Rapid correction method for projection distortion of interferometric measurement of surface shape of off-axis parabolic mirror

Abstract

A rapid correction method for projection distortion of interferometric measurement of the surface shape of an off-axis parabolic mirror, comprising the steps: adjusting an auto-collimating interference detection light path: performing preliminary adjustment of the position of an off-axis parabolic mirror to be corrected, so that the optical axis of an interferometer preliminarily overlaps with central light of said off-axis parabolic mirror; translating the position of the off-axis parabolic mirror relative to the focal point thereof until the distance from the off-axis parabolic mirror to the focal point thereof is equal to a preset distance, and performing fine-tuning by means of a fringe pattern measured by the interferometer and Z3, Z4, and Z5 items corresponding to Zernike coefficients, until the error of the measurement is minimized; and, on the basis of adjusted auto-collimating interference detection light path, correcting projection distortion of interferometric measurement of the surface shape of the off-axis parabolic mirror to be corrected. By means of optimizing the adjustment mode of the auto-collimating interference detection light path and optimizing the correction method for the distortion, the entire distortion correction process is simple, the computational complexity thereof is low, and the correction efficiency and accuracy thereof are high.

Description

A fast correction method for surface projection distortion in off-axis parabolic reflector interferometry Technical Field

[0001] The present invention relates to the field of optical processing technology, and in particular to a method for quickly correcting surface projection distortion in off-axis parabolic reflector interference measurement. Background Art

[0002] Optical imaging applications are ubiquitous in our daily lives, but in reality, imaging systems rarely achieve perfect imaging. The difference between the ideal image and the actual image is called an aberration, and distortion is one of these aberrations in optical imaging systems. Unlike other aberrations (coma, astigmatism, field curvature, spherical aberration, etc.), when the imaging surface is flat, distortion only affects the geometric shape of the image and does not alter the image clarity. Therefore, optical systems generally allow for a certain amount of residual distortion. Because these systems are not used in certain scenarios with special requirements, such as precision measurement, a certain degree of geometric distortion is negligible to the user as long as the imaging resolution is not compromised. However, when the imaging resolution of the optical system is required to be higher, the field of view is larger, and sometimes certain restrictions are placed on the spatial structure of the entire optical system, relatively large residual distortion will appear, resulting in severe image distortion, which can affect the user's observation and cause misjudgment.

[0003] With the continuous advancement of optical processing and precision optical inspection technologies in recent years, secondary aspheric surfaces have attracted significant attention in the development of large-aperture optical systems due to their aberration-free nature at their geometric focus. Off-axis secondary aspheric surfaces have gained widespread application due to their advantages in simplifying optical system structure, improving imaging quality, and avoiding obstructions. Off-axis parabolic reflectors offer advantages over conventional collimators due to their ability to produce a unique, high-quality, and centrally obstructed parallel beam with a simple surface shape. When using an interferometer to inspect an off-axis parabolic reflector, the interferometer generates a standard spherical wave, which is reflected by the off-axis parabolic reflector. The resulting parallel light then returns via a flat mirror, where it interferes with the spherical standard mirror. However, the curvature of the off-axis parabolic reflector's surface along the optical axis varies widely, resulting in a non-linear relationship between the coordinate system of the mirror under test and the interferometer's measurement coordinate system. This can lead to distortion between the measured and actual data, and the feedback of such erroneous data can affect the accuracy of subsequent processing.

[0004] Currently, there are two main methods for distortion correction: one is theoretical correction, which uses professional optical design software to optimize the design and correct distortion; the other is image correction, which usually requires placing a reference mask in front of the mirror, establishing the relationship between the ideal image and the actual image through some calculation models, and using least squares fitting to determine the object-image distribution function to correct the distortion. Generally speaking, theoretical correction should be used as much as possible. If the requirements can be met, subsequent image correction can be omitted. However, theoretical correction requires strong optical design capabilities and the algorithm is complex to implement. In addition, when the optical system requires a larger field of view and higher imaging resolution, theoretical correction cannot fully meet the requirements. In image correction, the fitting polynomial must be reasonably selected according to the measurement object. When detecting large-aperture aspheric surfaces, the preparation of the reference mask and its position calibration process are relatively cumbersome, and the installation process also has certain risks.

[0005] Summary of the Invention

[0006] In order to solve the problem of projection distortion when interferometrically measuring the surface shape of an off-axis parabolic reflector, the present application provides a method for quickly correcting the projection distortion of the surface shape of an off-axis parabolic reflector by interferometric measurement. By optimizing the adjustment method of the self-collimating interferometric detection optical path and optimizing the distortion correction method, the entire distortion correction process is simplified, the computational complexity is low, the correction efficiency is high, and the accuracy is high.

[0007] The technical solutions provided by the present invention are as follows:

[0008] The present invention provides a method for quickly correcting surface projection distortion by interferometric measurement of an off-axis parabolic reflector, comprising the steps of:

[0009] Build and adjust a self-collimating interferometer detection optical path, which includes an interferometer, an off-axis parabolic reflector to be corrected, and a plane reflector; specifically, the steps include:

[0010] Preliminarily adjusting the position of the off-axis parabolic reflector to be corrected so that the optical axis of the interferometer and the central light of the off-axis parabolic reflector to be corrected are preliminarily coincident;

[0011] The position of the off-axis parabolic reflector to be corrected is translated relative to its focus until the distance from the off-axis parabolic reflector to its focus is equal to the preset distance, and the fringe pattern and the corresponding Zernike coefficients Z3, Z4, and Z5 measured by the interferometer are fine-tuned to the point where the measured error is minimum;

[0012] Correcting the projection distortion of the interferometric measurement surface of the off-axis parabolic reflector to be corrected based on the adjusted self-collimation interferometric detection optical path specifically includes the following steps:

[0013] Establishing a coordinate system: establishing a first coordinate system for the mother mirror of the off-axis parabolic reflector to be corrected, wherein the mother mirror is the entire parabolic reflector where the off-axis parabolic reflector to be corrected is located, and the off-axis parabolic reflector to be corrected is a part of the mother mirror, establishing a second coordinate system for the interferometer, and establishing a third coordinate system for the off-axis parabolic reflector to be corrected;

[0014] Converting the surface shape data in the second coordinate system measured by the interferometer into surface shape data in the first coordinate system through the coordinate transformation relationship between the second coordinate system and the first coordinate system;

[0015] According to the equation of the off-axis parabolic reflector to be corrected and the equation of the reflected light of the focus of the off-axis parabolic reflector to be corrected, the surface shape data in the first coordinate system is projected onto the off-axis parabolic reflector to be corrected, so as to obtain the projection data of the off-axis parabolic reflector to be corrected in the first coordinate system;

[0016] The projection data is converted into surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system through the coordinate transformation relationship between the first coordinate system and the third coordinate system.

[0017] Further preferably, the preset distance is the distance from the reflection boundary point of the off-axis parabolic reflector to be corrected at the boundary of its reflection range to the focus of the off-axis parabolic reflector to be corrected.

[0018] Further preferably, the distance from the reflection boundary point to the focus is calculated based on the processing parameters of the off-axis parabolic reflector to be corrected and the parabola equation of the off-axis parabolic reflector to be corrected.

[0019] Further preferably, the surface shape data in the second coordinate system measured by the interferometer is converted into surface shape data in the first coordinate system through the coordinate transformation relationship between the second coordinate system and the first coordinate system, specifically:

[0020] Among them, (X i , Y i , Z i ) is the surface shape data measured by the interferometer in the second coordinate system, f is the focal length of the off-axis parabolic reflector, and f i is the focal length of the interferometer after adding the standard mirror, α is the off-axis angle, and (X, Y, Z) is the surface data in the first coordinate system.

[0021] Further preferably, the projection data is converted into the surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system through the coordinate transformation relationship between the first coordinate system and the third coordinate system, specifically:

[0022] Among them, X0 is the off-axis amount, β is the equal thickness angle, X l and Y lThey are the X-axis projection data and Y-axis projection data of the off-axis parabolic reflector to be corrected in the first coordinate system, Z0 is the distance from the center of the off-axis parabolic reflector to be corrected to the vertex of the mother mirror in the Z-axis direction, (X L , Y L , Z L ) is the surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system.

[0023] Further preferably, the reflected light equation of the focus of the off-axis parabolic reflector to be corrected is:

[0024] Among them, (X, Y, Z) is the surface data in the first coordinate system, f is the focal length of the off-axis parabolic reflector, (X l , Y l , Z l ) is the projection data of the off-axis parabolic reflector to be corrected in the first coordinate system.

[0025] Further preferably, the position of the off-axis parabolic reflector to be corrected is preliminarily adjusted so that the optical axis of the interferometer and the central light of the off-axis parabolic reflector to be corrected preliminarily coincide with each other; specifically, an aperture is installed at the light exit position of the interferometer, and the positions of the off-axis parabolic reflector to be corrected and the plane reflector are adjusted so that the outgoing light beam returns through the plane reflector and passes through the center of the aperture after being reflected by the off-axis parabolic reflector to be corrected.

[0026] Further preferably, the establishing of the second coordinate system for the interferometer is specifically establishing the second coordinate system based on the center of the standard lens reference surface.

[0027] The method for correcting projection distortion of surface shape measured by interferometric measurement of an off-axis parabolic reflector provided by the present invention, in the process of adjusting the self-collimating interferometric detection optical path, based on the preliminary adjustment, the position of the off-axis parabolic reflector to be corrected relative to its focus is translated until the distance from the off-axis parabolic reflector to be corrected to its focus is equal to a preset distance, so as to minimize the surface shape error measured by the interferometer. That is, when adjusting the off-axis parabolic reflector to be corrected, it is not necessary to repeatedly calibrate and align the off-axis parabolic reflector to be corrected, thereby improving the efficiency of adjusting the off-axis parabolic reflector to be corrected in the self-collimating interferometric detection optical path; and when converting the projection data into the surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system, the surface shape data in the Z direction directly uses the original data measured by the interferometer, thereby simplifying the calculation process of distortion correction. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a diagram of the optical path of self-collimation interferometry detection;

[0029] Figure 2 is a schematic diagram of interferometer coordinate transformation;

[0030] Figure 3 is a schematic diagram of data projection;

[0031] FIG4 is a schematic diagram of coordinate transformation of a parabolic reflector;

[0032] FIG5 is a surface texture diagram of the off-axis parabolic reflector before correction;

[0033] Figure 6 is a surface texture diagram of the off-axis parabolic reflector after correction. DETAILED DESCRIPTION

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific embodiments of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings and other embodiments can be obtained based on these drawings without inventive work.

[0035] For the correction of projection distortion of off-axis parabolic reflector interferometry measurement surface shape, application number 2020100318819 discloses a technical solution, which includes calibration, construction of a self-collimating interferometry detection optical path, and projection distortion correction. Among them, the self-collimating interferometry detection optical path requires repeated adjustments, and the projection distortion modification solution requires calibration. The calibration process is very cumbersome. In short, the overall technical solution for distortion correction disclosed in the patent with application number 2020100318819 is too complicated and cumbersome.

[0036] The present application also requests protection for a method for quickly correcting projection distortion of an off-axis parabolic reflector interferometrically measured surface shape. The key technical points of the technical solution requested for protection in the present application are: based on the preliminary adjustment, the position of the off-axis parabolic reflector to be corrected relative to its focus is adjusted until the distance from the off-axis parabolic reflector to be corrected to its focus is equal to a preset distance, so that the surface shape error measured by the interferometer is minimized. That is, when adjusting the off-axis parabolic reflector to be corrected, there is no need to repeatedly calibrate and align the off-axis parabolic reflector to be corrected, thereby improving the efficiency of adjusting the off-axis parabolic reflector to be corrected in the self-collimation interference detection optical path; and when converting the projection data into the surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system, the surface shape data in the Z direction directly uses the original data measured by the interferometer, thereby simplifying the calculation process of distortion correction.

[0037] The projection distortion correction method provided in this application specifically includes the following steps.

[0038] S100: Build and adjust the autocollimation interferometry detection optical path.

[0039] The self-collimation interferometer detection optical path is shown in FIG1 , and the self-collimation interferometer detection optical path includes an interferometer, an off-axis parabolic reflector to be corrected, and a plane reflector; step S100 specifically includes the following steps:

[0040] S110: Preliminary adjustment is performed on the position of the off-axis parabolic reflector to be corrected, so that the optical axis of the interferometer and the central light of the off-axis parabolic reflector to be corrected are initially coincident.

[0041] Specifically, an aperture is installed at the light output position of the interferometer, and by adjusting the positions of the off-axis parabolic reflector to be corrected and the plane reflector, the outgoing light beam returns through the plane reflector, is reflected by the off-axis parabolic reflector to be corrected, and then passes through the center of the aperture.

[0042] S120: The position of the off-axis parabolic reflector to be corrected is translated relative to its focus until the distance from the off-axis parabolic reflector to be corrected to the focus is equal to the preset distance, and the fringe pattern measured by the interferometer and the Z3, Z4, and Z5 items of the corresponding Zernike coefficients are fine-tuned to the point where the measured error is minimum.

[0043] Before translating the off-axis parabolic reflector to be corrected relative to its focal position, it also involves exchanging the aperture for a standard lens.

[0044] Among them, the preset distance is the distance from the reflection boundary point of the off-axis parabolic reflector to be corrected at the boundary of its reflection range to the focus of the off-axis parabolic reflector to be corrected; the distance from the reflection boundary point to the focus is calculated based on the processing parameters of the off-axis parabolic reflector to be corrected and the parabola equation of the off-axis parabolic reflector to be corrected; as shown in Figure 1, the off-axis parabolic reflector to be corrected has two reflection boundary points at the boundary of its reflection range, and two preset distances, namely L1 and L2, can be obtained by calculation.

[0045] Since L1 and L2 are obtained, based on the preliminary adjustment in step S110, the position of the off-axis parabolic reflector to be corrected relative to its focus is directly adjusted until the distance from one reflection boundary point of the off-axis parabolic reflector to be corrected to the focus is equal to L1, and the distance from the other reflection boundary point to the focus is equal to L2, and the fringe pattern measured by the interferometer and the Z3, Z4, and Z5 items corresponding to the Zernike coefficients are fine-tuned to the point where the measured errors are minimum, wherein the interferometer can measure the corresponding fringe pattern through its own CCD image sensor, and the Z3, Z4, and Z5 items corresponding to the Zernike coefficients refer to the coefficients of the 3rd, 4th, and 5th items in the Zernike polynomial. For example, the Zernike polynomial can be a 36-term polynomial, and the interferometer can measure the corresponding fringe pattern through its own CCD image sensor. The Z3, Z4, and Z5 items corresponding to the Zernike coefficients refer to the coefficients of the 3rd, 4th, and 5th items in the Zernike polynomial. For example, the Zernike polynomial can be a 36-term polynomial. The measured fringe pattern and the corresponding Zernike coefficients Z3, Z4, and Z5 items are used to make final fine adjustments to the off-axis parabolic reflector to be corrected, so that the off-axis parabolic reflector to be corrected is adjusted to the point where the error measured by the interferometer is minimum, so that the off-axis parabolic reflector to be corrected is accurately positioned at a preset position; this adjustment scheme can enable the off-axis parabolic reflector to be corrected to be quickly and accurately positioned in the self-collimation interferometer detection optical path; while the existing scheme is to repeatedly adjust the off-axis parabolic reflector to be corrected based on the operator's operating experience when L1 and L2 are unknown; therefore, in the self-collimation interferometer detection optical path, the technical scheme of the present application is compared with the existing technical scheme. While ensuring the accuracy of distortion correction, it can also improve the efficiency of the installation and adjustment of the off-axis parabolic reflector to be corrected in the self-collimation interferometer detection optical path.

[0046] S200: Correcting the projection distortion of the interferometric measurement surface of the off-axis parabolic reflector to be corrected based on the adjusted self-collimation interferometric detection optical path.

[0047] The specific steps include:

[0048] S210: Establish a coordinate system.

[0049] A first coordinate system is established for the mother mirror of the off-axis parabolic reflector to be corrected, the mother mirror is the entire parabolic reflector where the off-axis parabolic reflector to be corrected is located, and the off-axis parabolic reflector to be corrected is a part of the mother mirror. A second coordinate system is established for the interferometer, and a third coordinate system is established for the off-axis parabolic reflector to be corrected.

[0050] Specifically, a first coordinate system is established with the vertex of the mother mirror of the off-axis parabolic reflector to be calibrated in the self-collimation interferometer detection optical path, a second coordinate system is established with the center point of the interferometer standard lens reference surface in the self-collimation interferometer detection optical path, and a third coordinate system is established with the center point of the off-axis parabolic reflector to be calibrated. For example, as shown in Figure 1, Oxyz is the first coordinate system established with the vertex point O of the mother mirror of the off-axis parabolic reflector; O i x i y i zi The center point O of the interferometer standard lens reference surface is i The second coordinate system established; L x L y L z L The center point O of the off-axis parabolic reflector is L The third coordinate system is established.

[0051] S220: Converting the surface shape data in the second coordinate system measured by the interferometer into surface shape data in the first coordinate system through a coordinate transformation relationship between the second coordinate system and the first coordinate system.

[0052] The surface data in the second coordinate system measured by the interferometer is converted into the surface data in the first coordinate system as shown in Figure 2. The specific transformation relationship is as follows:

[0053] Among them, (X i , Y i , Z i ) is the surface shape data measured by the interferometer in the second coordinate system, f is the focal length of the off-axis parabolic reflector, and f i is the focal length of the interferometer after adding the standard mirror, α is the off-axis angle, and (X, Y, Z) is the surface data in the first coordinate system.

[0054] S230: According to the equation of the off-axis parabolic reflector to be corrected and the equation of the reflected light of the focus of the off-axis parabolic reflector to be corrected, the surface shape data in the first coordinate system is projected onto the off-axis parabolic reflector to be corrected, and the projection data of the off-axis parabolic reflector to be corrected in the first coordinate system is obtained.

[0055] The data projection diagram is shown in Figure 3, where the light equation passing through the focus of the off-axis parabolic reflector to be corrected is:

[0056] Among them, (X, Y, Z) is the surface data in the first coordinate system, f is the focal length of the off-axis parabolic reflector, (X l , Y l , Z l ) is the projection data of the off-axis parabolic reflector to be corrected in the first coordinate system.

[0057] S240: Converting the projection data into surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system through a coordinate transformation relationship between the first coordinate system and the third coordinate system.

[0058] A schematic diagram of converting the projection data into the surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system is shown in FIG4 . The specific transformation relationship is as follows:

[0059] Among them, X0 is the off-axis amount, β is the equal thickness angle, X l and Y l They are the X-axis projection data and Y-axis projection data of the off-axis parabolic reflector to be corrected in the first coordinate system, Z0 is the distance from the center of the off-axis parabolic reflector to be corrected to the vertex of the mother mirror in the Z-axis direction, (X L , Y L , Z L ) is the surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system.

[0060] Since the distortion hardly occurs in the Z direction in the coordinate system constructed in this application, it can also be directly output (X L , Y L , Z i ) as the final data, so in this step, the surface data in the Z direction directly uses the original data measured by the interferometer, which simplifies the calculation process of distortion correction while ensuring the accuracy of correction.

[0061] Taking a Φ94 off-axis parabolic reflector as an example, when using a 4D interferometer to detect its texture, the measured data is shown in Figure 5. It can be seen intuitively that the lengths in the X and Y directions are inconsistent, indicating that projection distortion occurred during the measurement.

[0062] The correction method provided in this application was used to correct the distortion of a Φ94 off-axis parabolic reflector. The correction results are shown in Figure 6. In comparison, while PV, RMS, and Power remain virtually unchanged, the X-axis size after correction is adjusted to the same as the Y-axis size before correction, and the Y-axis size after correction is adjusted to within 0.3 mm of the pre-correction Y-axis size, which barely affects subsequent processing.

[0063] Since distortion in the coordinate system constructed in this application occurs almost entirely in the X-direction, the distortion ratio is defined as: |X-axis length - Y-axis length| / Y-axis length. From Figures 5 and 6, we can calculate that the distortion ratio was 2.07% before correction, and reduced to 0.37% after correction. In comparison, the technical solution provided by this application significantly improves projection distortion.

[0064] The above examples are used to illustrate the present invention, which are only used to help understand the present invention and are not intended to limit the present invention. Those skilled in the art can make several simple deductions, modifications or substitutions based on the concept of the present invention.

Claims

1. A method for quickly correcting surface projection distortion using off-axis parabolic reflector interferometry, characterized in that: Including steps: Build and adjust a self-collimating interferometer detection optical path, which includes an interferometer, an off-axis parabolic reflector to be corrected, and a plane reflector; specifically, the steps include: Preliminarily adjusting the position of the off-axis parabolic reflector to be corrected so that the optical axis of the interferometer and the central light of the off-axis parabolic reflector to be corrected are preliminarily coincident; The position of the off-axis parabolic reflector to be corrected is translated relative to its focus until the distance from the off-axis parabolic reflector to its focus is equal to the preset distance, and the fringe pattern and the corresponding Zernike coefficients Z3, Z4, and Z5 measured by the interferometer are fine-tuned to the point where the measured error is minimum; Correcting the projection distortion of the interferometric measurement surface of the off-axis parabolic reflector to be corrected based on the adjusted self-collimation interferometric detection optical path specifically includes the following steps: Establishing a coordinate system: establishing a first coordinate system for the mother mirror of the off-axis parabolic reflector to be corrected, wherein the mother mirror is the entire parabolic reflector where the off-axis parabolic reflector to be corrected is located, and the off-axis parabolic reflector to be corrected is a part of the mother mirror, establishing a second coordinate system for the interferometer, and establishing a third coordinate system for the off-axis parabolic reflector to be corrected; Converting the surface shape data in the second coordinate system measured by the interferometer into surface shape data in the first coordinate system through the coordinate transformation relationship between the second coordinate system and the first coordinate system; According to the equation of the off-axis parabolic reflector to be corrected and the equation of the reflected light of the focus of the off-axis parabolic reflector to be corrected, the surface shape data in the first coordinate system is projected onto the off-axis parabolic reflector to be corrected, so as to obtain the projection data of the off-axis parabolic reflector to be corrected in the first coordinate system; The projection data is converted into surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system through the coordinate transformation relationship between the first coordinate system and the third coordinate system.

2. The rapid correction method according to claim 1, wherein: The preset distance is the distance from the reflection boundary point of the off-axis parabolic reflector to be corrected at the boundary of its reflection range to the focus of the off-axis parabolic reflector to be corrected.

3. The rapid correction method according to claim 2, wherein: The distance from the reflection boundary point to the focus is calculated based on the processing parameters of the off-axis parabolic reflector to be corrected and the parabola equation of the off-axis parabolic reflector to be corrected.

4. The rapid correction method according to claim 1, wherein: The surface shape data in the second coordinate system measured by the interferometer is converted into surface shape data in the first coordinate system through the coordinate transformation relationship between the second coordinate system and the first coordinate system, specifically: Among them, (X i , Y i , Z i ) is the surface shape data measured by the interferometer in the second coordinate system, f is the focal length of the off-axis parabolic reflector, and f i is the focal length of the interferometer after adding the standard mirror, α is the off-axis angle, and (X, Y, Z) is the surface data in the first coordinate system.

5. The rapid correction method according to claim 1, wherein: The projection data is converted into the surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system through the coordinate transformation relationship between the first coordinate system and the third coordinate system, specifically: Among them, X0 is the off-axis amount, β is the equal thickness angle, X l and Y l They are the X-axis projection data and Y-axis projection data of the off-axis parabolic reflector to be corrected in the first coordinate system, Z0 is the distance from the center of the off-axis parabolic reflector to be corrected to the vertex of the mother mirror in the Z-axis direction, (X L , Y L , Z L ) is the surface shape data corresponding to the off-axis parabolic reflector to be corrected in the third coordinate system.

6. The rapid correction method according to claim 1, wherein: The light equation passing through the focus of the off-axis parabolic reflector to be corrected is: Among them, (X, Y, Z) is the surface data in the first coordinate system, f is the focal length of the off-axis parabolic reflector, (X l , Y l , Z l ) is the projection data of the off-axis parabolic reflector to be corrected in the first coordinate system.

7. The rapid correction method according to claim 1, wherein: The position of the off-axis parabolic reflector to be corrected is preliminarily adjusted so that the optical axis of the interferometer and the central light of the off-axis parabolic reflector to be corrected are preliminarily coincident. Specifically, an aperture is installed at the light output position of the interferometer, and the positions of the off-axis parabolic reflector to be corrected and the plane reflector are adjusted so that the outgoing light beam returns through the off-axis parabolic reflector to be corrected and the plane reflector in sequence, and passes through the center of the aperture after being reflected by the off-axis parabolic reflector to be corrected.

8. The rapid correction method according to claim 7, wherein: Before translating the off-axis parabolic reflector to be corrected relative to its focal position, it also involves exchanging the aperture for a standard lens.

9. The rapid correction method according to claim 8, wherein: The second coordinate system is established for the interferometer specifically by using the center of the standard lens reference surface to establish the second coordinate system.

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