Method and device for reconstructing maladjustment aberration in complex cylindrical surface pseudo-shear interference detection

Abstract

The invention discloses a detuning aberration reconstruction method and device in complex cylindrical surface pseudo-shear interference detection, and the method comprises the steps: firstly obtaining first wavefront data of a cylindrical mirror to be detected, which is measured by an interferometer, and second wavefront data detected by the interferometer after the cylindrical mirror to be detected moves once in the curvature direction when interference fringes are zeroed; the third wavefront data is detected by the interferometer after the cylindrical mirror to be detected moves once again along the curvature direction; the method comprises the following steps of: firstly, obtaining first-order differential data without maladjustment aberration by using the three wavefront data, then obtaining second-order differential data without maladjustment aberration by using the three wavefront data, then generating first-order differential maladjustment aberration-free wavefront data by using the second-order differential data, and finally obtaining maladjustment aberration generated by the cylindrical mirror to be measured moving along the curvature direction based on the first-order differential maladjustment aberration-free wavefront data. Thus, by reconstructing the maladjustment aberration, the accuracy of the differential wavefront data used when the cylindrical surface shape is reconstructed can be ensured, and the reconstruction precision of the cylindrical surface shape error is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of optical precision measurement, and in particular to a method and device for reconstructing misalignment aberration in complex cylindrical pseudo-shearing interferometry detection. Background Art

[0002] Cylindrical mirrors have the geometric optical property that the radius of curvature in one direction is infinite and the radius of curvature in the other direction is finite. They are often used for line focusing or correcting aberrations. Among them, cylindrical mirrors are optical components widely used in high-precision instruments, and their surface quality has high precision requirements. Therefore, high requirements are also placed on the processing and detection technology of cylindrical mirrors.

[0003] In modern optical precision machining, more and more shaping processes are adopted based on surface errors. Therefore, detection accuracy is of vital importance. Interference method has become the main means of detecting complex cylindrical optical components due to its high precision. At present, there are mainly zero-position interference method and non-zero-position interference method for interference detection of complex cylindrical surfaces. Among them, for the zero-position interference method, a high-precision compensation mirror that matches the surface shape of the cylindrical mirror to be measured is required. This method has high accuracy but lacks versatility. The non-zero-position interference detection method has lower requirements for the compensation mirror and mainly uses algorithms to compensate for the impact of insufficient accuracy of the compensation mirror. It has high versatility, but will introduce some additional errors.

[0004] Currently, the prior art CN117889780A proposes a non-zero-position interferometric measurement device and method for an off-axis aspheric cylindrical mirror, which achieves high-precision measurement of an off-axis aspheric cylindrical surface. However, when the cylindrical mirror is moved along the curvature direction, misalignment aberrations are still generated due to the change in the sag height (i.e., the change in the curvature radius) of the cylindrical mirror. Although the misalignment aberrations can be reduced by zeroing the interference fringes and performing precise movement during measurement, this method is subject to various limitations and cannot completely eliminate the misalignment aberrations. This results in inaccurate differential wavefront data in the two orthogonal directions used to reconstruct the cylindrical surface shape, thereby affecting the reconstruction accuracy of the cylindrical mirror surface shape error. Therefore, based on the aforementioned deficiencies, how to provide a misalignment aberration reconstruction method that can reconstruct the misalignment aberration caused by the movement of the cylindrical mirror along the curvature direction, thereby improving the reconstruction accuracy of the cylindrical mirror surface shape error, has become an urgent problem to be solved. Summary of the Invention

[0005] The technical problem to be solved by the present invention is the problem of measuring the surface shape error of a complex cylindrical mirror. The purpose is to provide a method and device for reconstructing the misalignment aberration in the pseudo-shearing interferometry detection of a complex cylindrical surface, which solves the problem in traditional technology that the misalignment aberration is introduced by moving the cylindrical mirror along the curvature direction, resulting in inaccurate two differential wavefront data in the orthogonal directions used when reconstructing the cylindrical surface shape, thereby affecting the reconstruction accuracy of the cylindrical mirror surface shape error.

[0006] The present invention is achieved through the following technical solutions: In a first aspect, a method for reconstructing misalignment aberration in complex cylindrical pseudo-shearing interferometry detection is provided, comprising: Acquiring first wavefront data of the cylindrical mirror to be measured detected by the complex cylindrical interference detection system when the interference fringes are zeroed, and controlling the cylindrical mirror to be measured in the complex cylindrical interference detection system to move along the direction of curvature, so as to obtain second wavefront data and third wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves along the direction of curvature, wherein the second wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the direction of curvature, and the third wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the direction of curvature; Based on the first wavefront data, the second wavefront data and the third wavefront data, and using the pseudo shearing method, the second-order differential wavefront data of the cylindrical lens to be tested is constructed to eliminate the misalignment aberration; A time-frequency domain conversion algorithm is used to establish a second-order differential frequency domain data conversion formula between the second-order differential wavefront data that eliminates the misalignment aberration and the first-order differential wavefront data of the cylindrical lens to be tested, so as to perform unidirectional reconstruction on the second-order differential frequency domain data conversion formula. A smoothing factor is added during the unidirectional reconstruction process to smooth the fringe noise generated by the unidirectional reconstruction, thereby obtaining the first-order differential wavefront data without misalignment aberration corresponding to the cylindrical lens to be tested. The measured first-order difference data of the cylindrical mirror to be tested is obtained, and the measured first-order difference data is subtracted from the first-order difference non-misalignment aberration wavefront data to reconstruct the misalignment aberration caused by the movement of the cylindrical mirror to be tested along the curvature direction, so as to determine the surface error of the cylindrical mirror to be tested based on the misalignment aberration.

[0007] Based on the above-disclosed content, the present invention first obtains the first wavefront data of the cylindrical mirror to be measured by the interferometer in the complex cylindrical interference detection system when the interference fringes are zeroed, and then moves the cylindrical mirror to be measured along the curvature direction (without making other posture adjustments), that is, moves the cylindrical mirror to be measured once along the curvature direction to obtain the second wavefront data detected by the interferometer, and then, based on the above-mentioned movement, moves it once again to obtain the third wavefront data detected by the interferometer; then, the present invention uses the above-mentioned three wavefront data to construct the second-order differential wavefront data of the cylindrical mirror to be measured to eliminate the misalignment aberration; then, based on the unidirectional reconstruction idea and using the time-frequency domain method, a second-order differential frequency domain data conversion formula between the second-order differential wavefront data and the first-order differential wavefront data is established to perform unidirectional reconstruction on it, and at the same time, During the reconstruction process, a smoothing factor is added to smooth the stripes along the integral direction generated by the unidirectional reconstruction, thereby obtaining the first-order differential wavefront data without misalignment aberration corresponding to the cylindrical mirror to be measured; then, the measured first-order differential data of the cylindrical mirror to be measured is subtracted from the aforementioned first-order differential wavefront data without misalignment aberration, thereby reconstructing the misalignment aberration generated by the movement of the cylindrical mirror to be measured along the curvature direction; finally, the aforementioned misalignment aberration is used to determine the surface error of the cylindrical mirror to be measured (that is, based on the reconstructed misalignment aberration, two differential wavefront data without misalignment aberration in orthogonal directions are obtained, and the surface error of the cylindrical mirror to be measured is reconstructed thereby); in this way, the present invention can ensure the accuracy of the differential wavefront data used in reconstructing the cylindrical surface shape by reconstructing the misalignment aberration, thereby improving the reconstruction accuracy of the cylindrical mirror surface error.

[0008] In a possible design, the cylindrical mirror to be tested generates the misalignment aberration only when it moves along the curvature direction, and the moving distance of the cylindrical mirror to be tested is the same each time it moves along the curvature direction; Among them, the first wavefront data of the cylindrical mirror to be tested detected by the complex cylindrical interferometry detection system is:

[0009] Where, represents the first wavefront data, The following table represents the surface error distribution of the cylindrical mirror to be measured, the system error of the complex cylindrical interferometry detection system, the surface error distribution of the compensation mirror in the complex cylindrical interferometry detection system, and the return error introduced by the non-zero position detection, where x and y represent the coordinate axes of the complex cylindrical interferometry detection system, the x-axis is the curvature direction of the cylindrical mirror to be measured, and the y-axis is the non-curvature direction; After the cylindrical mirror to be tested moves once along the curvature direction, the second wavefront data detected by the complex cylindrical interferometry detection system is:

[0010] Where, represents the second wave front data, It indicates the surface shape distribution error corresponding to the cylindrical mirror to be measured after it moves once along the curvature direction. Indicates the distance that the cylindrical mirror to be tested moves once along the curvature direction. It indicates the misalignment aberration caused by the cylindrical lens to be tested moving once along the curvature direction; Correspondingly, after the cylindrical mirror to be tested moves once along the curvature direction and then moves once again, the third wavefront data detected by the complex cylindrical interferometry detection system is:

[0011] Where, represents the third wave front data, It indicates the surface shape distribution error of the cylindrical mirror to be measured after it moves once along the curvature direction and then moves again.

[0012] In a possible design, based on the first wavefront data, the second wavefront data, and the third wavefront data, and using the pseudo-shearing method, the second-order differential wavefront data of the cylindrical lens to be tested is constructed to eliminate the misalignment aberration, including: calculating a difference between the second wavefront data and the first wavefront data to obtain first differential wavefront data, and calculating a difference between the third wavefront data and the second wavefront data to obtain second differential wavefront data; The first differential wavefront data and the second differential wavefront data are respectively:

[0013]

[0014] Where, represents the first differential wavefront data, represents the second differential wavefront data; Subtracting the first differential wavefront data from the second differential wavefront data to obtain the second-order differential wavefront data; Wherein, the second-order differential wavefront data is:

[0015] Where, represents the second-order difference wavefront data.

[0016] In one possible design, the second-order differential wavefront data is constructed based on the first-order differential wavefront data of the cylindrical lens to be tested, wherein the first-order differential wavefront data includes first differential wavefront data and second differential wavefront data, and the first differential wavefront data is the difference between the second wavefront data and the first wavefront data, and the second differential wavefront data is the difference between the third wavefront data and the second wavefront data; Among them, a time-frequency domain conversion algorithm is used to establish a second-order differential frequency domain data conversion formula between the second-order differential wavefront data that eliminates the misalignment aberration and the first-order differential wavefront data of the cylindrical lens to be tested, so as to perform unidirectional reconstruction on the second-order differential frequency domain data conversion formula. A smoothing factor is added in the unidirectional reconstruction process to smooth the fringe noise generated by the unidirectional reconstruction, and the first-order differential wavefront data without misalignment aberration corresponding to the cylindrical lens to be tested is obtained, including: performing conversion processing on the second-order differential wavefront data so as to use the first differential wavefront data to represent second differential wavefront data in the second-order differential wavefront data, thereby obtaining converted second-order differential wavefront data; Performing Fourier transform processing on the converted second-order differential wavefront data to obtain the second-order differential frequency domain data conversion formula; Based on the smoothing factor, the second-order differential frequency domain data conversion formula is regularized to obtain regularized differential frequency domain data; The regularized differential frequency domain data is subjected to inverse Fourier transform processing to reconstruct the first-order differential non-misaligned aberration wavefront data after the inverse Fourier transform processing.

[0017] In one possible design, the converted second-order difference wavefront data is:

[0018] Where, represents the number of second-order difference wavefronts after conversion, represents the first differential wavefront data, represents the second differential wavefront data, representing second differential wavefront data represented using the first differential wavefront data; Correspondingly, the second-order differential frequency domain data conversion formula is:

[0019] Where, Represents the second-order differential frequency domain data conversion formula, represents the Fourier transform, express The corresponding frequency domain data, express The corresponding frequency domain data, represents the frequency coordinate in two-dimensional Fourier space, It represents the moving distance corresponding to one movement of the cylindrical mirror to be tested along the curvature direction. Represents an imaginary unit.

[0020] In a possible design, the second-order difference frequency domain data transformation formula is regularized based on the smoothing factor to obtain regularized difference frequency domain data, including: Based on the smoothing factor and using the following formula, the second-order differential frequency domain data conversion formula is regularized to obtain the regularized differential frequency domain data;

[0021] Where, represents the regularized difference frequency domain data, Represents the second-order differential frequency domain data conversion formula, represents the frequency coordinate in two-dimensional Fourier space, represents the smoothing factor, , represents the intermediate parameters, represents the complex conjugate symbol, where ,and It represents the moving distance corresponding to one movement of the cylindrical mirror to be tested along the curvature direction. Represents an imaginary unit.

[0022] In one possible design, the first-order difference aberration-free wavefront data is:

[0023] In the above formula, represents the first-order difference non-misaligned aberration wavefront data, represents the inverse Fourier transform, It indicates the surface shape distribution error corresponding to the cylindrical mirror to be measured after it moves once along the curvature direction. Indicates the surface error distribution of the cylindrical mirror to be measured.

[0024] In one possible design, first differential wavefront data obtained by subtracting the first wavefront data from the second wavefront data is used as the measured first-order differential data; Among them, the misalignment aberration caused by the reconstructed movement of the cylindrical mirror to be tested along the curvature direction is:

[0025] Where, represents the misalignment aberration, represents the first-order difference non-misaligned aberration wavefront data, represents the measured first-order difference data; Correspondingly, determining the surface error of the cylindrical mirror to be measured based on the misalignment aberration includes: Acquire measured differential wavefront data obtained by moving the cylindrical mirror to be measured along the orthogonal direction; subtracting the misalignment aberration from the measured differential wavefront data to obtain ideal differential wavefront data; Based on the ideal differential wavefront data and using a wave surface integral restoration algorithm, the surface shape error of the cylindrical mirror to be measured is obtained.

[0026] In a second aspect, a device for reconstructing misalignment aberration in complex cylindrical pseudo-shearing interferometry detection is provided, comprising: a detection unit, configured to obtain first wavefront data of the cylindrical mirror to be measured detected by the complex cylindrical interference detection system when the interference fringes are zeroed, and to control the cylindrical mirror to be measured in the complex cylindrical interference detection system to move along the direction of curvature, so as to obtain second and third wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves along the direction of curvature, wherein the second wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the direction of curvature, and the third wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the direction of curvature; A second-order difference unit is used to construct second-order difference wavefront data for eliminating misalignment aberration of the cylindrical lens to be tested based on the first wavefront data, the second wavefront data and the third wavefront data and using a pseudo-shearing method; a misalignment aberration reconstruction unit, configured to use a time-frequency domain conversion algorithm to establish a second-order differential frequency domain data conversion formula between the second-order differential wavefront data that eliminates misalignment aberrations and the first-order differential wavefront data of the cylindrical lens to be tested, so as to perform unidirectional reconstruction of the second-order differential frequency domain data conversion formula, and to add a smoothing factor during the unidirectional reconstruction process to smooth the fringe noise generated by the unidirectional reconstruction, thereby obtaining the first-order differential wavefront data without misalignment aberrations corresponding to the cylindrical lens to be tested; The misalignment aberration reconstruction unit is further used to obtain the measured first-order difference data of the cylindrical mirror to be tested, and subtract the measured first-order difference data from the first-order difference wavefront data without misalignment aberration to reconstruct the misalignment aberration caused by the movement of the cylindrical mirror to be tested along the curvature direction, so as to determine the surface error of the cylindrical mirror to be tested based on the misalignment aberration.

[0027] In the third aspect, another misalignment aberration reconstruction device in complex cylindrical pseudo-shearing interferometry detection is provided. Taking the device as an electronic device as an example, it includes a memory, a processor and a transceiver that are communicatively connected in sequence, wherein the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the misalignment aberration reconstruction method in complex cylindrical pseudo-shearing interferometry detection as described in the first aspect or any possible design of the first aspect.

[0028] Compared with the prior art, the present invention has the following advantages and beneficial effects: (1) The application first obtains first wavefront data of a to-be-measured cylindrical mirror measured by an interferometer in a cylindrical interferometric detection system when the interference fringes are zeroed, second wavefront data detected by the interferometer after the to-be-measured cylindrical mirror moves once along the curvature direction, and third wavefront data detected by the interferometer after the to-be-measured cylindrical mirror moves again along the curvature direction; then, the aforementioned three wavefront data are used to obtain second-order difference data without misalignment aberration, then the aforementioned second-order difference data are used to generate first-order difference misalignment aberration-free wavefront data, finally, the measured first-order difference data is subtracted from the aforementioned first-order difference misalignment aberration-free wavefront data, and then misalignment aberration generated by movement of the to-be-measured cylindrical mirror along the curvature direction can be reconstructed; in this way, the accuracy of difference wavefront data used in the reconstruction of the cylindrical surface shape is ensured by reconstructing the misalignment aberration, and the reconstruction precision of the cylindrical mirror surface shape error is improved. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the example embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be considered as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor. In the drawings: Figure 1 The flow chart of the misalignment aberration reconstruction method in the complex cylindrical pseudo-shearing interferometric detection provided by the embodiments of the present application; Figure 2 The structural schematic diagram of the complex cylindrical interferometric detection system provided by the embodiments of the present application; Figure 3 The reconstruction result graph of the misalignment aberration introduced in the pseudo-shearing interferometric detection of the complex cylindrical mirror provided by the embodiments of the present application; Figure 4 The structural diagram of the misalignment aberration reconstruction device in the complex cylindrical pseudo-shearing interferometric detection provided by the embodiments of the present application; Figure 5 The structural schematic diagram of the electronic device provided by the embodiments of the present application.

[0030] Reference signs: 1-interferometer; 2-standard plane wave lens; 3-to-be-measured cylindrical mirror; 5-cylindrical mirror clamping and adjusting mechanism; 6-displacement mechanism; 7-compensation mirror; 8-compensation mirror clamping and adjusting mechanism; 9-reflective standard mirror; 10-reflective mirror clamping and adjusting mechanism. DETAILED DESCRIPTION

[0031] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the following examples and accompanying drawings. The exemplary embodiments of the present invention and their descriptions are intended only to explain the present invention and are not intended to limit the present invention. It should be understood that although the terms "first," "second," and so on may be used herein to describe various elements, these elements should not be limited by these terms. These terms are merely used to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element without departing from the scope of the exemplary embodiments of the present invention.

[0032] Example: See also Figure 1 As shown, the misalignment aberration reconstruction method in the complex cylindrical pseudo-shearing interferometry detection provided by this embodiment determines the second-order difference data without misalignment aberration by obtaining the first wavefront data of the cylindrical mirror to be tested measured by the interferometer in the complex cylindrical interferometry detection system when the interference fringes are zeroed, the second wavefront data detected by the interferometer after the cylindrical mirror to be tested moves a preset distance along the curvature direction, and the third wavefront data detected by the interferometer after the cylindrical mirror to be tested moves a preset distance along the curvature direction again. Then, the first-order difference data is generated by using the above-mentioned second-order difference data based on the unidirectional reconstruction concept and the time-frequency domain conversion algorithm. The misalignment-free wavefront data is obtained by subtracting the measured first-order difference data from the first-order difference wavefront data without misalignment, and then the misalignment aberration caused by the movement of the cylindrical mirror to be measured along the curvature direction can be obtained; in this way, by reconstructing the misalignment aberration, the accuracy of the differential wavefront data used in reconstructing the cylindrical surface shape can be guaranteed, thereby improving the reconstruction accuracy of the cylindrical mirror surface shape error; among them, for example, this method can be but is not limited to running on the computer or server side. It can be understood that the aforementioned execution subject does not constitute a limitation on the embodiments of the present application. Accordingly, the operation steps of this method can be but are not limited to the following steps S1 to S4.

[0033] S1. Obtain the first wavefront data of the cylindrical mirror to be measured detected by the complex cylindrical interference detection system when the interference fringes are zeroed, and control the cylindrical mirror to be measured in the complex cylindrical interference detection system to move along the curvature direction, so as to obtain the second wavefront data and the third wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves along the curvature direction, wherein the second wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the curvature direction, and the third wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the curvature direction; in this embodiment, for example, the moving distance when the aforementioned cylindrical mirror to be measured moves once along the curvature direction can be, but is not limited to, set to 0.4 mm, wherein the moving distance is related to the spatial resolution of the interferometer in the complex cylindrical interference detection system, and the moving distance of the cylindrical mirror to be measured is the same each time it moves along the curvature direction.

[0034] In a specific implementation, the detailed structure of the complex cylindrical interference detection system constructed above is disclosed below, which may include but is not limited to: an interferometer module, a cylindrical mirror module to be measured, a compensation mirror module, and a reflection standard mirror module; wherein the interferometer module includes an interferometer 1 and a standard plane wave lens 2, the cylindrical mirror module to be measured includes a cylindrical mirror to be measured 3, a cylindrical mirror clamping and adjustment mechanism 5, and a displacement mechanism 6 (the cylindrical mirror clamping and adjustment mechanism 5 is mounted with the cylindrical mirror 3 to be measured, and the displacement mechanism 6 is used to move the entire cylindrical mirror clamping and adjustment mechanism 5 to achieve the movement of the cylindrical mirror 3 to be measured), the compensation mirror module includes a compensation mirror 7 and a compensation mirror clamping and adjustment mechanism 8, and the reflection standard mirror module includes a reflection standard mirror 9 and a reflection mirror clamping and adjustment mechanism 10, wherein the arrangement structure of each of the aforementioned components can be seen in FIG. Figure 2 shown.

[0035] The working process of the aforementioned complex cylindrical interference detection system is as follows: the interferometer 1 generates a beam of parallel light, a part of the parallel light is reflected by the standard plane wave lens 2 inside the interferometer 1 to form a reference beam, and the remaining part of the light passes through the standard plane wave lens 2 and is incident on the cylindrical mirror 3 to be measured, and then is reflected by the cylindrical mirror 3 to be measured to the compensation mirror 7, and then, after being reflected again, it is re-formed into parallel light and is incident on the reflective standard mirror 9, and after being reflected by it, it returns to the interferometer 1 along the original path to form a test beam; in this way, the interference between the reference beam and the test beam generates a surface shape error of the surface to be measured; based on this, by controlling the displacement mechanism 6 to move the cylindrical mirror 3 to be measured multiple times along the curvature direction, different spatial positions (for example Figure 2 The surface shape error at the position indicated by mark 4 in the figure.

[0036] In specific applications, when the cylindrical mirror to be tested moves along the curvature direction in the aforementioned complex cylindrical interferometry detection system, the sag height changes significantly (i.e., the curvature radius changes significantly), which will produce misalignment aberration, causing an additional 45° astigmatism to be added to the interferometer's detection results ( ), Defocus( ), Coma ( ) and other aberrations, the misalignment aberration introduced is superimposed on the original surface shape of the cylinder, which will cause the two differential wavefront data in the orthogonal directions to be inaccurate, and thus cause the reconstructed cylindrical surface shape to be inaccurate; therefore, this embodiment reconstructs the misalignment error generated when moving along the curvature direction to obtain accurate two differential wavefront data in the orthogonal directions, thereby improving the accuracy of surface shape reconstruction.

[0037] In a specific implementation, since the misalignment aberration will not be generated when the cylindrical mirror to be tested is moved in a non-curvature direction, that is, the misalignment aberration will only be generated when the cylindrical mirror to be tested is moved in the curvature direction, this embodiment only considers the curvature direction, that is, first obtains the first wavefront data of the cylindrical mirror to be tested measured by the interferometer in the complex cylindrical interference detection system when the interference fringe is zeroed. , which is expressed as:

[0038] Where, They represent the surface error distribution of the cylindrical mirror to be measured, the system error of the complex cylindrical interferometry detection system, the surface error distribution of the compensation mirror in the complex cylindrical interferometry detection system, and the return error introduced by non-zero position detection, respectively. Among them, x and y represent the coordinate axes of the complex cylindrical interferometry detection system, the x-axis is the curvature direction of the cylindrical mirror to be measured, and the y-axis is the non-curvature direction.

[0039] In this way, after obtaining the first wavefront data, the cylindrical mirror to be tested can be moved, that is, the cylindrical mirror to be tested in the complex cylindrical interference detection system is controlled to move once along the curvature direction (the moving distance is ), without making other posture adjustments, the detection result of the interferometer in the complex cylindrical interferometry detection system is:

[0040] Where, represents the second wave front data, It indicates the surface shape distribution error corresponding to the cylindrical mirror to be measured after it moves once along the curvature direction. It indicates the distance that the cylindrical mirror to be tested moves once along the curvature direction, and It indicates the misalignment aberration caused by the cylindrical lens to be tested moving once along the curvature direction.

[0041] Similarly, after moving once (i.e. moving After that, the cylindrical mirror to be tested is moved again, that is, it is moved again (i.e., it is moved again). ), at this time, the detection result of the interferometer in the complex cylindrical interference detection system is:

[0042] Where, represents the third wave front data, It indicates the surface shape distribution error of the cylindrical mirror to be tested after it moves once along the curvature direction and then moves once again, that is, it moves 2 The corresponding surface shape distribution error.

[0043] In this way, after the interferometer obtains the above three wavefront data, it can transmit them to the computer. Then, the computer can construct the second-order differential wavefront data of the cylindrical mirror to be tested to eliminate the misalignment aberration based on them. The construction process can be but is not limited to the following step S2.

[0044] S2. Based on the first wavefront data, the second wavefront data, and the third wavefront data, and using a pseudo-shearing method, construct second-order differential wavefront data to eliminate the misalignment aberration of the cylindrical lens under test. In a specific application, for example, but not limited to, the following steps S21 and S22 can be used to construct the aforementioned second-order differential wavefront data.

[0045] S21. Calculate the difference between the second wavefront data and the first wavefront data to obtain first differential wavefront data, and calculate the difference between the third wavefront data and the second wavefront data to obtain second differential wavefront data.

[0046] Specifically, the first differential wavefront data Expressed as:

[0047] Similarly, the second differential wavefront data Then:

[0048] At the same time, in this embodiment, when the shear When the moving distance is small enough, the differential wavefront can be approximately considered as the ideal differential wavefront of the cylindrical lens to be tested.

[0049] In this way, after obtaining the first-order differential wavefront data, the second-order differential wavefront data can be constructed based on it, and the process is shown in the following step S22.

[0050] S22. Subtracting the first differential wavefront data from the second differential wavefront data to obtain the second-order differential wavefront data; wherein the second-order differential wavefront data can be, but is not limited to, represented as:

[0051] It can be seen from the above second-order differential wavefront data that it does not contain misalignment aberration. Therefore, by subtracting the second differential wavefront data from the first differential wavefront data, the second-order differential wavefront data without misalignment aberration can be obtained.

[0052] After obtaining the second-order differential wavefront data without misalignment aberration through the aforementioned steps S21 and S22, the first-order differential wavefront data without misalignment aberration can be reconstructed based on the data, and the process is shown in the following step S3.

[0053] S3. Using a time-frequency domain conversion algorithm, a second-order differential frequency domain data conversion formula is established between the second-order differential wavefront data that eliminates misalignment aberrations and the first-order differential wavefront data of the cylindrical lens to be tested. This is then used to perform unidirectional reconstruction of the second-order differential frequency domain data conversion formula. A smoothing factor is added during the unidirectional reconstruction process to smooth the fringe noise generated by the unidirectional reconstruction, thereby obtaining the first-order differential wavefront data without misalignment aberrations corresponding to the cylindrical lens to be tested.

[0054] In specific applications, the idea of ​​unidirectional reconstruction is based on the time-frequency domain conversion method to reconstruct the first-order difference non-misalignment aberration wavefront data, that is: using the time-frequency domain conversion method, only one shearing direction is required to establish the mathematical relationship between the frequency domain and the differential operation through the Fourier transform; then, the corresponding first-order difference non-misalignment aberration feature is derived through the inverse Fourier transform; at the same time, since noise will propagate along the entire integration process during unidirectional reconstruction, resulting in stripes parallel to the integration direction, therefore, while integrating along the curvature direction, it is also necessary to perform smoothing along the non-curvature direction; among them, taking the above-mentioned specific process of generating the first-order difference non-misalignment aberration wavefront data using the time-frequency domain method as an example, it can be but not limited to the following steps S31 to S34.

[0055] S31. The second-order differential wavefront data is converted to use the first differential wavefront data to represent the second differential wavefront data in the second-order differential wavefront data, thereby obtaining the converted second-order differential wavefront data. In specific implementation, it can be seen from the formula of the second-order differential wavefront data that it contains the first differential wavefront data and the second differential wavefront data. In order to obtain the misalignment aberration, the second differential wavefront data in the second-order differential wavefront data needs to be represented by the first differential wavefront data. In this way, the entire second-order differential wavefront data only contains parameter.

[0056] Therefore, after using the first differential wavefront data to represent the second differential wavefront data, the converted second-order differential wavefront data can be expressed as: , where represents the number of second-order difference wavefronts after transformation, is the second differential wavefront data represented by the first differential wavefront data. Therefore, it can be seen from the formula that the entire second-order differential wavefront data only contains the first differential wavefront data. Based on this, by performing Fourier transform on it, suppressing noise, and then performing inverse transform, the first-order differential data without misalignment aberration can be obtained.

[0057] The Fourier transform process is shown in the following step S32.

[0058] S32. Performing Fourier transform processing on the converted second-order differential wavefront data to obtain the second-order differential frequency domain data conversion formula; in specific implementation, this is equivalent to performing Fourier transform on the second-order partial derivatives (i.e., the aforementioned converted second-order differential wavefront data) to convert the spatial domain information into the frequency domain for processing.

[0059] Among them, the Fourier transform can be expressed as: , Where, represents the Fourier transform, Represents the frequency domain representation corresponding to the transformed second-order difference wavefront data.

[0060] At the same time, according to the time-shift property of Fourier transform, the translation in real space is , which is equivalent to multiplying in Fourier space by , so the frequency domain representation corresponding to the second-order differential wavefront data after the above conversion can be converted to:

[0061] Where, Represents the aforementioned second-order differential frequency domain data conversion formula, express The corresponding frequency domain data, express The corresponding frequency domain data, represents the frequency coordinate in two-dimensional Fourier space, It represents the moving distance corresponding to one movement of the cylindrical mirror to be tested along the curvature direction. Represents an imaginary unit.

[0062] Therefore, after the Fourier transform of the converted second-order differential wavefront data is completed through the above formula, noise suppression can be performed, and the process is shown in the following step S33.

[0063] S33. Based on the smoothing factor, regularization is performed on the second-order difference frequency domain data transformation formula to obtain regularized difference frequency domain data. In this embodiment, regularization is performed by introducing a frequency-dependent regularization term into the second-order difference frequency domain data. This, combined with the smoothing factor, can suppress the amplification of streak noise. The regularization process is as follows:

[0064] In the above formula, represents the regularized difference frequency domain data, Represents the second-order differential frequency domain data conversion formula, represents the frequency coordinate in two-dimensional Fourier space, represents the smoothing factor, , represents the intermediate parameters, represents the complex conjugate symbol, where ,and Represents an imaginary unit.

[0065] Therefore, based on the above formula, after the regularized differential frequency domain data is obtained, it can be subjected to inverse Fourier transform processing to obtain first-order differential wavefront data without misalignment aberration, and the process is shown in the following step S34.

[0066] S34. Performing inverse Fourier transform processing on the regularized differential frequency domain data to reconstruct the first-order differential non-misaligned aberration wavefront data after the inverse Fourier transform processing.

[0067] In this embodiment, the first-order difference non-misaligned aberration wavefront data is expressed as:

[0068] Thus, it can be seen from the above formula that the first-order differential wavefront data obtained after the inverse Fourier transform does not contain misalignment aberration (i.e. ).

[0069] Thus, through the aforementioned steps S31 to S34, the first-order differential wavefront data without misalignment aberration can be obtained. Then, the misalignment aberration caused by the movement of the cylindrical lens to be tested along the curvature direction can be reconstructed in combination with the measured first-order differential wavefront data. The process is shown in the following step S4.

[0070] S4. Obtaining measured first-order difference data of the cylindrical mirror to be tested, and subtracting the measured first-order difference data from the first-order difference wavefront data without misalignment to reconstruct the misalignment aberration caused by the movement of the cylindrical mirror to be tested along the curvature direction, so as to determine the surface error of the cylindrical mirror to be tested based on the misalignment aberration.

[0071] In this embodiment, the first differential wavefront data obtained by subtracting the first wavefront data from the second wavefront data is used as the measured first-order differential data. Therefore, the reconstructed misalignment aberration caused by the movement of the cylindrical lens to be tested along the curvature direction is:

[0072] Where, represents the misalignment aberration, represents the first-order difference non-misaligned aberration wavefront data, represents the measured first-order difference data.

[0073] In this way, after obtaining the misalignment aberration caused by the movement of the cylindrical mirror to be tested along the curvature direction, the misalignment aberration can be subtracted from the differential wavefront obtained by subsequently moving the cylindrical mirror to be tested in the orthogonal direction, thereby obtaining the differential wavefront data in the orthogonal direction without misalignment aberration. Finally, based on this, the surface error of the cylindrical mirror to be tested can be accurately restored. The specific process is as follows: First, the measured differential wavefront data obtained by moving the cylindrical mirror to be tested along the orthogonal direction is obtained; then, the misalignment aberration is subtracted from the measured differential wavefront data to obtain the ideal differential wavefront data; finally, based on the ideal differential wavefront data, the surface error of the cylindrical mirror to be tested is obtained by using a wave surface integral restoration algorithm.

[0074] Specifically, the measured differential wavefront data obtained by moving the cylindrical mirror to be measured in the orthogonal direction refers to: Control the movement of the cylindrical mirror to be tested in the complex cylindrical interference detection system along the x-axis (i.e. curvature direction) , get a wavefront data (i.e. the second wavefront data mentioned above), move along the y-axis direction at the zero position , and the fourth wavefront data is obtained; therefore, the differential wavefront data corresponding to the orthogonal movement is: the second wavefront data minus the first wavefront data to obtain the first orthogonal differential wavefront data, and the fourth wavefront data minus the first wavefront data to obtain the second orthogonal differential wavefront data; in this way, the first orthogonal differential wavefront data is used to subtract the reconstructed misalignment aberration, and then combined with the second orthogonal differential wavefront data to form the ideal differential wavefront data; finally, based on the ideal differential wavefront data and using the wave surface integral restoration algorithm, the surface error of the cylindrical mirror to be measured can be obtained.

[0075] Therefore, through the misalignment aberration reconstruction method in complex cylindrical pseudo-shearing interference detection described in detail in the aforementioned steps S1 to S4, the present invention can ensure the accuracy of the orthogonal differential wavefront data used in reconstructing the cylindrical surface shape by reconstructing the misalignment aberration, thereby improving the reconstruction accuracy of the cylindrical mirror surface shape error.

[0076] See also Figure 3As shown, in a possible design, the second aspect of this embodiment provides an application example of the method described in the first aspect of the embodiment, that is, using the method provided by the first aspect of the embodiment to simulate and reconstruct the misalignment aberration generated when a complex cylindrical mirror moves along the curvature direction.

[0077] In this embodiment, the size of the cylindrical mirror is 157mm×100mm, the wavelength of the interferometer is 632.8nm, the imaging resolution is 392.5pixel×250pixel, and the differential step size is set to 1pixel, i.e. 0.4mm; wherein, the first measurement result like Figure 3 As shown in Figure (a); the misalignment aberration introduced by simulating movement along the curvature direction is as follows Figure 3 As shown in Figure (g); after the cylindrical mirror is moved 0.4mm along the curvature direction, the second measurement result like Figure 3 As shown in Figure (b); after moving the cylindrical mirror 0.4mm along the curvature direction, the third measurement result like Figure 3 As shown in Figure (c).

[0078] Then, the first-order difference data in the curvature direction obtained by the method described in the first aspect of the embodiment is and the second-order difference data in the curvature direction , respectively as Figure 3 As shown in Figures (d) and (e) in the figure; then, the reconstructed first-order difference data without misalignment aberration is obtained , such as Figure 3 As shown in Figure (f) in the figure; then, , thus obtaining the misalignment aberration, such as Figure 3 As shown in Figure (h); Finally, the reconstructed misalignment aberration is subtracted from the misalignment aberration introduced by the simulation to obtain the residual, as shown in Figure (h); Figure 3 As shown in Figure (i), it can be seen from the figure that the PV of the residual is only 0.34nm and the RMS is 0.25nm; this shows that this method can accurately reconstruct the misalignment aberration introduced by the movement of the complex cylindrical mirror along the curvature direction, thereby helping to accurately restore the wavefront information of the complex cylindrical surface.

[0079] like Figure 4 As shown, the third aspect of this embodiment provides a hardware device for implementing the misalignment aberration reconstruction method in complex cylindrical pseudo-shearing interferometry detection described in the first aspect of the embodiment, including: The detection unit is configured to acquire first wavefront data of the to-be-tested cylindrical mirror detected by the complex cylindrical interferometric detection system when the interference fringes are zeroed, and control the to-be-tested cylindrical mirror in the complex cylindrical interferometric detection system to move along the curvature direction, so as to acquire second wavefront data and third wavefront data detected by the complex cylindrical interferometric detection system after the to-be-tested cylindrical mirror moves along the curvature direction, wherein the second wavefront data is wavefront data detected by the complex cylindrical interferometric detection system after the to-be-tested cylindrical mirror moves along the curvature direction once, and the third wavefront data is wavefront data detected by the complex cylindrical interferometric detection system after the to-be-tested cylindrical mirror moves along the curvature direction twice. The second-order difference unit is configured to construct second-order difference wavefront data of the to-be-tested cylindrical mirror eliminating misalignment aberration based on the first wavefront data, the second wavefront data and the third wavefront data, and by using a pseudo-shearing method. The misalignment aberration reconstruction unit is configured to establish a second-order difference frequency domain data conversion formula between the second-order difference wavefront data eliminating misalignment aberration and first-order difference wavefront data of the to-be-tested cylindrical mirror by using a time-frequency domain conversion algorithm, reconstruct the second-order difference frequency domain data conversion formula in a single direction, and add a smoothing factor in the single direction reconstruction process to smooth the fringe noise generated in the single direction reconstruction, so as to obtain the first-order difference misalignment-free aberration wavefront data corresponding to the to-be-tested cylindrical mirror. The misalignment aberration reconstruction unit is further configured to acquire measured first-order difference data of the to-be-tested cylindrical mirror, and subtract the measured first-order difference data from the first-order difference misalignment-free aberration wavefront data, so as to reconstruct misalignment aberration generated by the to-be-tested cylindrical mirror moving along the curvature direction, so as to determine the surface shape error of the to-be-tested cylindrical mirror based on the misalignment aberration.

[0080] The working process, working details and technical effects of the device provided in this embodiment can be referred to the first aspect of the embodiment, which will not be repeated here.

[0081] As shown in Figure 5 The fourth aspect of the embodiment provides another misalignment aberration reconstruction device in complex cylindrical pseudo-shearing interferometric detection, taking an electronic device as an example, which comprises a memory, a processor and a transceiver connected in sequence, wherein the memory is configured to store a computer program, the transceiver is configured to receive and send messages, and the processor is configured to read the computer program and execute the misalignment aberration reconstruction method in complex cylindrical pseudo-shearing interferometric detection as described in the first aspect of the embodiment.

[0082] The working process, working details and technical effects of the electronic device provided in this embodiment can be referred to the first aspect of the embodiment, which will not be repeated here.

[0083] The fifth aspect of this embodiment provides a storage medium that stores instructions for the misalignment aberration reconstruction method in the complex cylindrical pseudo-shearing interference detection described in the first aspect of the embodiment, that is, the storage medium stores instructions, and when the instructions are run on a computer, the misalignment aberration reconstruction method in the complex cylindrical pseudo-shearing interference detection described in the first aspect of the embodiment is executed.

[0084] The working process, working details and technical effects of the storage medium provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0085] The sixth aspect of this embodiment provides a computer program product comprising instructions, which, when executed on a computer, causes the computer to execute the misalignment aberration reconstruction method in complex cylindrical pseudo-shearing interference detection as described in the first aspect of the embodiment, wherein the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device.

[0086] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for reconstructing misalignment aberration in complex cylindrical pseudo-shearing interferometry detection, characterized in that: include: Acquiring first wavefront data of the cylindrical mirror to be measured detected by the complex cylindrical interference detection system when the interference fringes are zeroed, and controlling the cylindrical mirror to be measured in the complex cylindrical interference detection system to move along the direction of curvature, so as to obtain second wavefront data and third wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves along the direction of curvature, wherein the second wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the direction of curvature, and the third wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the direction of curvature; Based on the first wavefront data, the second wavefront data and the third wavefront data, and using the pseudo shearing method, the second-order differential wavefront data of the cylindrical lens to be tested is constructed to eliminate the misalignment aberration; A time-frequency domain conversion algorithm is used to establish a second-order differential frequency domain data conversion formula between the second-order differential wavefront data that eliminates the misalignment aberration and the first-order differential wavefront data of the cylindrical lens to be tested, so as to perform unidirectional reconstruction on the second-order differential frequency domain data conversion formula. A smoothing factor is added during the unidirectional reconstruction process to smooth the fringe noise generated by the unidirectional reconstruction, thereby obtaining the first-order differential wavefront data without misalignment aberration corresponding to the cylindrical lens to be tested. The measured first-order difference data of the cylindrical mirror to be tested is obtained, and the measured first-order difference data is subtracted from the first-order difference non-misalignment aberration wavefront data to reconstruct the misalignment aberration caused by the movement of the cylindrical mirror to be tested along the curvature direction, so as to determine the surface error of the cylindrical mirror to be tested based on the misalignment aberration.

2. The method according to claim 1, characterized in that The cylindrical mirror to be tested generates the misalignment aberration only when it moves along the curvature direction, and the moving distance of the cylindrical mirror to be tested is the same each time it moves along the curvature direction; Among them, the first wavefront data of the cylindrical mirror to be tested detected by the complex cylindrical interferometry detection system is: Where, represents the first wavefront data, The following table represents the surface error distribution of the cylindrical mirror to be measured, the system error of the complex cylindrical interferometry detection system, the surface error distribution of the compensation mirror in the complex cylindrical interferometry detection system, and the return error introduced by the non-zero position detection, where x and y represent the coordinate axes of the complex cylindrical interferometry detection system, the x-axis is the curvature direction of the cylindrical mirror to be measured, and the y-axis is the non-curvature direction; After the cylindrical mirror to be tested moves once along the curvature direction, the second wavefront data detected by the complex cylindrical interferometry detection system is: Where, represents the second wave front data, It indicates the surface shape distribution error corresponding to the cylindrical mirror to be measured after it moves once along the curvature direction. Indicates the distance that the cylindrical mirror to be tested moves once along the curvature direction. It indicates the misalignment aberration caused by the cylindrical lens to be tested moving once along the curvature direction; Correspondingly, after the cylindrical mirror to be tested moves once along the curvature direction and then moves once again, the third wavefront data detected by the complex cylindrical interferometry detection system is: Where, represents the third wave front data, It indicates the surface shape distribution error of the cylindrical mirror to be measured after it moves once along the curvature direction and then moves again.

3. The method according to claim 2, characterized in that Based on the first wavefront data, the second wavefront data and the third wavefront data, and using the pseudo-shearing method, the second-order differential wavefront data of the cylindrical lens to be tested is constructed to eliminate the misalignment aberration, including: calculating a difference between the second wavefront data and the first wavefront data to obtain first differential wavefront data, and calculating a difference between the third wavefront data and the second wavefront data to obtain second differential wavefront data; The first differential wavefront data and the second differential wavefront data are respectively: Where, represents the first differential wavefront data, represents the second differential wavefront data; Subtracting the first differential wavefront data from the second differential wavefront data to obtain the second-order differential wavefront data; Wherein, the second-order differential wavefront data is: Where, represents the second-order difference wavefront data.

4. The method according to claim 1, wherein The second-order differential wavefront data is constructed based on the first-order differential wavefront data of the cylindrical lens to be tested, wherein the first-order differential wavefront data includes first differential wavefront data and second differential wavefront data, and the first differential wavefront data is the difference between the second wavefront data and the first wavefront data, and the second differential wavefront data is the difference between the third wavefront data and the second wavefront data; Among them, a time-frequency domain conversion algorithm is used to establish a second-order differential frequency domain data conversion formula between the second-order differential wavefront data that eliminates the misalignment aberration and the first-order differential wavefront data of the cylindrical lens to be tested, so as to perform unidirectional reconstruction on the second-order differential frequency domain data conversion formula. A smoothing factor is added in the unidirectional reconstruction process to smooth the fringe noise generated by the unidirectional reconstruction, and the first-order differential wavefront data without misalignment aberration corresponding to the cylindrical lens to be tested is obtained, including: performing conversion processing on the second-order differential wavefront data so as to use the first differential wavefront data to represent second differential wavefront data in the second-order differential wavefront data, thereby obtaining converted second-order differential wavefront data; Performing Fourier transform processing on the converted second-order differential wavefront data to obtain the second-order differential frequency domain data conversion formula; Based on the smoothing factor, the second-order differential frequency domain data conversion formula is regularized to obtain regularized differential frequency domain data; The regularized differential frequency domain data is subjected to inverse Fourier transform processing to reconstruct the first-order differential non-misaligned aberration wavefront data after the inverse Fourier transform processing.

5. The method according to claim 4, characterized in that The converted second-order differential wavefront data is: Where, represents the number of second-order difference wavefronts after transformation, represents the first differential wavefront data, represents the second differential wavefront data, representing second differential wavefront data represented using the first differential wavefront data; Correspondingly, the second-order differential frequency domain data conversion formula is: Where, Represents the second-order differential frequency domain data conversion formula, represents the Fourier transform, express The corresponding frequency domain data, express The corresponding frequency domain data, represents the frequency coordinate in two-dimensional Fourier space, It represents the moving distance corresponding to one movement of the cylindrical mirror to be tested along the curvature direction. Represents an imaginary unit.

6. The method according to claim 4, characterized in that Based on the smoothing factor, the second-order differential frequency domain data conversion formula is regularized to obtain regularized differential frequency domain data, including: Based on the smoothing factor and using the following formula, the second-order differential frequency domain data conversion formula is regularized to obtain the regularized differential frequency domain data; Where, represents the regularized difference frequency domain data, Represents the second-order differential frequency domain data conversion formula, represents the frequency coordinate in two-dimensional Fourier space, represents the smoothing factor, , represents the intermediate parameters, represents the complex conjugate symbol, where ,and It represents the moving distance corresponding to one movement of the cylindrical mirror to be tested along the curvature direction. Represents an imaginary unit.

7. The method according to claim 6, characterized in that The first-order difference non-misaligned aberration wavefront data is: In the above formula, represents the first-order difference non-misaligned aberration wavefront data, represents the inverse Fourier transform, It indicates the surface shape distribution error corresponding to the cylindrical mirror to be measured after it moves once along the curvature direction. Indicates the surface error distribution of the cylindrical mirror to be measured.

8. The method according to claim 1, characterized in that subtracting the first wavefront data from the second wavefront data to obtain first differential wavefront data as the measured first-order differential data; Among them, the misalignment aberration caused by the reconstructed movement of the cylindrical mirror to be tested along the curvature direction is: Where, represents the misalignment aberration, represents the first-order difference non-misaligned aberration wavefront data, represents the measured first-order difference data; Correspondingly, determining the surface error of the cylindrical mirror to be measured based on the misalignment aberration includes: Acquire measured differential wavefront data obtained by moving the cylindrical mirror to be measured along the orthogonal direction; subtracting the misalignment aberration from the measured differential wavefront data to obtain ideal differential wavefront data; Based on the ideal differential wavefront data and using a wave surface integral restoration algorithm, the surface shape error of the cylindrical mirror to be measured is obtained.

9. A device for reconstructing misalignment aberration in complex cylindrical pseudo-shearing interferometry detection, characterized in that: include: a detection unit, configured to obtain first wavefront data of the cylindrical mirror to be measured detected by the complex cylindrical interference detection system when the interference fringes are zeroed, and to control the cylindrical mirror to be measured in the complex cylindrical interference detection system to move along the direction of curvature, so as to obtain second and third wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves along the direction of curvature, wherein the second wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the direction of curvature, and the third wavefront data is the wavefront data detected by the complex cylindrical interference detection system after the cylindrical mirror to be measured moves once along the direction of curvature; A second-order difference unit is used to construct second-order difference wavefront data for eliminating misalignment aberration of the cylindrical lens to be tested based on the first wavefront data, the second wavefront data and the third wavefront data and using a pseudo-shearing method; a misalignment aberration reconstruction unit, configured to use a time-frequency domain conversion algorithm to establish a second-order differential frequency domain data conversion formula between the second-order differential wavefront data that eliminates misalignment aberrations and the first-order differential wavefront data of the cylindrical lens to be tested, so as to perform unidirectional reconstruction of the second-order differential frequency domain data conversion formula, and to add a smoothing factor during the unidirectional reconstruction process to smooth the fringe noise generated by the unidirectional reconstruction, thereby obtaining the first-order differential wavefront data without misalignment aberrations corresponding to the cylindrical lens to be tested; The misalignment aberration reconstruction unit is further used to obtain the measured first-order difference data of the cylindrical mirror to be tested, and subtract the measured first-order difference data from the first-order difference wavefront data without misalignment aberration to reconstruct the misalignment aberration caused by the movement of the cylindrical mirror to be tested along the curvature direction, so as to determine the surface error of the cylindrical mirror to be tested based on the misalignment aberration.

10. An electronic device, characterized in that: include: A memory, a processor, and a transceiver that are sequentially connected in communication, wherein the memory is used to store a computer program, the transceiver is used to send and receive messages, and the processor is used to read the computer program, and execute the misalignment aberration reconstruction method in complex cylindrical pseudo-shearing interferometry detection as described in any one of claims 1 to 8.

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