A laser two-dimensional arbitrary multi-beam generation system and method

Abstract

The invention discloses a laser two-dimensional arbitrary multi-beam generation system, wherein the 90° prism vertex angles of two total reflection prisms are inward, the inclined surfaces are outward and parallel to each other; the semi-reflection prism includes two symmetrical semi-transparent and semi-reflective surfaces, and a bottom surface perpendicular to the inclined surface of the total reflection prism; the first total reflection prism anti-reflection surface and the first semi-transparent and semi-reflective surface are seamlessly bonded, and the second total reflection prism anti-reflection surface and the second semi-transparent and semi-reflective surface are seamlessly bonded; the two-dimensional spatial light modulator is located outside the bottom surface of the semi-reflection prism, and the analyzer is located outside the inclined surface of the second total reflection prism; the polarizer and the 1 / 4 wave plate are arranged in parallel between the two-dimensional spatial light modulator and the bottom surface of the semi-reflection prism; the 1 / 2 wave plate, the beam expander and the laser are arranged in sequence outside the inclined surface of the first total reflection prism. The invention adopts a partition control method to realize the joint modulation of the amplitude and phase of the laser near field, and can realize multi-beam formation and deflection based on any number, any independent angle, and any independent intensity distribution of a single spatial light modulator.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical phased array control and free space optical communication, and in particular relates to a laser two-dimensional arbitrary multi-beam generation system and method. Background Art

[0002] Laser communication systems urgently need multi-user communication capabilities, including point-to-multipoint and multi-point-to-multipoint communications. Traditional mechanical laser control systems have slow control speeds, low pointing accuracy, complex systems, and cannot achieve multi-beam access at any angle. Optical phased array (OPA) technology can not only achieve fast, agile and high-precision beam control, but also arbitrary beam shaping; secondly, optical phased array devices have the characteristics of small size, low power consumption, light weight, no rotational inertia and easy integration, which are very suitable for special platforms such as airborne, missile-borne and satellite-borne.

[0003] Radars equipped with excellent beam deflection devices can simultaneously transmit multiple beams and receive beams reflected by multiple moving targets, thereby achieving the ability to track and aim at multiple targets quickly. Flexible, arbitrary, and real-time multi-beam formation is the unique advantage of optical phased arrays. At present, star-to-star space laser communication, star-to-ground space laser communication, short-range atmospheric space laser communication, and quantum communication technology can only communicate point-to-point. Whether it is lidar and laser collimator, or laser-guided seeker and laser directed energy weapon, only one target can be locked at a time when working. Autonomous driving, laser communication networks, and new laser lidar systems have put forward unprecedented and urgent demands for multiple space laser beams, including arbitrary programmable control of beam two-dimensional angles, arbitrary programmable control of the number of beams, and link independence. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a laser two-dimensional arbitrary multi-beam generation system that adopts a partition control method to achieve joint modulation of laser near-field amplitude and phase, which can realize multi-beam forming and deflection based on any number, any independent angle, and any independent intensity distribution of a single spatial light modulator, and a method for generating laser two-dimensional arbitrary multi-beams using the system is provided.

[0005] The object of the present invention is achieved through the following technical solutions: a laser two-dimensional arbitrary multi-beam generation system, comprising a laser, a beam expander, a 1 / 2 wave plate, a first total reflection prism, a second total reflection prism, a semi-reflection prism, a polarizer, a two-dimensional spatial light modulator, a 1 / 4 wave plate and an analyzer;

[0006] In the spatial structure, the 90° prism vertex angles of the first total reflection prism and the second total reflection prism face inward, the first total reflection prism oblique surface and the second total reflection prism oblique surface face outward and are parallel to each other; the semi-reflection prism comprises two symmetrical semi-transparent and semi-reflective surfaces, and a semi-reflective prism bottom surface perpendicular to the first total reflection prism oblique surface and the second total reflection prism oblique surface; the first total reflection prism anti-reflection surface and the first semi-transparent and semi-reflective surface of the semi-reflection prism are seamlessly bonded, and the second total reflection prism anti-reflection surface and the second semi-transparent and semi-reflective surface of the semi-reflection prism are seamlessly bonded; the cross-section of the structure formed by the first total reflection prism, the second total reflection prism and the semi-reflective prism bottom surface is in the shape of a "district";

[0007] The two-dimensional spatial light modulator is located outside the bottom surface of the semi-reflective prism, and the polarizer is located outside the inclined surface of the second total reflection prism; the polarizer and the 1 / 4 wave plate are arranged in parallel between the two-dimensional spatial light modulator and the bottom surface of the semi-reflective prism; the 1 / 2 wave plate, the beam expander and the laser are arranged in sequence outside the inclined surface of the first total reflection prism.

[0008] Furthermore, the two-dimensional spatial light modulator is spatially divided into two regions: sub-region 1 cooperates with the polarizer for phase modulation; sub-region 2 and the 1 / 4 wave plate form a reflective polarization rotator, combined with the analyzer, to achieve amplitude modulation;

[0009] The thin light beam output by the laser forms a wide-diameter plane wave coarse light beam after passing through a beam expander. The coarse light beam enters a first total reflection prism after passing through a 1 / 2 wave plate, and after being totally reflected by a reflection surface of the first total reflection prism, enters a semi-reflection prism, and after passing through a polarizer, becomes linearly polarized light in a target polarization direction, and then is modulated and reflected by a working medium of sub-area 1 of a two-dimensional spatial light modulator; after entering the semi-reflection prism, the reflected light passes through a 1 / 4 wave plate after two reflections, and is modulated and reflected by a working medium of sub-area 2 of the two-dimensional spatial light modulator; the twice-modulated reflected light passes through a 1 / 4 wave plate, a reflection surface of a second total reflection prism, and a polarizer in sequence, and then is emitted.

[0010] The polarization directions of the polarizer and the analyzer are parallel; the reflection surface of the first total reflection prism is a metal-coated total reflection surface, and the first total reflection prism anti-reflection surface and the first total reflection prism inclined surface are multi-layer coated anti-reflection surfaces;

[0011] The first semi-transparent semi-reflective surface and the second semi-transparent semi-reflective surface of the semi-reflective prism are polarization-maintaining semi-transparent semi-reflective surfaces, and the bottom surface of the semi-reflective prism is a multi-layer coated anti-reflective surface;

[0012] The reflecting surface of the second total reflection prism is a metal-coated total reflection surface, and the anti-reflection surface of the second total reflection prism and the inclined surface of the second total reflection prism are multi-layer-coated anti-reflection surfaces.

[0013] The semi-reflective prism includes a semi-reflective corner cube prism or a semi-reflective Dove prism.

[0014] Another object of the present invention is to provide a method for generating two-dimensional arbitrary multi-beam laser beams, which is implemented by using the two-dimensional arbitrary multi-beam laser beam generation system of the present invention, and the specific steps are as follows:

[0015] The specific steps are as follows:

[0016] Step 1, build the system and calibrate: build a laser two-dimensional arbitrary multi-beam generation system according to the optical path, load specific modulation information to the two-dimensional spatial light modulator, move its position laterally and adjust the azimuth angle and pitch angle, observe the light field distribution characteristics of the outgoing light, when a sharp black cross appears in the near-field distribution, the amplitude and phase modulation pixels have been accurately aligned in space, and the spatial position and state of the two-dimensional spatial light modulator are locked;

[0017] Step 2: Set the target beam angle and power coefficient: Set the number of target beams n, the two-dimensional deflection angle θ of each beam xy (1),θ xy (2),…,θ xy (n) and the corresponding power coefficients a1, a2, ..., a n , where (x, y) is the far-field two-dimensional space coordinate;

[0018] Step 3: Calculate the two-dimensional phase modulation of the target angle beam: The phase used to generate the nth beam at the near-field two-dimensional spatial coordinate (x′, y′) is:

[0019]

[0020] Where k0 is the spatial frequency of the beam, θ x (n) and θ y (n) are the two-dimensional space angles θ xy (n) Angles in the x′ and y′ directions respectively;

[0021] Near field E at coordinate (x′, y′) near (x′y′), total phase φ(x′y′), and amplitude A(x′y′) are:

[0022]

[0023] Among them, MAX is The maximum value of and They represent the phase modulation required for the near-field coordinate point (x′, y′) corresponding to the ξth, ηth and mth beams in space respectively;

[0024] Step 4: Load the phase modulation signal: According to the spatial light modulator phase-voltage mapping table, find the A of the near-field coordinate point (x′y′) (x′y′)The voltage values ​​corresponding to φ(x′y′) are obtained, and the voltage matrices of sub-area 1 and sub-area 2 of the two-dimensional spatial light modulator are generated, which are finally merged into a complete voltage bitmap, which is loaded into the two-dimensional spatial light modulator to realize two-dimensional arbitrary multi-beam agile pointing and power allocation.

[0025] The beneficial effects of the present invention are:

[0026] 1. The laser two-dimensional arbitrary multi-beam generation system of the present invention is based on a spatial light modulator and adopts a partition control method to realize the joint modulation of the amplitude and phase of the laser near field. The optical path design structure is simple, and it can realize multi-beam formation and deflection based on any number, any independent angle, and any independent intensity distribution of a single spatial light modulator. This method is applicable to the two-dimensional arbitrary multi-beam generation of laser spatial light modulators, metasurface modulators, waveguide modulators and microwave phased arrays of other systems.

[0027] 2. The pixel alignment steps of the present invention are simple, ensuring the precise alignment and matching of the amplitude and phase of the entire pixel column; based on the spatial light modulator, a new variable coefficient amplitude-phase co-modulation special algorithm is adopted to achieve agile two-dimensional arbitrary multi-beam generation capability, which can meet the needs of multi-target tracking and aiming of new-system laser radars. Its two-dimensional multi-beam generation capability of any number, angle and power provides theoretical feasibility support and technical guarantee for the realization of free-space laser communication networking. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the structure of the laser two-dimensional arbitrary multi-beam generating system of the present invention;

[0029] Figure 2 It is a flow chart of the method for generating arbitrary two-dimensional multi-beams of laser according to the present invention;

[0030] Figure 3 : This is the near field distribution diagram before and after the system calibration of this embodiment;

[0031] Figure 4 Generate an amplitude-phase co-modulation bitmap of the far-field beam "Tai Chi diagram" distribution for this embodiment;

[0032] Figure 5 This is a simulation effect diagram of the “Tai Chi diagram” distribution of the far-field light beam in this embodiment;

[0033] Figure 6 This is an experimental test diagram of the far-field light beam “Tai Chi diagram” distribution of this embodiment;

[0034] Explanation of the accompanying drawings: 1: laser; 2: beam expander; 3: 1 / 2 wave plate; 4: first total reflection prism; 4-1: reflecting surface of the first total reflection prism, 4-2: anti-reflection surface of the first total reflection prism; 4-3: inclined surface of the first total reflection prism; 5-semi-reflecting prism; 5-1: first semi-transparent and semi-reflective surface; 5-2: second semi-transparent and semi-reflective surface; 5-3: bottom surface of the semi-reflecting prism; 6-polarizer; 7-two-dimensional spatial light modulator; 8-1 / 4 wave plate; 9: second total reflection prism; 9-1: reflecting surface of the second total reflection prism; 9-2: anti-reflection surface of the second total reflection prism; 9-3: inclined surface of the second total reflection prism; 10: analyzer. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0036] like Figure 1 As shown, a laser two-dimensional arbitrary multi-beam generating system of the present invention comprises a laser 1, a beam expander 2, a half wave plate (HWP) 3, a first total reflection prism 4, a second total reflection prism 9, a semi-reflecting prism 5, a polarizer 6, a two-dimensional spatial light modulator (SLM) 7, a quarter wave plate (QWP) 8 and an analyzer 10;

[0037] In the spatial structure, the 90° prism vertex angles of the first total reflection prism 4 and the second total reflection prism 9 are inward, and the first total reflection prism bevel 4-3 and the second total reflection prism bevel 9-3 are outward and parallel to each other; the semi-reflection prism 5 includes two symmetrical semi-transparent and semi-reflective surfaces, and a semi-reflective prism bottom surface 5-3 that is perpendicular to the first total reflection prism bevel 4-3 and the second total reflection prism bevel 9-3; the first total reflection prism anti-reflection surface 4-2 and the first semi-transparent and semi-reflective surface 5-1 of the semi-reflection prism 5 are seamlessly bonded, and the second total reflection prism anti-reflection surface 9-2 and the second semi-transparent and semi-reflective surface 5-2 of the semi-reflection prism 5 are seamlessly bonded; the cross-section of the structure formed by the first total reflection prism 4, the second total reflection prism 9 and the semi-reflection prism bottom surface 5-3 is in the shape of a "district"; the first total reflection prism reflection surface 4-1 and the second total reflection prism reflection surface 9-1 are right-angle surfaces on the first total reflection prism 4 and the second total reflection prism 4 that are not adjacent to the semi-reflection prism 5 respectively;

[0038] The two-dimensional spatial light modulator 7 is located outside the bottom surface 5-3 of the semi-reflective prism, and the polarizer 10 is located outside the inclined surface 9-3 of the second total reflection prism; the polarizer 6 and the 1 / 4 wave plate 8 are arranged in parallel between the two-dimensional spatial light modulator 7 and the bottom surface 5-3 of the semi-reflective prism; the 1 / 2 wave plate 3, the beam expander 2 and the laser 1 are arranged in sequence outside the inclined surface 4-3 of the first total reflection prism.

[0039] The two-dimensional spatial light modulator 7 is spatially divided into two regions: sub-region 1 cooperates with the polarizer 6 for phase modulation; sub-region 2 and the 1 / 4 wave plate 8 form a reflective polarization rotator (PRP), combined with the analyzer 10, to achieve amplitude modulation;

[0040] The fine light beam output by the laser 1 forms a wide-diameter plane wave coarse light beam after passing through the beam expander 2. The coarse light beam enters the first total reflection prism 4 after passing through the 1 / 2 wave plate 3, and enters the semi-reflecting prism 5 after being totally reflected by the reflection surface 4-1 of the first total reflection prism. After passing through the polarizer 6, it becomes linear polarized light in the target polarization direction, and then is modulated and reflected by the working medium of sub-area 1 of the two-dimensional spatial light modulator 7; the reflected light enters the semi-reflecting prism 5 again, and after two reflections, it passes through the 1 / 4 wave plate 8, and is modulated and reflected by the working medium of sub-area 2 of the two-dimensional spatial light modulator 7; the twice-modulated reflected light passes through the 1 / 4 wave plate 8, the reflection surface 9-1 of the second total reflection prism and the analyzer 10 in sequence and is emitted.

[0041] The semi-reflective prism 5 includes a semi-reflective corner cube prism or a semi-reflective Dove prism. The cross section of the semi-reflective corner cube prism is an isosceles right triangle, and its two semi-transparent and semi-reflective surfaces are seamlessly bonded with the first total reflection prism anti-reflection surface 4-2 and the second total reflection prism anti-reflection surface 9-2 of equal areas. The cross section of the Dove prism is an isosceles trapezoid, and its two semi-transparent and semi-reflective surfaces are seamlessly bonded with the first total reflection prism anti-reflection surface 4-2 and the second total reflection prism anti-reflection surface 9-2 of equal areas, and the areas can be different. That is, as long as the semi-reflective prism can achieve the parallelism of the incident light and the outgoing light, it can be used as the semi-reflective prism 5 of the present invention.

[0042] The polarization directions of the polarizer 6 and the analyzer 10 are parallel; when the polarization direction of the polarizer 6 is parallel to the working polarization direction of the SLM, specific modulation information is loaded to the two-dimensional spatial light modulator 7, and its position is moved laterally and the direction angle and pitch angle are adjusted, and the light field distribution characteristics of the emergent light are observed, so that precise alignment of spatial pixels can be achieved, thereby realizing multi-beam generation with arbitrary number of two-dimensional beams, arbitrary deflection angles and arbitrary power intensity.

[0043] The first total reflection prism reflection surface 4-1 is a metal-coated total reflection surface, and the first total reflection prism anti-reflection surface 4-2 and the first total reflection prism inclined surface 4-3 are multi-layer coating anti-reflection surfaces;

[0044] The first semi-transparent semi-reflective surface 5-1 and the second semi-transparent semi-reflective surface 5-2 of the semi-reflective prism 5 are polarization-maintaining semi-transparent semi-reflective surfaces, and the bottom surface 5-3 of the semi-reflective prism is a multi-layer coated anti-reflective surface;

[0045] The second total reflection prism reflecting surface 9-1 is a metal-coated total reflection surface, and the second total reflection prism anti-reflection surface 9-2 and the second total reflection prism inclined surface 9-3 are multi-layer coated anti-reflection surfaces.

[0046] like Figure 2 As shown, a method for generating arbitrary two-dimensional multi-beams of laser beams according to the present invention is implemented by using the system for generating arbitrary two-dimensional multi-beams of laser beams according to the present invention, and the specific steps are as follows:

[0047] The specific steps are as follows:

[0048] Step 1, build the system and calibrate: build a laser two-dimensional arbitrary multi-beam generation system according to the optical path. The system parameters built in this embodiment are shown in Table 1.

[0049] Table 1

[0050] parameter Numeric caliber 7.68mm Resolution 512×512 Pixel size 15×15μm Working wavelength 632.8nm Laser diameter after beam expansion 10mm

[0051] After the system is built, load specific modulation information to the two-dimensional spatial light modulator, move its position laterally, adjust the azimuth and elevation angles, and observe the light field distribution characteristics of the outgoing light. In the initial state, the amplitude and phase modulation pixels are aligned in space, and their near field distribution is as follows: Figure 3 As shown in (a), when a sharp black cross appears in the near field (the electric field of the light emitted from the analyzer, the two-dimensional space of the near field is a right-handed coordinate system, the x' direction is the horizontal direction, the y' direction is the vertical direction, and the origin is at the center of the two-dimensional spatial light modulator), the amplitude and phase modulation pixels have been precisely aligned in space. The near field distribution is as follows: Figure 3 As shown in (b), at this time, the system calibration is completed and the spatial position and state of the two-dimensional spatial light modulator are locked;

[0052] Step 2: Set the target beam angle and power coefficient: Set the number of target beams n, the two-dimensional deflection angle θ of each beam xy (1),θ xy (2),…,θ xy (n) and the corresponding power coefficients a1, a2, ..., a n , where (x, y) is the far-field two-dimensional spatial coordinate; in this embodiment, the number of target beams is set to 29, and the maximum absolute value of the two-dimensional deflection angle of each beam is 0.1°. The two-dimensional angle coordinates form a "Tai Chi diagram" distribution in space, and the corresponding power coefficient is:

[0053]

[0054] The above 29 beams are all within the polarization angle range that can be achieved by the system.

[0055] Step 3: Calculate the two-dimensional phase modulation of the target angle beam: The phase used to generate the nth beam at the near-field two-dimensional spatial coordinate (x′, y′) is:

[0056]

[0057] Where k0 is the spatial frequency of the beam, θ x (n) and θ y (n) are the two-dimensional space angles θ xy (n) The angles in the x′ and y′ directions respectively; by modifying the coefficient a n To adjust the deflection angle to (θ x (n), θ y (n)) beam power purpose;

[0058] Near field E at coordinate (x′, y′) near (x′y′), total phase φ(x′y′), and amplitude A(x′y′) are:

[0059]

[0060] Among them, MAX is The maximum value of and They represent the phase modulation required for the near-field coordinate point (x′y′) corresponding to the ξth, ηth and mth beams in space respectively;

[0061] This embodiment calculates the near-field amplitude-phase co-modulation data matrix corresponding to the far-field beam "Tai Chi diagram" distribution, such as Figure 4 The matrix information is introduced into the simulation model of a laser two-dimensional arbitrary multi-beam forming system described in the present invention, and the simulation effect is obtained as shown in FIG. Figure 5 As shown, the simulation results meet the design requirements.

[0062] Step 4: Load the phase modulation signal: According to the spatial light modulator phase-voltage mapping table, find the A of the near-field coordinate point (x′y′) (x′y′) The voltage values ​​corresponding to φ(x′y′) are calculated and the voltage matrices of sub-area 1 and sub-area 2 of the two-dimensional spatial light modulator are generated. Finally, a complete voltage bitmap is merged and loaded into the two-dimensional spatial light modulator to realize arbitrary two-dimensional multi-beam agile pointing and power allocation. Observe the experimental results of the laser far-field distribution, such as Figure 6 As shown in the figure, the 29 beams are distributed in different positions, and the light intensity envelopes presented by different powers at different angles form a distinct "Tai Chi diagram" distribution. The experimental results are consistent with the expected design results, achieving the design purpose, and successfully realizing the arbitrary multi-beam agile pointing of the two-dimensional "Tai Chi diagram" far-field distribution, verifying the theoretical scientificity and experimental feasibility of the present invention.

[0063] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A laser two-dimensional arbitrary multi-beam generating system, characterized in that: It comprises a laser (1), a beam expander (2), a half-wave plate (3), a first total reflection prism (4), a second total reflection prism (9), a semi-reflection prism (5), a polarizer (6), a two-dimensional spatial light modulator (7), a quarter-wave plate (8) and an analyzer (10); In the spatial structure, the 90° prism vertex angles of the first total reflection prism (4) and the second total reflection prism (9) are inwardly oriented, and the first total reflection prism inclined surface (4-3) and the second total reflection prism inclined surface (9-3) are outwardly oriented and parallel to each other; the semi-reflection prism (5) comprises two symmetrical semi-transparent and semi-reflective surfaces, and a semi-reflective prism bottom surface (5-3) perpendicular to the first total reflection prism inclined surface (4-3) and the second total reflection prism inclined surface (9-3); the first total reflection prism anti-reflection surface (4-2) and the first semi-transparent and semi-reflective surface (5-1) of the semi-reflection prism (5) are seamlessly bonded, and the second total reflection prism anti-reflection surface (9-2) and the second semi-transparent and semi-reflective surface (5-2) of the semi-reflection prism (5) are seamlessly bonded; the cross-section of the structure formed by the first total reflection prism (4), the second total reflection prism (9) and the semi-reflection prism bottom surface (5-3) is in the shape of a "district"; The two-dimensional spatial light modulator (7) is located outside the bottom surface (5-3) of the semi-reflective prism, and the analyzer (10) is located outside the inclined surface (9-3) of the second total reflection prism; the polarizer (6) and the quarter wave plate (8) are arranged in parallel between the two-dimensional spatial light modulator (7) and the bottom surface (5-3) of the semi-reflective prism; the half wave plate (3), the beam expander (2) and the laser (1) are arranged in sequence outside the inclined surface (4-3) of the first total reflection prism; The two-dimensional spatial light modulator (7) is spatially divided into two regions: sub-region 1 cooperates with the polarizer (6) for phase modulation; sub-region 2 and the quarter wave plate (8) form a reflective polarization rotator, which is combined with the analyzer (10) to achieve amplitude modulation; The fine light beam output by the laser (1) passes through a beam expander (2) to form a wide-diameter plane wave coarse light beam, and the coarse light beam passes through a 1 / 2 wave plate (3) and enters a first total reflection prism (4), and after being totally reflected by a reflection surface (4-1) of the first total reflection prism, enters a semi-reflection prism (5), and after passing through a polarizer (6), becomes linearly polarized light, and is then modulated and reflected by a working medium of sub-area 1 of a two-dimensional spatial light modulator (7); After the reflected light enters the semi-reflective prism (5) again, it is reflected twice and then passes through a quarter wave plate (8), and is modulated and reflected by the working medium of sub-area 2 of the two-dimensional spatial light modulator (7); the twice-modulated reflected light passes through the quarter wave plate (8), the second total reflection prism reflection surface (9-1) and the analyzer (10) in sequence and then is emitted.

2. A laser two-dimensional arbitrary multi-beam generating system according to claim 1, characterized in that: The polarization directions of the polarizer (6) and the analyzer (10) are parallel; The first total reflection prism reflection surface (4-1) is a metal-coated total reflection surface, and the first total reflection prism anti-reflection surface (4-2) and the first total reflection prism inclined surface (4-3) are multi-layer coating anti-reflection surfaces; The first semi-transparent semi-reflective surface (5-1) and the second semi-transparent semi-reflective surface (5-2) of the semi-reflective prism (5) are polarization-maintaining semi-transparent semi-reflective surfaces, and the bottom surface (5-3) of the semi-reflective prism is a multi-layer coating anti-reflection surface; The second total reflection prism reflection surface (9-1) is a metal-coated total reflection surface, and the second total reflection prism anti-reflection surface (9-2) and the second total reflection prism inclined surface (9-3) are multi-layer-coated anti-reflection surfaces.

3. The laser two-dimensional arbitrary multi-beam generating system according to claim 1, characterized in that: The semi-reflective prism (5) comprises a semi-reflective corner cube prism or a semi-reflective Dove prism.

4. A method for generating two-dimensional arbitrary multi-beams of laser, implemented by using the two-dimensional arbitrary multi-beams of laser generating system according to any one of claims 1 to 3, characterized in that: The specific steps are as follows: Step 1, build the system and calibrate: build a laser two-dimensional arbitrary multi-beam generation system according to the optical path, load specific modulation information to the two-dimensional spatial light modulator, move its position laterally and adjust the azimuth angle and pitch angle, observe the light field distribution characteristics of the outgoing light, when a sharp black cross appears in the near-field distribution, the amplitude and phase modulation pixels have been accurately aligned in space, and the spatial position and state of the two-dimensional spatial light modulator are locked; Step 2: Set the target beam angle and power coefficient: Set the number of target beams n, the two-dimensional deflection angle θ of each beam xy (1),θ xy (2),…,θ xy (n) and the corresponding power coefficients a1, a2, …, a n , where (x, y) is the far-field two-dimensional space coordinate; Step 3: Calculate the two-dimensional phase modulation of the target angle beam: The phase used to generate the nth beam at the near-field two-dimensional spatial coordinate (x′, y′) is: Where k0 is the spatial frequency of the beam, θ x (n) and θ y (n) are the two-dimensional space angles θ xy (n) Angles in the x′ and y′ directions respectively; Near field E at coordinate (x′, y′) near (x′y′), total phase φ(x′y′), and amplitude A(x′y′) are: Among them, MAX is The maximum value of and They represent the phase modulation required for the near-field coordinate point (x′y′) corresponding to the ξth, ηth and mth beams in space respectively; Step 4: Load the phase modulation signal: According to the spatial light modulator phase-voltage mapping table, find the A of the near-field coordinate point (x′y′) (x′y′) The voltage values ​​corresponding to φ(x′y′) are obtained, and the voltage matrices of sub-area 1 and sub-area 2 of the two-dimensional spatial light modulator are generated, which are finally merged into a complete voltage bitmap, which is loaded into the two-dimensional spatial light modulator to realize two-dimensional arbitrary multi-beam agile pointing and power allocation.

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