System and method for realizing coherent beam combination of semiconductor laser array

Abstract

The invention provides a system and a method for realizing coherent beam combination of a semiconductor laser array. The system comprises a seed source, a collimating mirror, a beam expander, a first beam splitter, the semiconductor laser array, a fast and slow axis collimator, a phase algorithm controller, a beam combiner and a high-speed photoelectric detector which are sequentially arranged along a laser transmission direction, a laser beam emitted by a seed source is collimated by a collimating mirror, the diameter of the laser beam is increased by a beam expander, and then the laser beam is divided into a plurality of sub-beams by a first beam splitter; respectively coupling and inputting the plurality of sub-beams into a semiconductor laser array for optical signal amplification; the amplified sub-beams are collimated, and a combined laser beam is generated through a beam combiner; the combined laser beam in the first preset proportion range is coupled and input into the high-speed photoelectric detector for optical signal detection, an optical signal is converted into an electric signal, the electric signal is fed back to the phase algorithm controller for active on-chip phase adjustment, the brightness of the combined laser beam is greatly improved, and the structure is simple.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor laser technology, and in particular to a system and method for realizing coherent beam combining of a semiconductor laser array. Background Art

[0002] Compared with solid-state and fiber lasers, semiconductor lasers have the advantages of high electro-optical conversion efficiency, small size, high reliability and long life, and have important applications in industrial processing, military and optical communications. However, due to the limitations of its waveguide structure, the beam quality of semiconductor lasers in the fast and slow axis directions differs by dozens of times. For semiconductor laser arrays (such as standard bars), the beam quality in the slow axis direction differs by thousands of times, resulting in low brightness of the output laser beam, making it difficult to use as a direct light source. Therefore, how to obtain high-brightness semiconductor laser light sources for direct applications has become an international research frontier and academic hotspot.

[0003] Coherent beam combining technology is one of the most effective methods to improve the brightness of semiconductor lasers. It can use the coherent constructive method to superimpose the laser powers of multiple highly coherent and highly polarized laser sub-beams to obtain a high-brightness, narrow-linewidth direct semiconductor laser light source. Compared with laser beam combining technologies such as spectral beam combining and polarization beam combining, coherent beam combining can better maintain beam characteristics such as sub-beam linewidth and beam quality. At the same time, it can be combined with other laser beam combining methods for further beam combining, and has strong scalability. Whether it is near-field coherent beam combining or far-field coherent beam combining, the key technical difficulty of coherent beam combining lies in controlling the phase between array units so that the combined laser forms stable interference constructive phase, thereby improving the brightness of the combined laser beam. Active phase-locking technology has an advantage in the number of beam combining units and can obtain high-power coherent output. However, in the prior art, other phase-modulating optical devices are usually used to achieve phase locking between array units, which increases the complexity of the structure.

[0004] Therefore, the prior art needs to be further developed. Summary of the invention

[0005] The purpose of the present invention is to overcome the above technical deficiencies and provide a system and method for realizing coherent beam combining of semiconductor laser arrays to solve the problems existing in the prior art.

[0006] To achieve the above technical objectives, according to the first aspect of the present invention, the present invention provides a system for realizing coherent beam combining of a semiconductor laser array, the system comprising: a seed source, a collimator, a beam expander, a first beam splitter, a semiconductor laser array, a fast and slow axis collimator, a phase algorithm controller, a beam combiner, and a high-speed photodetector arranged in sequence along the laser transmission direction.

[0007] Specifically, the seed source is used to emit a laser beam, and the collimator is used to collimate the laser beam emitted by the seed source, so that the divergent laser beam becomes a parallel beam.

[0008] Specifically, the beam expander is used to increase the diameter of the collimated laser beam; The collimated laser beam passes through a beam expander and then a first beam splitter to split the laser beam into a plurality of sub-beams, and the plurality of sub-beams are coupled and input into a semiconductor laser array for optical signal amplification; The semiconductor laser array adopts a spatial linear arrangement of multiple light-emitting units.

[0009] Specifically, the system further comprises a fast-slow axis coupling mirror, which is arranged between the first beam splitter and the semiconductor laser array. The multiple sub-beams are coupled through the fast-slow axis coupling mirror and injected into the semiconductor laser array for optical signal amplification.

[0010] Specifically, the system further comprises a fast-slow axis collimator, which is arranged behind the semiconductor laser array and is used to collimate each sub-beam after the optical signal is amplified.

[0011] Specifically, the beam combiner is used to combine the collimated sub-beams to generate a combined laser beam, and the beam combining method includes flat aperture beam combining or filled aperture beam combining; The system also includes a transformation lens and a second beam splitter, wherein the transformation lens is arranged between the phase algorithm controller and the beam combiner, and the second beam splitter is arranged between the beam combiner and the high-speed photodetector. The second beam splitter splits the combined laser beam and inputs the combined laser beam within a first preset ratio range to the high-speed photodetector through the transformation lens.

[0012] Specifically, the high-speed photodetector is used to detect the received optical signal of the combined laser beam within a first preset ratio range, convert the optical signal into an electrical signal, and then feed the electrical signal back to the phase algorithm controller.

[0013] Specifically, the phase algorithm controller is used to actively perform on-chip phase modulation on each sub-beam amplified by the semiconductor laser array and collimated by the fast and slow axis collimator according to the electrical signal fed back by the received high-speed photodetector.

[0014] According to a second aspect of the present invention, there is provided a method for realizing coherent beam combining of a semiconductor laser array, comprising: S100, the laser beam emitted by the seed source is collimated by a collimator, the diameter of the laser beam is enlarged by a beam expander, and then the laser beam is divided into multiple sub-beams by a first beam splitter; S200, coupling the multiple sub-beams through fast-slow axis coupling mirrors and inputting them into a semiconductor laser array for optical signal amplification; S300, collimating each amplified sub-beam by using a fast-slow axis coupling mirror, and passing each collimated sub-beam through a beam combiner to generate a combined laser beam; S400, coupling the combined laser beam within a first preset ratio range to a high-speed photodetector for optical signal detection, and converting the optical signal into an electrical signal; S500 , feeding back the electrical signal to a phase algorithm controller to perform active on-chip phase modulation.

[0015] Specifically, the step of generating a combined laser beam by using a beam combiner to collimate each sub-beam includes: The collimated sub-beams are combined by a beam combiner through a flat aperture combination or a filled aperture combination to generate a combined laser beam.

[0016] Beneficial effects: The present invention utilizes a phase algorithm controller to perform active on-chip phase modulation, and realizes phase locking between array units by directly regulating the electrical signal loaded on the semiconductor laser array, so that the combined laser beam forms stable constructive interference, which greatly improves the brightness of the combined laser beam, and does not require additional optical elements. It has higher integration characteristics, has advantages in the number of beam combining units and miniaturization, and can obtain a semiconductor laser coherent light source with a simple and compact structure, which is more conducive to the realization of a small-volume, high-brightness semiconductor laser integrated light source, and provides a new path for the coherent synthesis of semiconductor lasers. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of a semiconductor laser coherent beam combining structure based on on-chip phase modulation provided in a specific embodiment of the present invention; Figure 2 It is a top view schematic diagram of a coherent beam combining structure based on a microlens array coupled magnifying array unit filling aperture provided in a specific embodiment of the present invention; Figure 3 It is a side view schematic diagram of a coherent beam combining structure based on a microlens array coupled magnifying array unit filling aperture provided in a specific embodiment of the present invention; Figure 4 It is a top view schematic diagram of a tiled aperture coherent beam combining structure based on a microlens array coupled magnifying array unit provided in a specific embodiment of the present invention; Figure 5 It is a side view schematic diagram of a tiled aperture coherent beam combining structure based on a microlens array coupled magnifying array unit provided in a specific embodiment of the present invention; Figure 6It is a top view schematic diagram of a coherent beam combining structure based on a DOE beam splitting coupling amplification array unit filling aperture provided in a specific embodiment of the present invention; Figure 7 It is a side view schematic diagram of a coherent beam combining structure based on a DOE beam splitting coupling amplification array unit filling aperture provided in a specific embodiment of the present invention; Figure 8 It is a schematic structural diagram of coherence and polarization mixing and beam combining of a semiconductor laser array unit provided in a specific embodiment of the present invention; Fig. 9 is a schematic diagram of output power stability with and without phase control provided in a specific embodiment of the present invention; Fig.10 is a flow chart of a method for realizing coherent beam combining of a semiconductor laser array provided in a specific embodiment of the present invention; Wherein, the reference numerals of the above-mentioned drawings are as follows: 1. Seed source; 2. Collimator; 3. Beam expander; 4. First beam splitter; 5. Fast and slow axis coupling mirror; 6. Semiconductor laser array; 7. Fast and slow axis collimator; 8. Phase algorithm controller; 9. High-speed photodetector; 10. Transformation lens; 11. Total reflection mirror; 12. Beam combiner; 13. Beam splitter prism; 15. Half-wave plate; 16. Second beam splitter. DETAILED DESCRIPTION In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is clearly and completely described below in conjunction with the accompanying drawings of the present invention. Based on the embodiments in this application, other similar embodiments obtained by ordinary technicians in this field without making creative work should all fall within the scope of protection of this application. In addition, the directional words mentioned in the following embodiments, such as "up", "down", "left", "right", etc., are only reference to the directions of the accompanying drawings. Therefore, the directional words used are used to illustrate rather than limit the invention.

[0018] The present invention will be further described below in conjunction with the accompanying drawings and preferred embodiments.

[0019] See also Figure 1-Figure 8 This embodiment provides a system for realizing coherent beam combining of a semiconductor laser array, the system comprising: a seed source 1, a collimator 2, a beam expander 3, a first beam splitter 4, a semiconductor laser array 6, a fast-slow axis collimator 7, a phase algorithm controller 8, a beam combiner 12, and a high-speed photodetector 9, which are arranged in sequence along the laser transmission direction.

[0020] Furthermore, the main operation process of the system for realizing coherent beam combining of semiconductor laser arrays in this embodiment includes: the collimated seed source 1 is divided into several sub-beams by the first beam splitter 4, and each sub-beam is coupled and injected into the semiconductor laser array 6 respectively to obtain a coherent array beam. Due to the phase mismatch caused by thermal and acousto-optic noise, that is, Δψ≠0, the phase algorithm controller 8 is used to perform active on-chip phase adjustment to ensure efficient phase locking between the parallel MOPA array unit laser beams, forming a stable coherent beam combination, thereby improving the brightness of the output laser beam.

[0021] Specifically, the seed source 1 is used to emit a laser beam, and the collimator 2 is used to collimate the laser beam emitted by the seed source 1 to convert the divergent laser beam into a parallel beam.

[0022] In some specific embodiments, the seed source 1 should have a narrower line width, lower intensity noise and phase noise, and the selected seed sources include but are not limited to DFB semiconductor laser seed sources, DBR semiconductor laser seed sources and fiber laser seed sources.

[0023] Specifically, the beam expander 3 is used to increase the diameter of the collimated laser beam; After the collimated laser beam passes through the beam expander 3, it passes through the first beam splitter 4 to split the laser beam into multiple sub-beams, and the multiple sub-beams are coupled and input into the semiconductor laser array 6 for optical signal amplification; The semiconductor laser array 6 adopts a spatial linear arrangement of multiple light emitting units.

[0024] In some specific embodiments, the seed source 1 is expanded by the beam expander 3 and then divided into several sub-beams by the beam splitter and coupled and injected into the corresponding semiconductor laser single array 6 for amplification. The laser beam wavefront can be directly divided into many tiny parts in space by a microlens array and coupled and injected into the semiconductor laser. A beam splitter can also be selected. The beam splitter can be a fiber beam splitter, a diffractive optical element (DOE), etc. The semiconductor laser array 6 used for coherent beam combining is a spatial linear arrangement of multiple light-emitting units, including but not limited to standard CM bar bars, Mini bar bars, or a linear array or stacked array of a single SOA and SOA-bar bars arranged in space.

[0025] Specifically, the system further includes a fast-slow axis coupling mirror 5, which is disposed between the first beam splitter 4 and the semiconductor laser array 6. The multiple sub-beams are coupled through the fast-slow axis coupling mirror 5 and injected into the semiconductor laser array 6 for optical signal amplification.

[0026] It should be further explained that in order to eliminate the influence of parasitic resonance effects on phase locking, the front and rear cavities of the semiconductor laser unit or array used for beam combining need to be subjected to anti-reflection treatment so that the reflectivity of the front and rear cavity surfaces is less than 0.1%. The semiconductor laser unit or array with anti-reflection in the front and rear cavities can be equivalently regarded as a semiconductor optical amplifier (SOA) unit or array.

[0027] Specifically, the system further comprises a fast-slow axis collimator 7, which is arranged behind the semiconductor laser array 6 and is used to collimate each sub-beam after the optical signal is amplified.

[0028] Specifically, the beam combiner 12 is used to combine the collimated sub-beams to generate a combined laser beam, and the beam combining method includes flat aperture beam combining or filled aperture beam combining; The system also includes a transformation lens 10 and a second beam splitter 16. The transformation lens 10 is arranged between the phase algorithm controller 8 and the beam combiner 12. The second beam splitter 16 is arranged between the beam combiner and the high-speed photodetector 9. The second beam splitter 16 splits the combined laser beam and inputs the combined laser beam within a first preset ratio range to the high-speed photodetector 9 through the transformation lens 10.

[0029] Specifically, the high-speed photodetector 9 is used to detect the received optical signal of the combined laser beam within the first preset ratio range, convert the optical signal into an electrical signal, and then feed the electrical signal back to the phase algorithm controller 8 .

[0030] Specifically, the phase algorithm controller 8 is used to actively perform on-chip phase modulation on each sub-beam amplified by the semiconductor laser array 6 and collimated by the fast and slow axis collimator 7 according to the electrical signal fed back by the received high-speed photodetector 9.

[0031] It can be understood that phase control uses phase detection and control of the load current of the beam combining unit to compensate for the phase jitter between the beam combining units. The selected phase algorithm controller 8 may include an analog / digital conversion module (ADC), a digital / analog conversion module (DAC), a voltage and current module, a high-speed acquisition card, an FPGA logic signal processing circuit, etc.; the phase algorithm controller 8 should have the characteristics of fewer algorithm iteration steps, fast convergence speed, and higher control bandwidth. The phase control algorithm can select a variety of phase control methods such as random parallel gradient descent (SPGD) algorithm, homodyne interference algorithm, multi-jitter algorithm, interference fringe extraction algorithm and artificial intelligence algorithm; the phase algorithm controller 8 quickly adjusts the phase modulator of the beam combining unit according to the signal of the high-speed photodetector 9 to achieve coherent phase-locked output. The high-speed photodetector 9 has the characteristics of DC-coupled output with high bandwidth, fast response time and better NEP (noise equivalent power) performance.

[0032] See also Figure 1-Figure 10 The working principle of this embodiment is described below through a specific example: The collimated seed source 1 is divided into several sub-beams of equal intensity after passing through the beam expander 3 and the first beam splitter 4. Each sub-beam is then injected into the semiconductor laser array 6 through the fast-slow axis coupling mirror 5 to appropriately amplify the power of the laser beam. The seed source 1 and the semiconductor laser array 6 constitute a master oscillator amplifier (MOPA) array unit with high coherence, and then output through the fast-slow axis collimator 7; The output array parallel light beam passes through the first beam splitter 4. Depending on the different ways of implementing the system aperture filling, most of the light is output by aperture coherent combining or common aperture coherent combining. A small part of the light passes through the transformation lens 10 and enters the high-speed photodetector 9 to achieve effective detection of the phase between the beam combining units. The phase is then fed back to the phase algorithm controller 8, which uses the on-chip phase modulation technology to regulate the current change loaded on the semiconductor laser array to accurately control the phase between the output beams of the array units to achieve phase locking, so that the combined laser beam forms stable constructive interference, thereby improving the brightness of the combined laser.

[0033] Figure 2-Figure 8 It is based on the on-chip phase modulation method to achieve coherent beam combining of different optical structures; It can be understood that, compared with the phase modulation method using additional optoelectronic devices, the phase modulation method proposed in the present invention has good integration characteristics, has advantages in the number of beam combining units and miniaturization, and can obtain a semiconductor laser coherent light source with a simple and compact structure.

[0034] It should be noted here that the present invention utilizes a phase algorithm controller to perform active on-chip phase modulation, and realizes phase locking between array units by directly regulating the electrical signal loaded on the semiconductor laser array, so that the combined laser beam forms stable constructive interference, which greatly improves the brightness of the combined laser beam, and does not require additional optical elements. It has higher integration characteristics, has advantages in the number of combining units and miniaturization, and can obtain a semiconductor laser coherent light source with a simple and compact structure, which is more conducive to the realization of a small-volume, high-brightness semiconductor laser integrated light source, and provides a new path for the coherent synthesis of semiconductor lasers.

[0035] See also Fig.10 This embodiment provides a method for realizing coherent beam combining of a semiconductor laser array, the method comprising: S100, the laser beam emitted by the seed source 1 is collimated by the collimator 2, the diameter of the laser beam is enlarged by the beam expander 3, and then divided into multiple sub-beams by the first beam splitter 4; S200, coupling the multiple sub-beams through the fast-slow axis coupling mirror 5 and inputting them into the semiconductor laser array 6 for optical signal amplification; S300, collimating each amplified sub-beam by using a fast-slow axis coupling mirror 5, and passing each collimated sub-beam through a beam combiner 12 to generate a combined laser beam; S400, coupling the combined laser beam within the first preset ratio range to the high-speed photodetector 9 for optical signal detection, and converting the optical signal into an electrical signal; S500 , feeding back the electrical signal to the phase algorithm controller 8 to perform active on-chip phase modulation.

[0036] Specifically, the process of generating a combined laser beam by passing the collimated sub-beams through the beam combiner 12 includes: The beam combiner 12 is used to combine the collimated sub-beams by flat aperture combining or filled aperture combining to generate a combined laser beam.

[0037] See also Figure 2-Figure 5 In some specific embodiments, the phase-locked array unit can realize tiled aperture (TiledAperture) beam combining and filled aperture (FilledAperture) beam combining, and the beam combiner 12 can be used to realize high-efficiency, high-beam-quality coherent beam combining, such as Figure 6-Figure 7 As shown, the selected beam combiner 12 includes but is not limited to diffraction optical elements (DOE) such as Dammann gratings, polarization gratings and metasurfaces; in this embodiment, the first preset ratio range is set to 0.01~1%, and 0.01~1% of the combined laser beam is fed back to the high-speed photodetector 9 for phase detection and compensation, and the selected second beam splitter 16 includes but is not limited to a flat beam splitter and a diffraction beam splitter (beam sampling DOE).

[0038] See also Fig.10 The working principle of this embodiment is described below through a specific example: The coherent combination of semiconductor lasers can improve the output power while ensuring the laser output with high beam quality and narrow line width. In view of the current situation that the semiconductor laser coherent combination system has a complex structure and low integration, this embodiment proposes a method for realizing the coherent beam combination of semiconductor laser arrays and the coherent phase locking method between array units. The specific steps are as follows: (1) After the seed source 1 is expanded by the beam expander 3, it is divided into several sub-beams and respectively coupled and injected into the semiconductor laser array 6 for amplification. The seed source 1 and the semiconductor laser array 6 constitute a master oscillator amplifier (MOPA) array unit with high coherence; (2) The semiconductor laser array 6 units are packaged on a heat sink to form a linear array or a stacked array, and the fast axis and slow axis of the amplified laser beam are collimated using a fast and slow axis collimator 7; (3) Using the second beam splitter 16, 0.01-1% of the combined laser beam is coupled to the high-speed photodetector 9 for optical signal detection, and then the detection signal is fed back to the phase algorithm controller 8. The current change loaded on the semiconductor laser is regulated by the on-chip phase modulation technology to compensate for the phase difference between the output beams of the array units, so that the combined laser beam forms stable constructive interference; (4) After collimation, the laser beam array unit can realize flat aperture beam combining and filled aperture beam combining.

[0039] In the above process, the semiconductor lasers described in steps (1) and (2) include but are not limited to standard CM bars, Mini bars, or linear arrays or stacked arrays of emitters and bars arranged in space. In order to eliminate the influence of parasitic resonance effects on phase locking, the front and rear cavities of the semiconductor laser units or arrays used for beam combining need to be subjected to anti-reflection treatment so that the reflectivity of the front and rear cavity surfaces is less than 0.1%. The output spectral range can be selected according to usage requirements.

[0040] In the above process, in step (1), the seed source 1 needs to be coupled and injected into the corresponding semiconductor laser array 6 for amplification. The expanded laser beam can be directly coupled and injected into the semiconductor laser array 6 through a microlens array, or components such as an optical fiber beam splitter and a DOE beam splitter can be used to perform beam splitting coupling injection of the seed source.

[0041] In the above process, in step (2), the semiconductor laser array unit is packaged on a heat sink, which needs to meet the individual power supply requirements of the array units.

[0042] In the above process, the semiconductor laser chip used in the on-chip phase modulation technology in step (3) has a phase modulation function, and its phase modulation range reaches more than π; the high-speed photodetector 9 should have the characteristics of high bandwidth, fast response time and better NEP (noise equivalent power) performance of DC coupled output; the phase algorithm controller 8 should have the characteristics of small algorithm iteration steps, fast convergence speed and high control bandwidth; the beam splitting sampling ratio is selected according to the response parameters of the photodetector used.

[0043] In the above process, if the filled aperture beam combining method is selected in step (4), the beam combiner 12 can be used to achieve common aperture beam combining; if the tiled aperture beam combining method is selected, it is required to increase the filling factor of the entire column of units as much as possible. Therefore, it is necessary to perform certain beam shaping after the semiconductor laser array unit is amplified and collimated. Improving the filling factor can make the beam after the tiled aperture beam combining more compact in space and more uniform in energy distribution, which is very critical for application scenarios that require large-area uniform illumination or need to improve beam coupling efficiency.

[0044] like Fig. 9 As shown, Fig. 9It represents the stability of the output power without phase control, that is, the output signal (optical signal converted into electrical signal) of the split light detection before and after the beam synthesis (open loop). Fig. 9 It can be seen that after the loop is closed, a coherent light beam is output and the synthesized light beam is stable, which further proves that the present invention can make the combined laser beam form stable constructive interference and greatly improve the brightness of the combined laser beam.

[0045] It should be noted here that the present invention utilizes a phase algorithm controller to perform active on-chip phase modulation, and realizes phase locking between array units by directly regulating the electrical signal loaded on the semiconductor laser array, so that the combined laser beam forms stable constructive interference, which greatly improves the brightness of the combined laser beam, and does not require additional optical elements. It has higher integration characteristics, has advantages in the number of combining units and miniaturization, and can obtain a semiconductor laser coherent light source with a simple and compact structure, which is more conducive to the realization of a small-volume, high-brightness semiconductor laser integrated light source, and provides a new path for the coherent synthesis of semiconductor lasers.

[0046] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0047] The various technical features described above can be combined arbitrarily. Although all possible combinations of these technical features are not described, any combination of these technical features should be considered to be covered by this specification as long as there is no contradiction in such combination.

[0048] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A system for realizing coherent beam combining of semiconductor laser arrays, characterized in that: The system comprises: a seed source (1), a collimator (2), a beam expander (3), a first beam splitter (4), a semiconductor laser array (6), a fast-slow axis collimator (7), a phase algorithm controller (8), a beam combiner (12), and a high-speed photodetector (9) which are sequentially arranged along a laser transmission direction.

2. The system for realizing coherent beam combining of semiconductor laser arrays according to claim 1, characterized in that: The seed source (1) is used to emit a laser beam, and the collimator (2) is used to collimate the laser beam emitted by the seed source (1) so as to convert the divergent laser beam into a parallel beam.

3. The system for realizing coherent beam combining of semiconductor laser arrays according to claim 2, characterized in that: The beam expander (3) is used to increase the diameter of the collimated laser beam; The collimated laser beam passes through a beam expander (3) and then passes through a first beam splitter (4) to split the laser beam into a plurality of sub-beams, and the plurality of sub-beams are coupled and input into a semiconductor laser array (6) for optical signal amplification; The semiconductor laser array (6) adopts a spatial linear arrangement of multiple light-emitting units.

4. The system for realizing coherent beam combining of semiconductor laser arrays according to claim 3, characterized in that: The system further comprises a fast-slow axis coupling mirror (5), wherein the fast-slow axis coupling mirror (5) is arranged between the first beam splitter (4) and the semiconductor laser array (6), and the plurality of sub-beams are coupled through the fast-slow axis coupling mirror (5) and injected into the semiconductor laser array (6) for optical signal amplification.

5. The system for realizing coherent beam combining of semiconductor laser arrays according to claim 4, characterized in that: The system further comprises a fast-slow axis collimator (7), which is arranged behind the semiconductor laser array (6) and is used to collimate each sub-beam after the optical signal is amplified.

6. The system for realizing coherent beam combining of semiconductor laser arrays according to claim 5, characterized in that: The beam combiner (12) is used to combine the collimated sub-beams to generate a combined laser beam, and the beam combining method includes flat aperture beam combining or filled aperture beam combining; The system further comprises a transforming lens (10) and a second beam splitter (16), wherein the transforming lens (10) is arranged between the phase algorithm controller (8) and the beam combiner (12), and the second beam splitter (16) is arranged between the beam combiner and the high-speed photodetector (9), and the second beam splitter (16) splits the combined laser beam and inputs the combined laser beam within a first preset ratio range to the high-speed photodetector (9) via the transforming lens (10).

7. The system for realizing coherent beam combining of semiconductor laser arrays according to claim 6, characterized in that: The high-speed photoelectric detector (9) is used to detect the received optical signal of the combined laser beam within a first preset ratio range, convert the optical signal into an electrical signal, and then feed the electrical signal back to the phase algorithm controller (8).

8. The system for realizing coherent beam combining of semiconductor laser arrays according to claim 7, characterized in that: The phase algorithm controller (8) is used to actively perform on-chip phase modulation on each sub-beam after being amplified by the semiconductor laser array (6) and collimated by the fast and slow axis collimator (7) according to the electrical signal fed back by the received high-speed photodetector (9).

9. A method for realizing coherent beam combining of a semiconductor laser array, characterized in that: include: S100, the laser beam emitted by the seed source (1) is collimated by a collimator (2), the diameter of the laser beam is enlarged by a beam expander (3), and then the laser beam is split into a plurality of sub-beams by a first beam splitter (4); S200, coupling the plurality of sub-beams through the fast-slow axis coupling mirror (5) and inputting them into the semiconductor laser array (6) for optical signal amplification; S300, using a fast-slow axis coupling mirror (5) to collimate each amplified sub-beam, and passing each collimated sub-beam through a beam combiner (12) to generate a combined laser beam; S400, coupling the combined laser beam within a first preset ratio range to a high-speed photodetector (9) for optical signal detection, and converting the optical signal into an electrical signal; S500, feeding back the electrical signal to the phase algorithm controller (8) to perform active on-chip phase modulation.

10. The method for realizing coherent beam combining of semiconductor laser arrays according to claim 9, characterized in that: The step of generating a combined laser beam by passing the collimated sub-beams through a beam combiner (12) comprises: The beam combiner (12) combines the collimated sub-beams by means of flat aperture beam combining or filled aperture beam combining to generate a combined laser beam.

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