Aspheric surface shape and parameter error transient measurement device and method

Abstract

The invention discloses an aspheric surface shape and parameter error transient measurement device and method, and the device comprises a polarization multiplexing interferometer host module which emits collimated or converged measurement light, receives the measurement light reflected from a measured surface, separates orthogonal polarized light, and detects first and second interference fringes; the first orthogonal polarization state correspondingly compensates the phase modulation of the surface shape of the measured surface, and the second orthogonal polarization state correspondingly measures the phase modulation of the axial distance from the measured surface to the polarization multiplexing phase modulation module; the interference diagram resolving module is used for resolving the first interference fringes to obtain first phase distribution, resolving the second interference fringes to obtain second phase distribution, and obtaining the axial distance from the actual measured surface to the polarization multiplexing phase modulation module according to the second phase distribution; the virtual interferometer module is used for simulating to obtain phase distribution corresponding to the ideal measured surface and the axial distance from the ideal measured surface to the polarization multiplexing phase modulation module; and the measured surface parameter resolving module is used for resolving to obtain the surface shape and the parameter error of the measured surface.

Description

Technical Field

[0001] This invention relates to the field of photoelectric detection technology, and more particularly to an apparatus for transient measurement of aspherical surface shape and parameter error, as well as the method used in this apparatus for transient measurement of aspherical surface shape and parameter error, which aims to achieve simultaneous high-precision transient measurement of aspherical surface shape and parameter error using a polarization multiplexing interference optical path. Background Technology

[0002] Space observation cameras are the "eyes in space" for humankind's understanding of the universe and the cornerstone of development in fields such as space astronomy. High-resolution space observation cameras are crucial for achieving fine-grained space observations. The aperture and precision of the core components of a space observation camera affect the imaging resolution, contrast, and the ability to finely observe faint celestial objects under ideal conditions. To improve resolution, the aperture requirements for core camera components such as aspherical and off-axis aspherical mirrors are constantly increasing. However, due to limitations in materials, measurement, processing, cost, transportation, and launch vehicles, the largest aperture single-mirror primary mirror launched internationally is currently 3.5 meters. Larger aperture primary mirrors typically employ synthetic aperture lens technology, and considering manufacturing costs and the complexity of splicing, the aperture of sub-mirrors is currently generally in the meter range (1.0–2.0 meters). Optical synthetic aperture technology "disassembles" large-aperture optical elements into multiple sub-aperture elements, using multi-aperture interferometry to achieve "reconstruction," resulting in wavefront quality equivalence with the overall large-aperture imaging system.

[0003] Optical synthetic aperture (OSA) technology has become an essential path to overcome the diffraction limit of single-aperture systems and achieve high-resolution imaging with large or even ultra-large apertures. The key to the success of OSA technology lies in achieving phase synchronization to reduce system wavefront aberrations. System wavefront aberrations mainly originate from: optical system design aberrations, errors in core optical components (surface shape errors, parameter errors, curvature radius consistency errors, etc.), assembly and adjustment errors, and environmental errors (gravity, temperature). The high precision and consistency of surface shape parameters in the core components of large-aperture space cameras present multi-dimensional difficulties and challenges to optical measurement and fabrication technologies.

[0004] Currently, interferometry is a commonly used high-precision measurement method, but it has the following limitations:

[0005] (1) It is difficult to integrate processing and measurement. Due to the sharp drop in measurement accuracy of interferometers under vibration, the surface shape measurement accuracy drops from the nanometer level to the hundred nanometer level, making it difficult to integrate with processing equipment. In addition, the large-aperture optical element fixtures used in processing and measurement equipment are not standardized, the stress state is inconsistent, and the surface shape changes reach the micrometer level.

[0006] (2) Surface shape and parameters cannot be measured simultaneously. Surface shape and parameter errors need to be measured using different equipment. Surface shape is mainly measured by an interferometer. Due to the relative measurement principle of interference, commercial interferometers do not have parameter measurement functions. Parameters are mainly obtained by measuring the surface shape with a profilometer and performing fitting analysis. Changing the measuring equipment will also lead to a decrease in measurement accuracy due to changes in clamping stress.

[0007] (3) Insufficient accuracy of parameter measurement. All types of contour measurement methods require scanning. The measurement error of mechanical motion and spatial displacement is on the order of tens of micrometers. The parameter fitting process is easily affected by random data fluctuations and non-orthogonality of the fitting function. Summary of the Invention

[0008] To overcome the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a device for transient measurement of aspherical surface shape and parameter error, which can achieve simultaneous and high-precision transient measurement of surface shape and parameter error.

[0009] The technical solution of this invention is: a device for transient measurement of aspherical surface shape and parameter error, comprising:

[0010] The polarization multiplexing interferometer main module includes a laser, a collimating lens, a beam splitter, a plane standard mirror or a spherical standard mirror, a quarter-wave plate, a polarization beam splitter, a first imaging lens, a first array detector, a second imaging lens, and a second array detector. This module emits collimated or converged measurement light and receives measurement light reflected back to the interferometer main module from the measured surface, separates orthogonally polarized light, and detects the first interference fringes generated by the first orthogonal polarization state and the second interference fringes generated by the second orthogonal polarization state.

[0011] The polarization multiplexing phase modulation module modulates the measurement light emitted from the polarization multiplexing interferometer main module. It performs phase modulation according to the two orthogonal polarization states of the measurement light. The first orthogonal polarization state corresponds to the phase modulation for compensating the surface shape of the measured surface, and the second orthogonal polarization state corresponds to the phase modulation for measuring the axial distance from the measured surface to the polarization multiplexing phase modulation module.

[0012] The interferogram solving module solves the first interference fringe to obtain the first phase distribution, solves the second interference fringe to obtain the second phase distribution, and further obtains the axial distance from the actual measured surface to the polarization multiplexing phase modulation module based on the second phase distribution.

[0013] The virtual interferometer module simulates the phase distribution corresponding to the ideal measured surface, as well as the axial distance from the ideal measured surface to the polarization multiplexing phase modulation module.

[0014] The measured surface parameter calculation module calculates the surface shape and parameter error of the measured surface based on the ideal and actual phase distribution and the axial distance from the measured surface to the polarization multiplexing phase modulation module.

[0015] This invention utilizes polarization multiplexing to simultaneously and transiently acquire two sets of interferograms. The first interference fringe is used to obtain the phase distribution of the actual measured surface after compensation, and the second interference fringe is used to obtain the axial distance from the actual measured surface to the polarization multiplexing phase modulation module. By combining the virtual interferometer module and the measured surface parameter calculation module, the surface shape and parameter errors of the measured aspheric surface can be obtained. This device contains no moving parts and can achieve transient measurement, thus solving the problem of integration with machine tools. By simultaneously solving for surface shape and parameter errors using the virtual interferometer and the measured surface parameter calculation module, it solves the problem of the inability to measure surface shape and parameters simultaneously. Axial distance measurement using interferometry achieves micrometer-level accuracy, effectively improving parameter measurement accuracy. In summary, this invention achieves simultaneous high-precision transient measurement of surface shape and parameter errors through polarization multiplexing phase modulation, which is beneficial for rapid, high-precision, and highly consistent production testing of large batches of aspheric surfaces.

[0016] A method for operating the apparatus for transient measurement of aspherical surface shape and parameter error is also provided, comprising the following steps:

[0017] (1) Constructing a virtual interferometer: Modeling a virtual interferometer using the nominal parameters of the measured surface, the polarization multiplexing interferometer host module, and the polarization multiplexing phase modulation module;

[0018] (2) Simulate the ideal phase distribution: Use a virtual interferometer to simulate the phase distribution corresponding to the ideal measured surface;

[0019] (3) Simulate the ideal axial distance: The axial distance from the ideal measured surface to the polarization multiplexing phase modulation module is obtained by simulating using a virtual interferometer;

[0020] (4) Constructing the actual interferometer: Using the actual surface under test, the polarization multiplexing interferometer main module, and the polarization multiplexing phase modulation module, construct the actual interferometer and record the first and second interference fringes;

[0021] (5) Measure the actual phase distribution: use the first interference fringe to calculate the first phase distribution, that is, the phase distribution corresponding to the actual measured surface;

[0022] (6) Measure the actual axial distance: use the second interference fringes to solve the second phase distribution, and further calculate the actual axial distance from the measured surface to the polarization multiplexing phase modulation module;

[0023] (7) Calculate the surface shape and parameter errors: Based on the ideal and actual phase distributions and the axial distance from the measured surface to the polarization multiplexing phase modulation module, the surface shape and parameters of the measured surface are calculated.

[0024] error. Attached Figure Description

[0025] Figure 1This is a schematic diagram of the device for transient measurement of aspherical surface shape and parameter error according to the present invention.

[0026] Figure 2 This is a flowchart of the method of using the apparatus for transient measurement of aspherical surface shape and parameter error according to the present invention.

[0027] Wherein: 1-Laser, 2-Collimating lens, 3-Beam splitter, 4-Planar standard mirror, 5-Spherical lens, 6-Polarization multiplexing phase modulator, 7-Measured surface, 8-Polarization multiplexing phase modulation module, 9-Polarization beam splitter, 10-Second imaging lens, 11-Second array detector, 12-Polarization multiplexing interferometer main module, 13-First imaging lens, 14-First array detector, 15-Quarter-wave plate. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0029] It should be noted that the term "comprising" and any variations thereof in the specification, claims and accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products or devices.

[0030] like Figure 1 As shown, this device for transient measurement of aspherical surface shape and parameter error includes:

[0031] The polarization multiplexing interferometer main module 12 includes a laser 1, a collimating mirror 2, a beam splitter 3, a plane standard mirror 4 or a spherical standard mirror, a quarter-wave plate 15, a polarization beam splitter 9, a first imaging lens 13, a first array detector 14, a second imaging lens 10, and a second array detector 11. This module emits collimated or converged measurement light and receives measurement light reflected back to the interferometer main module from the measured surface, separates orthogonally polarized light, and detects the first interference fringes generated by the first orthogonal polarization state and the second interference fringes generated by the second orthogonal polarization state.

[0032] The polarization multiplexing phase modulation module modulates the measurement light emitted from the polarization multiplexing interferometer main module. It performs phase modulation according to the two orthogonal polarization states of the measurement light. The first orthogonal polarization state corresponds to the phase modulation for compensating the surface shape of the measured surface, and the second orthogonal polarization state corresponds to the phase modulation for measuring the axial distance from the measured surface 7 to the polarization multiplexing phase modulation module 8.

[0033] The interferogram solving module solves the first interference fringe to obtain the first phase distribution, solves the second interference fringe to obtain the second phase distribution, and further obtains the axial distance from the actual measured surface to the polarization multiplexing phase modulation module based on the second phase distribution.

[0034] The virtual interferometer module simulates the phase distribution corresponding to the ideal measured surface, as well as the axial distance from the ideal measured surface to the polarization multiplexing phase modulation module.

[0035] The measured surface parameter calculation module calculates the surface shape and parameter error of the measured surface based on the ideal and actual phase distribution and the axial distance from the measured surface to the polarization multiplexing phase modulation module.

[0036] This invention utilizes polarization multiplexing to simultaneously and transiently acquire two sets of interferograms. The first interference fringe is used to obtain the phase distribution of the actual measured surface after compensation, and the second interference fringe is used to obtain the axial distance from the actual measured surface to the polarization multiplexing phase modulation module. By combining the virtual interferometer module and the measured surface parameter calculation module, the surface shape and parameter errors of the measured aspheric surface can be obtained. This device contains no moving parts and can achieve transient measurement, thus solving the problem of integration with machine tools. By simultaneously solving for surface shape and parameter errors using the virtual interferometer and the measured surface parameter calculation module, it solves the problem of the inability to measure surface shape and parameters simultaneously. Axial distance measurement using interferometry achieves micrometer-level accuracy, effectively improving parameter measurement accuracy. In summary, this invention achieves simultaneous high-precision transient measurement of surface shape and parameter errors through polarization multiplexing phase modulation, which is beneficial for rapid, high-precision, and highly consistent production testing of large batches of aspheric surfaces.

[0037] Preferably, in the polarization multiplexing interferometer main module, the light emitted by the laser is expanded by a collimating lens and then passes through a beam splitter. Part of the light is reflected by a plane standard mirror as measurement light, and the other part passes through the plane standard mirror and exits from the polarization multiplexing interferometer main module. After modulation by the polarization multiplexing phase modulation module, which consists of a spherical lens 5 and a polarization multiplexing phase modulator 6, two orthogonally polarized measurement beams are generated. The measurement beam with the first orthogonal polarization state corresponds to the phase modulation for compensating the surface shape of the measured surface, and the measurement beam with the second orthogonal polarization state corresponds to the phase modulation for measuring the axial distance from the measured surface to the polarization multiplexing phase modulation module. After the two measurement beams are incident on the measured surface, they are reflected back to the polarization multiplexing phase modulation module and then propagate back to the polarization multiplexing interferometer main module. After passing through the plane standard mirror and being reflected by the beam splitter, they pass through a quarter wavefront and become orthogonally linearly polarized light. After being split by the polarization beam splitter, they are imaged onto the first array detector and the second array detector by the first imaging lens and the second imaging lens, respectively.

[0038] Preferably, in the polarization multiplexing phase modulation module, the phase modulation unit is a polarization multiplexing phase modulator, or a combination of a polarization multiplexing phase modulator and a spherical lens.

[0039] like Figure 2 As shown, a method for operating an apparatus for transient measurement of aspherical surface shape and parameter error includes the following steps:

[0040] (1) Constructing a virtual interferometer: Modeling a virtual interferometer using the nominal parameters of the measured surface, the polarization multiplexing interferometer host module, and the polarization multiplexing phase modulation module;

[0041] (2) Simulate the ideal phase distribution: Use a virtual interferometer to simulate the phase distribution corresponding to the ideal measured surface;

[0042] (3) Simulate the ideal axial distance: The axial distance from the ideal measured surface to the polarization multiplexing phase modulation module is obtained by simulating using a virtual interferometer;

[0043] (4) Constructing the actual interferometer: Using the actual surface under test, the polarization multiplexing interferometer main module, and the polarization multiplexing phase modulation module, construct the actual interferometer and record the first and second interference fringes;

[0044] (5) Measure the actual phase distribution: use the first interference fringe to calculate the first phase distribution, that is, the phase distribution corresponding to the actual measured surface;

[0045] (6) Measure the actual axial distance: use the second interference fringes to solve the second phase distribution, and further calculate the actual axial distance from the measured surface to the polarization multiplexing phase modulation module;

[0046] (7) Calculate the surface shape and parameter error: Based on the ideal and actual phase distribution and the axial distance from the measured surface to the polarization multiplexing phase modulation module, the surface shape and parameter error of the measured surface are calculated.

[0047] Preferably, in step (1), the virtual interferometer modeling is performed using Zemax, CODEV, or Matlab; in step (2), the ideal phase distribution is obtained by ray tracing or angular spectrum propagation simulation.

[0048] Preferably, in step (3), the ideal axial distance is obtained by directly reading the axial distance from the ideal measured surface to the polarization multiplexing phase modulation module in the simulation software.

[0049] Preferably, in step (4), the first interference fringe and the second interference fringe are acquired at the same time by hardware triggering.

[0050] Preferably, in step (5), the first phase distribution is obtained by solving the first interference fringe, and the phase distribution corresponding to the actual measured surface is obtained by using the single-frame interference fringe phase solution method of Fourier method, digital moiré phase shift method, or deep learning method.

[0051] Preferably, in step (6), the second phase distribution is obtained by solving the second interference fringes using the Fourier method, digital moiré phase shifting method, or deep learning method for solving a single-frame interference fringe phase distribution; the axial distance from the actual test surface to the polarization multiplexing phase modulation module is calculated; the second phase distribution is fitted with Zernike and the defocus aberration is extracted and substituted into the virtual interferometer as the optimization target to optimize the axial distance from the test surface to the polarization multiplexing phase modulation module; the optimization result is used as the axial distance from the actual test surface to the polarization multiplexing phase modulation module.

[0052] Preferably, in step (7), based on the ideal and actual phase distribution and the axial distance from the measured surface to the polarization multiplexing phase modulation module, an aspherical parameter error interferometry method combining laser differential confocal positioning is adopted.

[0053] The following details a specific embodiment of the present invention. An apparatus and method for transient measurement of aspherical surface shape and parameter error are implemented as follows:

[0054] Establish a device structure for transient measurement of aspherical surface shape and parameter error, as follows: Figure 1 As shown, the specific implementation method is as follows:

[0055] Polarization multiplexing interferometer main module: In this example, the laser is a helium-neon laser with a wavelength of 632.8nm. The collimating lens expands the laser aperture to 10mm. The beam splitter, plane standard mirror, quarter-wave plate, and polarization beam splitter have an aperture of 15mm. The first imaging lens has a focal length of 15mm. The first array detector has a resolution of 2448×2048. The second imaging lens has a focal length of 15mm. The second array detector has a resolution of 2448×2048.

[0056] Polarization multiplexing phase modulation module: In this example, it is composed of a spatial light modulator and a spherical lens; the first orthogonal polarization state corresponds to the phase modulation of compensating for the surface shape of the measured surface, which is the zero-compensation calculation hologram phase modulation; the second orthogonal polarization state corresponds to the phase modulation of measuring the axial distance from the measured surface to the polarization multiplexing phase modulation module, which is the spherical wave phase modulation that converges to the ideal axial position vertex of the measured surface.

[0057] Interferogram calculation module: In the example, the first phase distribution is obtained by solving the first interference fringe based on deep learning; the second phase distribution is obtained by solving the second interference fringe based on digital moiré phase shifting method. Zernike fitting is performed on the second phase distribution to extract the defocus aberration, which is substituted into the virtual interferometer as the optimization target to optimize the axial distance from the measured surface to the polarization multiplexing phase modulation module. The optimization result is used as the actual axial distance from the measured surface to the polarization multiplexing phase modulation module.

[0058] Virtual Interferometer Module: In this example, the phase distribution corresponding to the ideal measured surface is calculated using ray tracing in the Zemax software, and the axial distance from the ideal measured surface to the polarization multiplexing phase modulation module is directly read.

[0059] Parameter calculation module for the measured surface: In this example, an aspherical parameter error interferometry method combining laser differential confocal positioning is used. Based on the ideal and actual phase distribution and the axial distance from the measured surface to the polarization multiplexing phase modulation module, the surface shape and parameter error of the measured surface are calculated.

[0060] The specific implementation steps are as follows:

[0061] (1) Constructing a virtual interferometer: In this example, based on Zemax software, according to... Figure 1 Virtual interferometer modeling is performed using the nominal parameters of the measured surface, the polarization multiplexing interferometer main module, and the polarization multiplexing phase modulation module.

[0062] (2) Simulation of ideal phase distribution: In the example, the phase distribution corresponding to the ideal measured surface is obtained by simulating the ray tracing method using a virtual interferometer;

[0063] (3) Simulated ideal axial distance: In the example, the ideal axial distance is obtained by directly reading the axial distance from the ideal measured surface to the polarization multiplexing phase modulation module in the Zemax simulation software;

[0064] (4) Constructing an actual interferometer: In the example, according to... Figure 1 An actual interferometer is built using the actual surface under test, the polarization multiplexing interferometer main module, and the polarization multiplexing phase modulation module. Hardware triggering ensures that the first and second interference fringes are acquired and recorded at the same time.

[0065] (5) Measure the actual phase distribution: In the example, the first phase distribution is obtained by solving the first interference fringe based on the deep learning method, that is, the phase distribution corresponding to the actual measured surface;

[0066] (6) Measure the actual axial distance: In the example, the second phase distribution is calculated using the second interference fringes based on the digital moiré phase shifting method; the second phase distribution is fitted with Zernike and the defocus aberration is extracted and substituted into the virtual interferometer as the optimization target to optimize the axial distance from the measured surface to the polarization multiplexing phase modulation module. The optimization result is used as the actual axial distance from the measured surface to the polarization multiplexing phase modulation module.

[0067] (7) Calculate the surface shape and parameter error: In the example, based on the ideal and actual phase distribution and the axial distance from the measured surface to the polarization multiplexing phase modulation module, the surface shape and parameter error of the measured surface are calculated by using the aspherical parameter error interferometry method combined with laser differential confocal positioning.

[0068] The beneficial effects of this invention are as follows:

[0069] 1. This invention does not contain moving parts and can achieve transient measurement, thus solving the problem of integration with machine tools;

[0070] 2. This invention utilizes interference for axial distance measurement, achieving an accuracy at the micrometer level, which effectively improves the accuracy of parameter measurement.

[0071] 3. This invention utilizes a virtual interferometer and a measured surface parameter calculation module to simultaneously solve for surface shape and parameter errors, thus solving the problem that surface shape and parameters cannot be measured simultaneously.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A device for transient measurement of aspherical surface shape and parameter error, characterized in that: It includes: The polarization multiplexing interferometer main module includes a laser, a collimating lens, a beam splitter, a plane standard mirror or a spherical standard mirror, a quarter-wave plate, a polarization beam splitter, a first imaging lens, a first array detector, a second imaging lens, and a second array detector. This module emits collimated or converged measurement light and receives measurement light reflected back to the interferometer main module from the measured surface, separates orthogonally polarized light, and detects the first interference fringes generated by the first orthogonal polarization state and the second interference fringes generated by the second orthogonal polarization state. The polarization multiplexing phase modulation module modulates the measurement light emitted from the polarization multiplexing interferometer main module. It performs phase modulation according to the two orthogonal polarization states of the measurement light. The first orthogonal polarization state corresponds to the phase modulation for compensating the surface shape of the measured surface, and the second orthogonal polarization state corresponds to the phase modulation for measuring the axial distance from the measured surface to the polarization multiplexing phase modulation module. The interferogram solving module solves the first interference fringe to obtain the first phase distribution, solves the second interference fringe to obtain the second phase distribution, and further obtains the axial distance from the actual measured surface to the polarization multiplexing phase modulation module based on the second phase distribution. The virtual interferometer module simulates the phase distribution corresponding to the ideal measured surface, as well as the axial distance from the ideal measured surface to the polarization multiplexing phase modulation module. The measured surface parameter calculation module calculates the surface shape and parameter error of the measured surface based on the ideal and actual phase distribution and the axial distance from the measured surface to the polarization multiplexing phase modulation module.

2. The apparatus for transient measurement of aspherical surface shape and parameter error according to claim 1, characterized in that: In the polarization multiplexing interferometer main module, the light emitted by the laser is expanded by a collimating lens and then passes through a beam splitter. Part of the light is reflected by a plane standard mirror as measurement light, and the other part passes through the plane standard mirror and exits from the polarization multiplexing interferometer main module. After modulation by a polarization multiplexing phase modulation module composed of a spherical lens and a polarization multiplexing phase modulator, two orthogonally polarized measurement beams are generated. The measurement beam with the first orthogonal polarization state corresponds to the phase modulation of compensating for the surface shape of the measured surface, and the measurement beam with the second orthogonal polarization state corresponds to the phase modulation of the axial distance from the measured surface to the polarization multiplexing phase modulation module. After the two measurement beams are incident on the measured surface, they are reflected back to the polarization multiplexing phase modulation module and then propagate back to the polarization multiplexing interferometer main module. After passing through the plane standard mirror and being reflected by the beam splitter, they pass through a quarter wavefront and become orthogonally linearly polarized light. After being split by the polarization beam splitter, they are imaged onto the first array detector and the second array detector by the first imaging lens and the second imaging lens, respectively.

3. The apparatus for transient measurement of aspherical surface shape and parameter error according to claim 2, characterized in that: In the polarization multiplexing phase modulation module, the phase modulation unit is a polarization multiplexing phase modulator, or a combination of a polarization multiplexing phase modulator and a spherical lens.

4. The operating method of the device for transient measurement of aspherical surface shape and parameter error according to claim 1, characterized in that: It includes the following steps: (1) Constructing a virtual interferometer: Modeling a virtual interferometer using the nominal parameters of the measured surface, the polarization multiplexing interferometer host module, and the polarization multiplexing phase modulation module; (2) Simulate the ideal phase distribution: Use a virtual interferometer to simulate the phase distribution corresponding to the ideal measured surface; (3) Simulate the ideal axial distance: The axial distance from the ideal measured surface to the polarization multiplexing phase modulation module is obtained by simulating using a virtual interferometer; (4) Constructing the actual interferometer: Using the actual surface under test, the polarization multiplexing interferometer main module, and the polarization multiplexing phase modulation module, construct the actual interferometer and record the first and second interference fringes; (5) Measure the actual phase distribution: The first phase distribution is obtained by solving the first interference fringe. That is, the phase distribution corresponding to the actual measured surface; (6) Measure the actual axial distance: use the second interference fringes to solve the second phase distribution, and further calculate the actual axial distance from the measured surface to the polarization multiplexing phase modulation module; (7) Calculate the surface shape and parameter error: Based on the ideal and actual phase distribution and the axial distance from the measured surface to the polarization multiplexing phase modulation module, the surface shape and parameter error of the measured surface are calculated.

5. The operating method of the device for transient measurement of aspherical surface shape and parameter error according to claim 4, characterized in that: In step (1), the virtual interferometer is modeled using Zemax, CODEV, or Matlab; in step (2), the ideal phase distribution is simulated using ray tracing or angular spectrum propagation.

6. The operating method of the device for transient measurement of aspherical surface shape and parameter error according to claim 5, characterized in that: In step (3), the ideal axial distance is obtained by directly reading the axial distance from the ideal measured surface to the polarization multiplexing phase modulation module in the simulation software.

7. The operating method of the device for transient measurement of aspherical surface shape and parameter error according to claim 6, characterized in that: In step (4), the first interference fringe and the second interference fringe are acquired at the same time by hardware triggering.

8. The operating method of the device for transient measurement of aspherical surface shape and parameter error according to claim 7, characterized in that: In step (5), the first phase distribution is obtained by solving the first interference fringe. The phase distribution corresponding to the actual measured surface is obtained by using the single-frame interference fringe phase solution method of Fourier method, digital moiré phase shift method, or deep learning method.

9. The operating method of the device for transient measurement of aspherical surface shape and parameter error according to claim 8, characterized in that: In step (6), the second phase distribution is obtained by solving the second interference fringe, using a single-frame interference fringe phase solution method such as Fourier method, digital moiré phase shifting method, or deep learning method. Calculate the axial distance from the actual measured surface to the polarization multiplexing phase modulation module, perform Zernike fitting on the second phase distribution, extract the defocus aberration, and substitute it into the virtual interferometer as the optimization target to optimize the axial distance from the measured surface to the polarization multiplexing phase modulation module. The optimization result is used as the axial distance from the actual measured surface to the polarization multiplexing phase modulation module.

10. The operating method of the device for transient measurement of aspherical surface shape and parameter error according to claim 9, characterized in that: In step (7), based on the ideal and actual phase distribution and the axial distance from the measured surface to the polarization multiplexing phase modulation module, an aspherical parameter error interferometry measurement method combining laser differential confocal positioning is adopted.

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