Device and method for optimizing non-uniformity of light intensity distribution of ZnSe lens

Abstract

The application discloses a device and method for optimizing non-uniformity of light intensity distribution of a ZnSe lens, which comprises a first light source module for simulating low absorption rate of CO2 laser of a to-be-irradiated ZnSe lens, a second light source module for simulating thermal load of the to-be-irradiated ZnSe lens, a beam combination module for obtaining sampling light of mixed wavelengths through beam combination, a detection module for detecting wavefront distortion and output power of the sampling light and temperature of the to-be-irradiated ZnSe lens after irradiation of the sampling light, a zoom module for regulating light intensity distribution of the sampling light on the to-be-irradiated ZnSe lens, and a closed-loop control module for controlling focal length of the zoom module, output power ratio and time sequence of the first light source module and the second light source module according to detection data of the detection module. The application can meet the demand of high-precision simulation and control of non-uniform light intensity distribution of CO2 laser irradiation of a ZnSe window mirror, and provides a high-stability and accurate irradiation solution for selection, optimization and reliability test of the ZnSe window mirror.

Description

Technical Field

[0001] This invention relates to the field of extreme ultraviolet lithography technology, and more specifically, to an apparatus and method for optimizing the non-uniformity of light intensity distribution in a ZnSe lens. Background Technology

[0002] In LPP-EUV lithography, the zinc selenide (ZnSe) window mirror, as a key optical component of the main-pump CO2 laser, requires high thermal stability and uniform intensity distribution. The main-pump CO2 laser is characterized by high repetition rate, short pulse width, and high power, and typically exhibits a Gaussian distribution with concentrated energy at the center. This results in a non-uniform intensity distribution on the ZnSe window mirror, easily leading to localized temperature rises that cause distortion or cracking, thus limiting further improvements in EUV light conversion efficiency and the long-term stability of the system.

[0003] Currently, common methods for simulating and optimizing the non-uniform light intensity distribution of ZnSe window mirrors include closed-loop control based on deep learning models, multi-focus phase modulation, microlens arrays, and adaptive optics.

[0004] However, the above schemes suffer from the contradiction between single-wavelength absorption rate and electro-optic efficiency, as well as the difficulty in decoupling light intensity and thermal effects, resulting in low laser electro-optic efficiency and complex thermal management. Summary of the Invention

[0005] The purpose of this invention is to provide a device and method for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, thereby solving at least one of the aforementioned technical problems. The specific solution is as follows: According to specific embodiments disclosed in this invention, a first aspect of this invention discloses an apparatus for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, comprising: The first light source module outputs the first laser to simulate the low absorption rate of the CO2 laser by the ZnSe lens to be irradiated. The second light source module outputs a second laser to simulate the thermal load of the ZnSe lens to be irradiated. The beam combining module combines the first laser and the second laser to obtain the sampled light; The beam splitting module splits the sampling light into a first sampling optical path and a second sampling optical path; The first detection module is set on the first sampling optical path and is used to detect the wavefront distortion and output power of the sampling light; The second detection module is set in the second sampling optical path, and the second sampling optical path is set with the ZnSe lens to be irradiated, for detecting the temperature of the ZnSe lens to be irradiated after being irradiated by the sampling light; A zoom module is disposed between the beam splitting module and the ZnSe lens to be irradiated, and adjusts the intensity distribution of the sampled light on the ZnSe lens to be irradiated. The closed-loop control module controls the focal length of the zoom module and the output power ratio and timing of the first light source module and the second light source module based on the detection data from the first detection module and the second detection module.

[0006] Optionally, both the first light source module and the second light source module are laser arrays formed by a plurality of laser units, wherein the laser units output Gaussian beams.

[0007] Optionally, the beam combining module includes: a common aperture beam combiner, a high-reflection beam splitter, and a high-transmission beam splitter. The high-reflectivity beam splitter is positioned after the first light source module, and the high-transmission beam splitter is positioned after the second light source module, so that the first laser and the second laser are incident on the common aperture beam combiner via different paths.

[0008] Optionally, the second light source module further includes an adjustable attenuator disposed after the laser array.

[0009] Optionally, the first detection module includes: an optical fiber temperature sensor disposed at the edge of the ZnSe lens to be irradiated.

[0010] According to specific embodiments disclosed in this invention, a second aspect of this invention discloses a method for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, comprising: Based on the parameters of the CO2 laser and the optical characteristics of the ZnSe lens to be irradiated, determine the number and arrangement of the laser units; The above-mentioned device for optimizing the non-uniformity of light intensity distribution in a ZnSe lens is constructed, and the focal length of the zoom module is adjusted so that the light intensity of the sampled light on the ZnSe lens to be irradiated exhibits a Gaussian distribution. A light-thermal multiphysics model is constructed. Based on the monitoring data of the first and second detection modules under irradiation conditions, the output power ratio and timing of the first and second light source modules are optimized through a closed-loop control module.

[0011] Optionally, determining the number and arrangement of laser units based on the parameters of the CO2 laser and the optical characteristics of the ZnSe lens to be irradiated includes: Construct an objective function based on the light intensity distribution after passing through the beam combining module, and optimize the objective function based on constraints to minimize the light intensity error of the objective function; The objective function is solved using the Lagrange multiplier method or quadratic programming algorithm to adjust the number and power of the laser units.

[0012] Optionally, the expression for optimizing the objective function is: The constraint is that the total power of the CO2 laser is conserved. Wavelength power allocation: , , Weight ; in, N The number of the laser units; Indicates the first i The aperture is in position The light intensity at that location; Indicates position The target light intensity at that location.

[0013] Optionally, the construction of the optical-thermal multiphysics model includes: By coupling light intensity and temperature field using the finite element method, the temperature field... To optimize light intensity, an additional constraint was established for the steady-state thermal equation of the ZnSe lens, and the temperature field was obtained through simulation. ; The power of the second laser is dynamically adjusted based on the real-time measured edge temperature.

[0014] Optionally, the focal length of the zoom module is adjusted so that the intensity of the sampled light on the ZnSe lens to be irradiated is distributed in a flat-top or multi-focal manner.

[0015] Compared with the prior art, the solutions disclosed in this invention have at least the following beneficial effects: This invention monitors the irradiation state of a ZnSe lens using wavefront and temperature sensors. Then, based on a deep learning algorithm, it constructs a photo-thermal multiphysics model, inputting data such as light intensity distribution and temperature field to optimize the power ratio and timing of lasers at different wavelengths. This ensures the total absorptivity matches the target value, and a closed-loop control module dynamically compensates for the non-uniformity, achieving a light intensity distribution error of ≤5%. This invention meets the high-precision simulation and control requirements for the non-uniform light intensity distribution of CO2 laser-irradiated ZnSe window lenses, providing a highly stable and precise irradiation solution for ZnSe window lens selection, optimization, and reliability testing. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure of this invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings: Figure 1 This is a schematic diagram of the overall structure of a device for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, provided in an embodiment of the present invention. Figure 2 This is a flowchart of a method for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, provided as an embodiment of the present invention.

[0017] Figure label: 1-First light source module, 2-Second light source module, 3-Collimating lens group, 4-Adjustable attenuator, 5-High-reflection beam splitter prism, 6-High-transmission beam splitter prism, 7-Common aperture beam combiner, 8-Beam splitter sampling mirror, 9-Dynamic focusing lens group, 10-ZnSe lens to be irradiated, 11-Reflector, 12-Wavefront sensor, 13-Power meter, 14-Fiber optic temperature sensor, 15-Closed-loop control module. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, a method and apparatus for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, as disclosed in this invention, will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments disclosed in this invention, and not all of them. Based on the embodiments disclosed in this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0019] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the application. The singular forms “a,” “said,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0020] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0021] It should be understood that although the terms first, second, third, etc., may be used to describe embodiments of this application, these terms should not be used in isolation. These terms are only used to distinguish between different terms. For example, first may also be referred to as second without departing from the scope of embodiments of this application, and similarly, second may also be referred to as first.

[0022] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the article or device that includes said element.

[0023] The following is in conjunction with the appendix Figure 1-2 Detailed description of optional embodiments of the present invention.

[0024] Example 1 like Figure 1 As shown in the figure, according to a specific embodiment of the present invention, the present invention provides an apparatus for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, comprising: The first light source module 1 outputs the first laser to simulate the low absorption rate of the CO2 laser by the ZnSe lens 10 to be irradiated.

[0025] The second light source module 2 outputs a second laser to simulate the thermal load of the ZnSe lens 10 to be irradiated.

[0026] In this embodiment, the ZnSe lens 10 is a ZnSe window mirror disposed in the radio frequency fast axial current CO2 laser. The first laser is a mid-infrared (3-5μm) laser, which can simulate the low absorption characteristics of ZnSe material to CO2 laser and undertake the main irradiation function. The second laser is a near-infrared 1μm wavelength laser, and the second light source module 2 has high electro-optic efficiency and fast dynamic control capability.

[0027] Specifically, both the first light source module 1 and the second light source module 2 are composed of several laser units arranged in an array, with each laser unit corresponding to a laser of a specific wavelength. In this embodiment, each laser unit in the first light source module 1 outputs mid-infrared laser light of the same wavelength, and each laser unit in the second light source module 2 outputs 1μm laser light, with each laser unit outputting a Gaussian beam. By arranging the laser units in an array, not only can the output power of each laser unit be controlled individually, but the arrangement of the laser units can also be adjusted according to the area of ​​the window mirror and the required light intensity distribution.

[0028] Furthermore, the output power of the first light source module 1 and the second light source module 2 can be adjusted by an internal power supply or by an external optical element, such as an adjustable attenuator.

[0029] As an optional implementation, the first laser emitted from the first light source module is collimated using the collimating lens group 3.

[0030] The beam combining module combines the first laser and the second laser to obtain the sampled light.

[0031] Specifically, the beam combining module includes: a high-reflectivity beam splitter 5, a high-transmission beam splitter 6, and a common-aperture beam combiner 7. The high-reflectivity beam splitter 5 is positioned after the first light source module 1, reflecting the first laser beam into the first optical path. The high-transmission beam splitter 6 is positioned after the second light source module 2, projecting the second laser beam into the second optical path. The beams are combined by the common-aperture beam combiner 7, located at the intersection of the first and second optical paths, to output a mixed-wavelength sampling light.

[0032] In this embodiment, the high-reflection beam splitter 5 and the high-transmission beam splitter 6 are respectively a hierarchical high-reflection beam splitter prism and a hierarchical high-transmission beam splitter prism, and the first laser and the second laser are combined in different optical paths to avoid interference caused by the direct mixing of the two wavelengths, such as thermal damage or energy loss.

[0033] As an alternative implementation, a diffraction grating or metasurface can be used to combine beams of different wavelengths into the same optical path to simulate a Gaussian distribution.

[0034] The beam splitting module splits the sampling light into a first sampling optical path and a second sampling optical path.

[0035] Specifically, the beam splitting module is a beam splitting sampling mirror 8, which proportionally guides the sampling light into the first detection module set in the first sampling optical path and the second detection module set in the second sampling optical path.

[0036] In this embodiment, the first detection module is used to detect the wavefront distortion and output power of the sampled light, and includes: a wavefront sensor 12 and a power meter 13.

[0037] A ZnSe lens 10 to be irradiated is arranged on the second sampling optical path. The second detection module is set at the edge of the ZnSe lens 10 to be irradiated, and is used to detect the edge temperature of the ZnSe lens 10 after being irradiated by the sampling light. The edge temperature of the ZnSe lens 10 to be irradiated can be obtained using an optical fiber temperature sensor.

[0038] A zoom module is disposed between the beam splitting module and the ZnSe lens 10 to be irradiated, and adjusts the light intensity distribution of the sampled light on the ZnSe lens 10 to be irradiated.

[0039] Specifically, the zoom module uses a dynamic focusing lens group 9, which has an electric zoom function and can accurately focus mixed wavelength sampling light onto the same spot to realize the Gaussian distribution simulation of CO2 laser.

[0040] As an optional implementation, a multi-focus, flat-top, or other programmable light field can also be achieved through a zoom module.

[0041] The closed-loop control module 15 controls the focal length of the zoom module, the output power ratio and timing of the first light source module and the second light source module based on the detection data of the first detection module and the second detection module.

[0042] In this embodiment, the closed-loop control module 15 receives the light intensity value input from the wavefront sensor 12, the power value input from the power meter 13, and the temperature value input from the fiber optic temperature sensor 14. Based on the embedded optimization algorithm, it outputs a heat load adjustment command to the adjustable attenuator 4, a power balance command to the mid-infrared laser unit 1, and a distortion correction command to the dynamic focusing lens group 9, thereby meeting the high-precision simulation and control requirements of the non-uniform light intensity distribution of the CO2 laser irradiated ZnSe window mirror.

[0043] This invention solves the physical limitations of single-wavelength systems by constructing mid-infrared and near-infrared laser arrays to simulate the Gaussian distribution of CO2 laser irradiation on a ZnSe window mirror. Simultaneously, based on real-time irradiation state monitoring and deep learning algorithms, the power ratio and timing of each wavelength laser are optimized and fed back to the mid-infrared laser unit, adjustable attenuator, and dynamic focusing lens group to compensate for dynamic disturbances, improving the control accuracy of non-uniform light intensity distribution. Furthermore, the device supports multi-focal and flat-top programmable light field generation, providing an efficient, low-heat, and highly stable solution for high-power laser applications in various fields.

[0044] Example 2 The present invention also provides method embodiments in combination with the above embodiments. The interpretation of the same name meaning is the same as that of the above embodiments, and the same technical effects are achieved as those of the above embodiments. Therefore, they will not be repeated here.

[0045] like Figure 2 As shown, this invention discloses a method for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, comprising the following steps: Step S100: Determine the number and arrangement of laser units based on the parameters of the CO2 laser and the optical characteristics of the ZnSe lens to be irradiated.

[0046] Step S200: Construct the above-mentioned device for optimizing the non-uniformity of light intensity distribution of the ZnSe lens, and adjust the focal length of the zoom module so that the light intensity of the sampled light on the ZnSe lens to be irradiated presents a Gaussian distribution.

[0047] Step S300: Construct a light-thermal multiphysics model. Based on the monitoring data of the first and second detection modules under irradiation conditions, optimize the output power ratio and timing of the first and second light source modules through a closed-loop control module.

[0048] The step S100, which involves determining the number and arrangement of laser units based on the parameters of the CO2 laser and the optical characteristics of the ZnSe lens to be irradiated, includes: Step S101: Construct an objective function based on the light intensity distribution after passing through the beam combining module, and optimize the objective function based on the constraints to minimize the light intensity error of the objective function.

[0049] Specifically, the ZnSe lens to be irradiated is a window mirror of a CO2 laser. Based on parameters such as CO2 laser power, repetition rate, pulse width, intensity mode, and spot diameter, as well as parameters such as the aperture, geometric dimensions, and water-cooling area of ​​the ZnSe window mirror, the laser units in the first and second light source modules are geometrically arranged. In this embodiment, the laser units in the first and second light source modules adopt the same geometric layout.

[0050] First, 1000 sampling points are taken within the aperture of the ZnSe window mirror for discretization sampling.

[0051] Then, a matrix is ​​constructed, and the light intensity at each sampling point at each sub-aperture is calculated. Each sub-aperture outputs a Gaussian beam, and the total light intensity is then calculated. The expression for the superposition of light intensities from each sub-aperture is: in, For the first i Individual aperture power, For the first i Individual aperture beam radius, The coordinates of the sub-aperture center are r This represents a two-dimensional position coordinate vector on the observation plane.

[0052] Since the intensity distribution of the sampled light is Gaussian, let's establish the objective function... If the optimization objective is to minimize the light intensity error, then the optimization objective function is as follows: The constraint is that the total power of the CO2 laser is conserved. Wavelength power allocation , , Weight ; in,N The number of the laser units; Indicates the first i The aperture is in position The light intensity at that location; Indicates position The target light intensity at that location.

[0053] Step S102: Solve the objective function using the Lagrange multiplier method or quadratic programming algorithm to adjust the number and power of the laser units.

[0054] Specifically, the quadratic programming solver is called to calculate the optimal weights. The geometric layout of the laser unit is adjusted by increasing or decreasing the number of sub-apertures based on the error distribution.

[0055] Based on the optimization algorithm results, Zemax software was used to simulate the light intensity distribution, and the output power of the laser unit was adjusted to meet the requirement of error ≤5%. The error was calculated as follows: In step S200, the focal length of the dynamic focusing lens group can also be adjusted to generate a multifocal, flat-top, or Gaussian distributed light field.

[0056] In step S300, a light-thermal multiphysics model is constructed based on a deep learning algorithm. Light intensity distribution and temperature field data are input, and the power ratio and timing of lasers of each wavelength are optimized to match the total absorption rate with the target value. Through PID dynamic compensation, the light intensity distribution error is ≤5%.

[0057] Specifically, considering the influence of thermal effects, a combined thermal-optical intensity simulation was conducted. It is known that the absorption rate of the ZnSe window mirror for mid-infrared wavelengths in the 3-5 μm range is... The absorption rate at a near-infrared wavelength of 1μm is Then the total absorption power density of the mixed wavelength laser As shown in the following formula: in, and The light intensity distributions are shown for the mid-infrared and near-infrared regions, respectively.

[0058] Furthermore, the temperature field As an additional constraint for light intensity optimization, the steady-state thermal equation for the ZnSe window mirror is expressed as follows: in, k The value represents the thermal conductivity of ZnSe material.

[0059] Couple light intensity and temperature field using the finite element method T( r This enables multi-objective optimization of light intensity and temperature rise.

[0060] Based on this, a temperature sensor was used to measure the edge temperature of the ZnSe window mirror. The near-infrared power is dynamically adjusted as shown in the following formula: in, The initial power of the near-infrared wavelength laser; The target temperature is calculated after co-simulation of thermal and optical intensity. This is the proportionality coefficient.

[0061] This allows the hybrid wavelength laser array to simulate light intensity distribution while also making the temperature gradient of the ZnSe window mirror close to the actual working conditions.

[0062] The adjustable attenuator is dynamically adjusted based on the real-time measured edge temperature of the ZnSe window mirror, thereby regulating the second laser power. hour, The system reaches a steady state of thermal-optical intensity.

[0063] This embodiment optimizes the non-uniformity of light intensity distribution in ZnSe lenses by integrating mid-infrared (3-5 μm) and near-infrared (1 μm) lasers to simulate the non-uniform light intensity distribution characteristics of CO2 lasers (10.6 μm) on ZnSe window mirrors, while overcoming the limitations of single-wavelength systems. Specifically, the mid-infrared laser is used to simulate the low absorption rate (approximately 0.5%) of CO2 lasers in ZnSe material, undertaking the main irradiation function; combined with the efficient dynamic modulation capability of near-infrared lasers, different wavelength beams are combined into the same optical path through spectral synthesis technology, overcoming the physical limitations of single-wavelength laser systems. Regarding dynamic collaborative control and light intensity distribution optimization, the system adopts a real-time feedback control mechanism, monitoring the irradiation state of the ZnSe window mirror through light intensity distribution sensors (such as CCDs or wavefront sensors) and temperature sensors; then, a photo-thermal multiphysics model is constructed based on deep learning algorithms. In terms of dynamic collaborative control and light intensity distribution optimization, the system adopts a real-time feedback control mechanism. It monitors the irradiation state of the ZnSe window mirror using light intensity distribution sensors (such as CCDs or wavefront sensors) and temperature sensors. Then, based on deep learning algorithms, it constructs a photo-thermal multiphysics model, inputting light intensity distribution and temperature field data to optimize the power ratio and timing of lasers at each wavelength. It outputs distortion correction commands to the dynamic focusing lens group, matching the total absorptivity to the target value. This meets the high-precision simulation and control requirements for the non-uniform light intensity distribution of the CO2 laser irradiated ZnSe window mirror. This further improves pump light utilization and enhances multiphysics collaborative control capabilities, providing a highly stable and precise irradiation solution for ZnSe window mirror selection, optimization, and reliability testing.

[0064] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0065] The above embodiments are only used to illustrate the technical solutions disclosed in this invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments disclosed in this invention.

Claims

1. A device for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, characterized in that, include: The first light source module outputs the first laser to simulate the low absorption rate of the CO2 laser by the ZnSe lens to be irradiated. The second light source module outputs a second laser to simulate the thermal load of the ZnSe lens to be irradiated. The beam combining module combines the first laser and the second laser to obtain the sampled light; The beam splitting module splits the sampling light into a first sampling optical path and a second sampling optical path; The first detection module is set on the first sampling optical path and is used to detect the wavefront distortion and output power of the sampling light; The second detection module is set in the second sampling optical path, and the second sampling optical path is set with the ZnSe lens to be irradiated, for detecting the temperature of the ZnSe lens to be irradiated after being irradiated by the sampling light; A zoom module is disposed between the beam splitting module and the ZnSe lens to be irradiated, and adjusts the intensity distribution of the sampled light on the ZnSe lens to be irradiated. The closed-loop control module controls the focal length of the zoom module and the output power ratio and timing of the first light source module and the second light source module based on the detection data from the first detection module and the second detection module.

2. The apparatus according to claim 1, characterized in that, Both the first light source module and the second light source module are laser arrays formed by several laser units, and the laser units output Gaussian beams.

3. The apparatus according to claim 1, characterized in that, The beam combining module includes: a common aperture beam combiner, a high-reflection beam splitter, and a high-transmission beam splitter. The high-reflectivity beam splitter is positioned after the first light source module, and the high-transmission beam splitter is positioned after the second light source module, so that the first laser and the second laser are incident on the common aperture beam combiner via different paths.

4. The apparatus according to claim 2, characterized in that, The second light source module further includes an adjustable attenuator, which is disposed after the laser array.

5. The apparatus according to claim 1, characterized in that, The first detection module includes: an optical fiber temperature sensor, which is disposed at the edge of the ZnSe lens to be irradiated.

6. A method for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, characterized in that, include: Based on the parameters of the CO2 laser and the optical characteristics of the ZnSe lens to be irradiated, determine the number and arrangement of the laser units; A device for optimizing the non-uniformity of light intensity distribution in a ZnSe lens as described in any one of claims 1-5 is constructed, and the focal length of the zoom module is adjusted so that the light intensity of the sampled light on the ZnSe lens to be irradiated exhibits a Gaussian distribution. A light-thermal multiphysics model is constructed. Based on the monitoring data of the first and second detection modules under irradiation conditions, the output power ratio and timing of the first and second light source modules are optimized through a closed-loop control module.

7. The method according to claim 6, characterized in that, The determination of the number and arrangement of laser units based on the parameters of the CO2 laser and the optical characteristics of the ZnSe lens to be irradiated includes: Construct an objective function based on the light intensity distribution after passing through the beam combining module, and optimize the objective function based on constraints to minimize the light intensity error of the objective function; The objective function is solved using the Lagrange multiplier method or quadratic programming algorithm to adjust the number and power of the laser units.

8. The method according to claim 7, characterized in that, The expression for optimizing the objective function is as follows: ； The constraint is that the total power of the CO2 laser is conserved. ; Wavelength power allocation: , , Weight ; in, N The number of the laser units; Indicates the first i The aperture is in position The light intensity at that location; Indicates position The target light intensity at that location; M is the number of sampling points; MIR is the first laser output by the first light source module, and the first laser is a mid-infrared laser; NIR is the second laser output from the second light source module. The second laser is a near-infrared laser with a wavelength of 1μm.

9. The method according to claim 6, characterized in that, The construction of the optical-thermal multiphysics model includes: By coupling light intensity and temperature field using the finite element method, the temperature field... To optimize light intensity, an additional constraint was established for the steady-state thermal equation of the ZnSe lens, and the temperature field was obtained through simulation. ; The power of the second laser is dynamically adjusted based on the real-time measured edge temperature.

10. The method according to claim 6, characterized in that, The focal length of the zoom module is adjusted so that the intensity of the sampled light on the ZnSe lens to be irradiated is distributed in a flat-top or multi-focal manner.

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