Device and method for optimizing light intensity distribution heterogeneity of ZnSe lens

Abstract

The invention discloses a device and method for optimizing light intensity distribution heterogeneity of a ZnSe lens, and the device comprises a first light source module which is used for simulating the low absorption rate of a to-be-irradiated ZnSe lens to CO2 laser; the second light source module is used for simulating a thermal load of the ZnSe lens to be irradiated; the beam combining module is used for combining to obtain sampling light with mixed wavelengths; the detection module is used for detecting wavefront distortion and output power of the sampling light and the temperature of the to-be-irradiated ZnSe lens irradiated by the sampling light; the zoom module is used for regulating and controlling the light intensity distribution of the sampling light on the ZnSe lens to be irradiated; and the closed-loop control module is used for controlling the focal length of the zooming module and the 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. According to the invention, the requirements of high-precision simulation and control of non-uniform light intensity distribution of the ZnSe window mirror irradiated by CO2 laser can be met, and a high-stability precise irradiation solution is provided for model selection, optimization and reliability test of the ZnSe window mirror.

Description

Technical Field

[0001] The present invention relates to the technical field of extreme ultraviolet lithography, and in particular to a device and method for optimizing the non-uniformity of light intensity distribution of a ZnSe lens. Background Art

[0002] In LPP-EUV lithography, zinc selenide (ZnSe) windows, key optical components of the main pump CO2 laser, require high thermal stability and uniform light intensity distribution. The main pump CO2 laser features 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 light intensity distribution on the ZnSe window, which can easily cause localized temperature rise, leading to distortion or cracking. This hinders further improvements in EUV light conversion efficiency and the long-term stability of the system.

[0003] In the field of EUV lithography, import restrictions on RF fast axial flow CO2 lasers with a power of 15kW or higher have hindered the domestic development of EUV lithography systems by fully addressing the potential risks and issues of non-uniform intensity distribution in the main pump CO2 laser. Currently, methods such as closed-loop control based on deep learning models, multi-focus phase modulation, microlens arrays, and adaptive optics are commonly used to simulate and optimize the non-uniform intensity distribution of ZnSe windows.

[0004] However, the above scheme has the problem of contradiction between single wavelength absorption rate and electro-optical efficiency and difficulty in decoupling light intensity-thermal effect, resulting in low laser electro-optical efficiency and complex thermal management. Summary of the Invention

[0005] The purpose of the present invention is to provide a device and method for optimizing the non-uniformity of light intensity distribution in a ZnSe lens, which can solve at least one of the above-mentioned technical problems. The specific solution is as follows:

[0006] According to a specific embodiment disclosed in the present invention, a first aspect of the present invention discloses a device for optimizing the non-uniformity of light intensity distribution of a ZnSe lens, comprising:

[0007] The first light source module outputs a first laser to simulate the low absorption rate of the ZnSe lens to be irradiated to the CO2 laser;

[0008] A second light source module outputs a second laser to simulate the thermal load of the ZnSe lens to be irradiated;

[0009] a beam combining module, combining the first laser and the second laser to obtain sampling light;

[0010] A light splitting module, which splits the sampling light into a first sampling light path and a second sampling light path;

[0011] a first detection module, disposed on the first sampling optical path, for detecting the wavefront distortion and output power of the sampling light;

[0012] a second detection module, disposed on the second sampling optical path, where the ZnSe lens to be irradiated is disposed, and configured to detect the temperature of the ZnSe lens to be irradiated after being irradiated by the sampling light;

[0013] A zoom module, disposed between the light splitting module and the ZnSe lens to be irradiated, for adjusting the intensity distribution of the sampling light on the ZnSe lens to be irradiated;

[0014] A 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 according to the detection data of the first detection module and the second detection module.

[0015] Optionally, both the first light source module and the second light source module are laser arrays formed by a plurality of laser units, and the laser units output Gaussian beams.

[0016] Optionally, the beam combining module includes: a common aperture beam combining mirror, a high reflection beam splitting prism and a high transmission beam splitting prism.

[0017] The high-reflection beam splitter prism is arranged behind the first light source module, and the high-transmission beam splitter prism is arranged behind the second light source module, so that the first laser and the second laser are respectively incident on the common-aperture beam combiner through different paths.

[0018] Optionally, the second light source module further includes: an adjustable attenuator, which is arranged after the laser array.

[0019] Optionally, the first detection module includes: an optical fiber temperature sensor, and the optical fiber temperature sensor is arranged at the edge of the ZnSe lens to be irradiated.

[0020] According to a specific embodiment disclosed in the present invention, a second aspect of the present invention discloses a method for optimizing the non-uniformity of light intensity distribution of a ZnSe lens, comprising:

[0021] Determine the number and arrangement of laser units based on the parameters of the CO2 laser and the optical properties of the ZnSe lens to be irradiated;

[0022] Build the above-mentioned device for optimizing the non-uniformity of the light intensity distribution of the ZnSe lens, and adjust the focal length of the zoom module so that the intensity of the sampling light on the ZnSe lens to be irradiated has a Gaussian distribution;

[0023] A light-heat multi-physics field model is constructed, and based on the monitoring data of the first detection module and the second detection module in the irradiation state, the output power ratio and timing of the first light source module and the second light source module are optimized through a closed-loop control module.

[0024] Optionally, determining the number and arrangement of laser units according to the parameters of the CO2 laser and the optical properties of the ZnSe lens to be irradiated includes:

[0025] Constructing an objective function based on the light intensity distribution after passing through the beam combining module, and optimizing the objective function based on constraints to minimize the light intensity error of the objective function;

[0026] The objective function is solved using a Lagrange multiplier method or a quadratic programming algorithm to adjust the number and power of the laser units.

[0027] Optionally, the expression for optimizing the objective function is:

[0028]

[0029] The constraints are: CO2 laser total power conservation

[0030] Wavelength power allocation: ∑ MIR k i =m1,∑ NIR k i =m2, m1+m2=1; weight k i ≥0;

[0031] Wherein, N is the number of the laser units;

[0032] I i (r j ) indicates that the i-th subaperture is at position r j The light intensity at

[0033] I target (r j ) represents the position r j The target light intensity at .

[0034] Optionally, constructing the light-heat multi-physics model includes:

[0035] The light intensity and temperature field are coupled by the finite element method, and the temperature field T(r) is taken as an additional constraint for light intensity optimization to establish the steady-state thermal equation of the ZnSe lens and obtain the temperature field T(r);

[0036] The second laser power is dynamically adjusted according to the edge temperature measured in real time.

[0037] Optionally, the focal length of the zoom module is adjusted so that the intensity of the sampling light on the ZnSe lens to be irradiated has a flat-top distribution or a multi-focal distribution.

[0038] Compared with the prior art, the above solution of the embodiment disclosed in the present invention has at least the following beneficial effects:

[0039] This method uses a wavefront sensor and a temperature sensor to monitor the irradiation status of the ZnSe lens. It then constructs a light-heat multi-physics field model based on a deep learning algorithm. By inputting data such as light intensity distribution and temperature field, it optimizes the power ratio and timing of each wavelength laser to match the total absorptivity with the target value. Dynamically compensates for this through a closed-loop control module, achieving a non-uniformity requirement of ≤5% in intensity distribution error. This method meets the requirements for high-precision simulation and control of the non-uniform light intensity distribution of CO2 laser-irradiated ZnSe windows, providing a highly stable and precise irradiation solution for ZnSe window lens selection, optimization, and reliability testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings are incorporated into and constitute a part of the specification, illustrating embodiments consistent with the present disclosure and, together with the specification, explaining the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and those skilled in the art can derive other drawings based on these drawings without inventive effort. In the drawings:

[0041] Figure 1 A schematic diagram of the overall structure of a device for optimizing the non-uniformity of light intensity distribution in a ZnSe lens provided by an embodiment of the present invention;

[0042] Figure 2 This is a flow chart of a method for optimizing the non-uniformity of light intensity distribution of a ZnSe lens provided by an embodiment of the present invention.

[0043] Reference numerals:

[0044] 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 splitting 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 DESCRIPTION

[0045] To further clarify the objectives, technical solutions, and advantages of the present invention, the following describes in further detail, with reference to the accompanying drawings, a method and apparatus for optimizing the non-uniformity of light intensity distribution in a ZnSe lens. Obviously, the described embodiments represent only a portion of the embodiments disclosed herein, and not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments disclosed herein without inventive effort are intended to fall within the scope of protection of the present invention.

[0046] The terms used in the examples of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms "a," "the," and "the" used in the examples of this application and the appended claims are also intended to include plural forms, and unless the context clearly indicates otherwise, "a plurality" generally includes at least two.

[0047] It should be understood that the term "and / or" as used herein is merely a description of the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0048] It should be understood that although the terms first, second, third, etc. may be used to describe in the embodiments of the present application, these should not be limited to these terms. These terms are only used to distinguish. For example, without departing from the scope of the embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first.

[0049] It should also be noted that the terms "include," "comprises," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a product or device comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such product or device. In the absence of further limitations, an element defined by the phrase "comprising a" does not exclude the presence of other identical elements in the product or device comprising the element.

[0050] The following is combined with Figure 1-2 Alternative embodiments of the present invention are described in detail.

[0051] Example 1

[0052] like Figure 1 As shown, according to a specific embodiment of the present invention, the present invention provides a device for optimizing the non-uniformity of light intensity distribution of a ZnSe lens, comprising:

[0053] The first light source module 1 outputs a first laser for simulating the low absorption rate of the ZnSe lens 10 to be irradiated to the CO2 laser.

[0054] The second light source module 2 outputs a second laser to simulate the heat load of the ZnSe lens 10 to be irradiated.

[0055] In this embodiment, the ZnSe lens 10 is a ZnSe window lens installed in an RF fast axial flow CO2 laser. The first laser is a mid-infrared laser (3-5μm), which can simulate the low absorption characteristics of ZnSe materials for CO2 lasers and perform the primary irradiation function. The second laser is a near-infrared laser with a wavelength of 1μm, and the second light source module 2 has high electro-optical efficiency and fast dynamic control capabilities.

[0056] Specifically, the first light source module 1 and the second light source module 2 are each composed of a plurality of laser units arranged in an array, each laser unit corresponding to a laser of a corresponding wavelength. In this embodiment, each laser unit in the first light source module 1 outputs a mid-infrared laser of the same wavelength, and each laser unit in the second light source module 2 outputs a 1μm laser, and the laser beam output by each laser unit is a Gaussian beam. By arranging the laser units in an array, not only can the light output power of each laser unit be individually controlled, 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.

[0057] 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.

[0058] As an optional implementation, the collimating lens group 3 is used to collimate the first laser emitted by the first light source module.

[0059] The beam combining module combines the first laser beam and the second laser beam to obtain sampling light.

[0060] Specifically, the beam combining module includes: a high-reflection beam splitter prism 5, a high-transmittance beam splitter prism 6, and a common-aperture beam combiner 7. The high-reflection beam splitter prism 5 is arranged after the first light source module 1 and reflects the first laser light to the first optical path. The high-transmittance beam splitter prism 6 is arranged after the second light source module 2 and projects the second laser light to the second optical path. The common-aperture beam combiner 7, which is arranged at the intersection of the first and second optical paths, combines the beams and outputs sampling light of mixed wavelengths.

[0061] In this embodiment, the high-reflection beam splitter prism 5 and the high-transmission beam splitter prism 6 are respectively a hierarchical high-reflection beam splitter prism and a hierarchical high-transmission beam splitter prism, and respectively combine the first laser and the second laser on different optical paths to avoid interference caused by direct mixing of the two wavelengths, such as thermal damage or energy loss.

[0062] As an optional implementation, a diffraction grating or a metasurface can be used to combine light beams of different wavelengths into the same optical path to simulate a Gaussian distribution.

[0063] The light splitting module splits the sampling light into a first sampling light path and a second sampling light path.

[0064] Specifically, the spectroscopic module is a spectroscopic sampling mirror 8, which introduces the sampling light into the first detection module arranged in the first sampling light path and the second detection module arranged in the second sampling light path in proportion.

[0065] In this embodiment, the first detection module is used to detect the wavefront distortion and output power of the sampling light, and includes a wavefront sensor 12 and a power meter 13 .

[0066] A ZnSe lens 10 to be irradiated is provided on the second sampling optical path. A second detection module is provided at the edge of the ZnSe lens 10 to be irradiated to detect the edge temperature of the ZnSe lens 10 after being irradiated by the sampling light. An optical fiber temperature sensor can be used to obtain the edge temperature of the ZnSe lens 10 to be irradiated.

[0067] The zoom module is provided between the light splitting module and the ZnSe lens 10 to be irradiated, and adjusts the light intensity distribution of the sampling light on the ZnSe lens 10 to be irradiated.

[0068] Specifically, the zoom module adopts a dynamic focusing lens group 9 with an electric zoom function, which can accurately focus the mixed wavelength sampling light to the same light spot, realizing the Gaussian distribution simulation of CO2 laser.

[0069] As an optional implementation, a zoom module can also be used to realize programmable light fields such as multi-focus and flat top.

[0070] The closed-loop control module 15 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 according to the detection data of the first detection module and the second detection module.

[0071] In this embodiment, the closed-loop control module 15 receives the light intensity value input by the wavefront sensor 12, the power value input by the power meter 13, and the temperature value input by the optical fiber temperature sensor 14, and based on the embedded optimization algorithm, outputs a thermal load adjustment instruction to the adjustable attenuator 4, outputs a power balance instruction to the mid-infrared laser unit 1, and outputs a distortion correction instruction to the dynamic focusing lens group 9, thereby meeting the requirements of high-precision simulation and control of the non-uniform light intensity distribution of the CO2 laser irradiated ZnSe window mirror.

[0072] This invention overcomes the physical limitations of single-wavelength systems by constructing a mid-infrared and near-infrared laser array to simulate the Gaussian distribution of CO2 laser irradiation on a ZnSe window mirror. Simultaneously, based on real-time irradiation status monitoring and a deep learning algorithm, the power ratio and timing of each wavelength laser are optimized. This feedback is fed back to the mid-infrared laser unit, the adjustable attenuator, and the dynamic focusing lens system to compensate for dynamic disturbances, improving the control accuracy of non-uniform light intensity distribution. Furthermore, the device supports programmable light field generation, including multi-focus and flat-top options, providing a high-efficiency, low-heat, and high-stability solution for high-power laser applications in various fields.

[0073] Example 2

[0074] The present invention also provides method embodiments combined with the above embodiments. The explanations based on the same name meanings are the same as those of the above embodiments, and have the same technical effects as the above embodiments, which will not be repeated here.

[0075] like Figure 2 As shown, the present invention discloses a method for optimizing the non-uniformity of light intensity distribution of a ZnSe lens, comprising the following steps:

[0076] Step S100: Determine the number and arrangement of laser units according to the parameters of the CO2 laser and the optical properties of the ZnSe lens to be irradiated.

[0077] Step S200 , constructing the above-mentioned device for optimizing the non-uniformity of the light intensity distribution of the ZnSe lens, and adjusting the focal length of the zoom module so that the intensity of the sampling light on the ZnSe lens to be irradiated has a Gaussian distribution.

[0078] Step S300: construct a light-heat multi-physics field model, and optimize the output power ratio and timing of the first light source module and the second light source module through a closed-loop control module based on the monitoring data of the first detection module and the second detection module in the irradiation state.

[0079] The step of determining the number and arrangement of laser units according to the parameters of the CO2 laser and the optical properties of the ZnSe lens to be irradiated in step S100 includes:

[0080] Step S101: constructing an objective function based on the light intensity distribution after passing through the beam combining module, and optimizing the objective function based on constraint conditions to minimize the light intensity error of the objective function.

[0081] Specifically, the ZnSe lens to be irradiated serves as the window mirror of a CO2 laser. The geometric layout of the laser units in the first and second light source modules is determined based on parameters such as the CO2 laser power, repetition rate, pulse width, intensity pattern, and spot diameter, as well as parameters such as the optical aperture, geometric dimensions, and water cooling area of ​​the ZnSe window mirror. In this embodiment, the laser units in the first and second light source modules employ the same geometric layout.

[0082] First, 1000 sampling points are taken within the aperture of the ZnSe window mirror for discretized sampling.

[0083] Then, a matrix is ​​constructed to calculate the light intensity of each sampling point at each sub-aperture. Each sub-aperture outputs a Gaussian beam, so the total light intensity I total (r) is the superposition of the light intensities of each sub-aperture, and its expression is:

[0084]

[0085] Among them, P i is the i-th subaperture power, ω i is the radius of the i-th sub-aperture beam,

[0086] r i is the coordinate of the center of the sub-aperture, and r represents the two-dimensional position coordinate vector on the observation plane.

[0087] Since the sampling light intensity distribution is Gaussian, the objective function I is set target (r), the optimization goal is to minimize the light intensity error, so the optimization objective function is as follows:

[0088]

[0089] The constraints are: the total power of CO2 laser is conserved

[0090] Wavelength power allocation∑ MIR k i =m1,∑ NIR k i =m2, m1+m2=1; weight k i ≥0;

[0091] Wherein, N is the number of the laser units;

[0092] I i (r j ) indicates that the i-th subaperture is at position r j The light intensity at

[0093] I target (r j ) represents the position r jThe target light intensity at .

[0094] Step S102: using a Lagrange multiplier method or a quadratic programming algorithm to solve the objective function and thereby adjust the number and power of the laser units.

[0095] Specifically, call the quadratic programming solver to calculate the optimal weight k i , the geometric layout of the laser unit is adjusted by increasing or decreasing the number of sub-apertures according to the error distribution.

[0096] According to the results of the optimization algorithm, Zemax software is used to simulate the light intensity distribution and adjust the output power of the laser unit to meet the requirement of error ≤ 5%. The error is calculated as follows:

[0097]

[0098] In step S200 , the focal length of the dynamic focusing lens group may be adjusted to generate a multi-focal, flat-top or Gaussian distribution light field.

[0099] In step S300, a light-heat multi-physics field model is constructed based on a deep learning algorithm, and the light intensity distribution and temperature field data are input to optimize the power ratio and timing of each wavelength laser so that the total absorption rate matches the target value. Through PID dynamic compensation, the light intensity distribution error is achieved to be ≤5%.

[0100] Specifically, the thermal effect is further considered and the thermal-light intensity collaborative simulation is carried out. It is known that the absorption rate of the ZnSe window mirror for the 3-5μm mid-infrared wavelength is α MIR The absorption rate of 1μm near-infrared wavelength is α NIR , then the total absorbed power density Q(r) of the mixed wavelength laser is as follows:

[0101] Q(r)=α MIR I MIR +α NIR I NIR (2);

[0102] Among them, I MIR and I NIR These are the light intensity distributions of mid-infrared and near-infrared, respectively.

[0103] Furthermore, the temperature field T(r) is used as an additional constraint for light intensity optimization, and the steady-state thermal equation of the ZnSe window mirror is established as follows:

[0104]

[0105] Wherein, k is the thermal conductivity of ZnSe material.

[0106] The light intensity and temperature field T(r) are coupled by the finite element method to achieve multi-objective optimization of light intensity and temperature rise.

[0107] On this basis, a temperature sensor is used to measure the edge temperature T of the ZnSe window mirror. edge , dynamically adjust the near-infrared power as shown in the following formula:

[0108] P NIR =P NIR，0 [1+β·(T edge -T target )](4);

[0109] Among them, P NIR,0 is the initial power of the near-infrared wavelength laser;

[0110] T target is the target temperature calculated after thermal-light intensity collaborative simulation, and β is the proportional coefficient.

[0111] This allows the mixed-wavelength laser array to simulate the light intensity distribution and make the temperature gradient of the ZnSe window mirror close to the actual working conditions.

[0112] The adjustable attenuator is dynamically adjusted according to the real-time measured ZnSe window mirror edge temperature, thereby adjusting the second laser power. edge =T target When P NIR =P NIR，0 , the system reaches a thermal-light intensity steady state.

[0113] The method for optimizing the non-uniformity of the light intensity distribution of the ZnSe lens in this embodiment integrates mid-infrared (3-5μm) and near-infrared (1μm) lasers to simulate the non-uniform light intensity distribution characteristics of the CO2 laser (10.6μm) on the ZnSe window mirror, while overcoming the limitations of the single-wavelength system. Specifically, the mid-infrared laser is used to simulate the low absorption rate (about 0.5%) of the CO2 laser in the ZnSe material, which takes on the main irradiation function; combined with the efficient dynamic modulation capability of the near-infrared laser, the spectrum synthesis technology is used to combine light beams of different wavelengths into the same optical path, breaking through the physical limitations of the single-wavelength laser system. In terms of dynamic collaborative control and light intensity distribution optimization, the system adopts a real-time feedback control mechanism to monitor the irradiation state of the ZnSe window mirror through light intensity distribution sensors (such as CCD or wavefront sensors) and temperature sensors; then, a light-thermal multi-physics field model is constructed based on a deep learning algorithm. In terms of dynamic collaborative control and light intensity distribution optimization, the system adopts a real-time feedback control mechanism, monitoring the irradiation status of the ZnSe window mirror through light intensity distribution sensors (such as CCD or wavefront sensors) and temperature sensors. Then, based on a deep learning algorithm, a light-thermal multi-physics field model is constructed, inputting light intensity distribution and temperature field data to optimize the power ratio and timing of each wavelength laser. Distortion correction instructions are output to the dynamic focusing lens group to match the total absorption rate with the target value, meeting the requirements for high-precision simulation and control of the non-uniform light intensity distribution of CO2 laser irradiated ZnSe window mirrors. This further improves the utilization rate of pump light and enhances the multi-physics field collaborative control capabilities, providing a highly stable and precise irradiation solution for ZnSe window mirror selection, optimization, and reliability testing.

[0114] 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. References to the common and similar parts between the various embodiments will be sufficient. For the systems or devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, their descriptions are relatively simple; for relevant details, refer to the descriptions of the methods.

[0115] The above embodiments are only used to illustrate the technical solutions disclosed in the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments disclosed in the present invention.

Claims

1. A device for optimizing the non-uniformity of light intensity distribution of a ZnSe lens, characterized in that: include: The first light source module outputs a first laser to simulate the low absorption rate of the ZnSe lens to be irradiated to the CO2 laser; A second light source module outputs a second laser to simulate the thermal load of the ZnSe lens to be irradiated; a beam combining module, combining the first laser and the second laser to obtain sampling light; A light splitting module, which splits the sampling light into a first sampling light path and a second sampling light path; a first detection module, disposed on the first sampling optical path, for detecting the wavefront distortion and output power of the sampling light; a second detection module, disposed on the second sampling optical path, where the ZnSe lens to be irradiated is disposed, and configured to detect the temperature of the ZnSe lens to be irradiated after being irradiated by the sampling light; A zoom module, disposed between the light splitting module and the ZnSe lens to be irradiated, for adjusting the intensity distribution of the sampling light on the ZnSe lens to be irradiated; A 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 according to the detection data of the first detection module and the second detection module.

2. The device according to claim 1, characterized in that The first light source module and the second light source module are both laser arrays formed by a plurality of laser units, and the laser units output Gaussian beams.

3. The device according to claim 1, characterized in that The beam combining module includes: a common aperture beam combining mirror, a high reflection beam splitting prism and a high transmission beam splitting prism. The high-reflection beam splitter prism is arranged behind the first light source module, and the high-transmission beam splitter prism is arranged behind the second light source module, so that the first laser and the second laser are respectively incident on the common-aperture beam combiner through different paths.

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

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

6. A method for optimizing the non-uniformity of light intensity distribution of a ZnSe lens, characterized in that: include: Determine the number and arrangement of laser units based on the parameters of the CO2 laser and the optical properties of the ZnSe lens to be irradiated; Constructing a device for optimizing the non-uniformity of light intensity distribution of a ZnSe lens as described in any one of claims 1 to 5, and adjusting the focal length of the zoom module so that the intensity of the sampling light on the ZnSe lens to be irradiated has a Gaussian distribution; A light-heat multi-physics field model is constructed, and based on the monitoring data of the first detection module and the second detection module in the irradiation state, the output power ratio and timing of the first light source module and the second light source module are optimized through a closed-loop control module.

7. The method according to claim 6, characterized in that The method of determining the number and arrangement of laser units according to the parameters of the CO2 laser and the optical properties of the ZnSe lens to be irradiated includes: Constructing an objective function based on the light intensity distribution after passing through the beam combining module, and optimizing the objective function based on constraints to minimize the light intensity error of the objective function; The objective function is solved using a Lagrange multiplier method or a 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: The constraints are: CO2 laser total power conservation Wavelength power allocation: ∑ MIR k i =m1,∑ NIR k i =m2, m1+m2=1; weight k i ≥0; Wherein, N is the number of the laser units; I i (r j ) indicates that the i-th subaperture is at position r j The light intensity at I target (r j ) represents the position r j The target light intensity at .

9. The method according to claim 6, characterized in that The construction of the light-heat multi-physics field model includes: The light intensity and temperature field are coupled by the finite element method, and the temperature field T(r) is taken as an additional constraint for light intensity optimization to establish the steady-state thermal equation of the ZnSe lens and obtain the temperature field T(r); The second laser power is dynamically adjusted according to the edge temperature measured in real time.

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 sampling light on the ZnSe lens to be irradiated is in a flat-top distribution or a multi-focus distribution.

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