CN112130337B - Fiber laser array piston phase and tilt phase synchronization control system and method - Google Patents

Abstract

The fiber laser array piston phase and tilt phase synchronization control system and method use a high-speed camera to detect the interference fringe image generated by the overlap of the reference light and the beam-reduced fiber laser array at the target surface of the high-speed camera and interfere, and the interference fringes The image is divided according to the sub-beams in the fiber laser array. According to the distribution of fringes in each sub-beam area, the piston phase error and tilt phase error of each unit beam are obtained, and then each phase modulator and each adaptive fiber are generated. The control signal of the collimator makes the tilt phase and piston phase of all sub-lasers be controlled to be consistent with the tilt phase and piston phase of the reference light respectively, and drives the corresponding phase modulator and adaptive fiber collimator to realize the tilt phase and piston phase. Synchronous control of the phase. The invention realizes the decoupling of the tilt phase error and the piston phase error from the optical level, and further improves the synthesis efficiency of the coherent synthesis.

Description

Fiber laser array piston phase and tilt phase synchronization control system and method

technical field

The invention relates to the technical field of fiber laser coherent synthesis, in particular to a phase control system and method for using a high-speed camera to perform real-time tilt and piston synchronization locking on a fiber laser array.

Background technique

Laser array coherent synthesis technology is one of the important methods to obtain high-power laser while maintaining high beam quality, and can be widely used in laser communication, phased array lidar and other fields.

The fiber laser coherent synthesis system is mostly realized by the main oscillator power amplification structure. The laser array comes from the same seed laser to ensure the coherence between the beams. However, because the laser arrays experience different optical paths, the piston phase between the sub-beams Very different. In addition, since the emitting devices between the sub-beams are independent of each other, the outgoing optical axes have tilt errors with each other. In the field of coherent synthesis, the piston phase and tilt phase errors of the laser array are the main factors that lead to the decline of the synthesis effect and the reduction of the brightness of the synthesis spot. Therefore, in the coherent synthesis system, a closed-loop control system should be used to correct the piston phase and the tilt phase in real time. , maintaining the beam quality of the composite beam.

FIG. 1 is a schematic structural diagram of a fiber laser array phase and tilt closed-loop control system previously adopted by the applicant. The system is designed based on the master oscillator power amplifier (English name is Master Oscillator Power Amplifier, MOPA for short), and consists of a seed fiber laser 101, a fiber beam splitter 102, a plurality of phase modulators 103, a plurality of It is composed of an adaptive fiber collimator 105 , a laser beam combiner 106 , a piston phase control system 107 , and a tilt phase control system 108 . The core idea of this system is to separate the tilt from the piston and close the loop to realize the correction of the piston phase and tilt phase errors. However, the system does not fundamentally remove the coupling relationship between the tilt phase and the piston phase. In the control strategy, the eigenfrequencies of the tilt phase noise and the piston phase noise are different, so that the control characteristics of the piston phase are not greatly affected during the control process. However, in a large-array fiber laser control system or a strong noise environment, the coupling effect between the two phase noises will affect the control effect of the phase control system, so the phase-locked system scheme shown in Figure 1 is not suitable for fiber lasers The array controls both the tilt of the laser array and the phase of the piston under strong noise conditions.

SUMMARY OF THE INVENTION

Aiming at the defects existing in the prior art, the present invention proposes a new fiber laser array piston phase and tilt phase synchronization control system and method. The invention realizes the synchronization control method of the fiber laser array tilt phase and the piston phase based on the high-speed camera. The invention realizes the decoupling of the tilt phase error and the piston phase error from the optical level, and completes the use of only one optical parameter detection device—high speed The camera completes the system design of synchronous high-frequency control of tilt phase error and piston phase error, which further improves the synthesis efficiency of coherent synthesis.

For realizing the above-mentioned technical purpose, the concrete technical scheme that the present invention adopts is as follows:

Fiber laser array piston phase and tilt phase synchronization control system, including seed laser, laser beam splitter, fiber phase modulator, laser amplifier, laser beam expander collimator, adaptive fiber collimator, beam splitter, sampling control unit;

The seed laser outputs the seed laser; the laser beam splitter is a 1×(N+1) array laser beam splitter, which divides the seed laser into N+1 sub-lasers, of which N sub-lasers are used for MOPA structure coherent synthesis output, and 1 sub-laser is used for output. used as reference light;

There are N fiber phase modulators, the N output ends of the N sub-lasers output by the laser beam splitter are respectively connected to a fiber phase modulator, and the N fiber phase modulators are respectively used to lock the piston phases of the N sub-lasers;

There are N+1 laser amplifiers, of which N laser amplifiers are connected to the output end of the fiber phase modulator to amplify the sub-lasers output by the fiber phase modulator; the output end of the laser beam splitter output reference light is connected to a laser amplifier, The reference light is amplified, and the amplified reference light is input to the laser beam expander collimator for beam expansion and collimation of the reference light, so that the size of the reference light matches the target surface size of the high-speed camera;

There are N adaptive fiber collimators, which are arranged in an array to form an adaptive fiber collimator array and output a fiber laser array; N laser amplifiers corresponding to the N beams of sub-lasers are connected to an adaptive fiber collimator respectively, The N adaptive fiber collimators are respectively used to lock the tilt phase of the N beams of sub-lasers output by the laser beam splitter;

The optical path of the fiber laser array is provided with a beam splitter, which reflects most of the power of the fiber laser array to the target, and uses a small part of the transmitted fiber laser array for the sampling control system; the sampling control unit includes a laser beam reducer, a high-speed Camera and image acquisition and phase control module, the reference light is input to the high-speed camera after passing through the laser beam expander and collimator, and the fiber laser array transmitted by the beam splitter is also incident to the high-speed camera, the fiber laser array and the reference beam after passing through the laser beam reducer. The light overlaps and interferes at the target surface of the high-speed camera. The high-speed camera captures the interference fringe image of the reference light and the fiber laser array; the phase control module collects and processes the interference fringe image information output by the high-speed camera to realize the tilt phase and the piston phase. synchronization control.

Specifically, the phase control module calculates the piston phase error between each sub-laser and the reference light at the high-speed camera according to the information of the interference fringe image, generates a control signal and outputs it to each phase modulator, and calculates the difference between each sub-laser and the reference light according to the information of the interference fringe image. The tilt phase error of the reference light is generated, and the control signal is generated and output to each adaptive fiber collimator, and the control signal of each phase modulator and each adaptive fiber collimator is generated, so that the tilt phase and piston phase of all sub-lasers are controlled to the respective Consistent with the tilt phase and piston phase of the reference beam.

Preferably, the laser beam reducer of the present invention includes a large-diameter long-focus aspheric aberration convex lens and a small-diameter short-focus aspheric aberration convex lens, the two lenses constitute a Kepler telescope system, and the beam reduction ratio is two lenses. The ratio of focal lengths is determined according to the ratio of the diameter of the circumscribed circle of the N adaptive fiber collimator arrays to the target surface size of the high-speed camera.

Preferably, the output power of the laser amplifier used for reference light amplification is adjustable, and the power density of the amplified reference light and the probe light of the fiber laser array is required to be comparable on the target surface of the high-speed camera, so as to generate an interference fringe image with high contrast. .

Preferably, the beam splitter is a high reflectivity beam splitter. After being split by the beam splitter, >99% of the laser energy is reflected and output, and <1% of the laser energy is transmitted and output to the sampling control system.

The invention provides a fiber laser array piston phase and tilt phase synchronization control method. In the fiber laser array piston phase and tilt phase synchronization control system, a high-speed camera is used to detect the reference light and the beam-reduced fiber laser array in the high-speed camera. The interference fringe image is generated after the target surface overlaps and interferes. The interference fringe image is divided into beams according to the sub-beams in the fiber laser array. According to the distribution of the fringes in each sub-beam area, the Piston phase error and tilt phase error for unit beams. The control signals of each phase modulator and each adaptive fiber collimator are generated according to the calculated piston phase error and tilt phase error of each unit beam, so that the tilt phase and piston phase of all sub-lasers are controlled to the tilt phase of the reference beam respectively. The phase of the piston is consistent, and the corresponding phase modulator and the adaptive fiber collimator are driven to realize the synchronous control of the tilt phase and the piston phase.

The present invention utilizes the high-speed camera to detect the interference spot light intensity distribution I _{interferometric} generated by the reference beam and the beam-reduced fiber laser array, separates the interference fringes according to the fiber laser array sub-beams, and separates the fringes of each sub-beam from the The distance and extremum position information are calculated, and the piston phase error and tilt phase error of each unit beam are calculated, and the calculated piston phase error and tilt phase error are closed-loop controlled by the control system, thus forming a fiber laser array. Synchronous control system for piston phase and tilt phase. The beneficial effects of the present invention are as follows:

The present invention combines the tilt phase calculation and the piston phase calculation system into one, and solves the problems of redundant control modules and complex working modes of the traditional phase control system.

The present invention adopts a one-step control system, which makes the control system highly integrated, and is convenient for transplantation and debugging in practical application.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained according to the structures shown in these drawings without creative efforts.

1 is a schematic structural diagram of a fiber laser array phase and tilt closed-loop control system adopted by the applicant before;

Fig. 2 is the optical path structure schematic diagram of the present invention;

FIG. 3 is a light spot shape in different states collected by a high-speed camera in an embodiment;

FIG. 4 is a diagram of the spot shape of the interference fringes of a unit beam collected by a high-speed camera in an embodiment, and a one-dimensional light intensity distribution diagram obtained by taking the center positions of the interference fringes spots along the x and y axes respectively.

Detailed ways

In order to make the technical solutions and advantages of the present invention clearer, 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, but not to limit the present invention.

Example 1:

2 , this embodiment provides a fiber laser array piston phase and tilt phase synchronization control system, including a seed laser 201 , a laser beam splitter 202 , a fiber phase modulator 203 , a laser amplifier 204 , and a laser beam expander collimator 205 , an adaptive fiber collimator 206, a laser beam combiner 207, a beam splitter 208, and a sampling control unit. The sampling control unit includes a laser beam reducer 209 , a high-speed camera 210 and an image acquisition and phase control module 211 . The number of fiber phase modulators 203 and adaptive fiber collimators 206 is N, and the number of laser beam expanding collimators 205 is one. The number of laser beam combiners 207 is one. There are N+1 laser amplifiers 204 . where N is an integer and N≥2.

The seed laser 201 is connected to the input of the laser beam splitter 202 . The laser beam splitter is a 1×(N+1) array laser beam splitter, and the laser beam splitter 202 has N+1 output ends. The seed laser output from the seed laser 201 is divided into N+1 sub-lasers by the laser beam splitter 202 , which are respectively output from the N+1 output ends of the laser beam splitter 202 . Among them, the N-channel sub-laser is used for the coherent synthesis output of the MOPA structure, and the 1-channel sub-laser is used as the reference light.

The ith output end of the laser beam splitter 202 is optically connected to the ith fiber phase modulator 203, i=1, . The output end of the i-th fiber phase modulator 203 is optically connected to the i-th laser amplifier 204 to amplify the sub-lasers output by the fiber phase modulator.

There are N adaptive fiber collimators 206, which are arranged in an array to form an adaptive fiber collimator array and output a fiber laser array. The output end of the ith laser amplifier 204 is connected to the optical path of the ith adaptive fiber collimator, and the N adaptive fiber collimators are respectively used to lock the tilt phase of the N beams of sub-lasers output by the laser beam splitter. The i-th adaptive fiber collimator 206 is used to collimate the laser output from the i-th laser amplifier 204 and provide a tilt phase correction function. The laser output from each adaptive fiber collimator 206 is linearly polarized laser, and the polarization direction same.

The N+1th output end of the laser beam splitter 202 outputs the reference light, and the N+1th output end of the laser beam splitter 202 is connected to the N+1th laser amplifier to amplify the reference light, and the amplified reference light is input The laser beam expander collimator 205 is used for beam expansion and collimation of the reference light, so that the size of the reference light matches the size of the target surface of the high-speed camera 210 .

A laser beam combiner 207 and a beam splitter 208 are arranged on the optical path of the fiber laser array output by the adaptive fiber collimator array. The laser beam combiner 207 outputs the input fiber laser array to the beam splitter with a high duty cycle optical path. The beam splitter 208 is a high reflectivity beam splitter. After being split by the beam splitter 208, >99% of the laser energy is reflected and output, and <1% of the laser energy is transmitted and output to the sampling control system.

The reference light is input to the high-speed camera 210 after passing through the laser beam expander and collimator 205 , and the fiber laser array transmitted through the beam splitter 208 is also incident to the high-speed camera 210 after passing through the laser beam reducer 209 . The laser beam reducer 209 reduces the spot radius of the input low-power fiber laser array and then outputs it to the target surface of the high-speed camera 210 .

The fiber laser array and the reference light overlap and interfere at the target surface of the high-speed camera 210 , and the high-speed camera 210 captures the interference fringe image of the reference light and the fiber laser array. The phase control module 211 collects the interference fringe image information output by the high-speed camera 210, and calculates the piston phase difference between the i-th sub-laser and the reference light at the high-speed camera and the tilt difference between the i-th sub-laser and the reference light according to the interference fringe image information, And generate a control signal and output it to the ith phase modulator to compensate the piston phase difference φ _i of the ith sub-laser, i=1,2,...,N; and generate a control signal and output it to the ith adaptive fiber collimator, Compensate the inclination difference μ _i and ν _i of the i-th sub-laser, i=1, 2, .

The laser beam reducer 209 includes a large-diameter long-focus aspheric aberration convex lens and a small-diameter short-focus aspheric aberration convex lens. The two lenses form a Kepler telescope system, and the beam reduction ratio is the ratio of the focal lengths of the two lenses. It is determined according to the ratio of the diameter of the circumscribed circle of the N adaptive fiber collimator arrays to the target surface size of the high-speed camera.

The output power of the laser amplifier 204 used for amplifying the reference light is adjustable, and the power density of the amplified reference light and the probe light of the fiber laser array on the target surface of the high-speed camera is required to be comparable to generate interference fringe images with high contrast.

The control method of the above-mentioned fiber laser array piston phase and tilt phase synchronization control system is as follows:

Step 1: Pass the seed laser through the laser beam splitter and take out one laser beam as a reference beam, which is used as a "ruler" for the inversion of the fiber laser array tilt phase error and piston phase error, and the remaining N beams of sub-lasers pass through the laser beam splitter. Independent amplification based on MOPA structure;

Step 2, after the N beams of sub-lasers pass through the adaptive fiber collimator array, a part of the sub-laser is reflected by a high-reflection mirror and acts on the target, and the other part of the transmitted light is used as a sampling beam for beam control;

Step 3, the sampling beam first passes through the beam reduction system, so that the size of the outgoing beam of the adaptive fiber collimator array is reduced to the size of the imaging target surface of the high-speed camera, and the position of the high-speed camera is adjusted so that the beam-reduced laser is vertically incident, and it is turned on at this time. A high-speed camera can capture the laser spot pattern shown in Figure 3(a);

Step 4: The reference light goes through the laser amplifier for power amplification, and then passes through the laser beam expander collimator with beam expander function for beam collimation, so that the size of the beam also matches the size of the target surface of the high-speed camera, and the reference light is turned on separately. , the laser spot pattern captured by the high-speed camera is shown in Figure 3(b);

Step 5: Turn on the reference light and the N-channel sub-lasers at the same time, and adjust the incident angle of the reference light incident on the high-speed camera until the interference fringe image shown in FIG. 3(c) appears;

Step 6, according to the interference fringe image collected by the high-speed camera, calculate the tilt phase and piston phase error between each sub-laser and the reference light in the fiber laser array, and calculate the tilt phase of all sub-lasers according to the "ruler" of the reference laser. , the piston phase is controlled to be consistent with the tilt phase of the reference laser and the piston phase, respectively. According to the transferability of the equal sign, each sub-laser can be controlled to output the same phase of the tilt and the piston respectively.

For a fiber laser array with a total diameter of emission surface D, the light field distribution on the emission surface is:

Among them, (x, y) are the coordinates of the emitting surface, N is the number of unit beams contained in the array, d is the clear diameter of the unit beam, (x _j , y _j ), φ _j , μ _j and ν _j are the th Center coordinates, piston phase, x-direction tilt phase, and y-direction tilt phase of the j unit beams.

After k times the spherical aberration-free laser beam reducer, the optical field distribution of the fiber laser array has the same form as formula (1), except that d in formula (1) is proportionally reduced to (x _j , y _j ), The conjugate light spot on the emission surface of the fiber laser array detected by the high-speed camera with proportionally amplified amplitude is shown in Figure 3(a), and its light field distribution is as follows:

After the reference light passes through the non-spherical aberration laser beam expander collimator, the high-speed camera detects the reference spot as shown in Figure 3(b), and its light field distribution is as follows:

Among them, (x, y) is the coordinates of the detection surface of the high-speed camera, w is the beam width of the reference light, and φ is the piston phase error of the reference light.

The reference light and the beam-reduced fiber laser array overlap and interfere at the target surface of the high-speed camera, and the resulting interference fringe image detected by the high-speed camera is shown in Figure 3(c). 2) Linear addition to equation (3):

According to the distribution of fringes in each unit beam area, the tilt phase and piston phase errors of the unit beam can be obtained.

Example 2:

This embodiment provides a fiber laser array piston phase and tilt phase synchronization control method. In the fiber laser array piston phase and tilt phase synchronization control system provided in Embodiment 1, a high-speed camera is used to detect the reference light and the beam-reduced fiber The interference fringe image is generated after the laser array overlaps and interferes at the target surface of the high-speed camera, and the interference fringe image is separated according to the neutron beam of the fiber laser array.

According to the distribution of fringes in each sub-beam area separated, the piston phase error and tilt phase error of each unit beam are obtained. Referring to FIG. 4 , FIG. 4( a ) is a light spot shape diagram of a unit beam interference fringe collected by a high-speed camera in an embodiment. The one-dimensional light intensity distribution is obtained at the center of the interference fringe spot in Fig. 4(a) along the x and y axes, respectively, as shown in Fig. 4(b) and Fig. 4(c). It can be deduced from equation (4) that the tilt phase error in the x-direction of the j-th unit beam can be calculated from the fringe spacing in the x-direction:

where δx _,j is the fringe spacing in the x direction of the interference fringe spot corresponding to the jth unit beam, k is the wave vector of the laser beam, _μref is the tilt phase of the reference beam in the x direction, μj is the _jth unit beam x Direction tilt phase.

Similarly, the y-direction tilt phase error of the jth unit beam can be calculated from the y-direction fringe spacing:

Among them, δ _y,j is the fringe spacing in the y direction of the interference fringe spot corresponding to the jth unit beam, and ν _ref is the tilt phase of the reference beam in the y direction.

According to the calculated x-direction tilt phase error and y-direction tilt phase error of the j-th unit beam, combined with the position coordinates of the extremum of the interference fringe, the piston phase error of the j-th unit beam can be calculated:

Among them, x _max is the maximum value coordinate of the stripe in the x direction, and y _max is the maximum value coordinate of the stripe in the y direction.

The control signals of each phase modulator and each adaptive fiber collimator are generated according to the calculated piston phase error and tilt phase error of each unit beam, so that the tilt phase and piston phase of all sub-lasers are controlled to the tilt phase of the reference beam respectively. The phase of the piston is consistent, and the corresponding phase modulator and the adaptive fiber collimator are driven to realize the synchronous control of the tilt phase and the piston phase.

In summary, although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person of ordinary skill in the art, without departing from the spirit and scope of the present invention, can make various modifications. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims (7)

1. a fiber laser array piston phase and tilt phase synchronization control method, it is characterized in that, comprise and build fiber laser array piston phase and tilt phase synchronization control system, described fiber laser array piston phase and tilt phase synchronization control system comprise seed laser , laser beam splitter, fiber phase modulator, laser amplifier, laser beam expander collimator, adaptive fiber collimator, beam splitter, sampling control unit, sampling control unit including laser beam reducer, high-speed camera and image acquisition and Phase control module; The seed laser outputs the seed laser; the laser beam splitter is a 1×(N+1) array laser beam splitter, which divides the seed laser into N+1 sub-lasers, of which N sub-lasers are used for MOPA structure coherent synthesis output, and 1 sub-laser is used for output. used as reference light; There are N fiber phase modulators, the N output ends of the N sub-lasers output by the laser beam splitter are respectively connected to a fiber phase modulator, and the N fiber phase modulators are respectively used to lock the piston phases of the N sub-lasers; There are N+1 laser amplifiers, of which N laser amplifiers are connected to the output end of the fiber phase modulator to amplify the sub-lasers output by the fiber phase modulator; the output end of the laser beam splitter output reference light is connected to a laser amplifier, The reference light is amplified, and the amplified reference light is input to the laser beam expander collimator for beam expansion and collimation of the reference light, so that the size of the reference light matches the target surface size of the high-speed camera; There are N adaptive fiber collimators, which are arranged in an array to form an adaptive fiber collimator array and output a fiber laser array; N laser amplifiers corresponding to the N beams of sub-lasers are connected to an adaptive fiber collimator respectively, The N adaptive fiber collimators are respectively used to lock the tilt phase of the N beams of sub-lasers output by the laser beam splitter; A beam splitter is arranged on the optical path of the fiber laser array, which reflects most of the power of the fiber laser array to the target, and uses a small part of the transmitted fiber laser array for the sampling control system; the reference light passes through the laser beam expander and collimator. Input to the high-speed camera, the fiber laser array transmitted by the beam splitter is also incident on the high-speed camera after passing through the laser beam reducer. The fiber laser array and the reference light overlap and interfere at the target surface of the high-speed camera, and the high-speed camera captures the reference light and the reference light. The interference fringe image of the fiber laser array; the phase control module collects and processes the information of the interference fringe image output by the high-speed camera; In the fiber laser array piston phase and tilt phase synchronization control system, the high-speed camera is used to detect the interference fringe image generated after the reference light and the beam-reduced fiber laser array overlap and interfere at the target surface of the high-speed camera. In the image, the interference fringes are separated according to the sub-beams of the fiber laser array. According to the distribution of the fringes in each sub-beam area separated, the piston phase error and tilt phase error of each unit beam are obtained; The piston phase error and tilt phase error of the fiber laser array generate the control signals of the phase modulator and the adaptive fiber collimator corresponding to each unit beam in the fiber laser array piston phase and tilt phase synchronization control system, so that the tilt phase of all sub-lasers, The piston phase is controlled to be consistent with the tilt phase and piston phase of the reference light, respectively, and the corresponding phase modulator and adaptive fiber collimator are driven to realize the synchronous control of the tilt phase and the piston phase. According to the distribution of the inner fringes, the method to obtain the piston phase error and tilt phase error of each unit beam is as follows: The one-dimensional light intensity distribution is obtained along the x and y axes at the center of the interference fringe spot in each sub-beam area. The x-direction tilt phase error of the jth unit beam can be calculated from the x-direction fringe spacing:

where δx _,j is the fringe spacing in the x direction of the interference fringe spot corresponding to the jth unit beam, k is the wave vector of the laser beam, _μref is the tilt phase of the reference beam in the x direction, μj is the _jth unit beam x direction tilt phase; The y-direction tilt phase error of the j-th unit beam can be calculated from the y-direction fringe spacing:

Among them, δ _y,j is the fringe spacing in the y direction of the interference fringe spot corresponding to the jth unit beam, and ν _ref is the tilt phase of the reference beam in the y direction; According to the calculated x-direction tilt phase error and y-direction tilt phase error of the j-th unit beam, combined with the position coordinates of the extremum of the interference fringe, the piston phase error of the j-th unit beam can be calculated:

Among them, x _max is the maximum value coordinate of the stripe in the x direction, and y _max is the maximum value coordinate of the stripe in the y direction. 2. The fiber laser array piston phase and tilt phase synchronization control method according to claim 1, characterized in that: the laser beam reducer comprises a large-diameter long-focus aspheric aberration convex lens and a small-diameter short-focus aspheric aberration convex lens , the Kepler telescope system is composed of two lenses, and the beam reduction ratio is the ratio of the focal lengths of the two lenses, which is determined according to the ratio of the diameter of the circumcircle of the N adaptive fiber collimator arrays to the target surface size of the high-speed camera. 3. fiber laser array piston phase and tilt phase synchronization control method according to claim 1, it is characterized in that: the output power of the laser amplifier used for reference light amplification is adjustable, and the reference light after amplification and the fiber laser array are required to be synchronously controlled. The power density of the probe light is comparable on the high-speed camera target surface to generate a high-contrast interference fringe image. 4. The fiber laser array piston phase and tilt phase synchronization control method according to claim 1, characterized in that: the beam splitter is a high reflectivity beam splitter, and after the beam splitter is split, >99% of the laser energy is reflected and output, <1% laser energy transmission output to the sampling control system. 5 . The fiber laser array piston phase and tilt phase synchronization control method according to claim 1 , 2 or 3 or 4 , wherein: N≧2. 6 . 6 . The fiber laser array piston phase and tilt phase synchronization control method according to claim 5 , wherein the laser output from each adaptive fiber collimator is linearly polarized laser with the same polarization direction. 7 . 7. The fiber laser array piston phase and tilt phase synchronization control method according to claim 5, characterized in that: further comprising a laser beam combiner, and the optical path of the fiber laser array output by the adaptive fiber collimator array is provided with a laser Beam combiner, laser beam combiner makes the input fiber laser array output to the beam splitter with a high duty cycle optical path.

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