Stacked array high-power laser space beam combining system and method

Abstract

The present application relates to the technical field of laser beam synthesis, and provides a stacked array type high-power laser spatial beam combining synthesis system and method, the present application carries out multi-dimensional synthesis through M high-power fiber laser arrays of different wavelengths for spatial beam combining and spectral array stacking, while maintaining the advantages of the split-aperture spatial beam combining synthesis technology, realizes linear superposition of total power, ensures excellent beam quality of the combined beam, and can effectively control the near-field power density distribution level of the combined beam, reducing the damage risk of related optical elements. In terms of beam quality, the first and second multi-dimensional adjustment modules integrate displacement control, tilt control, focusing and other functions, and through the single-path far-field spot and combined far-field spot monitoring module, the beam quality of all sub-beam lasers and the array beam combining accuracy are monitored in real time, thereby providing technical support for realizing real-time feedback control and ensuring high-quality combined laser.

Description

Technical Field

[0001] This invention relates to the field of laser beam combining technology, specifically a stacked array high-power laser spatial beam combining system and method. Background Technology

[0002] In recent years, fiber lasers have rapidly become the preferred choice for high-power laser sources due to their high beam quality and advantages in miniaturization and lightweight design. However, the maximum output power of individual fiber laser sources is limited by physical mechanisms such as nonlinear effects, optical damage, and thermal damage. Therefore, beam combining technology based on multiple lasers is an essential approach to achieving high-power, high-beam-quality laser sources. Among these technologies, the combining devices in multi-beam spatial beam combining devices are relatively mature, with simple system architecture, high robustness, and ease of achieving high-precision real-time closed-loop control of sub-beam optical axis pointing. This makes it one of the mainstream technologies for laser beam combining.

[0003] However, traditional spatial beamforming design relies on multiple beams arranged and filled in a two-dimensional plane with varying apertures. The duty cycle of the resulting beam is already close to the geometric limit, making it difficult to fully utilize the synthesized aperture. To obtain a higher power output laser source, there are essentially two approaches: increasing the power of a single laser beam or reducing the aperture of a single laser beam to expand the number of beams to fill. However, the shortcomings and drawbacks of these approaches are obvious. The former is limited by the beam quality and power output capability of individual fiber optic sources; the latter, due to the reduced aperture of a single laser beam, significantly increases the power density distribution in the near field, leading to a sharp increase in the damage resistance of optical transmission mirrors. It also weakens the effect of increasing the power density in the far-field beam barrel by the synthesized laser power, reducing the overall synthesis gains.

[0004] Therefore, it is urgent to innovate the traditional spatial beamforming method on the existing basis and propose a spatial beamforming scheme that can effectively improve the beamforming capability while maintaining the system's stability and robustness. Summary of the Invention

[0005] To address the limitations of existing technologies and break through conventional thinking, this invention provides an easy-to-implement, stacked high-power laser spatial beamforming system and method that can further and effectively enhance beamforming capabilities.

[0006] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows: On one hand, the present invention provides a stacked array high-power laser spatial beamforming system, comprising: M fiber optic light source modules, M≥2, are used to output multi-wavelength laser beams. The m-th fiber optic light source module outputs... n mThe path wavelength is l m The laser sub-beams, m=1,2,...,M, and l 1, l 2, ..., l M They are all different; The multidimensional adjustment module is used to independently adjust each laser sub-beam output from each fiber optic light source module in multiple dimensions, including displacement and tilt. Then, the multidimensionally adjusted laser sub-beams from each fiber optic light source module are combined and clustered in the near-field space to form corresponding array surfaces Σ. m ; A spectral-spatial beam combiner, comprising a beam splitter and a dichroic mirror, combines most of the power from M array surfaces Σ. m The superimposed outputs are formed into a composite array surface, while the remaining small portion of the power of the array surface Σ is sampled. m To optical beam-contraction conversion device; Optical beam-shrinking converter, used to convert the sampled array surface Σ m Perform proportional beam shrinking transformation; An optical coupling module is set in the output optical path of the optical beam shrinking conversion device and is used to couple the beams after beam shrinking conversion from different fiber optic light source modules to different monitoring units of the far-field spot monitoring module. The far-field spot monitoring module includes M array surface monitoring units and one beam combining far-field spot monitoring unit, wherein the m-th array surface monitoring unit monitors the array surface Σ in real time. m The far-field spot centroid position and spot shape of each laser sub-beam are monitored, and the far-field spot monitoring unit for beam combining is used to monitor the far-field spot shape of the superimposed output combined array beam in real time.

[0007] Preferably, the multidimensional adjustment module includes a first multidimensional adjustment module, which is used to independently adjust each laser sub-beam output by each fiber optic light source module in multiple dimensions, including displacement and tilt.

[0008] Furthermore, the multi-dimensional adjustment module also includes a second multi-dimensional adjustment module, used to independently axially focus each laser sub-beam output from each fiber optic light source module, optimizing and adjusting the far-field spot shape of each laser sub-beam. Simultaneously, the multi-dimensional adjustment module combines the multi-dimensionally adjusted laser sub-beams output from each fiber optic light source module in the near-field space to form corresponding array surfaces Σ. m .

[0009] Furthermore, on the surface of the composite array, the centers of the light spots of all the individual laser sub-beams do not coincide and are arranged in an alternating manner.

[0010] Compared with existing spatial beamforming techniques, the stacked array high-power laser spatial beamforming system provided by this invention has the following advantages: This invention utilizes M fiber laser arrays of different wavelengths for spatial beam joining and spectral stacking to achieve two-dimensional spectral-spatial synthesis. While achieving linear superposition of total power, it ensures excellent beam quality of the synthesized beam and effectively controls the near-field power density distribution, reducing the risk of damage to related optical components. Regarding beam quality, a first and second multi-dimensional adjustment module integrates displacement control, tilt control, and focusing. Simultaneously, a single-path far-field spot and synthesized far-field spot monitoring module provides real-time monitoring of the beam quality of all sub-beams and the array beam synthesis accuracy, thus providing technical support for real-time feedback control and ensuring high-quality synthesized laser. For near-field power density distribution control of the synthesized beam, a preferred method is the relative rotation design between the spatial beam joining array surfaces (or, more preferably, the optimized sub-beam arrangement design on the spatial beam joining array surfaces). This achieves staggered peak arrangement of all sub-beam spots on the spectral stacking surface, providing technical support for reducing the transmission pressure on the optical mirrors of the high-power synthesized beam. The implementation method and type of the first multidimensional adjustment module are not limited. A first multidimensional adjustment module with displacement and tilt adjustment functions can be implemented by setting two reflectors at the output end of the fiber laser. While ensuring tilt control, the two reflectors work together to adjust the near-field position of the beam within a certain range. The implementation method and type of the second multidimensional adjustment module with axial focusing function are also not limited. Without loss of generality, adjustable-focus fiber laser collimators, deformable mirrors, and other devices can be selected as the second multidimensional adjustment module.

[0011] In controlling the near-field power density distribution of the synthesized beam, the staggered arrangement of all sub-beam spots on the spectral stacking surface is preferably achieved through the relative rotation design between the spatial splicing array surfaces (or, preferably through the sub-beam arrangement optimization design on the spatial splicing array surface), which provides technical support for reducing the optical mirror transmission pressure of high-power synthesized beams.

[0012] Specifically, this invention breaks through the power level limitations of individual fiber optic light sources and significantly expands the number of synthesizable lasers to obtain high beam quality laser sources with higher power output.

[0013] This invention achieves a staggered filling design by superimposing all unit sub-beams on multiple planes, which can effectively improve the near-field power density distribution of the synthesized beam and is beneficial to the control of damage risk of optical components.

[0014] This invention is based on the subplane of the synthesized beam array after two-dimensional beam splicing, and uses a dichroic mirror for multi-plane axial superposition. It can follow the mature optomechanical design in existing spatial beam splicing synthesis methods and is easy to implement. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of a novel stacked array high-power laser spatial beamforming system provided in one embodiment; Figure 2 This is a schematic diagram of the beam filling arrangement of a stacked array of high-power laser spatial beam splicing in one embodiment; Figure 3 This is a simulation comparison of the near-field power density distribution of the synthesized beam in one embodiment. Figure 3 (a) shows the simulation diagram of the near-field power density distribution of the first fiber optic light source module bundled and synthesized array surface Σ1. Figure 3 (b) shows the synthesized array surface Σ when the first and second fiber optic light source modules are not misaligned. 1+2 Simulation diagram of near-field power density distribution. Figure 3 In section (c), a staggered design is implemented for the first and second fiber optic light source modules to achieve a superimposed output synthesized array surface Σ. 1+2 Simulation diagram of the near-field power density distribution of the composite array surface when the centers of the laser beams of all sub-beams do not coincide and are arranged in an alternating manner; Figure 4 This is a schematic diagram of the stacked array high-power laser spatial beam splicing and synthesis beam filling arrangement in another embodiment; Explanation of the labels in the diagram: 1. First fiber optic light source module; 2. Second fiber optic light source module; 3. Beam splitter; 4. Dichroic mirror; 5. Far-field spot monitoring module; 6. First multi-dimensional adjustment module; 7. Second multi-dimensional adjustment module; 8. Optical beam-shrinking conversion device; 9. Optical coupling module; 1-1, The first wavelength is l 1. Fiber laser; 1-2. The second wavelength is... l A fiber laser of size 1; 1- i , No. i Each wavelength is l 1- Fiber laser; 1- n 1. No. n 1 wavelength is l 1 fiber laser; 2-1, The first wavelength is l 2. Fiber laser; 2-2. The second wavelength is l 2- Fiber laser; 2- j , No. j Each wavelength is l 2 fiber lasers; 1- n 2. No. n 2 wavelengths l 2 fiber lasers; 5-1, First array surface monitoring unit; 5-2, Second array surface monitoring unit; 5-3, Beam combining far-field spot monitoring unit; 9-1, First beam splitter; 9-2, Second beam splitter; 9-3, Third beam splitter; 9-4, Reflector. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0018] To overcome the power level limitations of individual fiber optic light sources and significantly expand the number of synthesizable lasers, one embodiment provides a stacked array high-power laser spatial beamforming system, comprising: M fiber optic light source modules, M≥2, are used to output multi-wavelength laser beams. The m-th fiber optic light source module outputs... n m The path wavelength is l m The laser sub-beams, m=1,2,...,M, and l 1, l 2, ..., l M They are all different; The multidimensional adjustment module is used to independently adjust each laser sub-beam output from each fiber optic light source module in multiple dimensions, including displacement and tilt. Then, the multidimensionally adjusted laser sub-beams from each fiber optic light source module are combined and clustered in the near-field space to form corresponding array surfaces Σ. m ; A spectral-spatial beam combiner, comprising a beam splitter and a dichroic mirror, combines most of the power from M array surfaces Σ. m The superimposed outputs are formed into a composite array surface, while the remaining small portion of the power of the array surface Σ is sampled. m To optical beam-contraction conversion device; Optical beam-shrinking converter, used to convert the sampled array surface Σ m Perform proportional beam shrinking transformation; An optical coupling module is set in the output optical path of the optical beam shrinking conversion device and is used to couple the beams after beam shrinking conversion from different fiber optic light source modules to different monitoring units of the far-field spot monitoring module. The far-field spot monitoring module includes M array surface monitoring units and one beam combining far-field spot monitoring unit, wherein the m-th array surface monitoring unit monitors the array surface Σ in real time. m The far-field spot centroid position and spot shape of each laser sub-beam are monitored, and the far-field spot monitoring unit for beam combining is used to monitor the far-field spot shape of the combining array surface in real time.

[0019] The m-th fiber optic light source module contains n m The wavelength of the station is l m Fiber lasers for output n m The path wavelength is l m The laser sub-beam.

[0020] The multi-dimensional adjustment module includes a first multi-dimensional adjustment module, with each fiber laser in each fiber source module corresponding to a first multi-dimensional adjustment module. Each first multi-dimensional adjustment module is used for displacement and tilt control of a single laser sub-beam. The displacement control of each first multi-dimensional adjustment module ensures that each single laser sub-beam is filled in a preset arrangement on its corresponding array surface. The tilt control of each first multi-dimensional adjustment module dynamically adjusts the optical axis direction of the corresponding laser sub-beam based on the centroid position of its far-field spot, ensuring that all laser sub-beams are emitted in parallel, resulting in optimal far-field beam combining effect. Furthermore, the multi-dimensional adjustment module also includes a second multi-dimensional adjustment module, each with axial focusing capabilities for a single laser sub-beam, enabling optimized adjustment of the far-field spot shape of each laser sub-beam.

[0021] Unlike traditional spatial beam combining schemes that only involve arranging and filling multiple beams and stitching apertures within a two-dimensional plane, the above embodiment performs multiple superpositions of the combined beam array plane after multiple two-dimensional beams in the axial direction. Specifically, it employs a spectral-spatial beam combining device to achieve the superposition of the array plane Σ after multiple two-dimensional beams. m By performing axial spatial stacking, the above embodiments can significantly expand the number of synthesizable lasers, thereby obtaining a high-beam-quality laser source with higher power output. Each array surface Σ m The wavelengths of the laser sub-beams within the array remain consistent, while the wavelengths of the different array surfaces Σ m Different laser wavelengths are output, and all laser sub-beams maintain parallel optical axes during emission. Each array surface Σ mThe power and aperture of the laser sub-beams can be designed based on a comprehensive consideration of the combined power requirements and the tolerance of the optical transmission mirrors.

[0022] Specifically, the synthesis method of the stacked high-power laser spatial beamforming system provided in the above embodiments includes the following steps: S1, activate M fiber optic light source modules, the m-th fiber optic light source module outputs... n m The path wavelength is l m The laser sub-beams, m=1,2,...,M, and l 1, l 2, ..., l M They are all different; S2, through a multi-dimensional adjustment module, each laser sub-beam output from each fiber optic light source module is independently adjusted in multiple dimensions. This multi-dimensional adjustment includes displacement control and tilt control. The goal of displacement control is to ensure that the laser sub-beams output from each fiber optic light source module are bundled and synthesized in the near-field space to the corresponding array surface Σ. m The laser beams are arranged and filled according to the preset beam array; the goal of tilt control is to dynamically adjust the optical axis direction of the corresponding laser sub-beams to ensure that all laser sub-beams are emitted in parallel. S3 utilizes a spectral-spatial beam combiner composed of a beam splitter and a dichroic mirror. On one hand, the spectral-spatial beam combiner combines M array surfaces Σ m Spectral screening and spatial superposition are performed, and a Σ array consisting of M array planes is superimposed along the z-axis. m The synthesized array surface; on the other hand, the spectral-spatial beam combiner samples and outputs each array surface Σ. m A low-power beam is used for monitoring and feedback control; S4, the sampled array surfaces Σ m After being proportionally reduced by the optical beam-reduction conversion device, it is guided to the far-field spot monitoring module through the optical coupling module; S5, the far-field spot monitoring module utilizes its M array surface monitoring units to monitor the corresponding array surface Σ in real time. m The centroid position and spot shape of the far-field spot of each laser sub-beam are monitored; the far-field spot shape of the synthesized array surface is monitored in real time using the beam combining far-field spot monitoring unit. S6, based on the array surface Σ monitored in real time by the m-th array surface monitoring unit. mThe centroid position of the far-field spot of each laser sub-beam is dynamically adjusted by the tilt control function of each first multi-dimensional adjustment module in the multi-dimensional adjustment module to ensure that all laser sub-beams are emitted in parallel. At the same time, based on the far-field spot morphology data of each laser sub-beam, the axial focusing function of each second multi-dimensional adjustment module in the multi-dimensional adjustment module is used to optimize and adjust the far-field spot morphology of the corresponding laser sub-beam.

[0023] The above embodiments utilize spatial beamforming and spectral stacking of M high-power fiber laser arrays of different wavelengths for multidimensional synthesis. While maintaining the advantages of aperture-splitting spatial beamforming technology, this approach achieves linear superposition of total power, ensuring excellent beam quality and effectively controlling the near-field power density distribution of the synthesized beam, thus reducing the risk of damage to related optical components. Regarding beam quality, the first and second multidimensional adjustment modules integrate displacement control, tilt control, and focusing functions. Simultaneously, a single-path far-field spot and synthesized far-field spot monitoring module provides real-time monitoring of the beam quality of all sub-beams and the array beam synthesis accuracy, thereby providing technical support for real-time feedback control and ensuring high-quality synthesized lasers.

[0024] To clearly illustrate the specific implementation of the present invention, the present invention will be described in detail below using M=2 as an example: like Figure 1 As shown, the stacked array high-power laser spatial beamforming system in this embodiment includes: The first fiber optic light source module 1 is used for output. n 1 channel wavelength is l A laser sub-beam of 1.

[0025] The second fiber optic light source module 2 is used for output. n 2-channel wavelength l 2 laser sub-beams, l 1≠ l 2, n 1. n The value of 2 is unlimited, and all values ​​are greater than or equal to 3.

[0026] The second multi-dimensional adjustment module 7 is used to independently focus each laser sub-beam output by each fiber optic light source module along the axis, and optimize and adjust the spot shape of the far-field spot of each laser sub-beam. The first multi-dimensional adjustment module 6 is used for... n 1 channel wavelength is l 1 laser sub-beam, n 2-channel wavelength l The two laser sub-beams are each independently adjusted in multiple dimensions, including displacement control and tilt control. The multidimensionally adjusted... n 1 channel wavelength is lThe laser sub-beams of 1 are spliced ​​together in the near-field space, and the output of the spliced ​​array surface Σ1 is sent to the beam splitter 3. The multidimensionally adjusted... n 2-channel wavelength l The laser sub-beams of 2 are spliced ​​and synthesized in the near-field space, and the output of the spliced ​​array surface Σ2 is sent to the dichroic mirror 4.

[0027] Beam splitter 3, for wavelength l 1. The laser has high reflectivity, reflecting most of the power of the array surface Σ1 onto the dichroic mirror 4.

[0028] Dichroic mirror 4, wavelength l 1. High laser transmittance, wavelength-sensitive l 2. High laser reflectivity: The majority of the power is reflected from the array surface Σ2 and transmitted from the array surface Σ1. The two are superimposed to form the output of the composite array surface Σ. 1+2 .

[0029] The optical beam-shrinking conversion device 8 is used to perform proportional beam-shrinking conversion on the array surface Σ1 transmitted through the beam splitter 3 and the array surface Σ2 transmitted through the dichroic mirror 4.

[0030] The optical coupling module 9 is set in the output optical path of the optical beam-converting device 8.

[0031] The far-field spot monitoring module 5 receives the beam after beam reduction transformation through the optical coupling module 9 and monitors the spot state.

[0032] The first fiber optic light source module 1 includes n 1 unit with wavelength l 1 fiber laser, with the first wavelength being... l 1. Fiber laser 1-1, the second wavelength is l 1. Fiber laser 1-2, the first i Each wavelength is l 1- Fiber laser 1- i ,...,No. n 1 wavelength is l 1- Fiber laser 1- n 1.

[0033] The second fiber optic light source module 2 includes n 2 units with wavelength l 2 fiber lasers, with the first wavelength being... l 2. Fiber laser 2-1, the second wavelength is l 2 fiber lasers 2-2, the first j Each wavelength is l 2- Fiber laser j , No. n 2 wavelengths l2 fiber lasers 1- n 2.

[0034] Each fiber laser in the first fiber light source module 1 and the second fiber light source module 2 corresponds to a second multi-dimensional adjustment module 7 and a first multi-dimensional adjustment module 6, respectively. Each second multi-dimensional adjustment module 7 independently performs axial focusing on each laser sub-beam, optimizing and adjusting the far-field spot shape of each laser sub-beam. Each first multi-dimensional adjustment module 6 is used for displacement control and tilt control of a single laser sub-beam. The displacement control is used to ensure that each single laser sub-beam is filled in a preset arrangement on the corresponding array surface. Furthermore, to make the near-field power density distribution of the synthesized beam more uniform and the peak power density lower, the synthesized array surface Σ... 1+2 Above, the centers of the laser beams of all single-path laser sub-beams do not overlap and are arranged in an alternating pattern.

[0035] The far-field spot monitoring module 5 includes a first array surface monitoring unit 5-1 for real-time monitoring of the centroid position and spot shape of the far-field spot of each laser sub-beam in array surface Σ1, a second array surface monitoring unit 5-2 for real-time monitoring of the centroid position and spot shape of the far-field spot of each laser sub-beam in array surface Σ2, and a beam combining far-field spot monitoring unit 5-3 for real-time monitoring of the far-field combining effect of the array beam.

[0036] The optical coupling module 9 includes a first beam splitter 9-1, a second beam splitter 9-2, a third beam splitter 9-3, and a reflector 9-4. The array surface Σ1 transmitted through the beam splitter 3 is proportionally reduced by the optical beam-shortening device 8 and then incident on the first beam splitter 9-1. A portion of the light is transmitted through the first beam splitter 9-1 to the first array surface monitoring unit 5-1, and another portion is reflected by the first beam splitter 9-1 to the reflector 9-4, and then reflected by the reflector 9-4 to the second beam splitter 9-2. The array surface Σ2 transmitted through the dichroic mirror 4 is proportionally reduced by the optical beam-shortening device 8 and then incident on the third beam splitter 9-3. A portion of the light is transmitted through the third beam splitter 9-3 to the second array surface monitoring unit 5-2, and another portion is reflected by the third beam splitter 9-3 to the second beam splitter 9-2. The second beam splitter 9-2 superimposes the two light sources and outputs them to the beam combining far-field spot monitoring unit 5-3.

[0037] In the above embodiments, each second multi-dimensional adjustment module 7 has a single-path laser sub-beam axial focusing function, which can optimize and adjust the spot shape of the far-field spot of each laser sub-beam. The tilt control of each first multi-dimensional adjustment module 6 dynamically adjusts the optical axis direction of the corresponding laser sub-beam based on the centroid position of the far-field spot of the corresponding laser sub-beam, ensuring that all laser sub-beams are emitted in parallel, and the far-field synthesis effect of the array beam is optimal.

[0038] based on Figure 1The synthesis method of the stacked array high-power laser spatial beamforming system shown includes the following steps: S1, start the first fiber optic light source module 1 and the second fiber optic light source module 2, and output all laser sub-beams; S2, through a multi-dimensional adjustment module, each laser sub-beam output from each fiber optic light source module is independently adjusted in multiple dimensions. This multi-dimensional adjustment includes displacement control and tilt control. The goal of displacement control is to ensure that the laser sub-beams output from each fiber optic light source module are bundled and synthesized in the near-field space to the corresponding array surface Σ. m The laser beams are arranged and filled according to a preset beam array. The goal of tilt control is to dynamically adjust the optical axis direction of the corresponding laser sub-beams to ensure that all laser sub-beams are emitted in parallel. Specifically, in this embodiment, the multi-dimensional adjustment module includes a second multi-dimensional adjustment module 7 and a first multi-dimensional adjustment module 6. Each second multi-dimensional adjustment module 7 independently focuses each laser sub-beam along its axis, optimizing the far-field spot shape of each laser sub-beam. Each first multi-dimensional adjustment module 6 performs displacement control and tilt control on each laser sub-beam. Then, the multi-dimensionally adjusted... n 1 channel wavelength is l The laser sub-beams of 1 are spliced ​​together in the near-field space, and the output of the spliced ​​array surface Σ1 is sent to the beam splitter 3. The multidimensionally adjusted... n 2-channel wavelength l The laser sub-beams of 2 are spliced ​​and synthesized in the near-field space, and the output of the spliced ​​array surface Σ2 is sent to the dichroic mirror 4.

[0039] S3, beam splitter 3, and dichroic mirror 4 constitute a spectral-spatial beam combiner. l The laser has high reflectivity, reflecting most of the power from the array surface Σ1 to the dichroic mirror 4. The wavelength of the dichroic mirror 4 is... l 1. High laser transmittance, wavelength-sensitive l 2. High laser reflectivity: The majority of the power is reflected from the array surface Σ2 and transmitted from the array surface Σ1. The two are superimposed to form the output of the composite array surface Σ. 1+2 Among them, the array surface Σ1 of the trace power transmitted from the beam splitter 3 and the array surface Σ2 of the trace power transmitted from the dichroic mirror 4 are used for subsequent monitoring and feedback control; S4, the array surface Σ1 of small power transmitted from the beam splitter 3 and the array surface Σ2 of small power transmitted from the dichroic mirror 4 are proportionally converted by the optical beam-shrinking conversion device 8 and then guided to the far-field spot monitoring module 5 through the optical coupling module 9. S5, the far-field spot monitoring module 5 monitors the wavelength in real time as... l 1. Wavelength is lThe far-field spot of each laser sub-beam of 2 is obtained, and the centroid position and spot shape data of the far-field spot of each laser sub-beam are acquired. At the same time, the far-field composite spot of the array beam after being superimposed and synthesized by the dichroic mirror 4 is monitored in real time. S6, based on the centroid position of the far-field spot of each laser sub-beam, dynamically adjusts the optical axis direction of the corresponding laser sub-beam through the tilt control function of each first multi-dimensional adjustment module 6, so that all laser sub-beams are emitted in parallel; at the same time, based on the far-field spot morphology data of each laser sub-beam, optimizes and adjusts the far-field spot morphology of the corresponding laser sub-beam through the axial focusing function of each second multi-dimensional adjustment module 7.

[0040] based on Figure 1 The structure of the stacked array high-power laser spatial beamforming system shown in one embodiment includes a first fiber optic light source module 1 comprising 6 equal-power lasers with wavelengths of [missing information]. l The first fiber laser is a fiber laser, and the second fiber light source module 2 contains 6 equal-power fiber lasers with wavelengths of [wavelength value missing]. l 2 fiber lasers, such as Figure 2 As shown, the laser sub-beams output by the first fiber optic light source module 1 and the second fiber optic light source module 2 are axially superimposed and spliced ​​together within a circular composite light-transmitting aperture.

[0041] Under the constraints of traditional methods, the sub-bundle arrangement within the splicing and synthesizing array surface Σ1 of a fiber optic light source module, such as the first fiber optic light source module 1, is close to the geometric design limit, but the synthesized light-passing aperture is still not fully filled. The innovative method provided by this invention includes two fiber optic light source modules, which can follow the mature optomechanical design of traditional methods for splicing and synthesizing. After the output synthesized array surface is axially superimposed through a dichroic mirror 4, the number of synthesized lasers is doubled, and the output power of the synthesized laser is correspondingly doubled, and this method is easy to implement.

[0042] Preferably, in another embodiment, the array surface Σ can be obtained by rotating the splicing and arrangement design of the second fiber optic light source module 2 by a certain angle. 2, so that the superimposed output synthesized array surface Σ 1+2 The centers of all laser sub-beams within the array are non-coincident and staggered. This achieves staggered filling and non-overlapping of all beams, increasing the beam duty cycle within the synthesized aperture by approximately 25%, while simultaneously improving the beam relative to the synthesized array surface Σ. 1+2 Its synthesized beam has a more uniform near-field power density distribution and a lower peak power density.

[0043] like Figure 3 As shown, Figure 2 The simulation comparison diagram of the near-field power density distribution of the synthesized beam in the embodiment shown is as follows: Figure 3 (a) shows the simulation diagram of the near-field power density distribution of the first fiber optic light source module bundled and synthesized array surface Σ1. Figure 3 (b) shows the synthesized array surface Σ when the first and second fiber optic light source modules are not misaligned. 1+2 Simulation diagram of near-field power density distribution. Figure 3 In section (c), the first and second fiber optic light source modules are misaligned to achieve the superimposed output synthesized array surface Σ. 1+2 The composite array surface Σ when the centers of all laser sub-beams do not coincide and are staggered 1+2 The near-field power density distribution simulation diagram. Assuming all fiber lasers participating in the beam splicing and superposition have equal power output, the simulation results are based on the Gaussian distribution characteristics of single-mode fiber laser beams. Figure 3 As shown in the figure, the use of Figure 2 In a preferred embodiment, the array surface Σ is obtained by rotating the bundled arrangement of the second fiber optic light source module 2 by 30 degrees. 2, which allows the superimposed output synthesized array surface Σ 1+2 The centers of all laser sub-beams within the array are non-coincident and staggered, enabling the superimposed output to synthesize the array surface Σ. 1+2 The laser power density distribution within the array is more uniform, and the peak power density is relatively higher than that of the array surface Σ. 1+2 The pressure on optical transmission mirrors from high-power laser irradiation is reduced by approximately 28%.

[0044] like Figure 4 As shown, based on Figure 1 The structure of the stacked array high-power laser spatial beamforming system is shown, providing a stacked array high-power laser spatial beamforming system, wherein the first fiber optic source module 1 includes 7 equal-power lasers with wavelengths of [missing information]. l The first fiber laser is a fiber laser, and the second fiber light source module 2 contains 12 equal-power fiber lasers with wavelengths of [missing information]. l 2 fiber lasers.

[0045] The first fiber optic light source module 1 and the second fiber optic light source module 1, corresponding to the splicing array surface Σ1, are axially superimposed and spliced ​​together within a circular combining aperture. Compared to a single splicing array surface (taking array surface Σ1 as an example), the stacked splicing method can effectively expand the number of synthesizable laser sub-beams and further improve the output power of the synthesized laser, increasing the duty cycle of the synthesized beam by approximately 17%.

[0046] As can be seen from the above embodiments, the number of laser sub-beams output by each fiber optic light source module is not limited in this invention. The arrangement shape of the splicing and combining array surface corresponding to each fiber optic light source module is also not limited and can be reasonably designed based on actual needs.

[0047] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A stacked array high-power laser spatial beamforming system, characterized in that, include: M fiber optic light source modules, M≥2, are used to output multi-wavelength laser beams. The m-th fiber optic light source module outputs... n m The path wavelength is λ m The laser sub-beams, m=1,2,...,M, and λ 1, λ 2, ..., λ M They are all different; A multi-dimensional adjustment module is used to independently adjust each laser beam output by each fiber laser source module in multiple dimensions including displacement and inclination, and to combine the adjusted laser beams in near-field space to form corresponding array surfaces Σ m ; The spectral-spatial beam combiner includes a beam splitter and a dichroic mirror. The dichroic mirror is used for multi-plane axial superposition to achieve the beam combining of multiple two-dimensional array surfaces Σ. m Axial spatial superposition is performed, and the M array surfaces Σ, which account for most of the power, are combined. m The superimposed outputs are formed into a composite array surface, while the remaining small portion of the power of the array surface Σ is sampled. m The optical beam-shrinking device, wherein on the synthesizing array surface, the centers of the light spots of all single laser sub-beams do not coincide with each other and are arranged in an alternating manner, so that the laser power density distribution in the synthesizing array surface is uniform and the peak power density is reduced. Optical beam-shrinking converter, used to convert the sampled array surface Σ m Perform proportional beam shrinking transformation; An optical coupling module is set in the output optical path of the optical beam shrinking conversion device and is used to couple the beams after beam shrinking conversion from different fiber optic light source modules to different monitoring units of the far-field spot monitoring module. The far-field spot monitoring module includes M array surface monitoring units and one beam combining far-field spot monitoring unit, wherein the m-th array surface monitoring unit monitors the array surface Σ in real time. m The far-field spot centroid position and spot shape of each laser sub-beam are monitored, and the far-field spot monitoring unit for beam combining is used to monitor the far-field spot shape of the combining array surface in real time.

2. The stacked array high-power laser spatial beamforming system according to claim 1, characterized in that, The fiber optic light source module includes a first fiber optic light source module and a second fiber optic light source module, M=2; the spectral-spatial beam combiner includes a beam splitter and a dichroic mirror. The multi-dimensional adjustment module will n 1 channel wavelength is λ The laser sub-beams of 1 are bundled together in the near field to form an array surface Σ1, which is then output to the beam splitter. n 2-channel wavelength λ The laser sub-beams of 2 are bundled together in the near field space to form an array surface Σ2, which is then output to the dichroic mirror. Beam splitter for wavelength λ 1. The laser has high reflectivity, reflecting most of the power of the array surface Σ1 to the dichroic mirror; Dichroic mirror wavelength λ 1. High laser transmittance, wavelength-sensitive λ 2. High laser reflectivity: The majority of the power is reflected from the array surface Σ2 and transmitted from the array surface Σ1. The two are superimposed to form the output of the composite array surface Σ. 1+2 ; The optical beam-shrinking conversion device performs proportional beam-shrinking conversion on the array surface Σ1 transmitted through the beam splitter and the array surface Σ2 transmitted through the dichroic mirror.

3. The stacked array high-power laser spatial beamforming system according to claim 1 or 2, characterized in that, The m-th fiber optic light source module includes n m The wavelength of the station is λ m Fiber lasers.

4. The stacked array high-power laser spatial beamforming system according to claim 2, characterized in that, The multidimensional adjustment module includes a first multidimensional adjustment module. Each fiber laser in the first fiber light source module and the second fiber light source module corresponds to a first multidimensional adjustment module. Each first multidimensional adjustment module is used to perform displacement control and tilt control on a single laser sub-beam. The displacement control of each first multidimensional adjustment module is used to ensure that each single laser sub-beam is filled in a preset arrangement on the corresponding array surface.

5. The stacked array high-power laser spatial beamforming system according to claim 4, characterized in that, The far-field spot monitoring module includes a first array surface monitoring unit for real-time monitoring of the centroid position and spot shape of the far-field spot of each laser sub-beam in array surface Σ1, a second array surface monitoring unit for real-time monitoring of the centroid position and spot shape of the far-field spot of each laser sub-beam in array surface Σ2, and a beam combining far-field spot monitoring unit for real-time monitoring of the far-field combining effect of the array beam.

6. The stacked array high-power laser spatial beamforming system according to claim 5, characterized in that, The optical coupling module includes a first beam splitter, a second beam splitter, a third beam splitter, and a reflector. The array surface Σ1 transmitted through the beam splitter is proportionally reduced by the optical beam-shrinking conversion device and then incident on the first beam splitter. Part of it is transmitted through the first beam splitter to the first array surface monitoring unit, and the other part is reflected by the first beam splitter to the reflector, and then reflected by the reflector to the second beam splitter. The array surface Σ2 transmitted through the dichroic mirror is proportionally reduced by the optical beam-splitting device and then incident on the third beam splitter. Part of it is transmitted through the third beam splitter to the second array surface monitoring unit, and the other part is reflected by the third beam splitter to the second beam splitter. The second beam splitter superimposes the two beams and outputs them to the beam combining far-field spot monitoring unit.

7. The stacked array high-power laser spatial beamforming system according to claim 5, characterized in that, The tilt control of each first multidimensional adjustment module dynamically adjusts the optical axis direction of the corresponding laser sub-beam based on the centroid position of the far-field spot of the corresponding laser sub-beam, ensuring that all laser sub-beams are emitted in parallel and the far-field synthesis effect of the array beam is optimal.

8. The stacked array high-power laser spatial beamforming system according to claim 5, characterized in that, The multi-dimensional adjustment module also includes a second multi-dimensional adjustment module, which is used to independently focus each laser sub-beam output by each fiber optic light source module along the axis and optimize the spot shape of the far-field spot of each laser sub-beam.

9. A synthesis method based on the stacked array high-power laser spatial beamforming system as described in claim 1, characterized in that, Includes the following steps: S1, activate M fiber optic light source modules, the m-th fiber optic light source module outputs... n m The path wavelength is λ m The laser sub-beams, m=1,2,...,M, and λ 1, λ 2, ..., λ M They are all different; S2, through a multi-dimensional adjustment module, each laser sub-beam output from each fiber optic light source module is independently adjusted in multiple dimensions. This multi-dimensional adjustment includes displacement control and tilt control. The goal of displacement control is to ensure that the laser sub-beams output from each fiber optic light source module are bundled and synthesized in the near-field space to the corresponding array surface Σ. m The laser beams are arranged and filled according to the preset beam array; the goal of tilt control is to dynamically adjust the optical axis direction of the corresponding laser sub-beams to ensure that all laser sub-beams are emitted in parallel. S3 utilizes a spectral-spatial beam combiner composed of a beam splitter and a dichroic mirror. On one hand, the spectral-spatial beam combiner combines M array surfaces Σ m Spectral screening and spatial superposition are performed, and a Σ array consisting of M array planes is superimposed along the z-axis. m The synthesized array surface; on the other hand, the spectral-spatial beam combiner samples and outputs each array surface Σ. m A low-power beam is used for monitoring and feedback control; S4, the sampled array surfaces Σ m After being proportionally reduced by the optical beam-reduction conversion device, it is guided to the far-field spot monitoring module through the optical coupling module; S5, the far-field spot monitoring module utilizes its M array surface monitoring units to monitor the corresponding array surface Σ in real time. m The centroid position and spot shape of the far-field spot of each laser sub-beam are monitored; the far-field spot shape of the synthesized array surface is monitored in real time using the beam combining far-field spot monitoring unit. S6, based on the array surface Σ monitored in real time by the m-th array surface monitoring unit. m The centroid position of the far-field spot of each laser sub-beam is dynamically adjusted by the tilt control function of each first multi-dimensional adjustment module in the multi-dimensional adjustment module to ensure that all laser sub-beams are emitted in parallel. At the same time, based on the far-field spot morphology data of each laser sub-beam, the axial focusing function of each second multi-dimensional adjustment module in the multi-dimensional adjustment module is used to optimize and adjust the far-field spot morphology of the corresponding laser sub-beam.

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