System aberration self-calibration method and device based on double-interference common-optical-path measurement

Abstract

The application relates to a system aberration self-calibration method and device based on a double-interference common-optical-path measurement, wherein the method comprises the following steps: measuring an optical microstructure surface to be measured by using a double-interference common-optical-path measurement system to obtain phase distribution data and three-dimensional topographic height data; taking a Zernike polynomial as a base function to establish an aberration parameterization model of the double-interference common-optical-path measurement system; taking the phase distribution data as a reference, combining an analytical relationship between a laser interference channel and system aberration parameters, and inversely solving actual aberration coefficient sets of the double-interference common-optical-path measurement system in a current measurement state by using an optimization algorithm; reconstructing an aberration field corresponding to an entire measurement field by using the actual aberration coefficient sets of the double-interference common-optical-path measurement system and combining an analytical relationship between a white light interference channel and system aberration parameters, and point-by-point correcting the three-dimensional topographic height data by using the aberration field. The application can compensate system inherent aberration on line, self-reference and high precision.

Description

Technical Field

[0001] This invention relates to the field of optical precision measurement and instrument manufacturing, and in particular to a system aberration self-calibration method and apparatus based on dual-interference common-path measurement. Background Technology

[0002] Optical interferometry, especially white light interferometry, has become a core method for inspecting the surface morphology of ultra-precision optical components due to its advantages of non-contact operation, high precision, and high resolution. With the urgent need for integrated "processing-measurement" closed-loop manufacturing in high-end manufacturing (such as lithography machines and large-aperture astronomical telescopes), directly integrating interferometry systems into ultra-precision machine tools and other processing equipment to achieve in-situ measurement of workpieces is a key path to overcome manufacturing bottlenecks and improve process efficiency and final accuracy.

[0003] However, in-situ interferometry faces severe challenges from systematic errors. Miniaturized, compact interferometric probes designed to fit the limited installation space of machine tools introduce significant aberrations (such as spherical aberration, coma, and astigmatism) into their optical systems when measuring highly steep, discontinuous, or large off-axis optical microstructure surfaces. These systematic aberrations, related to the measurement position and surface morphology, distort the phase and envelope of the interference signal, leading to a systematic deviation between the surface position detected by the detector and the actual physical position—a phenomenon known as "backlash error"—which can reach hundreds of nanometers in magnitude, severely limiting further improvements in in-situ measurement accuracy.

[0004] Currently, the correction of aberrations in interferometric measurement systems mainly relies on offline calibration and compensation techniques.

[0005] External calibration based on standard references involves offline calibration of the system using high-precision standard parts with known shapes (such as planes, steps, and spheres), establishing a position-error lookup table or fitting an error model. While direct, this method is cumbersome, and the accuracy of the standard parts themselves, the repeatability of clamping, and differences between the calibration environment and the dynamic operating conditions on the machine all introduce additional errors. More importantly, once the measurement system is installed on the machine tool, its optical state may drift due to factors such as temperature and stress, and external calibration cannot achieve online sensing and compensation for such drifts.

[0006] The analytical compensation method based on the system optical model: By accurately modeling the interference optical path (including the light source, lens group, beam splitter, detector, etc.), the system aberration function is theoretically derived and used to correct the measurement results. However, this method is extremely sensitive to the manufacturing and assembly tolerances of optical components, making it difficult to accurately obtain the actual state parameters of the integrated system. Furthermore, the model usually cannot cover all nonlinear and environmental coupling effects, limiting its applicability in complex real-world environments.

[0007] The aforementioned existing methods all suffer from a fundamental limitation: they are essentially "open-loop" calibrations, meaning they are calibrated only once before or outside of the measurement process, and cannot perform real-time sensing and closed-loop correction of the system's own potentially time-varying aberrations during the measurement process. This makes it difficult to consistently guarantee measurement accuracy during long-term operation or environmental changes. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a system aberration self-calibration method and device based on dual-interference common optical path measurement, which can invert and compensate for the inherent aberrations of the system online, self-referenced, and with high precision.

[0009] The technical solution adopted by this invention to solve its technical problem is: to provide a system aberration self-calibration method based on dual-interference common-path measurement, comprising the following steps:

[0010] A dual-interference common-path measurement system is used to measure the surface of the optical microstructure under test to obtain phase distribution data and three-dimensional morphology height data. The dual-interference common-path measurement system includes a laser interference channel and a white light interference channel. The laser interference channel is used to acquire the phase distribution data, and the white light interference channel is used to acquire the three-dimensional morphology height data.

[0011] Using Zernike polynomials as basis functions, an aberration parameterization model of the dual-interference common-path measurement system is established to obtain the analytical relationship between the laser interference channel and the system aberration parameters, as well as the analytical relationship between the white light interference channel and the system aberration parameters.

[0012] Based on the phase distribution data, and combined with the analytical relationship between the laser interference channel and the system aberration parameters, the actual set of aberration coefficients of the dual-interference common-path measurement system under the current measurement state is obtained by inversion through optimization algorithm;

[0013] Using the actual set of aberration coefficients of the dual-interference common-path measurement system, and combining the analytical relationship between the white light interference channel and the system aberration parameters, an aberration field corresponding to the entire measurement field of view is reconstructed. The aberration field is then used to correct the three-dimensional topography height data point by point.

[0014] The method employs a dual-interference common-path measurement system to measure the surface of the optical microstructure under test, and after obtaining phase distribution data and three-dimensional topographic height data, it also includes synchronous mapping of the phase distribution data and the three-dimensional topographic height data through timestamps or spatial registration.

[0015] The system aberration self-calibration method based on dual-interference common-path measurement further includes preprocessing the phase distribution data, the preprocessing including:

[0016] The phase distribution data is subjected to phase unwrapping processing;

[0017] The phase distribution data after phase unwrapping is subjected to low-order term removal processing.

[0018] The analytical relationship between the laser interference channel and the system aberration parameters is expressed as a laser phase expression using Zernike polynomial expansion within a unit circular aperture, as follows: ,in, For laser phase, The polar coordinates of the measurement point. The first laser interference channel Zernike basis functions For the first Aberration coefficients, This represents the number of Zernike basis functions.

[0019] The analytical relationship between the white light interference channel and the system aberration parameters is expressed as follows: ,in, This is the three-dimensional topographic height data. The polar coordinates of the measurement point. The first white light interference channel Zernike basis functions For the first Aberration coefficients, The number of Zernike basis functions. is the laser wavelength.

[0020] Based on the phase distribution data and combined with the analytical relationship between the laser interference channel and the system aberration parameters, the actual set of aberration coefficients of the dual-interference common-path measurement system under the current measurement state is obtained by inversion through an optimization algorithm, specifically including:

[0021] The phase distribution data is organized into a column vector. The values ​​of the Zernike basis functions corresponding to each measurement point are arranged into a matrix. The analytical relationship between the laser interference channel and the system aberration parameters is transformed into a matrix equation. ,in, The vector of aberration coefficients to be inverted;

[0022] Based on the matrix equation Construct an inversion objective function to find the optimal aberration coefficient vector. This minimizes the error between the phase distribution data obtained from the matrix equation and the actual phase distribution data.

[0023] The least squares method is used as the optimization algorithm to solve the inversion objective function, and the inverted aberration coefficient vector is obtained. The expression: .

[0024] The aberration field corresponding to the entire measurement field of view is reconstructed by utilizing the actual aberration coefficient set of the dual-interference common-path measurement system and combining the analytical relationship between the white light interference channel and the system aberration parameters. The aberration field is then used to correct the three-dimensional topographic height data point-by-point, specifically including:

[0025] The aberration coefficient vector Substituting the aberration coefficients into the analytical relationship between the white light interference channel and the system aberration parameters, the aberration field is obtained. ;

[0026] The equivalent height error is calculated based on the aberration field, and the calculation method is as follows: ,in, This is the equivalent height error;

[0027] The equivalent height error is used to correct the three-dimensional topographic height data point by point. The calculation method for the correction is as follows: ,in, The corrected 3D topographic height data, The height data refers to the three-dimensional shape.

[0028] The technical solution adopted by this invention to solve its technical problem is: to provide a system aberration self-calibration device based on dual-interference common-path measurement, comprising:

[0029] The measurement module is used to measure the surface of the optical microstructure under test using a dual-interference common-path measurement system to obtain phase distribution data and three-dimensional morphology height data. The dual-interference common-path measurement system includes a laser interference channel and a white light interference channel. The laser interference channel is used to acquire the phase distribution data, and the white light interference channel is used to acquire the three-dimensional morphology height data.

[0030] A module is established to build an aberration parameterization model of the dual-interference common-path measurement system using Zernike polynomials as basis functions, and to obtain the analytical relationship between the laser interference channel and the system aberration parameters, as well as the analytical relationship between the white light interference channel and the system aberration parameters.

[0031] The inversion solution module is used to use the phase distribution data as a reference, combined with the analytical relationship between the laser interference channel and the system aberration parameters, to invert and solve the actual set of aberration coefficients of the dual-interference common optical path measurement system under the current measurement state through an optimization algorithm;

[0032] The correction module is used to reconstruct the aberration field corresponding to the entire measurement field of view by using the actual aberration coefficient set of the dual-interference common-path measurement system and the analytical relationship between the white light interference channel and the system aberration parameters, and to use the aberration field to correct the three-dimensional topography height data point by point.

[0033] The technical solution adopted by the present invention to solve its technical problem is: to provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, it implements the steps of the above-mentioned system aberration self-calibration method based on dual-interference common-path measurement.

[0034] The technical solution adopted by the present invention to solve its technical problem is: to provide a computer-readable storage medium on which a computer program is stored, wherein when the computer program is executed by a processor, the steps of the above-mentioned system aberration self-calibration method based on dual-interference common optical path measurement are implemented.

[0035] Beneficial effects

[0036] Due to the adoption of the above-mentioned technical solution, this invention has the following advantages and positive effects compared with the prior art: This invention uses Zernike polynomial and other basis functions to parameterize the wavefront aberration of the system, establishes an error propagation model between aberration parameters and laser interference phase readings and white light interference morphology readings, and utilizes the characteristic that laser interference signals are extremely sensitive to optical path changes (up to sub-nanometer level) to use the measured phase distribution as a high-precision reference benchmark. By solving the established error propagation model, the current aberration coefficient of the system is calculated in reverse from the measurement data of the workpiece under test (without the need for standard parts) in a single test. Based on the aberration coefficient, the original white light interference morphology data is compensated for spatial variation in real time and point by point. The whole process does not require external standard parts and can sense the system state drift in real time, realize closed-loop compensation, and ensure long-term measurement reliability. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the dual-interference common-optical-path measurement system in the first embodiment of the present invention;

[0038] Figure 2 This is a flowchart of the system aberration self-calibration method based on dual-interference common optical path measurement according to the first embodiment of the present invention. Detailed Implementation

[0039] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0040] The first embodiment of the present invention relates to a system aberration self-calibration method based on dual-interference common-path measurement. Before implementing the method of this embodiment, it is necessary to build a system such as... Figure 1 The diagram shows a common-path dual-interference measurement system. This system integrates core components such as a fiber laser (laser interference source), a white light source, a polarizing beam splitter, a dichroic mirror, a sleeve objective lens, a color CMOS camera, and a spectrometer, forming a dual-measurement channel with a shared optical path. Within the same optical probe, it integrates a laser interference channel and a white light interference channel, sharing most of the optical path components. The laser interference channel is used to acquire highly sensitive phase information, while the white light interference channel is used to acquire absolute three-dimensional surface topography information.

[0041] like Figure 2 As shown, the system aberration self-calibration method based on dual-interference common-path measurement in this embodiment includes the following steps:

[0042] Step 1: Use a dual-interference common-path measurement system to measure the surface of the optical microstructure under test and obtain phase distribution data. and 3D topographic height data .in, The wavelength of the laser. This represents the true surface height of the optical microstructure being tested.

[0043] To ensure spatial consistency in subsequent analysis, this embodiment can also achieve synchronous mapping between the phase distribution data and the three-dimensional topographic height data through timestamps or spatial registration, i.e.: .

[0044] This embodiment can also preprocess the phase distribution data to purify the effective signals related to aberrations. Specific preprocessing methods include:

[0045] Phase unwrapping processing of the phase distribution data can be expressed as follows: ,in, For phase unwrapping processing operations, Phase distribution data after phase unwrapping;

[0046] The phase distribution data after phase unwrapping is subjected to low-order term removal processing, which can be expressed as: ,in, The effective phase distribution data is obtained after removing lower-order terms. These are the coefficients of the lower-order terms obtained through least-squares fitting.

[0047] Step 2: Using Zernike polynomials as basis functions, establish the aberration parameterization model of the dual-interference common-path measurement system to obtain the analytical relationship between the laser interference channel and the system aberration parameters, as well as the analytical relationship between the white light interference channel and the system aberration parameters.

[0048] This step uses Zernike polynomials as basis functions to transform complex system aberrations (wavefront distortion) into a quantifiable mathematical model. Its core logic is to decompose the aberrations into a linear combination of standard basis functions. Within a unit circular aperture, the laser phase data can be expressed as a Zernike polynomial expansion, i.e.: ,in, For laser phase, The polar coordinates of the measurement point. The first laser interference channel Zernike basis functions For the first Aberration coefficients, Let be the number of Zernike basis functions. The above equation indicates that the effective change in the laser phase is due to various aberrations (from...). (Quantitative) The result obtained by superimposing Zernike basis functions is precisely the quantitative description of how aberrations affect the laser phase by the error propagation model. Based on the above equation, the analytical relationship between the laser interference channel and the system aberration parameters is obtained. The analytical relationship between the white light interference channel and the system aberration parameters can be expressed as: ,in, This is the three-dimensional topographic height data. The wavelength of the laser. The first white light interference channel One Zernike basis function.

[0049] Step 3: Based on the phase distribution data, and combined with the analytical relationship between the laser interference channel and the system aberration parameters, the actual set of aberration coefficients of the dual-interference common-path measurement system under the current measurement state is obtained by inversion through optimization algorithm.

[0050] Since the analytical relationship between the laser interference channel and the system aberration parameters obtained in step 2 is a continuous function, while the phase distribution data collected in step 1 is discrete measurement point data, it is necessary to adapt the data format first in order to prepare for substituting it into the analytical relationship between the laser interference channel and the system aberration parameters for solving.

[0051] In this implementation, the effective phase distribution data is organized into a column vector. The values ​​of the Zernike basis functions corresponding to each measurement point are then organized into a matrix. , where the matrix The i-th row corresponds to the i-th measurement point, and the n-th column corresponds to the value of the n-th Zernike basis function. Then, the analytical relationship between the laser interferometry channel and the system aberration parameters is transformed into a matrix equation. ,in, Let be the aberration coefficient vector to be inverted.

[0052] The above matrix equation The essence is that the observed values ​​are known. sum matrix Solving for the unknown aberration coefficient vector This is a system of linear equations. Since the number of measurement points is usually much larger than the number of Zernike basis functions, this system of linear equations is overdetermined and cannot be solved directly. Therefore, an optimization objective function needs to be constructed based on the physical meaning of the matrix equations. The objective function aims to find the optimal aberration coefficient vector. The objective function aims to minimize the error between the phase distribution data obtained from the matrix equation and the actual phase distribution data. This objective function can be expressed as: ,in, It is the L2 norm. The sum of squared errors is the physical meaning of the sum of the deviations between the phase predicted by the analytical relationship between the laser interference channel and the system aberration parameters and the actual measured phase.

[0053] This implementation uses the least squares method as the optimization algorithm. Its solution process relies entirely on the matrix equation form of the analytical relationship between the laser interferometer channel and the system aberration parameters. The specific derivation is as follows:

[0054] For the objective function Seeking information about The partial derivative of is given, and set to 0, that is: The analytical expression for the optimal solution is obtained by rearranging: This is the actual set of aberration coefficients of the dual-interference common-path measurement system under the current measurement state. The physical meaning of this formula is the inverse operation of the analytical relationship between the laser interference channel and the system aberration parameters, from the measured phase... Aberration coefficients are extracted from the data to achieve the inversion of aberration parameters from the measurement data.

[0055] Step 4: Using the actual aberration coefficient set of the dual-interference common-path measurement system, and combining the analytical relationship between the white light interference channel and the system aberration parameters, reconstruct the aberration field corresponding to the entire measurement field of view, and use the aberration field to correct the three-dimensional topography height data point by point.

[0056] The aberration coefficient vector obtained in this step Substituting the aberration coefficients into the analytical relationship between the white light interference channel and the system aberration parameters, the aberration field can be obtained. Then, based on the aberration field... The equivalent height error is calculated as follows: ,in, This is the equivalent height error. Then, the equivalent height error is used to correct the 3D topography height data point by point, thus eliminating the backlash error caused by system aberrations, and finally outputting a calibrated high-precision surface topography. The calculation method for correction is as follows: ,in, This is the corrected 3D topographic height data.

[0057] It is easy to see that this invention uses Zernike polynomials and other basis functions to parameterize the wavefront aberrations of the system, establishes an error propagation model between aberration parameters and laser interference phase readings and white light interference topography readings, and utilizes the characteristic that laser interference signals are extremely sensitive to changes in optical path (down to the sub-nanometer level) to use the measured phase distribution as a high-precision reference. By solving the established error propagation model, the current aberration coefficients of the system are calculated in reverse from the measurement data of a single workpiece under test (without the need for standard parts), and the original white light interference topography data is compensated for spatial variation in real time and point by point based on the aberration coefficients. The entire process does not require external standard parts and can detect system state drift in real time to achieve closed-loop compensation, ensuring long-term measurement reliability.

[0058] A second embodiment of the present invention relates to a system aberration self-calibration device based on dual-interference common-path measurement, comprising:

[0059] The measurement module is used to measure the surface of the optical microstructure under test using a dual-interference common-path measurement system to obtain phase distribution data and three-dimensional morphology height data. The dual-interference common-path measurement system includes a laser interference channel and a white light interference channel. The laser interference channel is used to acquire the phase distribution data, and the white light interference channel is used to acquire the three-dimensional morphology height data.

[0060] A module is established to build an aberration parameterization model of the dual-interference common-path measurement system using Zernike polynomials as basis functions, and to obtain the analytical relationship between the laser interference channel and the system aberration parameters, as well as the analytical relationship between the white light interference channel and the system aberration parameters.

[0061] The inversion solution module is used to use the phase distribution data as a reference, combined with the analytical relationship between the laser interference channel and the system aberration parameters, to invert and solve the actual set of aberration coefficients of the dual-interference common optical path measurement system under the current measurement state through an optimization algorithm;

[0062] The correction module is used to reconstruct the aberration field corresponding to the entire measurement field of view by using the actual aberration coefficient set of the dual-interference common-path measurement system and the analytical relationship between the white light interference channel and the system aberration parameters, and to use the aberration field to correct the three-dimensional topography height data point by point.

[0063] The measurement module includes a synchronization unit, which is used to achieve synchronous mapping of the phase distribution data and the three-dimensional topographic height data through timestamps or spatial registration.

[0064] The system aberration self-calibration device includes a preprocessing module, which includes:

[0065] A phase unwrapping unit is used to perform phase unwrapping processing on the phase distribution data;

[0066] The low-order term removal unit is used to perform low-order term removal processing on the phase distribution data after phase unwrapping.

[0067] The analytical relationship between the laser interference channel and the system aberration parameters is expressed as follows: ,in, For laser phase, The polar coordinates of the measurement point. The first laser interference channel Zernike basis functions For the first Aberration coefficients, This represents the number of Zernike basis functions.

[0068] The analytical relationship between the white light interference channel and the system aberration parameters is expressed as follows: ,in, This is the three-dimensional topographic height data. The polar coordinates of the measurement point. The first white light interference channel Zernike basis functions For the first Aberration coefficients, The number of Zernike basis functions. is the laser wavelength.

[0069] The inversion solution module includes:

[0070] The transformation unit is used to organize the phase distribution data into a column vector. The values ​​of the Zernike basis functions corresponding to each measurement point are arranged into a matrix. The analytical relationship between the laser interference channel and the system aberration parameters is transformed into a matrix equation. ,in, The vector of aberration coefficients to be inverted;

[0071] Construction unit, used for constructing based on the matrix equation Construct an inversion objective function to find the optimal aberration coefficient vector. This minimizes the error between the phase distribution data obtained from the matrix equation and the actual phase distribution data.

[0072] The solution unit is used to solve the inversion objective function using the least squares method as the optimization algorithm to obtain the inverted aberration coefficient vector. The expression: .

[0073] The correction module includes:

[0074] Aberration field calculation unit, used to calculate the aberration coefficient vector Substituting the aberration coefficients into the analytical relationship between the white light interference channel and the system aberration parameters, the aberration field is obtained. ;

[0075] The equivalent height error calculation unit is used to calculate the equivalent height error based on the aberration field. The calculation method is as follows: ,in, This is the equivalent height error;

[0076] The correction unit is used to correct the three-dimensional topographic height data point by point using the equivalent height error. The calculation method for the correction is as follows: ,in, The corrected 3D topographic height data, The height data refers to the three-dimensional shape.

[0077] The third embodiment of the present invention relates to an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the system aberration self-calibration method based on dual-interference common-path measurement of the first embodiment.

[0078] The fourth embodiment of the present invention relates to a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the system aberration self-calibration method based on dual-interference common-path measurement of the first embodiment.

[0079] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0080] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0081] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction methods implemented in a process. Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0082] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0083] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A system aberration self-calibration method based on dual-interference common-path measurement, characterized in that, Includes the following steps: A dual-interference common-path measurement system is used to measure the surface of the optical microstructure under test to obtain phase distribution data and three-dimensional morphology height data. The dual-interference common-path measurement system includes a laser interference channel and a white light interference channel. The laser interference channel is used to acquire the phase distribution data, and the white light interference channel is used to acquire the three-dimensional morphology height data. Using Zernike polynomials as basis functions, an aberration parameterization model of the dual-interference common-path measurement system is established to obtain the analytical relationship between the laser interference channel and the system aberration parameters, as well as the analytical relationship between the white light interference channel and the system aberration parameters. Based on the phase distribution data, and combined with the analytical relationship between the laser interference channel and the system aberration parameters, the actual set of aberration coefficients of the dual-interference common-path measurement system under the current measurement state is obtained by inversion through optimization algorithm; Using the actual set of aberration coefficients of the dual-interference common-path measurement system, and combining the analytical relationship between the white light interference channel and the system aberration parameters, an aberration field corresponding to the entire measurement field of view is reconstructed. The aberration field is then used to correct the three-dimensional topography height data point by point.

2. The system aberration self-calibration method based on dual-interference common-path measurement according to claim 1, characterized in that, The method employs a dual-interference common-path measurement system to measure the surface of the optical microstructure under test, and after obtaining phase distribution data and three-dimensional topographic height data, it also includes synchronous mapping of the phase distribution data and the three-dimensional topographic height data through timestamps or spatial registration.

3. The system aberration self-calibration method based on dual-interference common-path measurement according to claim 1, characterized in that, It also includes preprocessing the phase distribution data, the preprocessing including: The phase distribution data is subjected to phase unwrapping processing; The phase distribution data after phase unwrapping is subjected to low-order term removal processing.

4. The system aberration self-calibration method based on dual-interference common-path measurement according to claim 1, characterized in that, The analytical relationship between the laser interference channel and the system aberration parameters is expressed as follows: ,in, For laser phase, The polar coordinates of the measurement point. For the first laser interference channel One Zernike basis function For the first Aberration coefficients, This represents the number of Zernike basis functions.

5. The system aberration self-calibration method based on dual-interference common-path measurement according to claim 1, characterized in that, The analytical relationship between the white light interference channel and the system aberration parameters is expressed as follows: ,in, This is the three-dimensional topographic height data. The polar coordinates of the measurement point. The first white light interference channel One Zernike basis function For the first Aberration coefficients, The number of Zernike basis functions. is the laser wavelength.

6. The system aberration self-calibration method based on dual-interference common-path measurement according to claim 1, characterized in that, Based on the phase distribution data and combined with the analytical relationship between the laser interference channel and the system aberration parameters, the actual set of aberration coefficients of the dual-interference common-path measurement system under the current measurement state is obtained by inversion through an optimization algorithm, specifically including: The phase distribution data is organized into a column vector. The values ​​of the Zernike basis functions corresponding to each measurement point are arranged into a matrix. The analytical relationship between the laser interference channel and the system aberration parameters is transformed into a matrix equation. ,in, The vector of aberration coefficients to be inverted; Based on the matrix equation Construct an inversion objective function to find the optimal aberration coefficient vector. This minimizes the error between the phase distribution data obtained from the matrix equation and the actual phase distribution data. The least squares method is used as the optimization algorithm to solve the inversion objective function, and the inverted aberration coefficient vector is obtained. The expression: .

7. The system aberration self-calibration method based on dual-interference common-path measurement according to claim 6, characterized in that, The aberration field corresponding to the entire measurement field of view is reconstructed by utilizing the actual aberration coefficient set of the dual-interference common-path measurement system and combining the analytical relationship between the white light interference channel and the system aberration parameters. The aberration field is then used to correct the three-dimensional topographic height data point-by-point, specifically including: The aberration coefficient vector Substituting the aberration coefficients into the analytical relationship between the white light interference channel and the system aberration parameters, the aberration field is obtained. ; The equivalent height error is calculated based on the aberration field, and the calculation method is as follows: ,in, For equivalent height error, The wavelength of the laser; The equivalent height error is used to correct the three-dimensional topographic height data point by point. The calculation method for the correction is as follows: ,in, The corrected 3D topographic height data, This refers to the height data of the three-dimensional shape.

8. A system aberration self-calibration device based on dual-interference common-path measurement, characterized in that, include: The measurement module is used to measure the surface of the optical microstructure under test using a dual-interference common-path measurement system to obtain phase distribution data and three-dimensional morphology height data. The dual-interference common-path measurement system includes a laser interference channel and a white light interference channel. The laser interference channel is used to acquire the phase distribution data, and the white light interference channel is used to acquire the three-dimensional morphology height data. A module is established to build an aberration parameterization model of the dual-interference common-path measurement system using Zernike polynomials as basis functions, and to obtain the analytical relationship between the laser interference channel and the system aberration parameters, as well as the analytical relationship between the white light interference channel and the system aberration parameters. The inversion solution module is used to use the phase distribution data as a reference, combined with the analytical relationship between the laser interference channel and the system aberration parameters, to invert and solve the actual set of aberration coefficients of the dual-interference common optical path measurement system under the current measurement state through an optimization algorithm; The correction module is used to reconstruct the aberration field corresponding to the entire measurement field of view by using the actual aberration coefficient set of the dual-interference common-path measurement system and combining the analytical relationship between the white light interference channel and the system aberration parameters, and to use the aberration field to correct the three-dimensional topography height data point by point.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the system aberration self-calibration method based on dual-interference common-path measurement as described in any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the system aberration self-calibration method based on dual-interference common-path measurement as described in any one of claims 1-7.

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