Complex surface multi-parameter interference and pulsed ion beam measurement processing integrated method device

Abstract

This invention relates to an integrated method and apparatus for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces, belonging to the field of precision optical equipment technology. The method includes: fixing the optical element to be processed in a transferable clamping assembly, maintaining their relative orientation throughout the process; establishing a workpiece coordinate system and calibrating its transformation relationship with the measurement and processing coordinate systems; performing common aperture measurement through a shared optical path and a broadband, single-frequency interferometric channel of the measured aperture, acquiring optical signals, and obtaining measurement parameters based on a virtual-real fusion interferometry model; mapping the measurement parameters to the workpiece coordinate system based on the transformation relationship to generate surface state data, comparing this data with target data to obtain the target removal amount distribution; and solving for processing parameters using a pre-calibrated single-pulse removal function and coordinate transformation matrix to perform pulsed ion beam material removal. This invention can reduce errors introduced by repeated clamping and environmental switching, achieving closed-loop correction for multi-parameter measurement and deterministic processing of complex optical surfaces.

Description

Technical Field

[0001] This invention relates to the field of precision optical equipment technology, and in particular to an integrated method and apparatus for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces. Background Technology

[0002] With the rapid development of high-power lasers, space optics, and advanced lithography, aspherical, freeform, and complex optical components with functional coatings are widely used. The surface accuracy, coating thickness uniformity, optical constant stability, and surface defect level of such optical components directly determine the wavefront quality, spectral characteristics, and damage resistance of the optical system. Any deviation from these parameters may cause wavefront distortion, spectral shift, or local field intensity enhancement. Therefore, stringent requirements are placed on manufacturing precision at the nanometer or even sub-nanometer level.

[0003] Currently, parameter detection and material correction for complex optical surfaces generally adopt a separate operation mode. At the measurement end, broadband interferometry equipment is used to obtain information on film thickness and optical constants, while single-frequency interferometry equipment is used to obtain surface shape and surface defect characteristics. The two types of equipment are independent of each other, using their own clamping references and coordinate systems. The multiple sets of parameters measured lack a unified spatial coordinate mapping relationship, making it impossible to achieve precise matching of the spatial positions of surface shape, film thickness, and defects. The measurement results are difficult to directly convert into processing instructions with spatial correspondence.

[0004] On the processing side, existing optical components typically employ a discrete process of "offline measurement—disassembly and handling—re-clamping—processing—disassembly and measurement again." The measuring and processing equipment use different coordinate references and clamping methods. Multiple workpiece transfers and repeated clamping introduce significant positioning errors, which account for a very high percentage in micro- and nano-scale correction scenarios, directly leading to decreased processing accuracy and reduced convergence efficiency. Furthermore, in this discrete mode, measurement and processing parameters require manual conversion and offline transmission, creating a data link gap and preventing seamless integration of measurement results into processing instructions, further restricting processing determinism.

[0005] In summary, the existing discrete operation mode has core technical bottlenecks such as inconsistent coordinate references, spatial mismatch of multi-parameter measurements, and broken data links between measurement and processing, which cannot meet the high-precision and high-determinism multi-parameter collaborative correction requirements of complex optical surfaces. Summary of the Invention

[0006] Therefore, it is necessary to provide an integrated method and apparatus for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces, which can effectively reduce coordinate errors introduced by repeated clamping and improve the processing determinism and accuracy of multi-parameter collaborative correction in the application scenario of nanometer-level precision correction of complex optical surfaces.

[0007] A method integrating multi-parameter interferometry and pulsed ion beam measurement and processing for complex surfaces, the method comprising: Step 201: Fix the optical element to be processed to the transferable clamping assembly. The relative position of the optical element to be processed and the transferable clamping assembly remains unchanged throughout the measurement, transfer and processing process. Step 202: Establish a workpiece coordinate system on the transferable clamping assembly, calibrate the first coordinate transformation matrix between the workpiece coordinate system and the measurement coordinate system, and calibrate the second coordinate transformation matrix between the workpiece coordinate system and the machining coordinate system; Step 203: By sharing the broadband interference channel and the single-frequency interference channel of the optical path segment and the aperture under test, perform common aperture interferometry on the optical element to be processed, collect broadband interference signals and single-frequency interference signals respectively, and then obtain measurement parameters based on the virtual-real fusion interference model; Step 204: Based on the first coordinate transformation matrix, the measurement parameters are uniformly mapped to the workpiece coordinate system to generate surface state data with spatial coordinate correspondence; the surface state data is compared with the target surface data to obtain the target removal amount distribution in the workpiece coordinate system. Step 205: Based on the pre-calibrated single-pulse removal function and the target removal amount distribution, and combined with the second coordinate transformation matrix, the processing parameters in the processing coordinate system are obtained; based on the processing parameters, pulsed ion beam material removal is performed on the optical element to be processed.

[0008] On the other hand, a complex surface multi-parameter interferometry and pulsed ion beam measurement and processing integrated device is also provided. The device includes: a multi-parameter interferometry chamber, a buffer chamber, a pulsed ion beam processing chamber, a transferable clamping assembly, and a control and data processing system. The buffer chamber is located between the multi-parameter interferometric measurement chamber and the pulsed ion beam processing chamber, and its two sides are selectively connected to the multi-parameter interferometric measurement chamber and the pulsed ion beam processing chamber through isolation valves, respectively, so as to realize the state-maintaining transfer of the workpiece between the measurement station and the processing station while maintaining the clamping state. The transferable clamping assembly is used to carry the optical element to be processed and can move between the multi-parameter interferometry chamber, the buffer chamber and the pulsed ion beam processing chamber. The relative position of the optical element to be processed and the transferable clamping assembly remains fixed throughout the measurement, transfer and processing process. The control and data processing system is communicatively connected to the multi-parameter interferometric measurement chamber, the buffer chamber, the pulsed ion beam processing chamber, and the transferable clamping assembly, and is used to perform measurement parameter inversion, coordinate mapping, target removal amount calculation, processing parameter solving, transfer interlock control, and processing closed-loop feedback control.

[0009] The aforementioned integrated method and apparatus for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces uses a unified workpiece coordinate system established in a single setup as the core reference. By calibrating the transformation relationship between the workpiece coordinate system and the measurement and processing coordinate systems, it eliminates coordinate mismatch errors caused by repeated setup and disassembly from both physical setup and mathematical mapping dimensions, providing a unified spatial reference for data alignment throughout the entire process. Under this reference, broadband and single-frequency interferometry channels share the measured optical path and the measured aperture to perform common aperture detection. Combined with a virtual-real fusion interferometry model, measurement parameters are obtained, avoiding the reference deviation of discrete equipment and achieving spatial matching of multiple parameters from the same source. After coordinate mapping, the measurement parameters directly generate the target removal amount distribution, and the pulse processing parameters are solved by combining the calibrated single-pulse removal function, achieving seamless conversion from measurement parameters to processing commands. These core steps work together to connect the measurement, data processing, and processing processes in a unified workpiece coordinate system, effectively reducing the comprehensive errors introduced by repeated setup and reference transformation, and improving the processing determinism and accuracy of multi-parameter collaborative correction for complex optical surfaces. Attached Figure Description

[0010] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention, and those skilled in the art can obtain other related drawings based on these drawings without creative effort.

[0011] Figure 1 This is a flowchart illustrating an integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces in one embodiment. Figure 2 This is a schematic diagram of the coordinate unification mapping logic in one embodiment; Figure 3 This is a structural block diagram of an integrated device for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces in one embodiment; Figure 4 This is a structural block diagram of a multi-parameter interferometry chamber in one embodiment; Figure 5 This is a block diagram of the buffer compartment's state transfer and coordinate maintenance in one embodiment; Figure 6 This is a structural block diagram of a pulsed ion beam processing chamber in one embodiment.

[0012] Explanation of reference numerals in the attached figures: The system includes a multi-parameter interferometric measurement chamber 110, a buffer chamber 120, a pulsed ion beam processing chamber 130, a control and data processing system 140, a transferable clamping assembly 150, a broadband light source 111, a single-frequency light source 112, an optical path switching and collimation module 114, a common aperture interferometry module 115, a spectral dispersion imaging module 116, an interferogram imaging module 117, a precision displacement and environmental calibration module 118, a first isolation valve 121, a second isolation valve 122, an independent gas pumping and filling unit 123, a temperature control unit 124, a transfer and locking unit 125, a pulsed ion source 131, a pulse power supply and triggering module 132, an ion optics and beam monitoring module 133, a workpiece scanning and positioning module 134, a processing controller 135, a vacuum process unit 136, and a coordinate transformation matrix solving and error compensation module 143.

[0013] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0015] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0016] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0017] It is understood that the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0018] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0019] Example 1 like Figure 1 As shown, a method integrating multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces is provided, including the following steps: Step 201: Fix the optical element to be processed to the transferable clamping assembly. The relative position of the optical element to be processed and the transferable clamping assembly remains unchanged throughout the measurement, transfer and processing process.

[0020] In this step, the workpiece is fixed to the bearing clamping assembly at once and its relative pose remains constant throughout the entire process, thus locking the spatial positioning reference of the workpiece at the physical structure level. This reference is the common physical premise for subsequent coordinate calibration, multi-station measurement and processing, and return for re-measurement. It forms a synergistic relationship with subsequent coordinate transformation, common aperture measurement, parameter solving and other steps, ensuring that all operations in the entire process are carried out based on the same clamping state. This directly eliminates the positioning error introduced by multiple disassembly and re-clamping in the traditional discrete process, provides a basic positioning guarantee for nanometer-level precision correction, indirectly reduces the number of processing iterations, and improves the overall processing convergence efficiency.

[0021] Step 202: Establish a workpiece coordinate system on the transferable clamping assembly, calibrate the first coordinate transformation matrix between the workpiece coordinate system and the measurement coordinate system, and calibrate the second coordinate transformation matrix between the workpiece coordinate system and the machining coordinate system.

[0022] In this step, a workpiece coordinate system independent of the measuring and processing equipment is established using the clamping assembly as a carrier. The transformation mapping relationship between the workpiece coordinate system and the coordinate systems of the two types of equipment is obtained through calibration, realizing the common origin and unification of multiple coordinate systems from a mathematical perspective. This step provides a unified mathematical benchmark for the coordinate mapping of measurement parameters and the coordinate transformation of processing parameters, directly solving the core problem of inconsistent coordinate benchmarks of discrete equipment. This allows measurement results to be directly converted into processing instructions, avoiding the additional errors and delays introduced by manual coordinate registration.

[0023] Step 203: By sharing the broadband interference channel and the single-frequency interference channel of the optical path segment and the aperture under test, common aperture interferometry is performed on the optical element to be processed. Broadband interference signals and single-frequency interference signals are collected respectively, and then the measurement parameters are obtained based on the virtual-real fusion interference model.

[0024] In this step, a common-aperture optical path design is adopted to ensure that the two types of interferometric measurements share the same measured optical path and measured aperture, physically guaranteeing the common origin of the spatial reference for multi-dimensional measurements. Combined with a virtual-real fusion interferometric model, system errors and environmental disturbances are corrected, enabling the joint inversion of multiple optical parameters. The multi-dimensional measurement parameters output in this step serve as the input source for subsequent surface state data generation. The common-aperture design provides physical support for subsequent spatial coordinate matching of multiple parameters, and, in conjunction with the coordinate transformation matrix in step 202, enables precise spatial positioning of the measurement parameters. This overcomes the shortcomings of spatial mismatch in multi-parameter measurements from discrete measurement devices, and simultaneously reduces the ambiguity of inversion for a single measurement quantity through joint inversion of multiple physical quantities, improving the consistency and accuracy of multi-parameter detection.

[0025] Step 204: Based on the first coordinate transformation matrix, the measurement parameters are uniformly mapped to the workpiece coordinate system to generate surface state data with spatial coordinate correspondence; the surface state data is compared with the target surface data to obtain the target removal amount distribution in the workpiece coordinate system.

[0026] In this step, based on the first coordinate transformation matrix, measurement parameters of different dimensions are uniformly mapped to the workpiece coordinate system, achieving spatial coordinate alignment of multiple parameters. Through comparison and calculation with the target surface data, the measured error data is transformed into target removal amount data that can be used for machining, providing target input for solving machining parameters. This step can directly achieve seamless conversion from measurement parameters to machining targets, eliminating the gap between offline data processing and manual matching in discrete modes, and improving the efficiency and accuracy of machining command generation.

[0027] Step 205: Based on the pre-calibrated single-pulse removal function and the target removal amount distribution, and combined with the second coordinate transformation matrix, the processing parameters in the processing coordinate system are obtained; based on the processing parameters, pulsed ion beam material removal is performed on the optical element to be processed.

[0028] In this step, a pre-calibrated single-pulse removal function serves as the basis for deterministic removal. Combining the target removal amount distribution with the coordinate transformation matrix, the execution parameters adapted to the processing equipment are obtained through optimization, driving the pulsed ion beam to achieve quantitative material removal. This step uses the target removal amount as input and the second coordinate transformation matrix as the coordinate mapping basis, completing the final step from processing target to execution action. Together with the front-end measurement and data processing steps, it forms a complete processing chain, enabling high-precision deterministic material removal from complex optical surfaces, ensuring the controllability and repeatability of nanometer-level corrections, and directly improving processing accuracy and determinism.

[0029] In the aforementioned integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces, a unified workpiece coordinate system established in a single setup serves as the core benchmark. By calibrating the transformation relationship between the workpiece coordinate system and the measurement and processing coordinate systems, coordinate mismatch errors caused by repeated setup and disassembly are eliminated from both physical setup and mathematical mapping dimensions, providing a unified spatial benchmark for data alignment throughout the entire process. Under this benchmark, broadband and single-frequency interferometry channels share the measured optical path and the measured aperture to perform common aperture detection. The measurement parameters are obtained jointly using a virtual-real fusion interferometry model, avoiding benchmark deviations from discrete equipment and achieving spatial matching of multiple parameters from the same source. After coordinate mapping, the measurement parameters directly generate the target removal amount distribution, and the pulse processing parameters are solved using a calibrated single-pulse removal function, achieving seamless conversion from measurement parameters to processing commands. These core steps work together, using a unified workpiece coordinate system to connect the entire process of measurement, data processing, and processing, effectively reducing the comprehensive errors introduced by repeated setup and benchmark transformation, and improving the processing determinism and accuracy of multi-parameter collaborative correction for complex optical surfaces.

[0030] In step 201, the transferable clamping assembly refers to an integrated bearing structure used to carry the optical element to be processed, which can move between measurement, transfer and processing stations while maintaining the relative posture of the workpiece. It is a physical carrier that unifies the workpiece coordinate system.

[0031] In the specific implementation of step 201, the transferable clamping assembly includes a workpiece fixture, a transport trolley, and a repeatable positioning structure. The workpiece fixture preferably employs a kinematic positioning structure, restricting six degrees of freedom through three non-collinear reference points to ensure that the relative pose of the optical element to be processed with the fixture is uniquely determined after clamping, eliminating positioning redundancy errors from repeated clamping. The transport trolley preferably employs a guide rail-type servo-driven transfer trolley for moving along guide rails between compartments. The repeatable positioning structure preferably employs a kinematic positioning pin and positioning ball joint structure, used to cooperate with the positioning seats of the measurement and processing compartments to achieve accurate replication of the workstation position. The workpiece maintains its relative pose with the fixture throughout all subsequent measurement, transfer, and processing processes, eliminating the need for mid-process disassembly and reassembly. This fundamentally avoids positioning deviations caused by multiple clamping operations, providing a reliable physical basis for unified coordinates throughout the entire process.

[0032] In step 202, the workpiece coordinate system refers to the coordinate system established on the transferable clamping assembly and moving with the workpiece. It is a unified spatial reference throughout the entire process. The first coordinate transformation matrix is ​​the mapping relationship from the measurement coordinate system to the workpiece coordinate system, and the second coordinate transformation matrix is ​​the mapping relationship from the workpiece coordinate system to the machining coordinate system.

[0033] In the specific implementation of step 202, a workpiece coordinate system is established by setting at least one of the following on the transferable clamping assembly: a reference surface, a reference hole, a positioning ball, a coding mark, or an optical mark. The workpiece coordinate system is also the fixture coordinate system, which is transferred synchronously between the measurement and machining stations along with the transferable clamping assembly. By identifying the corresponding reference features under the measurement coordinate system and the machining coordinate system respectively, the first coordinate transformation matrix from the measurement coordinate system to the workpiece coordinate system is calculated by the coordinate transformation matrix solving and error compensation module 143. The second coordinate transformation matrix from the workpiece coordinate system to the machining coordinate system .

[0034] The mapping logic for unified coordinates can be found by referring to Figure 2 Measurement coordinate system Includes interferometric image coordinates and the positioning datum of the measuring chamber, and the workpiece coordinate system. A machining coordinate system is established based on datum planes, datum holes, and repeatable positioning features. Corresponding motion axis coordinates and machining chamber positioning datum; the measurement coordinate system and workpiece coordinate system are connected via the first coordinate transformation matrix. To achieve mapping, the workpiece coordinate system and the machining coordinate system are transformed using a second coordinate transformation matrix. To achieve the mapping, the two-level coordinate transformation matrices are cascaded to obtain the overall transformation relationship from the measurement coordinate system to the machining coordinate system. That is, any measurement point in the measurement coordinate system. Transform to the corresponding coordinates in the machining coordinate system satisfy This enables conversion and traceability across multiple coordinate systems, establishing a coordinate transformation matrix between measurement parameters and machining instructions.

[0035] If a slight offset of the reference mark is found during the retest, the local correction matrix can be re-estimated through the coordinate transformation matrix solution and error compensation module 143 to compensate for the repeated positioning error introduced by the guide rail and positioning seat, and further improve the consistency and long-term stability of the coordinate reference throughout the process.

[0036] In step 203, common aperture interferometry refers to a measurement method in which the broadband interferometry channel and the single-frequency interferometry channel share the same measured optical path segment and the measured aperture; virtual-real fusion interferometry model refers to a virtual interferometer that can simulate the actual measurement state by combining nominal optical path parameters and measured correction parameters.

[0037] In the specific implementation of step 203, the multi-parameter interferometric measurement chamber is equipped with a broadband interferometric channel and a single-frequency interferometric channel. The two channels adopt a time-division switching and same-aperture acquisition working mode. The broadband interferometric channel and the single-frequency interferometric channel complete channel selection through the optical path switching and collimation module. The two share the same measured optical path segment and measured aperture, ensuring that the spatial references of the two types of measurements are completely homogeneous, eliminating the aperture deviation and optical path deviation of discrete equipment from a physical level. The broadband interferometric channel outputs a broadband beam based on a broadband light source (supercontinuous light source) to obtain broadband reflectivity and broadband phase, and jointly invert the film thickness and optical constants. The single-frequency interferometric channel outputs a single-frequency beam based on a single-frequency light source (frequency-stabilized laser) to obtain the reflection wavefront, and obtains the surface shape and defect characteristics through system aberration calibration and phase reconstruction. The beams output from the two light sources are switched and collimated by the optical path switching and collimation module (including shutter, beam combiner, and beam expander structure) before being incident on the common-aperture interferometric module.

[0038] The common-aperture interferometry module includes a beam splitter, a test arm, a reference arm, and a reference mirror phase-shifting unit. The beam is split into a reference beam and a test beam by the beam splitter. The test beam is projected onto the surface of the optical element to be processed, and after reflection, it merges with the reference beam to form an interference signal. By sharing the test arm and reference arm of the common-aperture interferometry module, the optical path reference of the two measurements is further ensured to be consistent. The broadband interferometric signal is acquired by the spectral dispersion imaging unit to obtain broadband interferometric light intensity and broadband reflected light intensity data; the single-frequency interferometric signal is acquired by the interferogram imaging unit to obtain single-frequency interferogram data. The structure of the multi-parameter interferometric measurement chamber can be referenced. Figure 4 .

[0039] The process of obtaining measurement parameters based on the virtual-real fusion interferometry model is as follows: First, a virtual interferometer is constructed using the nominal structural parameters of the measurement optical path. These nominal structural parameters include the center wavelength and spectral width of the light source, the nominal focal length and aberrations of the collimating and imaging objectives, the reference mirror shape, the nominal curvature and aperture of the measured object, and the nominal relative pose. Second, during each measurement, the measured light source parameters, optical element parameters, relative pose parameters, and environmental parameters are collected and substituted into the virtual interferometer. The system aberrations, reference wavefront, and optical path of the virtual interferometer are calibrated and corrected in real time to obtain a virtual-real fusion interferometry model that matches the current measurement state. This method effectively reduces measurement system errors caused by system aberrations, environmental disturbances, and pose deviations, improving the accuracy of multi-parameter inversion. The environmental parameters include the actual light source spectrum, the reference mirror calibration surface shape, the ambient temperature and pressure, and the actual relative pose read by the precision displacement and environmental calibration module.

[0040] Then, the theoretical broadband reflectance consistent with the current measured conditions is calculated using a virtual-real fusion interferometry model. Theoretical broadband phase Theoretical single-frequency wavefront The measured parameters are obtained by combining the measured broadband reflectivity, broadband phase, and single-frequency wavefront with a weighted objective function optimization solution. The optimization expression for the weighted objective function is as follows: ; In the formula, This represents the optimal measurement parameter vector; The vector of parameters to be measured includes at least one of the following: film thickness, refractive index, extinction coefficient, surface shape coefficient, and defect parameter. , and These are measured broadband reflectivity, measured broadband phase, and measured single-frequency wavefront, respectively. , and These are the theoretical broadband reflectivity, theoretical broadband phase, and theoretical single-frequency wavefront calculated using the virtual-real fusion interference model, respectively. , and , where represents the weighting coefficients. The residual terms of broadband reflectance and broadband phase are summed along the measurement wavelength dimension. This multi-physical quantity joint inversion reduces the ambiguity of inversion from a single measurement, improving the consistency between the inversion of film parameters and surface parameters.

[0041] The process of optimizing and solving the measurement parameters based on the virtual-real fusion interferometric model and the weighted objective function is called multi-parameter inversion. The weighted objective function consists of the residuals and weighting coefficients between the measured broadband reflectivity, the measured broadband phase, the measured single-frequency wavefront and the corresponding theoretical values ​​of the virtual-real fusion model, and is used to describe the joint inversion problem of multiple physical quantities. Its solution algorithm can be implemented by weighted least squares, nonlinear optimization, Bayesian estimation or machine learning-assisted inversion.

[0042] It is worth noting that defect parameters are quantitative physical quantities output from the inversion, residing in the model parameter layer under the workpiece coordinate system. They describe the geometric and optical characteristics of defects, such as location, size, depth or height, shape factor, type, and scattering intensity. Defect features, on the other hand, are intermediate observations extracted from the high-frequency residuals of single-frequency phase or surface data. They reside in the signal feature layer under the detector coordinate system, exhibiting signal morphologies such as ring diffraction, local abrupt changes, and enhanced scattering. Both follow the same acquisition chain: high-frequency residuals are obtained from single-frequency phase or surface data through low-order mode fitting; defect features are identified from the high-frequency residuals; and then defect parameters are obtained through ray tracing and virtual-real fusion interferometry model inversion.

[0043] Defect feature recognition employs a combination of gradient magnitude adaptive threshold segmentation, morphological filtering, and connected component labeling. Low-order mode fitting is performed on single-frequency phase or surface data, and high-frequency residuals are extracted. Ring diffraction features, local abrupt changes, or scattering features within the high-frequency residuals are then identified. First, the local gradient magnitude is calculated for the high-frequency residuals, and candidate pixels are segmented according to a preset relative threshold, which can be 3 to 5 times the root mean square of the background noise. Then, morphological closing operations are used to remove isolated noise points, and the observed values ​​of defect features in the detector coordinate system, such as ring density, diameter, apparent depth, and scattering intensity of each connected component, are extracted. This completes the identification and classification of real defects. The position of the defect feature in the detector coordinate system is represented by the centroid of the connected component, thus obtaining the position and shape of the defect feature in the detector coordinate system.

[0044] The coordinate mapping step in the multi-parameter inversion is achieved through forward ray tracing of a virtual interferometer: the forward ray tracing establishes the mapping relationship between the detector pixel coordinates and the coordinates of the points on the measured surface. Based on this, the phase reconstruction results and defect features in the detector coordinate system are back-projected onto the measured surface. Then, combined with the first coordinate transformation matrix, they are unified to the workpiece coordinate system to obtain the surface shape parameters and defect parameters in the workpiece coordinate system. The defect parameters include at least one of the following: the three-dimensional position, size, depth or height, shape factor, type, and scattering intensity of the defect.

[0045] The aforementioned defect parameters are incorporated into the surface condition data and compared with the preset defect allowable threshold. Defects exceeding the threshold are corresponding to the generation of defect flattening and removal sub-targets.

[0046] The multi-parameter interferometric measurement chamber features a broadband light source covering approximately 400 nm to 1000 nm, and a single-frequency stable light source with wavelengths of 632.8 nm or 532 nm. The measurement chamber can maintain a wavelength of approximately 1 × 10⁻⁶ during measurement. - A vacuum or controlled atmosphere between 2 Pa and atmospheric pressure is used to reduce the impact of air disturbance and refractive index fluctuations on measurement accuracy; the precision displacement and environmental calibration module collects pose and environmental data in real time, providing input for the real-time correction of the virtual-real fusion interference model.

[0047] In step 204, surface state data refers to global spatial data that is uniformly mapped to the workpiece coordinate system and includes multi-dimensional information such as surface shape, film thickness, optical constants, and defect parameters; target removal amount distribution refers to global distribution data of the material thickness to be removed at each position in the workpiece coordinate system.

[0048] In the specific implementation of step 204, the first coordinate transformation matrix is ​​invoked to map and transform all measurement parameters obtained in step 203, such as surface shape, film thickness, optical constants, and defect parameters, to the workpiece coordinate system one by one. This ensures that each parameter corresponds to the same spatial coordinate point on the measured surface, generating global surface state data with spatial coordinate labels. This achieves precise spatial alignment of multi-dimensional parameters, providing a unified data foundation for subsequent collaborative correction. The surface shape parameters, film thickness parameters, and defect parameters are extracted from the surface state data and subjected to point-by-point difference calculations with the preset target surface shape data, target film thickness data, and defect allowable threshold. This generates corresponding sub-targets for surface shape error removal, film thickness homogenization removal, and defect flattening removal.

[0049] Based on preset processing priority rules, material removal boundary conditions, and processing safety margin parameters, spatial coordinate matching and superposition calculations are performed on each removal sub-target to synthesize the target removal amount distribution in the entire workpiece coordinate system, thereby achieving collaborative correction of multi-dimensional errors and avoiding component damage caused by over-processing.

[0050] For example, the processing priority rule can be set as follows: surface shape error correction takes precedence over film thickness homogenization, and film thickness homogenization takes precedence over defect planarization; when the defect depth or height exceeds the component damage threshold, defect planarization is upgraded to the highest priority. The material removal boundary is based on the nominal contour of the component under test, and each removal sub-target must not cross the film layer or substrate interface. The film layer correction area reserves a boundary margin from the component edge inward, for example, 1 mm to 5 mm; the defect correction area extends outward by at least one beam radius. The processing safety margin parameter can be taken as 0.5 nm to 2 nm, or as 10% to 30% of the peak value of the target removal amount, to retain the closed-loop iteration margin and avoid overcutting.

[0051] For complex optical surfaces containing different spatial frequency errors, the target removal amount distribution is decomposed into spatial frequency bands to obtain at least two sets of removal quantum numbers in different spatial frequency bands. For each set of removal quantum numbers in a frequency band, the corresponding beam diameter, scanning spacing or processing round parameters are matched to form hierarchical target removal amount data for frequency division processing.

[0052] Specifically, when decomposing the target removal amount distribution into spatial frequency bands, it can be decomposed into three sets of removal quantum errors: low-frequency error, mid-frequency error, and local high-frequency error. Low-frequency error is handled using processing parameters with a larger beam diameter and larger scanning spacing; mid-frequency error is handled using processing parameters with a smaller beam diameter and denser scanning paths; and local high-frequency error is addressed when the equipment's dynamic performance and removal function bandwidth allow, balancing large-scale surface convergence efficiency with the accuracy of local defect correction, thereby improving overall processing efficiency.

[0053] For example, the target removal amount can be decomposed into low-frequency errors (f≤0.05mm) according to the spatial frequency f.- ¹, Spatial wavelength ≥ 20 mm, intermediate frequency error (0.05 mm) - ¹<f≤1mm - ¹) and local high-frequency error (f > 1mm) - ¹, Spatial wavelength < 1 mm). For low-frequency errors, the beam spot diameter should be 1 / 3 to 1 / 2 of the spatial wavelength, and the scanning spacing should be 1 / 3 to 1 / 2 of the beam spot diameter; for mid-frequency errors, the beam spot diameter should be 1 / 4 to 1 / 3 of the spatial wavelength, and the scanning spacing should be 1 / 4 to 1 / 3 of the beam spot diameter; for local high-frequency errors, when the beam spot diameter and dynamic performance allow, the beam spot diameter should not exceed 1 / 3 of the spatial wavelength, and the scanning spacing should not exceed 1 / 2 of the beam spot diameter. Otherwise, the high-frequency components will be included in the local defect flattening process.

[0054] After the above frequency band decomposition and parameter matching, each set of removed quantum particles carries the corresponding beam diameter, scanning spacing and processing round label, and is organized into hierarchical target removal amount data in order of spatial frequency from low to high, which serves as the input basis for subsequent processing in different rounds.

[0055] Based on the aforementioned graded target removal data, frequency division processing is performed sequentially in stages according to spatial frequencies from low to high. The first stage uses a large beam spot diameter and a large scanning interval to complete the low-frequency error correction across the entire domain, quickly converging large-scale contour deviations. The second stage uses a medium beam spot and a moderate scanning interval to complete the mid-frequency error convergence, improving the surface quality of the mid-frequency band. The final stage uses a small beam spot to complete the flattening correction of local high-frequency errors and discrete defects. Each stage of processing can be started and stopped independently, and after processing, it can be returned to the measurement station for retesting and verification to ensure that the errors in each frequency band converge gradually and controllably.

[0056] Furthermore, for planar optical elements with single or multiple dielectric films, film thickness correction sub-targets and defect flattening sub-targets can be established separately. First, a larger beam spot diameter is used to correct low-frequency film thickness errors, and then a smaller beam spot diameter and fewer pulses are used to correct local defects. For aspherical or freeform optical elements, a corresponding virtual model can be established based on the nominal surface. The actual surface parameters and surface shape errors can be obtained through nonlinear optimization, and then frequency division processing can be carried out.

[0057] In step 205, the single-pulse removal function refers to the function that describes the removal morphology distribution produced after a single pulsed ion beam acts on the material surface, and it is the core foundation of pulsed ion beam deterministic processing.

[0058] In the specific implementation of step 205, the single-pulse removal function is based on the incident ion energy deposition distribution, sputtering yield, beam density, incident angle and material surface binding energy to construct a theoretical model. The theoretical model is calibrated through single-pulse or few-pulse removal experiments on standard samples to obtain the calibrated single-pulse removal function. The pulse duty cycle is adjusted by changing the ion fluence during the conduction period of a single pulse to regulate the amplitude output of the single-pulse removal function, thereby achieving discrete and fine control of the removal amount and adapting to the correction requirements of nanometer-level precision.

[0059] For example, the single-pulse removal function can be expressed in Gaussian form: ; In the formula, This is the radial distance from the center of the beam spot; Remove depth from the center of the single pulse; The characteristic width of the removal function is determined by the beam focusing and energy deposition distribution of the ion optics system.

[0060] Single pulse center removal depth With sputtering output Beam density Pulse conduction time and material atomic number density satisfy: ; ; In the formula, Duty cycle, This refers to the pulse frequency and duty cycle. Down Approximately monotonically increasing, established after calibration Relationship curve; repetition at the same position During each pulse, the cumulative removal amount is calculated as follows: Linear superposition.

[0061] By combining the second coordinate transformation matrix, the target removal amount distribution in the workpiece coordinate system is mapped and transformed to the machining coordinate system. The cumulative removal amount is obtained by superimposing calibrated single-pulse removal functions. The machining parameters are then optimized to approximate the target removal amount distribution using the cumulative removal amount as the objective, resulting in a deterministic machining strategy. The expression for calculating the cumulative removal amount is: ; In the formula, For machining coordinates Cumulative removal amount at the location; For the first The number of pulses at each processing position; For the first The calibration single-pulse removal function corresponding to each processing position; For beam energy, The pulse duty cycle. The incident angle of the ion beam. For the first The coordinates of each machining position in the machining coordinate system.

[0062] In solving the processing parameters, non-negative integer constraints are applied to the pulse number; equipment constraints are applied to the motion axis speed, acceleration, pulse frequency, duty cycle, and maximum single-pass removal amount of the workpiece scanning and positioning module; the pulse number, pulse frequency, dwell time, and scanning speed satisfy a coupling relationship determined by the beam spot scanning spacing and single-point dwell time; where the beam spot scanning spacing is the distance between adjacent processing positions, and is the same physical quantity as the scanning spacing matching the quantum set removal of each frequency band in frequency division processing; single-point dwell time is the dwell time of the pulsed ion beam at a single processing position; independent variables are selected as decision variables and the remaining parameters are derived quantities during the solution process to avoid over-constraint and multiple solutions, ensuring the executability and physical rationality of the processing parameters, and avoiding motion over-limits or parameter conflicts during processing. The obtained processing parameters include at least one or more of the following: pulse number, pulse frequency, pulse duty cycle, beam energy, scanning trajectory, scanning speed, and dwell time.

[0063] Optimization solutions can be obtained using sequential quadratic programming, interior-point methods, particle swarm optimization, or genetic algorithms. The pulse number is treated as an integer variable, while other continuous variables are treated as equipment constraints. During the solution process, pulse number, pulse frequency, beam energy, and duty cycle are preferentially selected as decision variables, while dwell time and scan speed are used as derived variables to avoid over-constraints and multiple solutions.

[0064] Before processing, the relative positions of the optical element to be processed and the transferable clamping assembly are kept constant. The transfer from the measurement station to the processing station is completed via a buffer chamber, maintaining the workpiece's position. Specifically, the buffer chamber first undergoes pressure and temperature matching with the multi-parameter interferometric measurement chamber. Once the pressure and temperature differences between the two chambers meet the preset interlocking thresholds, and the transferable clamping assembly is in a locked-ready state, the first isolation valve is opened, moving the workpiece-bearing transferable clamping assembly into the buffer chamber. Subsequently, the two isolation valves remain closed, and the pressure and temperature within the buffer chamber are independently adjusted to match the pulsed ion beam processing chamber. After re-verifying the pressure and temperature matching conditions and the workpiece's locking state, the second isolation valve is opened, transporting the transferable clamping assembly to the processing station and locking it in position. Throughout the transfer process, the workpiece's clamping state remains unchanged and is always within a controlled environmental range. The workpiece's temperature during measurement, transfer, and processing can be controlled within ±0.1℃ of the set value, avoiding temperature fluctuations, stress changes, and surface adsorption state drift caused by exposure to the atmosphere, ensuring consistency between the measurement and processing states.

[0065] During processing, the pulse power supply and trigger module outputs pulse signals according to the processing parameters, driving the pulse ion source to generate a pulsed ion beam. After being focused, collimated, or having its beam diameter adjusted by the ion optics and beam current monitoring module 133, the ion beam is projected onto the surface of the optical element to be processed. The workpiece scanning and positioning module adjusts the spatial position of the workpiece and the ion beam incident angle according to the processing trajectory. Non-contact material removal is achieved through cascade collisions between ions and atoms on the material surface, eliminating mechanical contact stress and making it suitable for high-precision processing of hard and brittle optical materials. For insulated optical elements, electron neutralization or low-energy charge compensation units can be added to reduce the surface charging effect. The structure of the pulsed ion beam processing chamber can be referenced. Figure 6 .

[0066] In practice, the pulsed ion beam can use argon ions, with a beam energy of approximately 300 eV to 2 keV, a pulse frequency of approximately 1 Hz to 10 kHz, a duty cycle of approximately 1% to 90%, and a beam diameter of approximately 1 mm to 20 mm; the processing chamber is maintained at approximately 1 × 10⁻⁶ during processing. - ³Pa to 1×10 - A high vacuum environment of 2Pa is maintained. The beam monitoring module collects real-time data on beam density, pulse waveform, and beam spot position for real-time correction during processing, promptly detecting beam drift and waveform anomalies, thus improving the stability of the processing. For curved optical elements, the ion beam incident angle varies at different locations. The amplitude and shape of the single-pulse removal function need to be corrected based on the local normal vector. Combined with multi-axis linkage, a processing trajectory adapted to the curved surface is generated to ensure the accuracy of the removal amount calculation at each location on the curved surface, thereby improving the processing precision of complex curved surfaces.

[0067] After the pulsed ion beam material removal is completed, a re-measurement feedback and closed-loop iterative processing are performed, including: maintaining the relative pose of the optical element to be processed and the transferable clamping assembly constant; based on the first coordinate transformation matrix, returning the processed optical element to be processed to the measurement station via a buffer chamber; completing the re-measurement acquisition under the same measurement coordinate system reference; and transmitting the acquired re-measurement measurement parameters to the control system. Based on the re-measurement measurement parameters and the surface state data before processing, the control system obtains the actual removal amount distribution and processing residual, and corrects the characteristic parameters of the single-pulse removal function online according to the deviation between the actual removal amount and the theoretically predicted removal amount. The correction parameters include at least one of the following: removal depth proportionality coefficient, beam spot center offset, beam spot width, incident angle influence coefficient, and material removal efficiency. Real-time compensation is provided for beam drift, material differences, and dynamic errors of the motion system to improve the determinism of subsequent processing rounds.

[0068] The processing residual is compared with a preset termination threshold. If the preset termination threshold is not met, the target removal amount distribution and processing parameters are updated based on the processing residual, and steps 203 to 205 are repeated. If the preset termination threshold is met, the processing ends. The preset termination threshold includes at least one of the following: surface shape error threshold, film thickness error threshold, defect height or depth threshold, and upper limit of iteration count.

[0069] To avoid the impact of thermal differences caused by processing heat on the retest judgment, the retest is performed after the workpiece temperature has stabilized within the set measurement temperature range, or temperature-thermal deformation compensation is applied to the retest data to eliminate the interference of processing thermal deformation on the retest accuracy and ensure the accuracy of residual judgment. Online updates of the single-pulse removal function can be achieved using recursive least squares, Kalman filtering, or proportional correction methods. Online updates only apply to subsequent processing cycles and do not change completed processing data, ensuring the traceability of the process.

[0070] In addition, before formal processing, single-pulse, few-pulse, and different duty cycle processing experiments can be carried out on standard samples with the same or similar materials and film systems as the workpiece to be processed. The surface difference before and after processing can be measured using a multi-parameter interferometric measurement system to obtain the single-pulse removal depth, beam width, beam center, and repeatability. The calibration relationship between the removal function parameters and beam energy, frequency, duty cycle, incident angle, and material type can be established, providing an accurate basic model for solving the processing parameters and ensuring the accuracy of deterministic processing.

[0071] It should be understood that, although this embodiment Figure 1 The steps are shown sequentially as indicated by the arrows, but they are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order in which these steps are performed; they can be executed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0072] Example 2 Based on the integrated method of multi-parameter interferometry and pulsed ion beam measurement and processing for complex surfaces in Example 1, this embodiment discloses an integrated device for multi-parameter interferometry and pulsed ion beam measurement and processing for complex surfaces, such as... Figures 3 to 6 As shown, the integrated device for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces includes: a multi-parameter interferometry chamber 110, a buffer chamber 120, a pulsed ion beam processing chamber 130, a transferable clamping assembly 150, and a control and data processing system 140.

[0073] The buffer chamber 120 is located between the multi-parameter interferometric measurement chamber 110 and the pulsed ion beam processing chamber 130. The two sides of the buffer chamber 120 are selectively connected to the multi-parameter interferometric measurement chamber 110 and the pulsed ion beam processing chamber 130 through isolation valves, respectively, so as to realize the state-maintaining transfer of the workpiece between the measurement station and the processing station while maintaining the clamping state.

[0074] The transferable clamping assembly 150 is used to carry the optical element to be processed. It can move along the transfer guide rail between the multi-parameter interferometry chamber 110, the buffer chamber 120, and the pulsed ion beam processing chamber 130. Based on a unified workpiece coordinate system, the measurement parameters and processing commands can be mapped across workstations through a coordinate transformation matrix. The relative position of the optical element to be processed and the transferable clamping assembly 150 remains fixed throughout the measurement, transfer, and processing processes.

[0075] The control and data processing system 140 is communicatively connected to the multi-parameter interferometric measurement chamber 110, the buffer chamber 120, the pulsed ion beam processing chamber 130, and the transferable clamping assembly 150, and is used to perform measurement parameter inversion, coordinate mapping, target removal amount calculation, processing parameter solving, transfer interlock control, and processing closed-loop feedback control.

[0076] Specifically, each compartment and functional unit is arranged sequentially along the transfer axis. Through the coordinated cooperation of mechanical interface, optical interface, gas interface and communication interface, they jointly realize multi-parameter measurement, state-maintaining transfer, pulsed ion beam processing and closed-loop iterative correction in a single clamping. Its core working principle corresponds one-to-one with the method described in Example 1.

[0077] The multi-parameter interferometric measurement chamber 110 is an integrated carrier for measurement functions. Internally, it integrates a broadband light source 111, a single-frequency light source 112, an optical path switching and collimation module 114, a common aperture interferometry module 115, a spectral dispersion imaging module 116, an interferogram imaging module 117, and a precision displacement and environmental calibration module 118. The overall structure can be referenced from [reference needed]. Figure 4 .

[0078] The output ends of the broadband light source 111 (supercontinuous light source) and the single-frequency light source 112 (frequency-stabilized laser) are both optically connected to the input end of the optical path switching and collimation module 114. The optical path switching and collimation module 114 has built-in shutter, beam combining and beam expanding units, and its output optical path is connected to the incident end of the common aperture interference module 115. It is used to switch between the broadband measurement channel and the single-frequency measurement channel and output a collimated beam, so that the two types of measurements share the same measured optical path segment and measured aperture, and ensure that the spatial reference is of the same source from the physical structure.

[0079] The common aperture interferometer module 115 integrates a beam splitter, a test arm, a reference arm, and a phase-shifting unit for the reference mirror. The optical path of the test arm is projected onto the surface of the optical element to be processed, and the optical path of the reference arm is projected onto the reference mirror. The broadband signal output terminal of the module is connected to the spectral dispersion imaging module 116 to output broadband interference light intensity and broadband reflected light intensity signals. The single-frequency signal output terminal of the module is connected to the interferogram imaging module 117 to output single-frequency interferogram signals. The data output terminals of both the spectral dispersion imaging module 116 and the interferogram imaging module 117 are electrically connected to the control and data processing system 140 to upload the acquired raw optical signal data for multi-parameter inversion. The inversion calculation process is consistent with the solution logic of the virtual-real fusion interferometric model and weighted objective function in step 203 of Example 1.

[0080] The acquisition terminals of the precision displacement and environmental calibration module 118 are respectively arranged at key optical path nodes and around the workpiece clamping position in the common aperture interferometry module 115. The data output terminals are electrically connected to the control and data processing system 140 to acquire pose, temperature, and air pressure data in real time and output real-time correction values. This provides real-time calibration input for the virtual-real fusion interferometry model, reducing the impact of system aberrations and environmental disturbances on measurement accuracy. The measurement chamber is equipped with independent vacuum and temperature control interfaces to maintain a controlled environment during the measurement process, further improving measurement stability.

[0081] The broadband interferometer channel, consisting of a broadband light source 111, an optical path switching and collimation module 114, a common aperture interferometer module 115, and a spectral dispersion imaging module 116, is used for film thickness and optical constant measurement. The single-frequency interferometer channel, consisting of a single-frequency light source 112, an optical path switching and collimation module 114, a common aperture interferometer module 115, and an interferogram imaging module 117, is used for surface shape and defect measurement. The two channels are time-division selected by the optical path switching and collimation module 114 and share the same measured optical path segment and measured aperture to achieve common aperture acquisition of the broadband channel and the single-frequency channel.

[0082] The buffer chamber 120 is the core unit for maintaining the transfer status. It integrates a first isolation valve 121, a second isolation valve 122, an independent inflation / deflation unit 123, a temperature control unit 124, and a transfer, conveying, and locking unit 125. The overall structure can be referenced. Figure 5 .

[0083] The first isolation valve 121 is installed on the docking side of the buffer chamber 120 and the multi-parameter interferometry chamber 110, and the second isolation valve 122 is installed on the docking side of the buffer chamber 120 and the pulsed ion beam processing chamber 130. The drive control terminals of both isolation valves are electrically connected to the control and data processing system 140, which performs interlock opening and closing control. The necessary conditions for interlock opening are pressure matching, temperature matching, and normal workpiece clamping and locking status of the two chambers. The interlock can only be opened after the pressure of the two chambers is matched to avoid pressure difference shock and sudden environmental changes.

[0084] The independent inflation / extraction unit 123 and temperature control unit 124 are both connected to the buffer chamber 120, and their control ends are electrically connected to the control and data processing system 140. These units are used to independently adjust the pressure and temperature within the buffer chamber 120 when both isolation valves are closed, achieving environmental matching with the target chamber. The transfer and locking unit 125 runs along the transfer axis through the buffer chamber 120, with both ends precisely docking with the transfer rails in the multi-parameter interferometry chamber 110 and the pulsed ion beam processing chamber 130, respectively. This allows the transferable clamping assembly 150 to reciprocate between the three chambers. The locking structure control end of the transfer and locking unit 125 is electrically connected to the control and data processing system 140, used for positioning and locking the transferable clamping assembly 150 after it reaches its designated position, ensuring accurate repetitive positioning and compensating for minor deviations caused by the rail docking.

[0085] The complete transfer process of the buffer chamber 120 is consistent with the state-preserving transfer logic in step 205 of Example 1, maintaining the workpiece clamping state unchanged throughout the process and avoiding workpiece state drift caused by atmospheric exposure.

[0086] The pulsed ion beam processing chamber 130 serves as the execution carrier for material removal. Internally, it integrates a pulsed ion source 131, a pulsed power supply and triggering module 132, an ion optics and beam current monitoring module 133, a workpiece scanning and positioning module 134, a processing controller 135, a vacuum process unit 136, and a charge neutralization unit. The overall structure can be referenced from [reference needed]. Figure 6 .

[0087] The control terminal of the pulse power supply and trigger module 132 is electrically connected to the control and data processing system 140, and the power output terminal is electrically connected to the pulse ion source 131. It is used to receive processing parameter instructions, independently adjust the frequency, duty cycle and pulse number of the pulse ion beam, and realize discrete and fine control of the amount of material removed.

[0088] The gas inlet of the pulsed ion source 131 is connected to the gas supply pipeline of the vacuum process unit 136. The pulsed high-voltage input terminal is electrically connected to the power output terminal of the pulse power supply and the trigger module 132. The beam control terminal is connected to the beam parameter output of the processing controller 135. The source body integrates an ionization region, an extraction grid and a beam shaping structure in sequence. It can complete the ionization of process gas, ion beam extraction and preliminary beam shaping under pulsed high-voltage triggering, and output a pulsed ion beam with adjustable parameters. Its beam output terminal is connected to the incident terminal of the ion optics and beam monitoring module 133.

[0089] The ion optics and beam monitoring module 133 has a built-in focusing / collimation structure and beam density monitoring structure. The output end corresponds to the workpiece clamping position of the workpiece scanning and positioning module 134. Its beam monitoring signal output end is electrically connected to the control and data processing system 140 for real-time feedback of beam status.

[0090] The multi-axis motion control terminal of the workpiece scanning and positioning module 134 is electrically connected to the motion control output terminal of the processing controller 135, covering three core functions: multi-axis motion, incident angle adjustment, and single-clamping positioning. It is used to carry the transferable clamping assembly 150 and adjust the spatial position and ion beam incident angle of the workpiece, adapting to the processing trajectory requirements of various complex optical surfaces such as planes, spheres, and aspherical surfaces.

[0091] The communication terminal of the processing controller 135 is electrically connected to the control and data processing system 140 to receive the parsed pulse parameters, scanning trajectory and dwell time commands; its beam parameter output terminal is electrically connected to the pulse ion source 131 to send operating parameters such as beam energy and gate voltage to the ion source; its motion control output terminal is electrically connected to the workpiece scanning and positioning module 134 to send multi-axis motion trajectory and point dwell commands to realize synchronous matching control of beam parameters and workpiece scanning motion.

[0092] The gas path of the vacuum process unit 136 is connected to the gas inlet of the processing chamber and the pulse ion source 131, respectively. The control end is electrically connected to the control and data processing system 140. The unit integrates a process gas supply branch, a vacuum pumping branch and a pressure monitoring unit, covering three core functions: gas supply, pumping and pressure monitoring. It is used to supply a stable working process gas to the pulse ion source, and at the same time to pump and maintain a high vacuum working environment for the processing chamber. The vacuum degree and gas supply flow are closed-loop regulated through real-time pressure monitoring data.

[0093] The charge neutralization unit is arranged near the workpiece clamping position, and its control terminal is electrically connected to the machining controller 135. It is used to start synchronously during the machining of insulating optical elements, output low-energy electrons to compensate for the accumulation of charge on the workpiece surface, and reduce the surface charging effect during the machining of insulating optical elements.

[0094] The material removal mechanism and processing parameter solution logic of the pulsed ion beam are consistent with those described in step 205 of Example 1, and deterministic material removal is achieved based on the calibrated single-pulse removal function.

[0095] The transferable clamping assembly 150 includes a workpiece clamp, a transport trolley, and a repeatable positioning structure. It is a physical carrier for a unified workpiece coordinate system, and its structure and positioning principle are consistent with those described in steps 201 and 202 of Embodiment 1.

[0096] The workpiece fixture is used to fix the optical components to be processed. After clamping, the relative posture of the two remains unchanged throughout the process. The transport trolley cooperates with the transfer and locking unit 125 and moves along the guide rail between the three compartments. The repeatable positioning structure cooperates with the positioning seats in the measuring compartment and the processing compartment respectively to realize the accurate reproduction of the work position and keep the workpiece coordinate system stable after multiple round trips. Its small deviation can be corrected by the coordinate transformation matrix.

[0097] The control and data processing system 140 is the central unit of the device, with built-in data acquisition module, multi-parameter inversion module, coordinate unification module, target removal amount generation module, pulse processing planning module, equipment interlocking module and closed-loop judgment module. The data of each module is interconnected and operates in coordination.

[0098] The data acquisition module is connected to various sensors and acquisition units in the measurement chamber, buffer chamber, and processing chamber, and is responsible for the acquisition and preprocessing of raw measurement parameters, environmental parameters, and beam state data. The multi-parameter inversion module, coordinate unification module, target removal amount generation module, and pulse processing planning module are connected in sequence to complete the full-link calculation from raw measurement parameters to processing parameters. Its algorithm logic corresponds to steps 202 to 205 in Example 1.

[0099] The equipment interlocking module communicates with the isolation valve, gas filling unit, transport trolley, ion source, and other actuators to control chamber opening and closing, pressure balancing, transfer sequence, and processing safety interlocks, ensuring the safety and timing accuracy of equipment operation. The closed-loop determination module receives retest data, calculates processing residuals, determines iteration termination conditions, triggers the next round of processing, or outputs the final result, achieving closed-loop automatic control of the entire process.

[0100] In this embodiment, the specific working principles, parameter values, and process logic of each unit of the device correspond one-to-one with the method steps in Embodiment 1, and will not be repeated here. Each functional module can be implemented entirely or partially through software, hardware, or a combination thereof. Each module can be embedded in the processor of the device in hardware form or independent of it, or it can be stored in the memory in software form so that the processor can call and execute the corresponding operation.

[0101] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0102] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A method for integrating multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces, characterized in that, The method includes: Step 201: Fix the optical element to be processed to the transferable clamping assembly. The relative position of the optical element to be processed and the transferable clamping assembly remains unchanged throughout the measurement, transfer and processing process. Step 202: Establish a workpiece coordinate system on the transferable clamping assembly, calibrate the first coordinate transformation matrix between the workpiece coordinate system and the measurement coordinate system, and calibrate the second coordinate transformation matrix between the workpiece coordinate system and the machining coordinate system; Step 203: By sharing the broadband interference channel and the single-frequency interference channel of the optical path segment and the aperture under test, perform common aperture interferometry on the optical element to be processed, collect broadband interference signals and single-frequency interference signals respectively, and then obtain measurement parameters based on the virtual-real fusion interference model; Step 204: Based on the first coordinate transformation matrix, the measurement parameters are uniformly mapped to the workpiece coordinate system to generate surface state data with spatial coordinate correspondence; the surface state data is compared with the target surface data to obtain the target removal amount distribution in the workpiece coordinate system. Step 205: Based on the pre-calibrated single-pulse removal function and the target removal amount distribution, and combined with the second coordinate transformation matrix, the processing parameters in the processing coordinate system are obtained; based on the processing parameters, pulsed ion beam material removal is performed on the optical element to be processed.

2. The integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 1, characterized in that, Measurement parameters are obtained based on a virtual-real fusion interferometry model, including: A virtual interferometer is constructed by measuring the nominal parameters of the optical path, and the virtual interferometer is corrected in real time by measuring the light source parameters, optical element parameters, relative pose parameters and environmental parameters to obtain a virtual-real fusion interference model; The theoretical broadband reflectivity, theoretical broadband phase, and theoretical single-frequency wavefront are obtained by using a virtual-real fusion interferometry model. Then, the measurement parameters are obtained by optimizing the solution based on a weighted objective function.

3. The integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 2, characterized in that, The optimized solution expression for the weighted objective function is as follows: ； In the formula, This represents the optimal measurement parameter vector; The vector of parameters to be measured includes at least one of the following: film thickness, refractive index, extinction coefficient, surface shape coefficient, and defect parameter. , and These are measured broadband reflectivity, measured broadband phase, and measured single-frequency wavefront, respectively. , and These are the theoretical broadband reflectivity, theoretical broadband phase, and theoretical single-frequency wavefront calculated using the virtual-real fusion interference model, respectively. , and These are the weighting coefficients.

4. The integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 1, characterized in that, The surface condition data is compared with the target surface data to obtain the target removal amount distribution in the workpiece coordinate system, including: The surface shape parameters, film thickness parameters and defect parameters in the surface state data are extracted respectively, and point-by-point difference calculations are performed with the preset target surface shape data, target film thickness data and defect allowable threshold to generate corresponding surface shape error removal sub-targets, film thickness uniformity removal sub-targets and defect flattening removal sub-targets. Based on the preset processing priority rules, material removal boundary conditions and processing safety margin parameters, spatial coordinate matching and superposition operations are performed on the surface shape error removal sub-target, the film thickness uniformity removal sub-target and the defect flattening removal sub-target to synthesize the target removal amount distribution in the whole domain under the workpiece coordinate system. For complex optical surfaces containing different spatial frequency errors, the target removal amount distribution is decomposed into spatial frequency bands to obtain at least two sets of removal quantum numbers in different spatial frequency bands. For each set of removal quantum numbers in a frequency band, the corresponding beam diameter, scanning spacing or processing round parameters are matched to form hierarchical target removal amount data for frequency division processing.

5. The integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 4, characterized in that, The spatial frequency band decomposition of the target removal amount distribution includes: The target removal amount distribution is decomposed into three removal quantum sets: low-frequency error, mid-frequency error, and local high-frequency error. Among them, the low-frequency error is processed with a larger beam diameter and a larger scanning spacing, the mid-frequency error is processed with a smaller beam diameter and a denser scanning path, and the local high-frequency error is processed when the dynamic performance of the equipment and the bandwidth of the removal function allow it.

6. The integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 1, characterized in that, Based on the pre-calibrated single-pulse removal function and the target removal amount distribution, and combined with the second coordinate transformation matrix, the machining parameters in the machining coordinate system are obtained, including: A theoretical model of the single-pulse removal function was constructed based on incident ion energy deposition distribution, sputtering yield, beam density, incident angle, and material surface binding energy. The theoretical model was calibrated through single-pulse or few-pulse removal experiments on standard samples to obtain the calibrated single-pulse removal function. Combining the second coordinate transformation matrix, the target removal amount distribution in the workpiece coordinate system is mapped and transformed to the machining coordinate system; then, the cumulative removal amount is obtained by superimposing the calibrated single-pulse removal function, and the machining parameters are optimized to approximate the target removal amount distribution with the cumulative removal amount as the objective; the machining parameters include one or more of the following: pulse number, pulse frequency, pulse duty cycle, beam energy, scanning trajectory, scanning speed, and dwell time.

7. The integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 6, characterized in that, The formula for calculating the cumulative removal amount is: ； In the formula, For machining coordinates The cumulative amount removed at the location; For the first The number of pulses at each processing position; For the first The calibration single-pulse removal function corresponding to each processing position; For beam energy, The pulse duty cycle. The incident angle of the ion beam. For the first The coordinates of each machining position in the machining coordinate system.

8. The integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 6, characterized in that, In the process of solving the machining parameters, non-negative integer constraints are applied to the number of pulses; equipment constraints are applied to the motion axis speed, acceleration, pulse frequency, duty cycle, and maximum removal amount per cycle. The pulse number, pulse frequency, dwell time and scanning speed satisfy a coupling relationship determined by the beam spot scanning spacing and single-point dwell time. When solving, independent variables are selected as decision variables and the remaining parameters are derived variables.

9. The integrated method for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to any one of claims 1 to 8, characterized in that, After pulsed ion beam material removal is completed, a retest feedback and closed-loop iterative processing are performed, including: Keeping the relative pose of the optical element to be processed and the transferable clamping assembly constant, based on the first coordinate transformation matrix, the processed optical element to be processed is returned to the measurement coordinate system for re-measurement with the same reference to obtain the actual removal amount and processing residual. Based on the deviation between the actual removal amount and the theoretically predicted removal amount, the characteristic parameters of the single-pulse removal function are corrected online. At the same time, the processing residual is compared with the preset termination threshold. If the preset termination threshold is not met, the target removal amount distribution and processing parameters are updated according to the processing residual, and steps 203 to 205 are repeated. When the preset termination threshold is met, the processing ends.

10. An integrated device for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces, characterized in that, The device includes: a multi-parameter interferometric measurement chamber, a buffer chamber, a pulsed ion beam processing chamber, a transferable clamping assembly, and a control and data processing system; The buffer chamber is located between the multi-parameter interferometric measurement chamber and the pulsed ion beam processing chamber, and its two sides are selectively connected to the multi-parameter interferometric measurement chamber and the pulsed ion beam processing chamber through isolation valves, respectively, so as to realize the state-maintaining transfer of the workpiece between the measurement station and the processing station while maintaining the clamping state. The transferable clamping assembly is used to carry the optical element to be processed and can move between the multi-parameter interferometry chamber, the buffer chamber and the pulsed ion beam processing chamber. The relative position of the optical element to be processed and the transferable clamping assembly remains fixed throughout the measurement, transfer and processing process. The control and data processing system is communicatively connected to the multi-parameter interferometric measurement chamber, the buffer chamber, the pulsed ion beam processing chamber, and the transferable clamping assembly, and is used to perform measurement parameter inversion, coordinate mapping, target removal amount calculation, processing parameter solving, transfer interlock control, and processing closed-loop feedback control.

11. The integrated device for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 10, characterized in that, The multi-parameter interferometric measurement chamber includes a broadband light source, a single-frequency light source, an optical path switching and collimation module, a common aperture interferometry module, a spectral dispersion imaging module, an interferogram imaging module, and a precision displacement and environmental calibration module. The output ends of both the broadband light source and the single-frequency light source are optically connected to the input end of the optical path switching and collimation module; the output end of the optical path switching and collimation module is optically connected to the incident end of the common aperture interference module, which is used to switch the measurement channel and output a collimated beam, so that the broadband measurement and the single-frequency measurement share the same measured optical path segment and the measured aperture. The broadband signal output of the common aperture interferometer module is connected to the spectral dispersion imaging module, and the single-frequency signal output is connected to the interferogram imaging module. The data outputs of both the spectral dispersion imaging module and the interferogram imaging module are electrically connected to the control and data processing system to transmit the acquired interferometric signals to the control and data processing system for multi-parameter inversion. The acquisition terminals of the precision displacement and environmental calibration module are respectively arranged around the common aperture interference module and the workpiece clamping position. The data output terminal is electrically connected to the control and data processing system to acquire pose and environmental parameters and output correction values, providing a calibration basis for the virtual-real fusion interference model.

12. The integrated device for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 10, characterized in that, The buffer chamber includes a first isolation valve, a second isolation valve, an independent inflation / deflation unit, a temperature control unit, and a transfer and locking unit; The first isolation valve is located on the docking side between the buffer chamber and the multi-parameter interferometry chamber, and the second isolation valve is located on the docking side between the buffer chamber and the pulsed ion beam processing chamber; the drive control terminals of the first isolation valve and the second isolation valve are electrically connected to the control and data processing system, and the control system performs interlocking opening and closing control. The independent inflation / deflation unit and the temperature control unit are both connected to the buffer chamber cavity, and their control terminals are electrically connected to the control and data processing system. They are used to independently adjust the pressure and temperature inside the buffer chamber to achieve environmental matching between the two chambers. The transfer and locking unit passes through the cavity of the buffer chamber along the transfer axis, and its two ends are respectively connected to the transfer guide rails in the multi-parameter interferometry chamber and the pulsed ion beam processing chamber. It is used to carry the reciprocating movement of the transferable clamping assembly and to perform positioning and locking on the transferable clamping assembly after it is in place.

13. The integrated device for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 10, characterized in that, The pulsed ion beam processing chamber includes a pulsed ion source, a pulsed power supply and triggering module, an ion optics and beam monitoring module, a workpiece scanning and positioning module, a processing controller, and a vacuum process unit. The control terminal of the pulse power supply and trigger module is electrically connected to the control and data processing system, and the power output terminal is electrically connected to the pulse ion source, which is used to independently adjust the frequency, duty cycle and pulse number of the pulse ion beam. The beam output end of the pulsed ion source is connected to the incident end of the ion optics and beam monitoring module. The output end of the ion optics and beam monitoring module corresponds to the workpiece clamping position of the workpiece scanning and positioning module, and the beam monitoring signal output end is electrically connected to the control and data processing system. The multi-axis motion control terminal of the workpiece scanning and positioning module is electrically connected to the processing controller and is used to adjust the spatial position of the workpiece and the ion beam incident angle. The communication terminal of the processing controller is electrically connected to the control and data processing system, the beam parameter output terminal is electrically connected to the pulse ion source, and the motion control output terminal is electrically connected to the workpiece scanning and positioning module. It is used to receive and parse pulse parameters, scanning trajectory and dwell time instructions, and synchronously realize the matching control of beam parameter issuance and workpiece scanning motion. The gas path of the vacuum process unit is connected to the gas inlet of the processing chamber and the pulse ion source, and the control end is electrically connected to the control and data processing system to provide process gas and vacuum working environment.

14. The integrated device for multi-parameter interferometry and pulsed ion beam measurement and processing of complex surfaces according to claim 13, characterized in that, The pulsed ion beam processing chamber also includes a charge neutralization unit; The charge neutralization unit is arranged near the workpiece clamping position, and its control terminal is electrically connected to the processing controller. It is used to output low-energy electrons to compensate for the charge accumulation on the workpiece surface during the processing of insulating optical elements.

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