Automatic axis calibration method and device for strong laser emission light path

Abstract

The invention relates to the technical field of intense laser, and discloses an automatic axis calibration method and device for an intense laser emission light path. The method comprises the steps that intense laser is guided into a laser collimator through an optical fiber to be collimated, and then the intense laser is transmitted to a spectroscope along a first vertical optical axis after being reflected by a fast reflecting mirror; the intense laser is divided into an output beam and a calibration beam through a spectroscope; and automatically controlling the reflection angle of the fast reflector by using the deviation between the calibration light beam and the second horizontal optical axis until the deviation is less than or equal to a deviation threshold value. According to the invention, on-line real-time axis calibration can be realized, and high-precision control of light beam pointing of an intense laser emission light path is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of laser emission optical paths, and particularly to an automatic optical axis alignment method and device for high-power laser emission optical paths. Background Art

[0002] A high-power laser emission system is a system capable of emitting laser beams with high power density or high energy, and is usually used in military, scientific research and other fields. High-energy lasers are used to generate high-energy laser beams. Common types of high-energy lasers include chemical lasers, solid-state lasers, fiber lasers, etc. The beam control system includes precise aiming and tracking systems for accurately controlling the direction of the laser beam to ensure that the laser beam can accurately irradiate the target. The system is usually equipped with components such as fast steering mirrors and tracking sensors, which can adjust the direction of the laser beam in real time to compensate for the movement of the target and atmospheric disturbances. The main function of the emission optical system is to expand and collimate the laser beam generated by the laser, so as to effectively transmit it to a distant target. The system usually consists of a series of optical elements such as lenses and mirrors.

[0003] The high-power laser emission system generates a high-energy laser beam through a high-energy laser, and then uses the beam control system and the emission optical system to accurately emit the laser beam to the target. In military applications, the high-power laser emission system can use the high energy density of the laser beam to destroy or blind targets such as airplanes, missiles, satellites, etc. For example, the Laser Weapon System Demonstrator (LWSD) in the United States can heat the target surface with a continuous-wave laser beam until the target melts. In addition, some advanced high-power laser emission systems also adopt coherent beam combination (CBC) technology or spectral beam combining technology to improve the power and quality of the laser beam.

[0004] High-precision pointing technology is inevitably involved in the high-power laser emission system. Since the high-power laser emission optical path generates heat, which causes deformation of the structural components and leads to deviation of the optical path pointing, affecting the laser emission accuracy and efficiency. The existing technology generally uses static optical path calibration, that is, adjusting the optical path on the collimator with a low-power laser, and it is impossible to perform online real-time optical axis alignment. Summary of the Invention

[0005] The purpose of the present invention is to provide an automatic optical axis alignment method and device for a high-power laser emission optical path, which can achieve online real-time optical axis alignment by setting a calibration optical path and a fast steering mirror, and improve the high-precision control of the beam pointing of the high-power laser emission optical path.

[0006] To achieve the above purpose, the present invention provides the following technical solutions: According to one aspect of the present invention, there is provided an automatic optical axis alignment method for a high-power laser emission optical path, including the following steps: Using an optical fiber to introduce the high-power laser into a laser collimator for collimation processing to be transmitted along a first horizontal optical axis; The high-power laser is reflected by a fast steering mirror disposed on the first horizontal optical axis and then transmitted along the first vertical optical axis to a beam splitter; The reflected beam reflected by the first surface of the beam splitter is transmitted along the first direction of the second horizontal optical axis to a first mirror, and after being reflected by the first mirror, it is transmitted along the second vertical optical axis as the output beam of the high-power laser emission optical path; The transmitted beam transmitted by the beam splitter is transmitted along the first vertical optical axis to a corner cube prism and then returns to the second surface of the beam splitter. After being reflected by the second surface, it is transmitted along the second direction of the second horizontal optical axis to a tracking detector as the calibration beam of the high-power laser emission optical path; The reflection angle of the fast steering mirror is automatically controlled by using the deviation between the calibration beam and the second horizontal optical axis until the deviation is less than or equal to a deviation threshold.

[0007] According to an embodiment of the present invention, the step of automatically controlling the reflection angle of the fast steering mirror by using the deviation between the calibration beam and the second horizontal optical axis until the deviation is less than or equal to a deviation threshold includes: Imaging the calibration beam by using a tracking detector; Determining the deviation value between the imaging spot of the calibration beam and the center of the detector by using a calibration controller; Generating an offset adjustment angle value according to the deviation value by using the calibration controller and sending it to the fast steering mirror; The fast steering mirror adjusts the reflection angle according to the offset adjustment angle value until the deviation value is less than or equal to the deviation threshold.

[0008] According to an embodiment of the present invention, the offset angle value includes an up-and-down offset angle value and / or a left-and-right offset angle value relative to the mirror surface of the fast steering mirror, and the fast steering mirror adjusts the reflection angle according to the up-and-down offset angle value and / or the left-and-right offset angle value.

[0009] According to an embodiment of the present invention, the transmittance of the beam splitter is less than or equal to 0.3%.

[0010] According to an embodiment of the present invention, the maximum response time of the fast steering mirror is less than or equal to 3.3 ms.

[0011] According to an embodiment of the present invention, the reflection surface of the fast steering mirror, the reflection surface of the mirror, and the first surface of the beam splitter need to withstand continuous laser impact with a power of 5000 W / cm 2 for 2 minutes and the temperature rise of the surface coating ≤ 10°C.

[0012] According to an embodiment of the present invention, the tracking detector is an imaging camera, or a photodetector in the wavelength band of 1050 nm to 1100 nm, or a photodetector in the wavelength band of 550 nm to 850 nm.

[0013] On the other hand, the present invention further provides a device for automatically aligning the optical path of a high-power laser emission, including: an emission optical path, a calibration optical path, and a calibration controller; the emission optical path includes an optical fiber, a laser collimator, a fast mirror, a beam splitter, and a reflector; the calibration optical path includes a beam splitter, a corner cube prism, and a tracking detector; The high-power laser is introduced into the laser collimator through the optical fiber and then transmitted along the first horizontal optical axis to the fast mirror, and after reflection, it is transmitted along the first vertical optical axis to the beam splitter; The reflected beam reflected from the first surface of the beam splitter is transmitted along the first direction of the second horizontal optical axis to the first reflector, and after being reflected by the first reflector, it is transmitted along the second vertical optical axis as the output beam of the high-power laser emission optical path; The transmitted beam transmitted through the beam splitter is transmitted along the first vertical optical axis to the corner cube prism and then returns to the second surface of the beam splitter. After being reflected by the second surface, it is transmitted along the second direction of the second horizontal optical axis to the tracking detector as the calibration beam of the high-power laser emission optical path; The calibration controller automatically controls the fast mirror to adjust the reflection angle until the deviation is less than or equal to the deviation threshold by using the deviation between the calibration beam and the second horizontal optical axis.

[0014] According to an embodiment of the present invention, the tracking detector images the calibration beam; The calibration controller determines the deviation value between the imaging spot of the calibration beam and the center of the detector, and generates an offset adjustment angle value according to the deviation value and sends it to the fast mirror; The fast mirror adjusts the reflection angle according to the offset adjustment angle value until the deviation value is less than or equal to the deviation threshold.

[0015] According to an embodiment of the present invention, the offset angle value includes an up-and-down offset angle value and / or a left-and-right offset angle value relative to the mirror surface of the fast mirror, and the fast mirror adjusts the reflection angle according to the up-and-down offset angle value and / or the left-and-right offset angle value; the maximum response time of the fast mirror is less than or equal to 3.3 ms.

[0016] The existing conventional methods cannot achieve thermal alignment of the axis, so it is also impossible to make the tracking axis and the emission axis have the same height. The solution of the present invention inserts a fast steering mirror into the high-power laser emission optical path and the precision tracking imaging optical path (i.e., the calibration optical path), and calculates the miss distance in real time based on the image information of the precision tracking camera to automatically control the fast steering mirror in a closed loop. The beam splitter and the optical corner cube prism combination sample the laser energy in the imaging optical path to obtain the real-time direction of the laser emission and provide correction information for the fast steering mirror.

[0017] Compared with the prior art, the beneficial effects produced by the present invention are as follows: 1. High real-time performance. Through the calibration optical path, the deviation value between the calibration beam and the horizontal optical axis can be detected online in real time, which indirectly reflects the deviation value of the high-power laser beam output by the emission optical path. At the same time, by controlling the fast steering mirror, real-time and rapid correction is performed according to the deviation; (Real-time detection and real-time rapid correction are achieved by entering the precision tracking through BS3 by 0.3%); 2. High correction accuracy. Due to the advantage of the optical path layout, the calibration optical path and the emission optical path are at the same height on the same optical axis, which can accurately reflect the beam deviation of the emission optical path. At the same time, by adopting an optimized automatic control adjustment algorithm, the correction accuracy is high; 3. Small energy loss. Under the action of the beam splitter, only 0.3% of the split light beam is required as the calibration beam, resulting in small energy loss of the high-power laser beam. Description of the Drawings

[0018] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 is a flowchart of a method for automatically aligning the axis of a high-power laser emission optical path according to an exemplary embodiment of the present invention.

[0019] Figure 2 is a schematic diagram of an automatic axis alignment device for a high-power laser emission optical path according to an exemplary embodiment of the present invention. Detailed Embodiments

[0020] In order to clearly describe 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 the same items 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 the terms "first" and "second" do not limit the quantity and execution order, and the terms "first" and "second" do not necessarily mean different.

[0021] It should be noted that in the present invention, words such as "exemplary" or "for example" are used to represent examples, illustrations or explanations. Any embodiment or design 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 designs. Rather, the use of words such as "exemplary" or "for example" is intended to present relevant concepts in a specific manner.

[0022] 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 there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone, where A and B can 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 can 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 and c can be single or multiple.

[0023] As Figure 1 shown, a flowchart of an automatic optical axis alignment method for a high-power laser emission optical path is given, and the method includes the following steps: Step S1: Use an optical fiber to introduce the high-power laser into a laser collimator for collimation processing to be transmitted along a first horizontal optical axis; Step S2: After the high-power laser is reflected by a fast steering mirror configured on the first horizontal optical axis, it is transmitted along a first vertical optical axis to a beam splitter; Step S3: The reflected beam reflected by the first surface of the beam splitter is transmitted along a first direction of a second horizontal optical axis to a first mirror, and after being reflected by the first mirror, it is transmitted along a second vertical optical axis as the output beam of the high-power laser emission optical path; Step S4: The transmitted beam transmitted through the beam splitter is transmitted along the first vertical optical axis to a corner cube prism and then returns to the second surface of the beam splitter. After being reflected by the second surface, it is transmitted along a second direction of the second horizontal optical axis to a tracking detector as the calibration beam of the high-power laser emission optical path; Step S5: Automatically control the reflection angle of the fast steering mirror using the deviation between the calibration beam and the second horizontal optical axis until the deviation is less than or equal to the deviation threshold.

[0024] The said step S5 includes: Step S51: Image the calibration beam using a tracking detector; Step S52: Use the calibration controller to determine the deviation value between the imaging spot of the calibration beam and the center of the detector; Step S53: Use the calibration controller to generate an offset adjustment angle value according to the deviation value and send it to the fast steering mirror; Step S54: The fast steering mirror adjusts the reflection angle according to the offset adjustment angle value until the deviation value is less than or equal to the deviation threshold.

[0025] The offset angle value includes the up-and-down offset angle value and / or the left-and-right offset angle value relative to the mirror surface of the fast steering mirror, and the fast steering mirror adjusts the reflection angle according to the up-and-down offset angle value and / or the left-and-right offset angle value. The maximum response time of the fast steering mirror is less than or equal to 3.3 ms. The transmittance of the beam splitter is less than or equal to 0.3%.

[0026] The reflection surface of the fast steering mirror, the reflection surface of the mirror, and the first surface of the beam splitter need to withstand a continuous laser impact of 5000 W / cm 2 for 2 minutes and the temperature rise of the surface coating ≤ 10 °C.

[0027] The tracking detector is an imaging camera, or a photodetector in the wavelength band of 1050 nm to 1100 nm, or a photodetector in the wavelength band of 550 nm to 850 nm.

[0028] The diameter of the high-power laser beam is 35 mm, and the light source power density is greater than or equal to 5000 W / cm².

[0029] As Figure 2 shown, the automatic alignment device for the high-power laser emission optical path implementing the alignment method includes: an emission optical path, a calibration optical path, and a calibration controller 26; the emission optical path includes an optical fiber 21, a laser collimator 22, a fast steering mirror 23, a beam splitter BS3, and a mirror M1; the calibration optical path includes a beam splitter BS3, a corner cube prism 24, and a tracking detector 25; The high-power laser is introduced into the laser collimator 22 through the optical fiber 21 and then transmitted along the first horizontal optical axis to the fast steering mirror 23, and after reflection, it is transmitted along the first vertical optical axis to the beam splitter BS3; The reflected beam reflected from the first surface of the beam splitter BS3 is transmitted along the first direction of the second horizontal optical axis to the first mirror M1, and after being reflected by the first mirror M1, it is transmitted along the second vertical optical axis as the output beam of the high-power laser emission optical path; The transmitted beam transmitted through the beam splitter BS3 is transmitted along the first vertical optical axis to the corner cube prism 24 and then returns to the second surface of the beam splitter BS3. After being reflected by the second surface, it is transmitted along the second direction of the second horizontal optical axis to the tracking detector 25 as the calibration beam of the high-power laser emission optical path; The calibration controller 26 automatically controls the fast steering mirror 23 to adjust the reflection angle by using the deviation between the calibration beam and the second horizontal optical axis until the deviation is less than or equal to the deviation threshold.

[0030] The tracking detector 25 images the calibration beam; the calibration controller 26 determines the deviation value between the imaging spot of the calibration beam and the center of the detector, generates an offset adjustment angle value according to the deviation value, and sends it to the fast steering mirror 23; the fast steering mirror adjusts the reflection angle according to the offset adjustment angle value until the deviation value is less than or equal to the deviation threshold.

[0031] The offset angle value includes the up-and-down offset angle value and / or the left-and-right offset angle value relative to the mirror surface of the fast steering mirror, and the fast steering mirror adjusts the reflection angle according to the up-and-down offset angle value and / or the left-and-right offset angle value; the maximum response time of the fast steering mirror is less than or equal to 3.3 ms.

[0032] The first surface of the beam splitter is coated with a beam splitting film. The beam splitting film has a reflectivity greater than 99.7% for light with a wavelength of 1050 nm to 1100 nm and a transmittance greater than 97.5% for light with a wavelength of 550 nm to 850 nm at an incident angle of 45° ± 2.5°; the surface profile quality RMS of the first surface of the beam splitter < λ / 40 (=632.8 nm); the second surface of the beam splitter is coated with a high anti-reflection hard film. The high anti-reflection hard film has a transmittance greater than 98.5% for light with a wavelength of 550 nm to 850 nm and light with a wavelength of 1050 nm to 1100 nm at an incident angle of 45° ± 2.5°. The beam splitter BS3 divides the laser into a reflected part and a transmitted part. 99.7% of the laser energy is directly reflected by the first surface of the BS3 mirror to the mirror M1 and then emitted; 0.3% of the laser energy is transmitted to the corner cube prism, returned by the corner cube prism to the second surface of the BS3 mirror, and reflected by the second surface into the imaging camera.

[0033] The reflection surface of the mirror is coated with a high reflection film. The high reflection film has a reflectivity greater than 99.7% for light with a wavelength of 1050 nm to 1100 nm and a reflectivity greater than 96.5% for light with a wavelength of 550 nm to 850 nm at an incident angle of 45° ± 2.5°; the surface profile quality RMS of the reflection surface of the mirror < λ / 40 (=632.8 nm). The mirror M1 selects an AO-level bubble-free and low-absorption optical glass material. The surface roughness of the optical glass material is less than or equal to 1 nanometer, and it undergoes annealing stress relief treatment and edge chamfering and deburring treatment.

[0034] The calibration beam and the output beam are on the same horizontal optical axis, so the deviation of the emission optical axis can be reflected. The calibration beam generates a laser spot in the imaging camera, which is mainly used for high-precision target tracking. When there is a deviation between the laser spot and the camera tracking center, it means that the emitted laser is inconsistent with the tracking position, and the optical axis needs to be calibrated.

[0035] For a beam transmitted along the horizontal optical axis, if there is a positional deviation between the imaging point of the beam on the camera imaging plane and the camera center point, the angle corresponding to this deviation can be determined through the following steps.

[0036] First, determine the relationship between the optical axis of the camera and the imaging plane. The internal parameters of the camera (such as focal length, principal point position, etc.) can be obtained through camera calibration. These parameters can convert the pixel coordinates on the image into actual physical coordinates. The optical axis of the camera is usually perpendicular to the imaging plane, but there may be installation angle errors in actual applications. If the camera is not installed horizontally, the actual direction of the optical axis can be determined through adjustment or calibration.

[0037] Then, measure the positional deviation between the imaging point and the center point. Process the image captured by the camera to extract the imaging point coordinates of the beam (such as detecting the center of the spot using image processing algorithms). Calculate the positional deviation between the imaging point and the camera center point (usually the geometric center of the image) in the image coordinate system to obtain the lateral and longitudinal pixel deviation values. Convert the positional deviation into an angular deviation.

[0038] Among them, using the camera focal length and the lateral positional deviation, calculate the lateral deviation angle through trigonometric functions θx =arctan( f Δ x ); θx is the lateral deviation angle, Δ x is the value after converting the lateral pixel deviation into the actual length, f is the focal length of the camera.

[0039] Similarly, the calculation formula for the longitudinal deviation angle is: θy =arctan( f Δ y ). Among them, θy is the longitudinal deviation angle, Δ y is the value after converting the longitudinal pixel deviation into the actual length.

[0040] Synthesize the lateral and longitudinal deviation angles vectorially to obtain the total deviation angle of the beam relative to the camera optical axis. According to the positive and negative of the lateral and longitudinal deviation angles, determine the direction of the deviation, that is, the deflection direction of the beam relative to the optical axis. Through the above steps, the angle corresponding to the positional deviation between the beam imaging point and the camera center point can be accurately determined, providing a basis for subsequent beam adjustment or system calibration.

[0041] The calibration controller calculates the coordinate deviation of the imaging spot of the calibration beam and the angle deviation of the tracking center, and controls the fast steering mirror to rotate in the opposite direction by the corresponding angle, so that the deviation between the imaging spot center of the calibration beam and the tracking center is less than the error range, that is, less than or equal to the deviation threshold, realizing online real-time fast alignment.

[0042] In the control system of the fast steering mirror, the calibration controller adopts the fuzzy adaptive PID control algorithm, which can dynamically adjust the PID parameters according to the real-time position error and error change rate of the fast steering mirror, so that the fast steering mirror can quickly and accurately track the direction change of the target beam. For example, when the beam needs to turn quickly, the fuzzy controller will appropriately increase the proportional gain Kp and the derivative gain Kd according to the current error and error change rate to accelerate the response speed of the mirror and suppress overshoot; when the error is small, Kp and Kd are appropriately reduced to avoid system oscillation and improve the stability of the system. In this way, the fuzzy adaptive PID control algorithm can significantly improve the response speed and control accuracy of the fast steering mirror, meeting the requirements of high-precision beam control.

[0043] The calibration controller can also improve the response speed of the fast steering mirror by using the zero-phase difference trajectory control method. First, it is necessary to establish a mathematical model of the fast steering mirror, and obtain the mathematical model as a transfer function or a state-space model through methods such as experimental identification and theoretical derivation. Then, analyze the characteristics such as the zero-pole distribution and frequency response of the system to determine the phase and amplitude characteristics of the system at different frequencies. After that, according to the characteristics of the system model and the reference signal, design a feedforward compensator so that the system can achieve zero-phase difference tracking of the reference input. The design of the feedforward compensator is usually based on the inverse model of the system or the phase compensation principle. Optimize the parameters of the feedforward compensator through optimization algorithms (such as the least squares method, genetic algorithm, etc.) to improve the tracking accuracy and response speed of the system. The response of the fast steering mirror is less than or equal to 3 ms. The bandwidth of the fast steering mirror is greater than 300 Hz, that is, the longest response time is 3.3 ms.

[0044] The calibration controller uses a PID controller or other advanced feedback control algorithms (such as adaptive control, sliding mode control, etc.) to implement a feedback controller. The feedforward compensator and the feedback controller are integrated into the calibration controller to form a closed-loop control system.

[0045] By eliminating the zeros and poles or phase differences of the controlled object, the phase delay of the system is reduced, thereby reducing the response time of the control system. The zero-phase difference trajectory control method can effectively suppress the overshoot of the system and improve the stability and control accuracy of the system. In the high-frequency band, the zero-phase difference control method can reduce the phase lag of the system and improve the high-frequency response ability of the system. The zero-phase difference trajectory control method can significantly improve the response speed and control performance of the fast steering mirror, meeting the requirements of high-precision beam control.

[0046] Existing conventional methods cannot achieve thermal alignment of the axis, so it is also impossible to make the tracking axis and the emission axis at the same height. The solution of the present invention inserts the fast steering mirror into the high-power laser emission optical path and the precision tracking imaging optical path (i.e., the calibration optical path), and calculates the miss distance in real time according to the image information of the precision tracking camera to automatically control the fast steering mirror in a closed loop. The beam splitter and the optical corner prism combination sample the laser energy in the imaging optical path to obtain the real-time direction of laser emission and provide correction information for the fast steering mirror.

[0047] Although the present invention has been described in connection 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 term "comprising" does not exclude other components or steps, and "a" or "one" does not exclude a plurality of situations. A single processor or other unit can implement several functions listed in the specification. Certain measures are described in different embodiments, but this does not mean that these measures cannot be combined to produce good results.

[0048] Although the present invention has been described in connection 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 cover 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. An automatic optical axis alignment method for a high-power laser emission optical path, characterized in that, Including the following steps: Using an optical fiber to introduce a high-power laser into a laser collimator for collimation processing to transmit along a first horizontal optical axis; The high-power laser is reflected by a fast steering mirror disposed on the first horizontal optical axis and then transmitted along a first vertical optical axis to a beam splitter; The reflected beam reflected by the first surface of the beam splitter is transmitted along a first direction of a second horizontal optical axis to a first mirror, and after being reflected by the first mirror, it is transmitted along a second vertical optical axis as the output beam of the high-power laser emission optical path; The transmitted beam transmitted through the beam splitter is transmitted along the first vertical optical axis to a corner cube prism and then returns to the second surface of the beam splitter. After being reflected by the second surface, it is transmitted along a second direction of the second horizontal optical axis to a tracking detector as the calibration beam of the high-power laser emission optical path; Automatically controlling the reflection angle of the fast steering mirror by using the deviation between the calibration beam and the second horizontal optical axis until the deviation is less than or equal to a deviation threshold; 2. The method for automatically aligning the optical axis of a high-power laser emission optical path according to claim 1, wherein The step of automatically controlling the reflection angle of the fast steering mirror by using the deviation between the calibration beam and the second horizontal optical axis until the deviation is less than or equal to a deviation threshold includes: Using a tracking detector to image the calibration beam; Using a calibration controller to determine the deviation value between the imaging spot of the calibration beam and the center of the detector; Using the calibration controller to generate an offset adjustment angle value according to the deviation value and send it to the fast steering mirror; The fast steering mirror adjusts the reflection angle according to the offset adjustment angle value until the deviation value is less than or equal to the deviation threshold; 3. The method for automatically aligning the optical axis of a high-power laser emission optical path according to claim 1, wherein The offset angle value includes an up-and-down offset angle value and / or a left-and-right offset angle value relative to the mirror surface of the fast steering mirror, and the fast steering mirror adjusts the reflection angle according to the up-and-down offset angle value and / or the left-and-right offset angle value; 4. The method for automatically aligning the optical axis of a high-power laser emission optical path according to claim 1, wherein The transmittance of the beam splitter is less than or equal to 0.3%; 5. The method for automatically aligning the optical axis of a high-power laser emission optical path according to claim 1, wherein The maximum response time of the fast steering mirror is less than or equal to 3.3 ms; 6. The method for automatically aligning the optical axis of a high-power laser emission optical path according to claim 1, wherein The reflective surface of the fast steering mirror, the reflective surface of the mirror, and the first surface of the beam splitter need to withstand continuous laser impact with a power of 5000 W / cm 2 for 2 minutes, and the temperature rise of the surface coating ≤ 10°C.

7. The method for automatically aligning the optical axis of a high-power laser emission optical path according to claim 1, wherein The tracking detector is an imaging camera, or a photodetector in the wavelength band of 1050 nm to 1100 nm, or a photodetector in the wavelength band of 550 nm to 850 nm; 8. An automatic optical axis alignment device for high-power laser emission, characterized in that, Including: An emission optical path, a calibration optical path and a calibration controller; the emission optical path includes an optical fiber, a laser collimator, a fast steering mirror, a beam splitter, and a mirror; the calibration optical path includes a beam splitter, a corner cube prism, and a tracking detector; The high-power laser is introduced into the laser collimator through the optical fiber and then transmitted along the first horizontal optical axis to the fast steering mirror, and after being reflected, it is transmitted along the first vertical optical axis to the beam splitter; The reflected light beam of the intense laser reflected by the first surface of the beam splitter is transmitted along the first direction of the second horizontal optical axis to the first reflector, and after being reflected by the first reflector, it is transmitted along the second vertical optical axis as the output light beam of the intense laser emission optical path; The transmitted light beam of the intense laser transmitted by the beam splitter is transmitted along the first vertical optical axis to the corner cube prism and then returns to the second surface of the beam splitter. After being reflected by the second surface, it is transmitted along the second direction of the second horizontal optical axis to the tracking detector as the calibration light beam of the intense laser emission optical path; The calibration controller automatically controls the fast reflector to adjust the reflection angle until the deviation is less than or equal to the deviation threshold by using the deviation between the calibration light beam and the second horizontal optical axis.

9. The automatic optical axis alignment device for the intense laser emission optical path according to claim 8, wherein The tracking detector images the calibration light beam; The calibration controller determines the deviation value between the imaging spot of the calibration light beam and the center of the detector, and generates an offset adjustment angle value according to the deviation value and sends it to the fast reflector; The fast reflector adjusts the reflection angle according to the offset adjustment angle value until the deviation value is less than or equal to the deviation threshold.

10. The automatic optical axis alignment device for the intense laser emission optical path according to claim 9, wherein The offset angle value includes the up-and-down offset angle value and / or the left-and-right offset angle value relative to the mirror surface of the fast reflector, and the fast reflector adjusts the reflection angle according to the up-and-down offset angle value and / or the left-and-right offset angle value; the maximum response time of the fast reflector is less than or equal to 3.3 ms.

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