A vacuum pulsed laser processing system and method for enhancing beam quality

Abstract

The present invention relates to the technical field of laser processing, and discloses a vacuum pulsed laser processing system and method for enhancing beam quality. The method includes: performing spatial filtering on the beam of pulsed laser in a vacuum environment by using a spatial filter; using a wavefront detection unit of a wavefront sensor to detect the wavefront information of the beam after spatial filtering in real time; obtaining the dynamic aperture size of the aperture in the spatial filter according to the wavefront information; determining whether the dynamic aperture size meets a preset standard, and if not, adjusting the aperture size and / or angle of the aperture until the dynamic aperture size meets the preset standard; wherein, the preset standard is that the dynamic aperture size should be within a preset range of minimum aperture size and maximum aperture size. Applying the present invention can achieve high-precision wavefront detection and automatic adjustment functions, realize efficient and reliable beam quality control, and is applicable to high-precision optical and laser technology applications.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and particularly to a vacuum pulsed laser processing system and method for enhancing beam quality. Background Art

[0002] In recent years, the improvement of beam quality has become particularly important in the field of laser technology, especially during the pulsed laser processing in a vacuum environment. However, there are still some problems in existing technical solutions in practical applications. For example, currently, beam quality improvement devices on the market usually adopt traditional mechanical or optical means, which have a slow response speed and are difficult to achieve precise control in the face of complex working conditions. This leads to problems such as low efficiency and inconvenient operation in some scenarios.

[0003] To improve performance, some manufacturers have tried to increase the automation level by adding advanced control algorithms. Such improvements often face problems such as high algorithm complexity and large consumption of computing resources, which increase the overall system cost and are difficult to maintain.

[0004] Chinese Patent with publication number CN110501826A discloses a method for improving beam quality based on phase carrier. By setting a reflective phase-type spatial light modulator in the optical path and loading a rectangular phase carrier with a suitable spatial frequency, the contradiction problem between the blocking hole size and the filtering size in the spatial filter is solved. Although this method can effectively improve the near-field beam quality, in a vacuum environment, its stability is poor and its adaptability to environmental changes is insufficient. In addition, this method relies on a high-precision spatial light modulator, which has a high cost and complex maintenance.

[0005] Chinese Patent with publication number CN114300939A discloses a high beam quality VCSEL structure and preparation method. By introducing a photonic crystal structure and an ion injection current suppression region into the VCSEL chip epitaxial structure, the laser beam quality is improved. This design performs well in improving beam quality, but in a vacuum environment, its structure complexity is high and the requirements for materials are relatively high. In addition, this method is difficult to achieve real-time monitoring and dynamic adjustment and cannot meet the application requirements in a high-dynamic environment.

[0006] The above problems indicate that traditional beam quality improvement devices on the market at present are difficult to effectively meet the new requirements for precise control and rapid response in pulsed laser processing in a vacuum environment. Summary of the Invention

[0007] The object of the present invention is to provide a vacuum pulsed laser processing system and method for enhancing beam quality, which realizes high-precision beam quality control based on the dynamic adjustment of the aperture size of the aperture in the spatial filter, meets the requirements of modern optics and laser technology for high stability and high resolution, and solves the problems of complex debugging, low system integration, limited resolution improvement and poor adaptability in the prior art in a vacuum environment.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] According to one aspect of the present invention, a vacuum pulsed laser processing method for enhancing beam quality is provided, including the following steps:

[0010] In a vacuum environment, spatial filtering is performed on the beam of the pulsed laser by using a spatial filter; the wavefront information of the beam after spatial filtering is detected in real time by the wavefront detection unit of the wavefront sensor; the dynamic aperture size of the aperture in the spatial filter is obtained according to the wavefront information; it is judged whether the dynamic aperture size meets a preset standard, and if not, the aperture size and / or angle of the aperture is adjusted until the dynamic aperture size meets the preset standard; wherein, the preset standard is that the dynamic aperture size should be within the range of a preset minimum aperture size and a maximum aperture size.

[0011] According to an embodiment of the present invention, the wavefront information includes slope data obtained by the wavefront detection unit detecting the beam after spatial filtering in real time.

[0012] According to an embodiment of the present invention, the detection accuracy of the wavefront detection unit is less than or equal to λ / 20, where λ is the wavelength of the pulsed laser.

[0013] According to an embodiment of the present invention, the wavefront information includes slope data obtained by the wavefront detection unit detecting the beam after spatial filtering in real time; the obtaining of the dynamic aperture size of the aperture in the spatial filter according to the wavefront information includes the following steps:

[0014] The Zernike coefficient vector is obtained from the slope data by using the least squares method; the high-order aberration is extracted from the Zernike coefficient vector; the high-order mode energy is obtained according to the high-order aberration; the dynamic aperture size of the aperture in the spatial filter is obtained based on the high-order mode energy.

[0015] According to an embodiment of the present invention, the obtaining of the high-order mode energy according to the high-order aberration is to perform cumulative summation after multiplying the square of each high-order aberration by the corresponding weight factor.

[0016] According to an embodiment of the present invention, the obtaining of the dynamic aperture size of the aperture in the spatial filter based on the high-order mode energy specifically includes:

[0017] Obtain the basic proportionality coefficient , referring to the laser power and the laser power at the current moment t , to obtain the proportionality coefficient which is

[0018] ;

[0019] Obtain the high-order mode energy and the saturation threshold , to obtain the energy response function which is

[0020] ;

[0021] Obtain the initial aperture size , and the dynamic aperture size obtained is

[0022] ;

[0023] wherein , where is the minimum aperture size, is the maximum aperture size, and the square of each high-order aberration is multiplied by the corresponding weight factor and then accumulated to obtain the high-order mode energy .

[0024] According to an embodiment of the present invention, the aperture stop is placed on the adjustment seat, and the aperture size of the aperture stop is adjusted by the aperture size adjustment motor installed on the adjustment seat, and the angle of the aperture stop is adjusted by the angle adjustment motor installed on the adjustment seat.

[0025] On the other hand, the present invention also provides a vacuum pulsed laser processing system for enhancing the beam quality, and the system includes:

[0026] A vacuum device 6 and a laser source 1, a spatial filter 2, a wavefront sensor 3, an automatic adjustment device 4, and a data processing unit 5 installed inside the vacuum device 6; the laser source 1 is connected to the spatial filter 2 through a collimating lens group 12, the wavefront sensor 3 is electrically connected to the data processing unit 5, and the automatic adjustment device 4 is electrically connected to the data processing unit 5 and installed on the spatial filter 2;

[0027] The spatial filter 2 includes an input collimator 21, an output collimator 22, an aperture stop 23, and an adjustment seat 24. The aperture stop 23 is installed between the input collimator 21 and the output collimator 22, and the adjustment seat 24 is installed on both sides of the aperture stop 23 for adjusting the aperture size and angle of the aperture stop 23; the aperture stop 23 performs spatial filtering on the pulsed laser beam emitted by the laser source 1;

[0028] The wavefront sensor 3 includes a wavefront detection unit 31 and a signal transmission unit 32. The wavefront detection unit 31 is used to detect the wavefront information of the laser beam, and the signal transmission unit 32 is used to transmit the detected wavefront information to the data processing unit 5;

[0029] The data processing unit 5 obtains the dynamic aperture size of the filtered aperture according to the wavefront information; determines whether the dynamic aperture size meets a preset standard. If it does not meet the standard, it controls the automatic adjustment device 4 to adjust the aperture size and / or angle of the aperture until the dynamic aperture size meets the preset standard; wherein, the preset standard is that the dynamic aperture size should be within a preset minimum aperture size and maximum aperture size range.

[0030] According to an embodiment of the present invention, the automatic adjustment device 4 includes an aperture size adjustment motor 41, an angle adjustment motor 42, an aperture size sensor 43, and an angle sensor 44. The aperture size adjustment motor 41 and the angle adjustment motor 42 are respectively installed on the adjustment seat 24; the aperture size of the aperture is adjusted by the aperture size adjustment motor installed on the adjustment seat, and the angle of the aperture is adjusted by the angle adjustment motor installed on the adjustment seat; the aperture size sensor 43 and the angle sensor 44 are respectively installed on both sides of the aperture 23 for real-time monitoring of the aperture size and angle of the aperture 23.

[0031] According to an embodiment of the present invention, the wavefront information includes slope data obtained by the wavefront detection unit in real-time detecting the beam after spatial filtering; the data processing unit 5 obtains the dynamic aperture size of the aperture after spatial filtering according to the wavefront information, including: obtaining the Zernike coefficient vector from the slope data by using the least squares method; extracting the high-order aberration from the Zernike coefficient vector; obtaining the high-order mode energy according to the high-order aberration; and obtaining the dynamic aperture size of the beam after spatial filtering based on the high-order mode energy.

[0032] Compared with the prior art, the beneficial effects produced by the present invention are as follows:

[0033] 1. High degree of automation. The automatic adjustment device can automatically adjust the aperture size and / or angle of the aperture when the wavefront information does not meet the preset standard, so that the beam quality is always in the best state, significantly improving the stability and reliability of the beam quality.

[0034] 2. High precision of beam quality. The high-precision wavefront detection unit and data processing unit can monitor and process the wavefront information in real-time, ensuring high-precision beam quality control in a vacuum environment and improving the intelligent level of the system.

[0035] 3. High integration level. The compact integrated design enables the entire system to have a high integration level and compactness in a vacuum environment, facilitating deployment and maintenance in a compact vacuum environment, and enhancing the adaptability and flexibility of the system. Description of the Drawings

[0036] The drawings described herein are used to provide a further understanding of the present invention, form a part of the present invention, and the schematic embodiments and descriptions thereof are used to explain the present invention without unduly limiting the present invention. In the drawings:

[0037] Figure 1 is a flowchart of the vacuum pulsed laser processing method for enhancing beam quality in an exemplary embodiment.

[0038] Figure 2 is a schematic diagram of the overall structure of the vacuum pulsed laser processing system for enhancing beam quality in an exemplary embodiment.

[0039] Figure 3 is a schematic diagram of the interior of a vacuum device in an exemplary embodiment.

[0040] Figure 4 is a schematic diagram of the structure of a laser source in an exemplary embodiment.

[0041] Figure 5 is of an exemplary embodiment Figure 3 An enlarged schematic diagram at position A.

[0042] Figure 6 is a schematic diagram of the structure of a wavefront sensor in an exemplary embodiment.

[0043] Figure 7 is a schematic diagram of the structure of a data processing unit in an exemplary embodiment.

[0044] Figure 8 is a schematic diagram of the structure of a vacuum device in an exemplary embodiment.

[0045] Figure 9 is a flowchart of the operation of the vacuum pulsed laser processing system for enhancing beam quality in an exemplary embodiment.

[0046] Reference Numerals:

[0047] 1 - Laser source; 11 - Pulse laser generator; 12 - Collimating lens group; 2 - Spatial filter; 21 - Input collimator; 22 - Output collimator; 23 - Aperture; 24 - Adjusting base; 3 - Wavefront sensor; 31 - Wavefront detection unit; 32 - Signal transmission unit; 4 - Automatic adjustment device; 41 - Aperture size adjustment motor; 42 - Angle adjustment motor; 43 - Aperture size sensor; 44 - Angle sensor; 5 - Data processing unit; 51 - Central processing unit; 52 - Data memory; 53 - Signal transceiver; A - Amplification area; 6 - Vacuum device; 61 - Vacuum chamber; 62 - Vacuum pump; 63 - Vacuum detector. Detailed implementation manners

[0048] For the convenience of clearly describing the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, terms such as "first" and "second" are used to distinguish identical or similar items with basically the same functions and effects. For example, the first threshold and the second threshold are only used to distinguish different thresholds, and do not limit their sequence. Those skilled in the art can understand that terms such as "first" and "second" do not limit the quantity and execution order, and "first", "second", etc. do not necessarily mean different.

[0049] It should be noted that in the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design solution described as "exemplary" or "for example" in the present invention should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific manner.

[0050] In the present invention, "at least one" means one or more, and "a plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone, where A and B may be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after. The following at least one (item) or its similar expression refers to any combination of these items, including any combination of single item (item) or plural items (items). For example, at least one (item) of a, b or c may represent: a, b, c, the combination of a and b, the combination of a and c, the combination of b and c, or the combination of a, b and c, where a, b, c may be single or multiple.

[0051] As Figure 1 shown, a flowchart of a vacuum pulse laser processing method for enhancing beam quality is given. The method includes the following steps:

[0052] Step S1: In a vacuum environment, spatially filter the beam of the pulsed laser using a spatial filter.

[0053] Step S2: Use the wavefront detection unit of the wavefront sensor to detect the wavefront information of the beam after spatial filtering in real time.

[0054] Step S3: Obtain the dynamic aperture size of the aperture in the spatial filter according to the wavefront information.

[0055] Step S4: Determine whether the dynamic aperture size meets the preset standard. If not, adjust the aperture size and / or angle of the aperture until the dynamic aperture size meets the preset standard. Among them, the preset standard is that the dynamic aperture size should be within the range of the preset minimum aperture size and the maximum aperture size.

[0056] Among them, the wavefront information includes the slope data obtained by the wavefront detection unit detecting the beam after spatial filtering in real time. The detection accuracy of the wavefront detection unit is less than or equal to λ / 20, where λ is the wavelength of the pulsed laser. Obtaining the dynamic aperture size of the aperture after spatial filtering according to the wavefront information includes the following steps:

[0057] Use the least squares method to obtain the Zernike coefficient vector from the slope data; extract the high-order aberration from the Zernike coefficient vector; obtain the high-order mode energy according to the high-order aberration; and obtain the dynamic aperture size of the aperture after spatial filtering based on the high-order mode energy.

[0058] Obtaining the high-order mode energy is obtained by multiplying the square of each high-order aberration by the corresponding weight factor and then performing cumulative summation. The obtaining of the dynamic aperture size of the beam after spatial filtering based on the high-order mode energy specifically includes: obtaining the basic proportionality coefficient , referring to the laser power and the laser power at the current time t , to obtain the proportionality coefficient as:

[0059] ;

[0060] Obtain the high-order mode energy and the saturation threshold , to obtain the energy response function as:

[0061] ;

[0062] Obtain the initial aperture size , to obtain the dynamic aperture size as:

[0063] ;

[0064] Among them, , where is the minimum aperture size, is the maximum aperture size.

[0065] The aperture stop is placed on the adjustment base, and the aperture size of the aperture stop is adjusted by a motor for adjusting the aperture size installed on the adjustment base, and the angle of the aperture stop is adjusted by a motor for adjusting the angle installed on the adjustment base.

[0066] As Figure 2 and Figure 3 shown, a vacuum pulsed laser processing system for enhancing beam quality based on a spatial filter includes a laser source 1, a spatial filter 2, a wavefront sensor 3, an automatic adjustment device 4, a data processing unit 5, and a vacuum device 6. The laser source, spatial filter, wavefront sensor, automatic adjustment device, and data processing unit are all installed in the vacuum device 6. The laser source is connected to the spatial filter through a collimating lens group. The wavefront sensor is electrically connected to the data processing unit, and the automatic adjustment device is electrically connected to the data processing unit and installed on the spatial filter.

[0067] As Figure 4 shown, the laser source 1 includes a pulsed laser generator 11 and a collimating lens group 12. The pulsed laser generator is used to generate pulsed laser, and the collimating lens group is used to collimate and transmit the pulsed laser to the spatial filter. The wavelength range of the pulsed laser generator is 1064 nm or 532 nm, the focal length of the collimating lens group is 100 mm, and the numerical aperture is less than or equal to 0.1.

[0068] For Figure 3 the A area shown, as Figure 5 shown, an enlarged schematic diagram of the A area is given. The spatial filter 2 includes an input collimator 21, an output collimator 22, an aperture stop 23, and an adjustment base 24. The aperture stop is installed between the input collimator and the output collimator, and the aperture stop 23 performs spatial filtering on the beam of the pulsed laser emitted by the laser source 1. The adjustment base is installed on both sides of the aperture stop and is used to adjust the aperture size and angle of the aperture stop. The mode field diameters of the input collimator and the output collimator are 6 μm and 8 μm respectively, and the aperture size adjustment range is 2 μm - 500 μm.

[0069] The automatic adjustment device 4 includes a position aperture size adjustment motor 41, an angle adjustment motor 42, an aperture size sensor 43, and an angle sensor 44. The aperture size adjustment motor and the angle adjustment motor are respectively installed on the adjustment seat. The aperture size sensor and the angle sensor are respectively installed on both sides of the aperture stop, and are used to monitor the size and angle of the aperture of the aperture stop in real time. The adjustment range of the aperture size adjustment motor is 2μm - 500μm, the resolution is less than 1μm, the maximum rotation angle of the angle adjustment motor is ±10°, and the resolution is less than 0.01°. The detection accuracy of the aperture size sensor is ±1μm, and the detection accuracy of the angle sensor is ±0.01°.

[0070] As Figure 6 shown, the wavefront sensor 3 includes a wavefront detection unit 31 and a signal transmission unit 32. The wavefront detection unit is used to detect the wavefront information of the laser beam, and the signal transmission unit is used to transmit the detected wavefront information to the data processing unit 5. The detection accuracy of the wavefront detection unit is less than or equal to λ / 20, where λ is the laser wavelength; the transmission rate of the signal transmission unit is greater than or equal to 100Mbps, and the transmission distance is greater than or equal to 100m.

[0071] As Figure 7 shown, the data processing unit 5 includes a central processor 51, a data memory 52, and a signal transceiver 53. The central processor is connected to the data memory through a data bus, and is used to store and process the data detected by the wavefront sensor, and judge the wavefront information according to a preset algorithm and logic and issue corresponding instructions; the signal transceiver is connected to the central processor and is used to receive and send instruction signals; the processing speed of the central processor is 3GHz, the capacity of the data memory is 128GB, and the transmission rate of the signal transceiver is 1Gbps.

[0072] The data processing unit 5 obtains the dynamic aperture size of the aperture stop in the spatial filter according to the wavefront information; judges whether the dynamic aperture size meets the preset standard, and if not, controls the automatic adjustment device 4 to adjust the aperture size and / or angle of the aperture stop until the dynamic aperture size meets the preset standard; wherein, the preset standard is: the dynamic aperture size should be within the preset minimum aperture size and maximum aperture size range.

[0073] The specific method for realizing the automatic adjustment of the dynamic aperture size of the light beam includes the following steps:

[0074] Step 501: Wavefront feature extraction; input the slope data obtained by the wavefront detection unit 31, and use the least squares method to obtain the Zernike coefficient vector from the slope data , where is the low-order aberration, is the high-order aberration;

[0075] Step 502: High-order mode energy evaluation: For high-order aberrations , high-order mode energy , where is a weighting factor, , is the radial order of the k-th Zernike term;

[0076] Step 503: Dynamic adjustment of aperture size. According to the high-order mode energy the dynamic aperture diameter can be obtained, where , and are the minimum and maximum sizes of the aperture respectively, is the initial aperture diameter, is the proportionality coefficient, , is the base proportionality coefficient, is the reference laser power, is the laser power; is the energy response function, , is the saturation threshold to avoid the aperture being too small when the high-order energy is extremely high.

[0077] As Figure 8 shown, the vacuum device 6 includes a vacuum chamber 61, a vacuum pump 62 and a vacuum detector 63. The vacuum chamber is used to accommodate the laser source 1, the spatial filter 2, the wavefront sensor 3, the automatic adjustment device 4 and the data processing unit 5. The vacuum pump 62 is used to evacuate the air, and the vacuum detector 63 is used to detect the vacuum degree. The evacuation rate of the vacuum pump 62 is 100 L / s, and the detection accuracy of the vacuum detector 63 is 10^-6 Pa.

[0078] As Figure 9 shown, the working process of the vacuum pulsed laser processing system for enhancing the beam quality includes the following steps:

[0079] a. The pulsed laser generated by the laser source 1 is collimated by the collimating lens group 12 and then transmitted to the spatial filter 2;

[0080] b. The diaphragm 23 performs spatial filtering on the beam to filter out the stray light and low-quality beams in the beam;

[0081] c. The filtered beam is transmitted to the wavefront sensor 3. The wavefront detection unit 31 detects the wavefront information of the beam in real time and transmits the detection data to the data processing unit 5 through the signal transmission unit 32;

[0082] d. The central processor 51 of the data processing unit 5 determines the wavefront information according to a preset algorithm and logic. When it detects that the wavefront information does not meet the preset standard, it sends an instruction to the automatic adjustment device 4 through the signal transceiver 53;

[0083] e. The aperture size adjustment motor 41 and the angle adjustment motor 42 adjust the aperture size and / or angle of the aperture 23 according to the instruction;

[0084] f. The aperture size sensor 43 monitors the aperture size of the aperture 23 in real time, and the angle sensor 44 monitors the angle of the aperture 23 in real time, and feeds the data back to the data processing unit 5;

[0085] g. The central processor 51 sends an instruction to the automatic adjustment device 4 through the signal transceiver 53 according to the feedback data, realizing the automatic adjustment of the aperture 23;

[0086] h. When the wavefront information meets the preset standard, the central processor 51 issues an instruction to stop the adjustment of the automatic adjustment device 4, completing the optimization of the beam quality.

[0087] In a specific embodiment, it is assumed that a pulsed laser with high stability and high beam quality is required in a high-precision optical experiment. The experimental environment is a vacuum environment, and the beam quality is required to reach the best state. First, install the laser source 1, the spatial filter 2, the wavefront sensor 3, the automatic adjustment device 4, and the data processing unit 5 in the vacuum device 6, and evacuate the vacuum chamber 61 to the required vacuum degree through the vacuum pump 62. Then start the pulsed laser generator 11 to generate pulsed laser, and collimate the laser through the collimating lens group 12 and transmit it to the spatial filter 2. The aperture 23 performs spatial filtering on the beam, removing stray light and low-quality beams. The filtered beam is transmitted to the wavefront sensor 3, and the wavefront detection unit 31 detects the wavefront information of the beam in real time, and transmits the detection data to the data processing unit 5 through the signal transmission unit 32. The central processor 51 determines the wavefront information according to a preset algorithm and logic. When it detects that the wavefront information does not meet the preset standard, it sends an instruction to the automatic adjustment device 4 through the signal transceiver 53. The aperture size adjustment motor 41 and the angle adjustment motor 42 adjust the aperture size and angle of the aperture 23 according to the instruction. The aperture size sensor 43 and the angle sensor 44 monitor the aperture size and angle of the aperture 23 in real time, and feed the data back to the data processing unit 5. The central processor 51 sends an instruction to the automatic adjustment device 4 through the signal transceiver 53 according to the feedback data, realizing the automatic adjustment of the aperture 23. When the wavefront information meets the preset standard, the central processor 51 issues an instruction to stop the adjustment of the automatic adjustment device 4, completing the optimization of the beam quality.

[0088] In the present invention, when the wavefront information does not meet the preset standard, the automatic adjustment device can automatically adjust the aperture size and / or angle of the diaphragm, so that the beam quality is always in the best state, significantly improving the stability and reliability of the beam quality. The high-precision wavefront detection unit and data processing unit can monitor and process the wavefront information in real time, ensuring high-precision beam quality control in a vacuum environment and improving the intelligent level of the system. The compact integrated design enables the entire system to have a high degree of integration and compactness in a vacuum environment, facilitating deployment and maintenance in a compact vacuum environment and improving the adaptability and flexibility of the system.

[0089] Although the present invention has been described in conjunction with various embodiments, however, in the process of implementing the claimed invention, those skilled in the art can understand and realize other variations of the disclosed embodiments by viewing the drawings, the disclosure content, and the like. In the specification, the word "comprising" does not exclude other components or steps, and "a" or "one" does not exclude the case of multiple. A single processor or other unit can implement several functions listed in the specification. Certain measures are recited in different embodiments, but this does not mean that these measures cannot be combined to produce good results.

[0090] Although the present invention has been described in conjunction with specific features and their embodiments, it is obvious that various modifications and combinations can be made without departing from the spirit and scope of the present invention. Accordingly, the present specification and the drawings are merely exemplary descriptions of the present invention and are considered to have covered any and all modifications, variations, combinations, or equivalents within the scope of the present invention. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the present invention and its equivalent technologies, the present invention also intends to include these changes and modifications.

Claims

1. A vacuum pulsed laser processing method for enhancing beam quality, characterized in that It includes the following steps: In a vacuum environment, spatially filter the beam of the pulsed laser using a spatial filter; Use the wavefront detection unit of the wavefront sensor to detect the wavefront information of the beam after spatial filtering in real time; Obtain the dynamic aperture size of the aperture in the spatial filter according to the wavefront information; Judge whether the dynamic aperture size meets the preset standard. If not, adjust the aperture size and / or angle of the aperture until the dynamic aperture size meets the preset standard; wherein, the preset standard is: the dynamic aperture size should be within the range of the preset minimum aperture size and maximum aperture size; The wavefront information includes slope data obtained by the wavefront detection unit detecting the beam after spatial filtering in real time; Obtaining the dynamic aperture size of the aperture in the spatial filter according to the wavefront information includes the following steps: Use the least squares method to obtain the Zernike coefficient vector from the slope data; Extract the high-order aberration from the Zernike coefficient vector; Obtain the high-order mode energy according to the high-order aberration; Based on the high-order mode energy, obtain the dynamic aperture size of the aperture in the spatial filter.

2. The method for processing a vacuum pulsed laser for enhancing beam quality according to claim 1, wherein The detection accuracy of the wavefront detection unit is less than or equal to λ / 20, where λ is the wavelength of the pulsed laser.

3. The method for processing a vacuum pulsed laser for enhancing beam quality according to claim 1, wherein Obtaining the high-order mode energy according to the high-order aberration is to perform cumulative summation after multiplying the square of each high-order aberration by the corresponding weight factor.

4. The method for processing a vacuum pulsed laser for enhancing beam quality according to claim 1, wherein The obtaining of the dynamic aperture size of the aperture in the spatial filter based on the high-order mode energy specifically includes: Obtain the basic proportionality coefficient , refer to the laser power and the laser power at the current moment t , and obtain the proportionality coefficient as follows: ； Obtain the high-order mode energy and the saturation threshold , and obtain the energy response function as follows: ； Obtain the initial aperture size , and obtain the dynamic aperture size which is ； Among them, , is the minimum aperture size, is the maximum aperture size. After multiplying the square of each high-order aberration by the corresponding weight factor and performing cumulative summation, the high-order mode energy is obtained .

5. The method for processing a vacuum pulsed laser for enhancing beam quality according to claim 1, wherein The aperture in the spatial filtering is placed on an adjustment seat, and the aperture size of the aperture is adjusted by an aperture size adjustment motor installed on the adjustment seat, and the angle of the aperture is adjusted by an angle adjustment motor installed on the adjustment seat.

6. A system for processing a vacuum pulsed laser for enhancing beam quality, wherein The system includes: a vacuum device (6) and a laser source (1), a spatial filter (2), a wavefront sensor (3), an automatic adjustment device (4), and a data processing unit (5) installed inside the vacuum device (6); the laser source (1) is connected to the spatial filter (2) through a collimating lens group (12), the wavefront sensor (3) is electrically connected to the data processing unit (5), and the automatic adjustment device (4) is electrically connected to the data processing unit (5) and installed on the spatial filter (2); The spatial filter (2) includes an input collimator (21), an output collimator (22), a diaphragm (23), and an adjustment base (24). The diaphragm (23) is installed between the input collimator (21) and the output collimator (22). The adjustment base (24) is installed on both sides of the diaphragm (23) and is used to adjust the aperture size and angle of the diaphragm (23). The diaphragm (23) performs spatial filtering on the beam of pulsed laser emitted by the laser source (1). The wavefront sensor (3) includes a wavefront detection unit (31) and a signal transmission unit (32). The wavefront detection unit (31) is used to detect the wavefront information of the laser beam, and the signal transmission unit (32) is used to transmit the detected wavefront information to the data processing unit (5). The data processing unit (5) obtains the dynamic aperture size of the diaphragm in the spatial filter according to the wavefront information; determines whether the dynamic aperture size meets the preset standard. If it does not meet the standard, it controls the automatic adjustment device (4) to adjust the aperture size and / or angle of the diaphragm until the dynamic aperture size meets the preset standard. Wherein, the preset standard is that the dynamic aperture size should be within the preset minimum aperture size and maximum aperture size range. The wavefront information includes slope data obtained by the wavefront detection unit detecting the beam after spatial filtering in real time. The data processing unit (5) obtains the dynamic aperture size of the diaphragm in the spatial filter according to the wavefront information, including: Obtaining the Zernike coefficient vector from the slope data by using the least squares method. Extracting the high-order aberration from the Zernike coefficient vector. Obtaining the high-order mode energy according to the high-order aberration. Obtaining the dynamic aperture size of the diaphragm in the spatial filter based on the high-order mode energy.

7. The vacuum pulsed laser processing system for enhancing beam quality according to claim 6, wherein The automatic adjustment device (4) includes an aperture size adjustment motor (41), an angle adjustment motor (42), an aperture size sensor (43), and an angle sensor (44). The aperture size adjustment motor (41) and the angle adjustment motor (42) are respectively installed on the adjustment base (24). Adjusting the aperture size of the diaphragm is achieved by the aperture size adjustment motor installed on the adjustment base, and adjusting the angle of the diaphragm is achieved by the angle adjustment motor installed on the adjustment base. The aperture size sensor (43) and the angle sensor (44) are respectively installed on both sides of the diaphragm (23) and are used to monitor the aperture size and angle of the diaphragm (23) in real time.

Images