0.1 arc second;

[0164] (5) Study the working principle and structure of the optical system and determine which optical parameters will affect various performance indicators. For example, for a telescope system, the curvature radius, aperture, spacing and other parameters of the primary and secondary mirrors will affect the focal length, aberration, etc. of the system, and thus affect the resolution and imaging quality; the refractive index and dispersion coefficient of the optical material will also have an effect on imaging;

[0165] (6) Establish qualitative and quantitative relationships between performance indicators and optical parameters by consulting optical design manuals. For example, according to the principles of geometric optics and physical optics, resolution is related to the aperture and wavelength of the optical system and can be described by formulas such as the Rayleigh criterion.

[0166] (7) Based on the relationship between performance indicators and optical parameters, select the parameters that play a key role in meeting application requirements and performance indicators. These parameters are the objects that need to be dynamically adaptively calibrated. For example, if the system has high requirements for resolution, then the surface parameters and relative position parameters of the primary and secondary mirrors may need to be dynamically adaptively calibrated.

[0167] (8) Taking into account the actual operability and cost factors, the initially determined parameter set is further optimized to exclude those parameters that are difficult to measure or too costly to adjust, and finally a reasonable parameter set that can achieve dynamic adaptive calibration is determined.

[0168] S4.3: Based on optical theory, establish a mathematical model between calibration parameters and wavefront phase change;

[0169] Furthermore, the specific steps of S4.3 include:

[0170] (1) Analyze the structure of the optical system under study in detail, clarify whether it is refractive, reflective, or catadioptric, and determine the various optical elements involved in the wavefront phase change, such as lenses and mirrors;

[0171] (2) Obtaining parameters that require dynamic adaptive calibration, such as the radius of curvature, thickness, and refractive index of the lens, and the surface parameters, tilt angle, and displacement of the reflector;

[0172] (3) According to the characteristics of the optical system and the operating wavelength range, an optical theory is selected to describe the wavefront propagation and phase change. For example, for large-scale optical elements and macroscopic optical paths in the field of geometric optics, ray tracing and Fermat's principle can be used; for systems involving wave optical phenomena such as diffraction and interference, wave optics theory, such as the Huygens-Fresnel principle and Kirchhoff's diffraction formula, is required. Optical theory is the prior art content in this field and is not the inventive solution of this application, so it is not elaborated here.

[0173] (4) Analyze the propagation path and changes of the wavefront in the optical system based on the selected optical theory. For example, in the ray tracing method, calculate the angle of incidence, refraction and reflection of the light on the surface of each optical element to determine the propagation direction and position change of the light. In wave optics, consider the diffraction and interference effects of the wavefront when passing through an aperture, obstacle or optical element, and analyze the phase and amplitude changes of the wavefront.

[0174] (5) Based on the wavefront propagation analysis, a quantitative relationship is established between the calibration parameters and the wavefront phase change. Taking the lens as an example, according to the imaging formula of the lens and the phase delay principle, a mathematical expression between the lens parameters such as the radius of curvature and thickness and the wavefront phase delay is established; for the reflector, according to the law of reflection and the surface shape equation of the mirror, a relationship between the surface shape parameters, tilt angle, etc. of the reflector and the wavefront phase change is established. Among them, the imaging formula of the lens, the phase delay principle, the law of reflection and the surface shape equation of the mirror are all prior art contents in this field, and are not the inventive solution of the present application, and will not be elaborated here;

[0175] (6) Verify the established mathematical model through experimental measurements or known standard data, and compare the model calculation results with the actual measured wavefront phase change to analyze the source of error;

[0176] (7) Based on the verification results, the mathematical model is optimized and adjusted, such as considering more optical effects, correcting the parameter value range, etc., to improve the accuracy and reliability of the model.

[0177] S4.4: Using the optical adjustment device, adjust the primary and secondary mirrors according to the preset calibration strategy, monitor the change of the wavefront phase in real time, and record the initial data;

[0178] S4.5: At time intervals Collect wavefront phase data and compare the real-time monitored wavefront phase change with the expected wavefront phase change to obtain the wavefront phase difference , according to the wavefront phase difference, the feedback amount that needs to be fed back to the primary and secondary mirror optical system performance prediction model is calculated through the PID control algorithm, where: represents the wavefront phase distribution monitored in real time, It represents the expected wavefront phase distribution, and the PID control algorithm is the prior art content in this field, which is not the inventive solution of the present application and will not be described in detail here;

[0179] S4.6: According to the feedback, the parameters of the primary and secondary mirror optical system performance prediction model are updated, and the updated primary and secondary mirror optical system performance prediction model is recalculated and generated using the updated parameters, and the wavefront phase distribution after dynamic calibration is recorded at the same time .

[0180] The specific steps of step S5 include:

[0181] S5.1: Obtaining the wavefront phase distribution after dynamic calibration and the updated performance prediction model of the primary and secondary mirror optical system, and set the ideal wavefront phase distribution ;

[0182] S5.2: For each coordinate point on the focal plane , the wavefront phase distribution after dynamic calibration Compared with the ideal wavefront phase distribution Compare and calculate the difference to obtain the wavefront error , and the calculated wavefront error Conduct mean analysis;

[0183] S5.3: Combine the updated performance prediction model of the primary and secondary mirror optical system with the wavefront error information As input parameters, the optical propagation and transformation relations in the updated performance prediction model of the primary and secondary mirror optical system are used to predict the changing trend of the wavefront error under different time changes.

[0184] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in the field may also change, modify, replace and modify the above-mentioned embodiments without departing from the purpose and scope of protection of the present invention, and all of these are within the protection of the present invention.

Claims

1. A wavefront error detection method for a primary and secondary mirror optical system, characterized in that: include: Step S1: Establishing a performance prediction model for the primary and secondary mirror optical system; Step S2: Based on the established performance prediction model of the primary and secondary mirror optical system, under the ideal condition that the optical system has no errors, the ideal wavefront phase distribution of the target light source at the focal plane after passing through the optical system is calculated; Step S3: placing a detector at the focal plane of the optical system, collecting a point spread function image of the target light source after passing through the optical system, and using an iterative phase recovery algorithm to recover the actual wavefront phase distribution of the optical system according to the intensity information of the point spread function image; Step S4: Based on the restored wavefront phase distribution, dynamic adaptive calibration is performed, and at the same time, the change of the wavefront phase is monitored in real time, and the change is fed back to the primary and secondary mirror optical system performance prediction model for updating, so as to obtain the updated primary and secondary mirror optical system performance prediction model and the wavefront phase distribution after dynamic calibration; Step S5: comparing the dynamically calibrated wavefront phase distribution with the ideal wavefront phase distribution point by point, calculating the wavefront error, and predicting the wavefront error change trend in combination with the updated primary and secondary mirror optical system performance prediction model; Step S6: Correcting the wavefront error of the optical system in real time according to the wavefront error and the prediction of the wavefront error change trend; Step S7: Repeat steps S2 to S6 until a preset wavefront error threshold is met.

2. A wavefront error detection method for a primary-secondary mirror optical system as claimed in claim 1, characterized in that: The specific steps of step S2 include: S2.1: Determine the wavelength of the target light source and amplitude distribution ,in, Indicates that the target light source is on the initial plane The amplitude distribution on , where and Respectively represent the abscissa and ordinate values ​​of the initial plane; S2.2: Based on the established performance prediction model of the primary and secondary mirror optical system, the ray tracing method of geometric optics is used to calculate the propagation path of the light emitted from the target light source to the primary and secondary mirror surfaces; S2.3: Continue tracing the light, calculate the propagation path of the light after reflection from the primary and secondary mirrors to the focal plane and the propagation path of the light after reflection to the focal plane, and obtain the coordinates of the intersection of the light on the focal plane ,in, and Respectively represent the horizontal and vertical coordinate values ​​of the intersection point of the light on the focal plane; S2.4: For each traced ray, calculate the total optical path from the target light source, through reflection from the primary and secondary mirrors, to any point on the focal plane. ,and , N represents the number of rays emitted by the target light source; S2.5: Select a reference light path As a benchmark, the optical path difference of the i-th light relative to the reference light is obtained by difference calculation. ; S2.6: Based on the optical path difference , using the relationship between phase and optical path to calculate the phase of each point on the focal plane , where x and y represent the horizontal and vertical coordinate values ​​respectively; S2.7: Arrange the calculated phase values ​​of each point on the focal plane into a two-dimensional array to obtain the ideal wavefront phase distribution of the target light source at the focal plane. , and use drawing software to display the ideal wavefront phase distribution in the form of an image.

3. A wavefront error detection method for a primary-secondary mirror optical system as claimed in claim 2, characterized in that: The specific steps of S2.2 include: S2.21: extracting the parameters of the primary mirror and the secondary mirror from the primary-secondary mirror optical system performance prediction model, wherein the parameters of the primary mirror and the secondary mirror include the curvature radius, the aperture, the spacing between the primary mirror and the secondary mirror, and the vertex position coordinates of the primary and secondary mirrors; S2.22: Based on the property that light travels in a straight line in a homogeneous medium, establish the light propagation equation ,in, represents the position vector of the light, d represents the distance the light travels from the initial point, represents the initial position vector of the light, represents the direction vector of the light, Represents the position coordinates of the target light source, Indicates the vertical coordinate value of the target light source. Indicates the initial emission direction of the light; S2.23: Use the standard spherical equation as the primary mirror equation, substitute the light propagation equation into the primary mirror equation, solve the quadratic equation system, and obtain the coordinates of the intersection of the light and the primary mirror. ,in, , and Respectively represent the horizontal, vertical and vertical coordinate values ​​of the intersection point of the light ray with the primary mirror; S2.24: Coordinates of the intersection of the light ray and the primary mirror By taking the gradient of the primary mirror equation, we can get the normal vector of the primary mirror surface. ; S2.25: According to the law of reflection, the direction vector of the incident light and the normal vector to the primary mirror surface Calculate the direction vector of the reflected light on the primary mirror surface ; S2.26: The coordinates of the intersection of the light ray and the primary mirror As the new starting point, the direction vector of the reflected light from the primary mirror surface As the new direction, update the light propagation equation to ,in, represents the distance the light travels from the reflection point of the primary mirror, represents the coordinates of the intersection of the light ray and the primary mirror, that is, .

4. A wavefront error detection method for a primary-secondary mirror optical system as claimed in claim 3, characterized in that: The specific steps of S2.2 also include: S2.27: Use the standard spherical equation as the secondary mirror equation, and substitute the updated light propagation equation into the secondary mirror equation to solve the quadratic equation system to obtain the coordinates of the intersection of the light and the secondary mirror. , and calculate the direction vector of the reflected light on the secondary mirror surface according to S2.24-S2.25 ,in, , and Respectively represent the horizontal, vertical and vertical coordinate values ​​of the intersection point of the light ray with the secondary mirror; S2.28: According to and , determine whether the light is on the mirror surface; like , then the intersection of the light and the primary mirror is at the aperture of the primary mirror within the scope; like , then the intersection of the light and the primary mirror is at the aperture of the secondary mirror within the scope; S2.29: If the intersection of the ray and the primary mirror is within the aperture of the primary mirror The intersection of the light and the primary mirror is within the aperture of the secondary mirror. If it is within the range, it means that the light is on the mirror surface; If the light is on the mirror surface, the propagation path of the light from the target light source, reflected by the primary mirror, and then to the secondary mirror is recorded, including the position coordinates of the target light source, the coordinates of the intersection of the light and the primary mirror, the coordinates of the intersection of the light and the secondary mirror, and the corresponding direction vector of the reflected light.

5. A wavefront error detection method for a primary-secondary mirror optical system as claimed in claim 4, characterized in that: The specific steps of S2.3 include: S2.31: Get the vertex position coordinates of the primary and secondary mirrors, and calculate the distance from the focal plane to the vertex of the primary mirror based on the vertex position coordinates of the primary and secondary mirrors and the distance formula from the point to the plane. ; S2.32: Establish the focal plane equation based on the distance from the focal plane to the vertex of the primary mirror ; S2.33: Transform the focal plane equation Substituting into the updated expression of the light propagation equation, we get ; S2.34: Substitute the calculated d value into the updated light propagation equation to obtain the coordinates of the intersection point of the light on the focal plane .

6. A wavefront error detection method for a primary-secondary mirror optical system as claimed in claim 5, characterized in that: The specific steps of S2.4 include: S2.41: During ray tracing, based on the position coordinates of the target light source , the coordinates of the intersection of the light and the primary mirror , the coordinates of the intersection of the light ray and the secondary mirror The coordinates of the intersection point with the light on the focal plane , use the distance formula between two points in space to calculate the geometric distance from the target light source to the primary mirror , the geometric distance from the primary mirror to the secondary mirror , the geometric distance from the secondary mirror to the focal plane ; S2.42: By , , Sum and obtain the total optical path of the ith traced ray .

7. A wavefront error detection method for a primary-secondary mirror optical system as claimed in claim 6, characterized in that: The specific steps of step S3 include: S3.1: Place the detector at the focal plane of the optical system to collect images, and average the collected images to obtain the point spread function image of the target light source after passing through the optical system. ; S3.2: Setting the initial wavefront phase distribution , combined with the intensity information of the collected point spread function image, construct the initial complex amplitude distribution ; S3.3: Distribute the initial complex amplitude The forward propagation model of the optical system propagates to an intermediate plane and obtains the complex amplitude distribution of the intermediate plane. ,in, represents the coordinates of the middle plane; S3.4: In the middle plane, the complex amplitude distribution is adjusted according to the physical constraints of the optical system. Correction is made and the corrected complex amplitude distribution in the middle plane is Propagate back to the focal plane through the back propagation model to obtain the new focal plane complex amplitude distribution .

8. A wavefront error detection method for a primary-secondary mirror optical system as claimed in claim 7, characterized in that: The specific steps of step S3 also include: S3.5: Maintain the new focal plane complex amplitude distribution Phase information , and combined with the intensity information of the collected point spread function image , construct the updated focal plane complex amplitude distribution ; S3.6: Use the mean square error formula to calculate the difference MSE between the complex amplitude distributions obtained from two adjacent iterations; S3.7: Set an error threshold ; like , then the updated complex amplitude distribution As the initial value of the next iteration, return to S3.3 to continue the iteration; like , the iteration is considered to have converged and the iteration process is terminated; S3.8: When the iteration is terminated, the final complex amplitude distribution The phase part That is the restored actual wavefront phase distribution of the optical system.

9. A wavefront error detection method for a primary-secondary mirror optical system as claimed in claim 8, characterized in that: The specific steps of step S4 include: S4.1: Obtain the actual wavefront phase distribution of the restored optical system and performance prediction models for primary and secondary mirror optical systems; S4.2: Determine a set of parameters that require dynamic adaptive calibration based on the application requirements and performance indicators of the optical system; S4.3: Based on optical theory, establish a mathematical model between calibration parameters and wavefront phase change; S4.4: Using the optical adjustment device, adjust the primary and secondary mirrors according to the preset calibration strategy, monitor the change of the wavefront phase in real time, and record the initial data; S4.5: At time intervals Collect wavefront phase data and compare the real-time monitored wavefront phase change with the expected wavefront phase change to obtain the wavefront phase difference , according to the wavefront phase difference value, the feedback amount that needs to be fed back to the performance prediction model of the primary and secondary mirror optical systems is calculated through the PID control algorithm; S4.6: According to the feedback, the parameters of the primary and secondary mirror optical system performance prediction model are updated, and the updated primary and secondary mirror optical system performance prediction model is recalculated and generated using the updated parameters, and the wavefront phase distribution after dynamic calibration is recorded at the same time .

10. A wavefront error detection method for a primary-secondary mirror optical system as claimed in claim 9, characterized in that: The specific steps of step S5 include: S5.1: Obtaining the wavefront phase distribution after dynamic calibration and the updated performance prediction model of the primary and secondary mirror optical system, and set the ideal wavefront phase distribution ; S5.2: For each coordinate point on the focal plane , the wavefront phase distribution after dynamic calibration Compared with the ideal wavefront phase distribution Compare and calculate the difference to obtain the wavefront error , and the calculated wavefront error Conduct mean analysis; S5.3: Combine the updated performance prediction model of the primary and secondary mirror optical system with the wavefront error information As input parameters, the optical propagation and transformation relations in the updated performance prediction model of the primary and secondary mirror optical system are used to predict the changing trend of the wavefront error under different time changes.

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