Multi-laser optical path adaptive collimation control system and method with reflection protection

Abstract

The present invention provides a multi-laser optical path adaptive collimation control system and method with reflection protection, which relates to the field of plasma diagnostics and includes: adjusting the optical path system; the first image collector monitors and samples the sampling spot at the first sampling position; the second image collector monitors and samples the sampling spot at the second sampling position; the computer respectively identifies, records, and labels the shape features and position features of the sampling spots of the first image collector and the second image collector; a multi-spot matching algorithm is used to process the spot images collected in real time by the first image collector and the second image collector and perform feedback adjustment on the piezoelectric ceramic mirror mount module group. The present invention can, by combining the dual-image collector spot monitoring system, monitor the positions of multiple optical paths in real time, and precisely adjust the mirror angle through the multi-spot matching algorithm, so that the beam always remains collimated during multiple reflection processes.

Description

Technical Field

[0001] The present invention relates to the field of plasma diagnostics, and particularly to a multi-laser optical path adaptive collimation control system and method with reflection protection. Background Art

[0002] With the in-depth research of nuclear fusion tokamak devices, laser plasma diagnostic technologies have developed rapidly, including plasma temperature measurement, plasma density measurement, etc. To ensure accurate measurement and efficient operation, the stability, collimation, and efficient control system of the laser optical path become crucial. However, with the application of multi-laser optical paths, this requirement becomes more complex. The laser beams in a multi-laser optical path system often need to be transmitted between multiple reflecting surfaces and undergo multiple reflections. Such a complex optical path structure may lead to collimation problems of the light beam, affecting the measurement accuracy and the long-term stability of the equipment.

[0003] Currently, many existing technologies rely on traditional mechanical adjustment means to ensure the collimation of the optical path, but these methods cannot effectively cope with the optical path deviation of the laser beam in actual applications, especially in the case of multiple reflections, where the deviation of the optical path is prone to accumulate. These problems will affect the accuracy of experimental results. Therefore, how to achieve the adaptive collimation control of multi-laser optical paths has become an urgent technical problem to be solved. The existing patents (such as patent number CN113433711B) provide a method for automatically collimating the optical path of a two-dimensional mirror frame based on TwinCAT Vision, but this system is only applied to the adjustment of a single optical path and lacks the ability to comprehensively control multiple optical paths. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a multi-laser optical path adaptive collimation control system and method with reflection protection. By combining a double image collector spot monitoring system, the positions of multiple optical paths are monitored in real time, and the angles of the reflecting mirrors are precisely adjusted through a multi-spot matching algorithm, so that the light beam always remains collimated during multiple reflections.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A multi-laser optical path adaptive collimation control method with reflection protection, comprising:

[0007] S1. Adjust the optical path system; the first image collector monitors and samples the sampling spot at the first sampling position; the second image collector monitors and samples the sampling spot at the second sampling position; the computer respectively identifies, records, and labels the shape features and position features of the sampling spots of the first image collector and the second image collector.

[0008] S2. Adopt a multi-spot matching algorithm to process the spot images collected in real time by the first image collector and the second image collector and perform feedback adjustment on the piezoelectric ceramic mirror mount module group; the multi-spot matching algorithm takes the center of the image collector's target surface as the original coordinate point to establish a coordinate system, and the X-axis and Y-axis of this coordinate system are respectively set as the horizontal and vertical directions of the image collector's target surface. For spot feature extraction, calculate the centroid coordinates of each spot ( , ).

[0009] A multi-laser optical path adaptive collimation control system with reflection protection includes a laser, an optical path system, a computer, a piezoelectric ceramic mirror mount module group, and a polarization control system;

[0010] Among them, the laser is used to output linearly polarized laser;

[0011] The optical path system is used to transmit the laser optical path and collect the sampled spots of the relative positions of multiple optical paths and transmit them to the computer;

[0012] The computer is used to process the spot images collected in real time;

[0013] The piezoelectric ceramic mirror mount module group adjusts the optical path;

[0014] The polarization control system is used to modulate the laser polarization state within picoseconds.

[0015] The present invention has the following beneficial effects:

[0016] The present invention uses the image collector module to monitor the changes of multiple optical paths in real time and collect high-precision image information. By using multiple image collectors, the multi-optical path position information at multiple positions can be obtained simultaneously, so as to accurately monitor the offset of the spots, ensure that the system remains synchronized during the adjustment of multiple optical paths, and greatly improve the adjustment efficiency. The present invention uses a multi-spot matching algorithm to accurately identify multiple spots, calculate the position offset of each spot, execute the algorithm efficiently, and quickly correct the error to ensure the accurate adjustment of the optical path. The present invention uses the polarization control system to adjust the laser polarization state within an extremely short time (picosecond level). By modulating the laser polarization, high-precision control of the laser can be achieved on the optical path to prevent the reflected laser from damaging the laser. The present invention uses the piezoelectric ceramic mirror mount module group to accurately adjust the pitch angle and yaw angle of the mirror according to the correction control signal. Its micrometer-level adjustment ability can ensure the collimation accuracy of the light beam, and can cope with the minute changes during multiple reflection processes, perform collimation adjustment on multiple optical paths, and ensure that the light beam always maintains an accurate direction. Description of the Drawings

[0017] Figure 1Schematic diagram of the structure and working process of a multi-laser optical path adaptive collimation control system with reflection protection according to the present invention;

[0018] Figure 2 The real-time spot pattern collected by the first image collector at the first sampling position and the adjusted spot pattern;

[0019] Figure 3 The real-time spot pattern collected by the second image collector at the second sampling position and the adjusted spot pattern.

[0020] In the figure, the reference numerals are: first parallel flat plate 1, second parallel flat plate 2, first convex lens 3, second convex lens 4, first plane mirror 5, second plane mirror 6, third plane mirror 7, fourth plane mirror 8, first plano-concave mirror 9, second plano-concave mirror 10, first image collector 11, second image collector 12, first piezoelectric ceramic mirror mount module 13, second piezoelectric ceramic mirror mount module 14, polarizer 15, photodetector 16, high-voltage switch 17, Pockels cell 18. Detailed implementation manners

[0021] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. To achieve the above objectives, the present invention adopts the following technical solutions.

[0022] As Figure 1 shown, the present invention provides a multi-laser optical path adaptive collimation control system with reflection protection, including a laser, an optical path system, a computer, a piezoelectric ceramic mirror mount module group, and a polarization control system. The laser is used to output linearly polarized laser. The optical path system is used to transmit the laser optical path and collect the spot images of the relative positions of multiple optical paths and transmit them to the computer. The computer is used to process the real-time collected spot images. The piezoelectric ceramic mirror mount module group realizes the adjustment of the optical path. During the operation of the tokamak plasma, it can be used to correct the optical path deviation caused by factors such as device vibration. The polarization control system is used to modulate the laser polarization state within an extremely short time (picosecond level) to prevent the laser from being damaged after the return optical path enters the laser.

[0023] Preferably, the optical path system includes a first parallel flat plate 1, a second parallel flat plate 2, a first convex lens 3, a second convex lens 4, a first plane mirror 5, a second plane mirror 6, a third plane mirror 7, a fourth plane mirror 8, a first plano-concave mirror 9, a second plano-concave mirror 10, a first image collector 11, and a second image collector 12.

[0024] The piezoelectric ceramic mirror mount module group includes a first piezoelectric ceramic mirror mount module 13 and a second piezoelectric ceramic mirror mount module 14.

[0025] The second planar mirror 6 is installed in the first piezoelectric ceramic mirror mount module 13, and the third planar mirror 7 is installed in the second piezoelectric ceramic mirror mount module 14. The first parallel flat plate 1 and the first planar mirror 5 are used to sample the relative positions of multiple optical paths at the first sampling position and output them to the first image collector 11.

[0026] The second parallel flat plate 2 and the fourth planar mirror 8 are used to sample the relative positions of multiple optical paths at the second sampling position and output them to the second image collector 12.

[0027] The first convex lens 3 and the second convex lens 4 are used to reduce the spot size and output the reduced spots to the first image collector 11 and the second image collector 12 respectively.

[0028] The first image collector 11 is used to collect the spot images of multiple optical paths at the first sampling position and output them to the computer.

[0029] The second image collector 12 is used to collect the spot images of multiple optical paths at the second sampling position and output them to the computer.

[0030] The first plano-concave mirror 9 and the second plano-concave mirror 10 are used to reflect the laser output by the laser back and forth multiple times on the optical path to form a multiple optical path optical system and make the laser focus located within the plasma measurement area.

[0031] Preferably, the laser can be a Nd:YAG laser or a ruby laser.

[0032] Preferably, the first parallel flat plate 1 and the second parallel flat plate 2 can be optical glass or quartz glass without coating.

[0033] Preferably, the first convex lens 3 and the second convex lens 4 can be plano-convex lenses or biconvex lenses.

[0034] Preferably, the first planar mirror 5, the second planar mirror 6, the third planar mirror 7 and the fourth planar mirror 8 need to be coated with an anti-reflection film of the laser wavelength. Among them, the second planar mirror 6 and the third planar mirror 7 can be made of metal parts or glass parts.

[0035] Preferably, the first image collector 11 and the second image collector 12 can be image collectors such as CCD or CMOS, and the selection of the area array size should be determined according to the actual design of the optical path.

[0036] Preferably, the polarization control system includes a polarizer 15, a photodetector 16, a high-voltage switch 17, and a Pockels cell 18.

[0037] The polarizer 15 is placed at the Brewster angle to transmit the polarized laser parallel to the incident plane, i.e., P-light, and reflect the polarized laser perpendicular to the incident plane, i.e., S-light.

[0038] The photodetector 16 is used to receive the incident laser S-component optical signal reflected by the polarizer 15, convert it into a pulsed electrical signal, and output it to the high-voltage switch 17.

[0039] The high-voltage switch 17 is used to provide fast and high-precision voltage switching, provide a rapidly switched electric field for the Pockels cell 18, and enable the Pockels cell 18 to complete the control of the optical signal within picoseconds.

[0040] The Pockels cell 18 is used to modulate the polarization state of light and convert P-light into S-light.

[0041] The polarizer 15 is placed at the Brewster angle on the optical path to ensure that the P-light of the incident laser is transmitted while the S-light is reflected. When the polarizer 15 is working properly, the P-light is transmitted to the target area, and a very small part of the S-light component is reflected to the photodetector 16.

[0042] Secondly, the photodetector 16 converts the received optical signal into a pulsed electrical signal, outputs it to the high-voltage switch 17, and drives the operation of the high-voltage switch 17. The high-voltage switch 17 quickly provides high voltage according to the received trigger signal, activates the Pockels cell 18, and controls the working state of the Pockels cell 18.

[0043] Then, after the Pockels cell 18 is activated, it converts the incident laser P-light into S-light. After the pulsed electrical signal ends, the high-voltage switch stops applying the electric field, and the electric field of the Pockels cell 18 no longer persists. When the reflected optical path passes through the Pockels cell 18, the polarization state of the laser does not change and remains S-light. When it is incident on the polarizer, it is reflected by the polarizer 15 to the first plano-concave mirror 9. While the first plano-concave mirror 9 and the second plano-concave mirror 10 form a reciprocating reflection optical path, it prevents damage caused by the return optical path entering the laser.

[0044] Preferably, the photodetector 16 can be a high-speed response PIN photodiode or APD (avalanche photodiode). The duration of the pulsed electrical signal of the photodetector 16 should be in the picosecond-nanosecond range, so that the Pockels cell 18 is activated before the incident laser reaches the Pockels cell 18. After the laser passes through the Pockels cell 18, the pulsed electrical signal ends, and the high-voltage switch 17 stops applying the electric field. The electric field of the Pockels cell 18 no longer persists. When the reflected optical path passes through the Pockels cell 18, the polarization state of the laser no longer changes.

[0045] Preferably, the high-voltage switch 17 can be a solid-state high-voltage switch or a semiconductor switch (such as IGBT or SiC MOSFET), etc.

[0046] Preferably, the Pockels cell 18 can be a KTP Pockels cell, a BBO Pockels cell, etc.

[0047] The present invention also proposes a multi-laser optical path adaptive collimation control method with reflection protection, including the following steps:

[0048] S1. Adjust the optical path system; the first image collector 11 monitors and samples the sampling light spot at the first sampling position; the second image collector 12 monitors and samples the sampling light spot at the second sampling position; the computer respectively identifies, records, and labels the shape characteristics and position characteristics of the sampling light spots of the first image collector 11 and the second image collector 12; the light spots of the first image collector 11 are labeled 1.1 and 1.2, and the light spots of the second image collector 12 are labeled 2.1 and 2.2.

[0049] S2. The computer uses a multi-light spot matching algorithm to process the light spot images collected in real time by the first image collector 11 and the second image collector 12 and perform feedback adjustment on the piezoelectric ceramic mirror mount module group. The multi-light spot matching algorithm takes the center of the image collector target surface as the original coordinate point to establish a coordinate system. The X-axis and Y-axis of this coordinate system are respectively set as the horizontal and vertical directions of the image collector target surface. For light spot feature extraction, calculate the centroid coordinates of each light spot ( , ).

[0050] S1 specifically includes:

[0051] S1.1. When the linearly polarized laser output by the laser passes through the polarizer 15, the P light is transmitted to the Pockels cell 18, and a very small part of the S light component will be reflected to the photodetector 16. The photodetector 16 converts the received optical signal into a pulsed electrical signal and outputs it to the high-voltage switch 17 to drive the operation of the high-voltage switch 17. The high-voltage switch 17 quickly provides high voltage according to the received trigger signal to activate the Pockels cell 18.

[0052] S1.2. After the Pockels cell 18 is activated, the incident P light is converted into S light and transmitted to the first parallel flat plate 1. Subsequently, the S light is reflected by the second plane mirror 6 mounted on the first piezoelectric ceramic mirror mount module 13 to the third plane mirror 7 mounted on the second piezoelectric ceramic mirror mount module 14, and after being reflected by the third plane mirror 7, it is transmitted through the second parallel flat plate 2 and then reflected by the second plano-concave mirror 10.

[0053] S1.3. The light reflected by the second plano-concave mirror 10 then sequentially passes through the second parallel plate 2, the third plane mirror 7, the second plane mirror 6, the first parallel plate 1, and the Pockels cell 18, and finally is reflected by the polarizer 15 to the first plano-concave mirror 9. After being reflected by the first plano-concave mirror 9, the light beam reaches the polarizer 15 again, and is reflected and transmitted by the polarizer 15 to the Pockels cell 18. This process repeats, forming an optical path with multiple back-and-forth reflections in the optical path system between the first plano-concave mirror 9 and the second plano-concave mirror 10.

[0054] S1.4. At the first sampling position, in all the laser beams transmitted from the Pockels cell 18 to the first parallel plate 1, a very small part is reflected by the first parallel plate 1 to the first plane mirror 5. Subsequently, this part of the light is transmitted through the first parallel plate 1 after being reflected by the first plane mirror 5, and is focused by the first convex lens 3 to the first image collector 11, forming multiple sampling spots. At the same time, in all the laser beams reflected by the second plane mirror 6 to the first parallel plate 1, a very small part is also reflected by the first parallel plate 1 to the first convex lens 3, and is further focused by the first convex lens 3 to the first image collector 11, forming multiple sampling spots. The first image collector 11 monitors and collects data on these sampling spots.

[0055] S1.5. At the second sampling position, in all the laser beams transmitted from the second plano-concave mirror 10 to the second parallel plate 2, a part is reflected by the second parallel plate 2 to the fourth plane mirror 8. Subsequently, this part of the light is transmitted through the second parallel plate 2 after being reflected by the fourth plane mirror 8, and is focused by the second convex lens 4 to the second image collector 12, forming multiple sampling spots. At the same time, in all the laser beams reflected by the third plane mirror 7 to the second parallel plate 2, a very small part is also reflected by the second parallel plate 2 to the second convex lens 4, and is further focused by the second convex lens 4 to the second image collector 12, forming multiple sampling spots. The second image collector 12 monitors and collects data on these sampling spots.

[0056] Specifically, in S2, the multi-spot matching algorithm takes the center of the image collector's target surface as the original coordinate point to establish a coordinate system, and the X-axis and Y-axis of this coordinate system are respectively set as the horizontal and vertical directions of the image collector's target surface. For spot feature extraction, for the centroid coordinates ( , ) of each spot, the following formula can be used to calculate:

[0057] ;

[0058] ;

[0059] Among them, ( , ) is the intensity of each pixel in the image,( , ) is the position of the pixel,( , ) is the centroid coordinate of the light spot.

[0060] The multi-light spot matching algorithm assigns a unique label to each light spot by extracting the centroid coordinates and shape features of each light spot.

[0061] Calculate the offset between each light spot and the calibration position during real-time acquisition. The offset is represented by a vector. Assume that the calibration position is known ( , ) and the current acquisition position ( , ), then the offset can be calculated according to the following formula:

[0062] ;

[0063] ;

[0064] where, and are the offsets of the light spot on the X-axis and Y-axis respectively.

[0065] Combine the offsets of all light spots to determine the total offset that needs to be adjusted for the two piezoelectric ceramic mirror mount modules. Assume that there are n light spots at each sampling position, and the total offset at each sampling position can be calculated using the following formula:

[0066] ;

[0067] ;

[0068] where, j represents the jth sampling position, represents the weight of each light spot at the jth sampling position, , represent the X-offset and Y-offset of the ith light spot in the jth sampling position respectively, and represent the total offsets on the X-axis and Y-axis at the jth sampling position respectively; the offsets that need to be adjusted for the first piezoelectric ceramic mirror mount module 13 and the second piezoelectric ceramic mirror mount module 14 are obtained according to the following formula:

[0069] ;

[0070] ;

[0071] ;

[0072] ;

[0073] Wherein, ΔRX1 and ΔRX2 respectively represent the X-axis adjustment amounts of the first piezoelectric ceramic mirror mount module 13 and the second piezoelectric ceramic mirror mount module 14, ΔRY1 and ΔRY2 respectively represent the Y-axis adjustment amounts of the first piezoelectric ceramic mirror mount module 13 and the second piezoelectric ceramic mirror mount module 14, α and β are influence coefficients used to weight the influence of each sampling position on the adjustment of each mirror, and K1 and K2 are gain coefficients used to control the adjustment responses of the second and third planar mirrors 6 and 7. and respectively represent the total offsets on the X-axis and Y-axis at the first sampling position. and respectively represent the total offsets on the X-axis and Y-axis at the second sampling position.

[0074] Figure 2 are the real-time speckle pattern and the adjusted speckle pattern collected by the first image collector 11 at the first sampling position; where (a) is the real-time speckle pattern collected by the first image collector 11 at the first sampling position, (b) is the adjusted speckle pattern collected by the first image collector 11 at the first sampling position, and the speckle errors before and after adjustment are shown in Table 1.

[0075] Table 1

[0076]

[0077] Figure 3 are the real-time speckle pattern and the adjusted speckle pattern collected by the second image collector 12 at the second sampling position; where (a) is the real-time speckle pattern collected by the second image collector 12 at the second sampling position, (b) is the adjusted speckle pattern collected by the second image collector 12 at the second sampling position, and the speckle errors before and after adjustment are shown in Table 2.

[0078] Table 2

[0079]

[0080] The specific embodiments described above further elaborate on the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A multi-laser optical path adaptive collimation control method with reflection protection, characterized in that Including: S1. Adjust the optical path system; the first image collector monitors and samples the sampling light spot at the first sampling position; The second image collector monitors and samples the sampling light spot at the second sampling position; the computer respectively identifies, records, and labels the shape features and position features of the sampling light spots of the first image collector and the second image collector; S2. Adopt a multi-spot matching algorithm to process the spot images collected in real time by the first image collector and the second image collector and perform feedback adjustment on the piezoelectric ceramic mirror mount module group; the multi-spot matching algorithm takes the center of the image collector's target surface as the original coordinate point to establish a coordinate system, and the X-axis and Y-axis of this coordinate system are respectively set as the horizontal and vertical directions of the image collector's target surface. For spot feature extraction, calculate the centroid coordinates of each spot ( , ); Specifically, S1 includes: S1.

1. When the linearly polarized laser output by the laser passes through the polarizer, the P light is transmitted to the Pockels cell, and the S light is reflected to the photodetector. The photodetector converts the received optical signal into a pulsed electrical signal and outputs it to the high-voltage switch to drive the operation of the high-voltage switch. The high-voltage switch quickly provides high voltage according to the received trigger signal to activate the Pockels cell; After the Pockels cell is activated, the incident P light is converted into S light and transmitted to the first parallel flat plate; subsequently, the S light is reflected by the second plane mirror mounted on the first piezoelectric ceramic mirror mount module to the third plane mirror mounted on the second piezoelectric ceramic mirror mount module, and after being reflected by the third plane mirror, it passes through the first parallel flat plate and is then reflected by the second plano-concave mirror; The light reflected by the second plano-concave mirror then passes through the second parallel flat plate, the third plane mirror, the second plane mirror, the first parallel flat plate, and the Pockels cell in sequence, and finally is reflected by the polarizer to the first plano-concave mirror. The light beam reaches the polarizer after being reflected by the first plano-concave mirror, and after being reflected and transmitted by the polarizer to the Pockels cell, it reciprocates like this to form an optical path with multiple round-trip reflections between the first plano-concave mirror and the second plano-concave mirror; S1.

4. At the first sampling position, among all the laser beams transmitted from the Pockels cell to the first parallel flat plate, part of the light is reflected by the first parallel flat plate to the first plane mirror; subsequently, this part of the light passes through the first parallel flat plate after being reflected by the first plane mirror and is focused by the first convex lens to the first image collector to form multiple sampling light spots; at the same time, among all the laser beams reflected by the second plane mirror to the first parallel flat plate, part of the light is reflected by the first parallel flat plate to the first convex lens and further focused by the first convex lens to the first image collector to form multiple sampling light spots; the first image collector monitors and collects data on these sampling light spots; S1.

5. At the second sampling position, among all the laser beams transmitted from the second plano-concave mirror to the second parallel flat plate, part of the light is reflected by the second parallel flat plate to the fourth plane mirror; subsequently, this part of the light passes through the second parallel flat plate after being reflected by the fourth plane mirror and is focused by the second convex lens to the second image collector to form multiple sampling light spots; at the same time, among all the laser beams reflected by the third plane mirror to the second parallel flat plate, part of the light is also reflected by the second parallel flat plate to the second convex lens and further focused by the second convex lens to the second image collector to form multiple sampling light spots; the second image collector monitors and collects data on these sampling light spots.

2. The multi-laser optical path adaptive collimation control method with reflection protection according to claim 1, wherein The centroid coordinates of each light spot ( , ) are calculated using the following formula: ； ； Among them, ( , ) is the intensity of each pixel point in the image, ([[]] , ) is the position of the pixel point, ([[]] , ) is the centroid coordinate of the light spot; calculate the offset between each light spot and the calibration position during real-time acquisition. The offset is represented by a vector. Given the calibration position ([[]] , ) and the current acquisition position ([[]] , ), then the offset is calculated according to the following formula:​​​​ ； ； Among them, and are the offsets of the light spot on the X-axis and Y-axis respectively; the total offsets that need to be adjusted for the two piezoelectric ceramic mirror mount modules are determined by combining the offsets of all light spots; there are n light spots at each sampling position, and the total offset at each sampling position can be calculated by the following formula: ； ； where j represents the j-th sampling position, represents the weight of each light spot at the j-th sampling position, , respectively represent the X offset and Y offset of the i-th light spot in the j-th sampling position, and respectively represent the total offsets on the X-axis and Y-axis at the j-th sampling position; the offsets that need to be adjusted for the first piezoelectric ceramic mirror mount module and the second piezoelectric ceramic mirror mount module are obtained according to the following formula: ； ； ； ； where ΔRX1 and ΔRX2 represent the X-axis adjustment amounts of the first piezoelectric ceramic mirror mount module and the second piezoelectric ceramic mirror mount module respectively, ΔRY1 and ΔRY2 represent the Y-axis adjustment amounts of the first piezoelectric ceramic mirror mount module and the second piezoelectric ceramic mirror mount module respectively, α and β are influence coefficients used to weight the influence of each sampling position on the adjustment of the second plane mirror and the third plane mirror, and K1 and K2 are gain coefficients. and represent the total offsets on the X-axis and Y-axis at the first sampling position respectively. and represent the total offsets on the X-axis and Y-axis at the second sampling position respectively.

3. An adaptive collimation control system for a multi-laser optical path with reflection protection, which is used in the multi-laser optical path adaptive collimation control method with reflection protection according to any one of claims 1-2, is characterized in that, Including a laser, an optical path system, a computer, a piezoelectric ceramic mirror mount module group, and a polarization control system; Among them, the laser is used to output linearly polarized laser; The optical path system is used to transmit the laser optical path and collect the sampling spots of the relative positions of multiple optical paths and transmit them to a computer; The computer is used to process the spot images collected in real time; The piezoelectric ceramic mirror mount module group adjusts the optical path; The polarization control system is used to modulate the laser polarization state within picoseconds.

4. A multi-laser optical path adaptive collimation control system with reflection protection according to claim 3, characterized in that, The optical path system includes a first parallel flat plate, a second parallel flat plate, a first convex lens, a second convex lens, a first plane mirror, a second plane mirror, a third plane mirror, a fourth plane mirror, a first plano-concave mirror, a second plano-concave mirror, a first image collector, and a second image collector; Among them, the first parallel flat plate and the first plane mirror are used to sample the relative positions of multiple optical paths at the first sampling position and output them to the first image collector; The second parallel flat plate and the fourth plane mirror are used to sample the relative positions of multiple optical paths at the second sampling position and output them to the second image collector; The first convex lens and the second convex lens are used to reduce the spot size and output the reduced spots to the first image collector and the second image collector respectively; The first image collector is used to collect the spot images of multiple optical paths at the first sampling position and output them to the computer; The second image collector is used to collect the spot images of multiple optical paths at the second sampling position and output them to the computer; The second plane mirror and the third plane mirror are used to reflect the optical path, and the pitch angle and yaw angle of the second plane mirror and the third plane mirror can be adjusted; The first plano-concave mirror and the second plano-concave mirror are used to reflect the laser output by the laser back and forth multiple times on the optical path.

5. A multi-laser optical path adaptive collimation control system with reflection protection according to claim 3, characterized in that, The piezoelectric ceramic mirror mount module group includes a first piezoelectric ceramic mirror mount module and a second piezoelectric ceramic mirror mount module; The second plane mirror is installed in the first piezoelectric ceramic mirror mount module, and the third plane mirror is installed in the second piezoelectric ceramic mirror mount module. The pitch angle and yaw angle of the second plane mirror and the third plane mirror are adjusted through the first piezoelectric ceramic mirror mount module and the second piezoelectric ceramic mirror mount module.

6. The multi-laser optical path adaptive collimation control system with reflection protection according to claim 3, characterized in that, The polarization control system includes a polarizer, a photodetector, a high-voltage switch, and a Pockels cell; Among them, the polarizer is used to transmit the polarized laser parallel to the incident plane, that is, P light, and reflect the polarized laser perpendicular to the incident plane, that is, S light; The photodetector is used to receive the incident laser S light component signal reflected by the polarizer, convert it into a pulsed electrical signal, and output it to the high-voltage switch; The high-voltage switch is used to provide voltage switching, provide a rapidly switched electric field for the Pockels cell, and enable the Pockels cell to complete the control of the optical signal within picoseconds; The Pockels cell is used to modulate the polarization state of light and convert P light into S light.

7. A multi-laser optical path adaptive collimation control system with reflection protection according to claim 3, characterized in that, The laser is a Nd:YAG laser or a ruby laser.

8. The multi-laser optical path adaptive collimation control system with reflection protection according to claim 4, characterized in that The first parallel flat plate and the second parallel flat plate are optical glass or quartz glass and are not coated.

9. The multi-laser optical path adaptive collimation control system with reflection protection according to claim 4, wherein, The first convex lens and the second convex lens are plano-convex lenses or biconvex lenses.

10. A multi-laser optical path adaptive collimation control system with reflection protection according to claim 4, characterized in that, The first plane mirror, the second plane mirror, the third plane mirror, and the fourth plane mirror are coated with an anti-reflection film of the laser wavelength; among them, the second plane mirror and the third plane mirror are metal parts or glass parts.

11. The multi-laser optical path adaptive collimation control system with reflection protection according to claim 6, characterized in that, The photodetector is a PIN photodiode or an avalanche photodiode.

12. The multi-laser optical path adaptive collimation control system with reflection protection according to claim 6, wherein The high-voltage switch is a solid-state high-voltage switch or a semiconductor switch.

13. The multi-laser optical path adaptive collimation control system with reflection protection according to claim 6, wherein The Pockels cell is a KTP Pockels cell or a BBO Pockels cell.

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