Polarization and spectrum combined laser synthesis system and method thereof

Abstract

The invention provides a polarization and spectrum combined laser synthesis system and method, and belongs to the field of laser beam synthesis, and the system comprises a laser seed source, an optical fiber beam splitting module, a phase control module, an optical fiber output module, a two-dimensional polarization coherent beam combination module and a dispersion element which are connected in sequence; the two-dimensional polarization coherent beam combination module is of a spatial three-dimensional structure; the number of the laser seed sources is m, the laser seed sources are arranged in parallel, each laser seed source corresponds to one optical fiber beam splitting module, and laser emitted by each laser seed source is divided into 2n sub-beams which have the same wavelength and are parallel to each other through the optical fiber beam splitting module, the 2n sub light beams respectively correspond to 2n phase control modules, 2n optical fiber output modules and the same two-dimensional polarization coherent beam combining module; the 2n sub-light beams are coherently combined into the same laser beam, and the m laser spectrums with different wavelengths are combined to obtain the high-power laser. According to the invention, high-power laser is synthesized by using the integrated light beam synthesis system.

Description

Technical Field

[0001] The present invention relates to the technical field of laser beam synthesis, and in particular to a polarization and spectrum combined laser synthesis system and method thereof. Background Art

[0002] At present, an effective way to increase the output power of lasers is to superimpose the power of multiple fiber lasers through a beam synthesis element to obtain a high-power synthetic beam. Polarization coherent synthesis technology and spectrum synthesis technology are effective ways to build high-power, high-brightness laser light sources. Polarization coherent synthesis technology mainly uses the phase characteristics of lasers to coherently synthesize multiple lasers of the same wavelength. Spectral synthesis technology mainly uses the spectral characteristics of lasers to spectrally synthesize multiple lasers of different wavelengths. If the two methods are combined for composite beam synthesis, the output power of the synthesized beam will be further improved.

[0003] During polarization coherent synthesis, two laser beams first pass through a polarization beam combining element to achieve primary polarization synthesis, and as a sub-beam for secondary polarization synthesis, they pass through another polarization beam combining element for the next synthesis, and so on, until a single laser output is completed. At present, when performing polarization coherent synthesis, the incident angle of the light beam incident on the polarization beam combining element is not restricted, and the polarization coherent element is a planar structure (i.e., a one-dimensional element). As the number of optical paths increases, in order to achieve polarization coherent synthesis, the plane of the planar polarization coherent element must be infinitely extended, thereby occupying a large space, which undoubtedly limits the synthesis of high-power lasers. Summary of the invention

[0004] In view of the technical problems existing in the background technology, the present application provides a polarization and spectrum combined laser synthesis system and method thereof, aiming to solve the technical problems that planar polarization coherent elements occupy a large space and limit high-power laser synthesis.

[0005] In a first aspect, an embodiment of the present application provides a laser synthesis system combining polarization and spectrum, comprising a laser seed source, an optical fiber splitting module, a phase control module, an optical fiber output module, a two-dimensional polarization coherent beam combining module and a dispersion element connected in sequence; the two-dimensional polarization coherent beam combining module is a spatial three-dimensional structure; the number of the laser seed sources is m and they are arranged in parallel, each of the laser seed sources corresponds to one optical fiber splitting module, and the laser emitted by each of the laser seed sources is divided into two by the optical fiber splitting module. n sub-beams of the same wavelength and parallel to each other, 2 n The sub-beams of the same wavelength correspond to 2 n the phase control module, 2 n The optical fiber output module and the same two-dimensional polarization coherent beam combining module; 2 nThe fiber optic output module outputs 2 n The sub-beams are coherently combined into the same laser beam by the two-dimensional polarization coherent beam combining module, and the m laser beams with different wavelengths output by the m two-dimensional polarization coherent beam combining modules are spectrally combined by the dispersion element to obtain high-power laser.

[0006] In the technical solution of the embodiment of the present application, the two-dimensional polarization coherent beam combining module is arranged into a spatial three-dimensional structure, and at the same time, by strictly controlling the direction of the light beam incident to the two-dimensional polarization coherent beam combining module, the synthesis of high-power laser is achieved in a smaller occupied space.

[0007] In some embodiments, n is an integer greater than or equal to 2.

[0008] In this embodiment, the number of coherent lights incident on the two-dimensional polarization coherent beam combining module is controlled by controlling the value range of n, and the coherent combination of multiple light beams is achieved by coordinating the specific spatial structure of the two-dimensional polarization coherent beam combining module.

[0009] In some embodiments, the two-dimensional polarization coherent beam combining module comprises 2 n -1 beam combining assembly with polarization beam combining function is stacked in space;

[0010] When n=2, the two-dimensional polarization coherent beam combining module includes three beam combining components, and the three beam combining components are stacked in an L shape; the sub-beams entering the two-dimensional polarization coherent beam combining module are arranged in a 2×2 structure, and the 2×2 sub-beams are incident in parallel on the same plane of the L shape;

[0011] When n≥3, the structure of the two-dimensional polarization coherent beam combining module is flipped with the two-dimensional polarization coherent beam combining module corresponding to n-1 as a structural unit to obtain a mirror-symmetrical structure, and an additional beam combining component is added.

[0012] In this embodiment, according to the specific number of light beams incident into the two-dimensional polarization coherent beam combining module, the two-dimensional polarization coherent beam combining module is arranged into a corresponding spatial structure, and the arrangement and incident angle of the light beams incident into the two-dimensional polarization coherent beam combining module are strictly controlled, so that the coherent synthesis of multiple light beams is achieved through the two-dimensional polarization coherent beam combining module with a compact spatial structure.

[0013] In some embodiments, the beam combining component is an integrated body formed by a half-wave plate, a polarization beam combining element and a reflector.

[0014] In this embodiment, by configuring the beam combining component as an integrated body formed by a half-wave plate, a polarization beam combining element and a reflector, on the one hand, the beam combining component is integrated, thereby making the two-dimensional polarization coherent beam combining module compact; on the other hand, the incident angle of the incident light entering the two-dimensional polarization coherent beam combining module can be more conveniently controlled.

[0015] In some embodiments, when n=2, two of the three beam combining assemblies are stacked up and down, and the other one is placed vertically to form an L-shaped structure.

[0016] In this embodiment, by arranging the three beam combining components in a specific manner, the structure of the two-dimensional polarization coherent beam combining module is regularized and integrated; thereby, the corresponding two-dimensional polarization coherent beam combining module is more integrated when n≥3.

[0017] In some embodiments, the polarization beam combining element is a polarization beam combining prism or a birefringent crystal; the reflector is a 45° reflector; the rotation angle θ of the half-wave plate and the powers P1 and P2 of the two sub-beams incident on the corresponding beam combining component satisfy tanθ=P1 / P2.

[0018] In some embodiments, an optical fiber amplifier is provided between the phase control module and the optical fiber output module, m×2 n Each optical fiber amplifier is provided in the optical path of each light beam.

[0019] In this embodiment, by setting an optical fiber amplifier, the n The power of the beam sub-beam is increased, thereby increasing the power of the final laser.

[0020] In some embodiments, the phase control module includes a phase controller and an FPGA phase control platform.

[0021] In some embodiments, the fiber optic output module is an output end cap.

[0022] In the second aspect, the embodiment of the present application provides a laser synthesis method combining polarization and spectrum, using the laser synthesis system combining polarization and spectrum described above, the lasers output by m laser seed sources are respectively passed through m optical fiber splitting modules, and each optical fiber splitting module splits the input laser into two n A sub-beam of the same wavelength, 2 n The sub-beams of the same wavelength are outputted through the corresponding phase control module and the optical fiber output module respectively, and are coherently combined into the same laser beam through the two-dimensional polarization coherent beam combining module. The m beams of laser beams with different wavelengths outputted by the m two-dimensional polarization coherent beam combining modules are spectrally combined by the dispersion element to obtain a high-power laser.

[0023] In the technical solution of the embodiment of the present application, the synthesis of high-power light beams is achieved by utilizing a more integrated polarization and spectrum combined laser synthesis system.

[0024] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings used in the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a schematic diagram of the structure of a laser synthesis system combining polarization and spectrum in an embodiment of the present application;

[0027] Figure 2 a is an exploded view of a two-dimensional polarization coherent beam combining module when n=2 in an embodiment of the present application; Figure 2 b is a schematic diagram of the structure of a two-dimensional polarization coherent beam combining module when n=2 in an embodiment of the present application;

[0028] Figure 3 a is a diagram of the arrangement of light beams incident on the two-dimensional polarization coherent beam combining module when n=2 in the embodiment of the present application; Figure 3 b is a schematic diagram of the optical path structure of the incident and output two-dimensional polarization coherent beam combining module when n=2 in the embodiment of the present application;

[0029] Figure 4 a is Figure 3 a is a top view of the optical paths of sub-beams 1-1 and 1-2 in the beam combining assembly; Figure 4 b is Figure 3 a is a top view of the optical paths of the sub-beam 2-1 and the sub-beam 2-2 in the beam combining assembly; Figure 4 c is Figure 3 a is a cross-sectional view of the optical path in the beam combining assembly placed along the vertical direction; Figure 4 d is Figure 3 a is a stereogram of the optical path of the two-dimensional polarization coherent beam combining module;

[0030] Figure 5 a is an exploded view of a two-dimensional polarization coherent beam combining module when n=3 in an embodiment of the present application; Figure 5 b is a schematic diagram of the structure of a two-dimensional polarization coherent beam combining module when n=3 in an embodiment of the present application;

[0031] Figure 6 a is an exploded view of a two-dimensional polarization coherent beam combining module when n=4 in an embodiment of the present application; Figure 6b is a schematic diagram of the structure of a two-dimensional polarization coherent beam combining module when n=4 in an embodiment of the present application;

[0032] Figure 7 Schematic diagram of the structure of the laser synthesis system of polarization and spectrum combination when m=2 and n=4 in the embodiment of the present application.

[0033] Explanation of the reference numerals: 1000 - polarization and spectrum combined laser synthesis system; 1 - laser seed source; 2 - optical fiber splitting module; 3 - phase control module; 4 - optical fiber amplifier; 5 - optical fiber output module; 6 - two-dimensional polarization coherent beam combining module; 7 - dispersion element; 61 - beam combining component; 62 - half-wave plate; 63 - polarization beam combining element; 64 - reflector. DETAILED DESCRIPTION

[0034] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0035] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0036] The term "comprising" herein indicates the presence of the described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections. The terms "comprising", "including", "having" and their variations all mean "including but not limited to", excluding that they are specially emphasized in other ways. Hereinafter, the terms "first" and "second" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating one or more of the features. In the description of the embodiments of the present application, unless otherwise stated, the meaning of "multiple" is two or more.

[0037] In this article, the term "and / or" is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0038] Improving laser power has always been a concern of people. One of the reasons limiting the synthesis of high-power lasers is that the structure of existing planar polarization coherent elements occupies a large area. Therefore, how to synthesize high-power lasers through an integrated system is particularly important.

[0039] In order to solve the technical problem that planar polarization coherent elements occupy a large space and limit high-power laser synthesis, the present application provides a laser synthesis system and method combining polarization and spectrum, wherein, by arranging the two-dimensional polarization coherent beam combining module into a neat and integrated spatial three-dimensional structure, and by strictly controlling the direction of the light beam incident to the two-dimensional polarization coherent beam combining module, under the synergistic effect of the beam arrangement mode, the beam incident direction and the two-dimensional polarization coherent beam combining module of a specific structure, a three-dimensionally arranged polarization coherent beam combining optical path is obtained, and used as a sub-beam for spectral synthesis, and by effectively combining polarization coherent synthesis with spectral synthesis, high-power laser synthesis is achieved. The present application has good application value for improving the number of paths, power, stability of beam synthesis, and improving the integration and miniaturization of the system.

[0040] For the convenience of description, the following embodiments are described by taking a polarization and spectrum combined laser synthesis system 1000 according to an embodiment of the present application as an example.

[0041] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a laser synthesis system 1000 combining polarization and spectrum provided in some embodiments of the present application. The laser synthesis system 1000 combining polarization and spectrum includes a laser seed source 1, a fiber splitting module 2, a phase control module 3, a fiber output module 5, a two-dimensional polarization coherent beam combining module 6, and a dispersion element 7 connected in sequence; the two-dimensional polarization coherent beam combining module 6 is a spatial three-dimensional structure; the number of laser seed sources 1 is m and they are arranged in parallel, each laser seed source corresponds to a fiber splitting module 2, and the laser emitted by each laser seed source 1 is divided into two by the fiber splitting module 2. n sub-beams of the same wavelength and parallel to each other, 2 n The sub-beams of the same wavelength correspond to 2 n Phase control modules 3, 2 n A fiber output module 5 and a two-dimensional polarization coherent beam combining module 6; 2 n Fiber Optic Output Module 5 Outputs 2 n The sub-beams are coherently combined into the same laser beam by the two-dimensional polarization coherent beam combining module 6, and the m beams of laser light with different wavelengths output by the m two-dimensional polarization coherent beam combining modules 6 are spectrally combined by the dispersion element 7 to obtain a high-power laser.

[0042] Furthermore, in the embodiment of the present application, n is an integer greater than or equal to 2. In this embodiment, by controlling the value range of n, the number of coherent lights incident into the two-dimensional polarization coherent beam combining module 6 is controlled, and the coherent synthesis of multiple light beams is achieved in conjunction with the specific spatial structure of the two-dimensional polarization coherent beam combining module 6.

[0043] Further, in the embodiment of the present application, the structure of the two-dimensional polarization coherent beam combining module 6 matches the value of n. The two-dimensional polarization coherent beam combining module 6 consists of 2 n -1 beam combining components 61 with polarization beam combining function are stacked in space. Specifically, when n=2, please refer to Figure 2 The two-dimensional polarization coherent beam combining module includes three beam combining components 61, and the three beam combining components 61 are stacked in an L shape. Specifically, two of the three beam combining components 61 are stacked up and down, and the other is placed vertically to form an L-shaped structure. The two stacked beam combining components 61 are placed in the horizontal direction, and the other beam combining component 61 is placed in the vertical direction. Please refer to Figure 3 At this time, the sub-beams entering the two-dimensional polarization coherent beam combining module 6 are arranged in a 2×2 structure, and the 2×2 sub-beams (recorded as sub-beam 1-1, sub-beam 1-2, sub-beam 2-1, and sub-beam 2-2) are incident in parallel on the same plane of the L-shape, and the incident angle is 90°. In this embodiment, the three beam combining components 61 are arranged in a specific manner to form a structurally regular and integrated L-shaped two-dimensional polarization coherent beam combining module 6, and the incident angles of the 2×2 sub-beams on the two-dimensional polarization coherent beam combining module 6 are controlled at the same time, so that they are coherently combined and output in the two-dimensional polarization coherent beam combining module 6, and then spectrally combined through the dispersion element 7, and finally a high-power laser is obtained.

[0044] Further, in the embodiments of the present application, please refer to Figure 4 a and Figure 4 c, the beam combining component 61 is an integrated body formed by a half-wave plate 62, a polarization beam combining element 63 and a reflector 64. In this embodiment, by setting the beam combining component 61 as an integrated body formed by a half-wave plate 62, a polarization beam combining element 63 and a reflector 64, on the one hand, the beam combining component 61 is integrated, and then the structure of the two-dimensional polarization coherent beam combining module 6 is regularized and integrated, and on the other hand, the incident angle of the incident light incident into the two-dimensional polarization coherent beam combining module 6 can be more conveniently controlled, so that under the synergistic effect of the beam arrangement mode, the beam incident direction and the two-dimensional polarization coherent beam combining module with a specific structure, the synthesis of coherent light is achieved, and then the synthesis of high-power laser is achieved.

[0045] The polarization beam combining element 63 is a polarization beam combining prism or a birefringent crystal; the reflector 64 is a 45° reflector, the rotation angle θ of the half-wave plate 62 and the powers P1 and P2 of the two sub-beams incident into the corresponding beam combining component 61 satisfy tanθ=P1 / P2, the power of the sub-beam passing through the reflector 64 is P2, and the power of the sub-beam is adjusted by the optical fiber amplifier 4.

[0046] When n=2, the optical paths of the four coherent beams in the two-dimensional polarization coherent beam combining module 6 are shown in Figure 4 As shown, the half-wave plate 62 in this embodiment is a 45° half-wave plate. Sub-beams 1-1 and 1-2 are coherently combined into a first-order sub-beam 1-0 in the upper beam combining component 61 placed in the horizontal direction (sub-beam 1-1 is reflected by a 45° reflector 64 and reaches the polarization beam combining prism, and the transmitted light of sub-beam 1-2 is combined with the reflected light of sub-beam 1-1 in the polarization beam combining prism, and the common aperture output is realized), sub-beams 2-1 and 2-2 are coherently combined into a first-order sub-beam 2-0 in the lower beam combining component 61 placed in the horizontal direction (the optical path principle is the same as above), and the first-order sub-beams 1-0 and the first-order sub-beams 2-0 are coherently combined into a second-order sub-beam (i.e., a single laser) through the beam combining component 61 placed in the vertical direction, and are output from the two-dimensional polarization coherent beam combining module 6 (the optical path principle is the same as above), and then enter the dispersion element 7 for spectral synthesis.

[0047] Furthermore, in an embodiment of the present application, when n≥3, the structure of the two-dimensional polarization coherent beam combining module 6 is flipped with the two-dimensional polarization coherent beam combining module 6 corresponding to n-1 as a structural unit to obtain a mirror-symmetrical structure, and a beam combining component 61 is added. In this embodiment, according to the specific number of light beams incident into the two-dimensional polarization coherent beam combining module 6, the two-dimensional polarization coherent beam combining module 6 is set to a corresponding spatial structure, and the arrangement mode and incident angle of the light beams incident into the two-dimensional polarization coherent beam combining module 6 are strictly controlled, and the coherent synthesis of multiple light beams is achieved through the two-dimensional polarization coherent beam combining module with a compact spatial structure. When n=3, the structure of the two-dimensional polarization coherent beam combining module 6 refers to Figure 5 , that is, the L-shaped two-dimensional polarization coherent beam combining module 6 when n=2 is used as a structural unit to be flipped in the horizontal direction to obtain a mirror-symmetrical structure, and a beam combining component 61 is added along the forward direction of the optical path, and the beam combining component 61 is placed horizontally and is aligned with Figure 2The upper beam combining component 61 placed horizontally in the middle is located on the same horizontal plane. At this time, the arrangement mode of the light beams entering the two-dimensional polarization coherent beam combining module 6, the incident angle of the light beams, and the optical path are also flipped and symmetrically processed accordingly. It is worth noting that in another embodiment, when n=3, the structure of the two-dimensional polarization coherent beam combining module 6 is flipped in the vertical direction with the L-type two-dimensional polarization coherent beam combining module 6 when n=2 as the structural unit to obtain a mirror-symmetrical structure, and a beam combining component 61 is added along the forward direction of the optical path. At this time, the structure of the two-dimensional polarization coherent beam combining module 6 is obtained by turning Figure 5 The structure of b is flipped 90°.

[0048] When n=4, the structure of the two-dimensional polarization coherent beam combining module 6 is as follows: Figure 6 That is, the L-shaped two-dimensional polarization coherent beam combining module 6 when n=3 is used as a structural unit to be flipped in the vertical direction to obtain a mirror-symmetrical structure, and a beam combining component 61 is added along the direction of the optical path, and the beam combining component 61 is placed vertically (the specific placement direction and position of the beam combining component 61 are changed accordingly according to the incident position of the previous stage sub-beam). At this time, the arrangement mode of the light beams entering the two-dimensional polarization coherent beam combining module 6, the beam incident angle and the optical path are also flipped and symmetrically processed accordingly. It is worth noting that in another embodiment, when n=4, the structure of the two-dimensional polarization coherent beam combining module 6 is flipped in the horizontal direction with the two-dimensional polarization coherent beam combining module 6 when n=3 as a structural unit to obtain a mirror-symmetrical structure, and a beam combining component 61 is added along the direction of the optical path.

[0049] As n increases, the structure of the corresponding two-dimensional polarization coherent beam combining module 6 is similar and will not be described in detail here.

[0050] It can be seen that the present application adopts a two-dimensional polarization coherent beam combining module 6 with a spatial stereoscopic structure, so that the sub-beams incident to the two-dimensional polarization coherent beam combining module 6 are arranged in a stereoscopic manner and undergo stereoscopic polarization synthesis, while m beams of lasers of different wavelengths are arranged in a stereoscopic manner and undergo stereoscopic spectral synthesis. Compared with the traditional planar arrangement polarization synthesis, the scalability of the laser path is greatly improved, and high-power laser output is achieved while maintaining the miniaturization and compactness of the system. The present application adopts a modular two-dimensional polarization coherent beam combining module 6 for polarization coherent synthesis, which can not only reduce the difficulty of optical path construction and save optical path construction time, but also improve the stability of the light source through a modular structure.

[0051] Furthermore, in the embodiment of the present application, an optical fiber amplifier 4 is provided between the phase control module 3 and the optical fiber output module 5, m×2 n Each optical path of the light beam is provided with an optical fiber amplifier 4. In this embodiment, the optical fiber amplifier 4 is provided to n The light beam is amplified to increase the power of each sub-beam, thereby increasing the power of the final laser.

[0052] Further, in the embodiment of the present application, the phase control module 3 includes a phase controller and an FPGA phase control platform. In some embodiments, a beam splitter (not shown in the figure) is provided between the two-dimensional polarization coherent beam combining module 6 and the dispersion element 7, and a small portion of the light is reflected by the beam splitter to the phase control module 3 and received by the phase control module 3 as a feedback signal; most of the light is transmitted along the main optical path.

[0053] Furthermore, in the embodiment of the present application, the optical fiber output module 5 is an output end cap.

[0054] Further, in the embodiments of the present application, please refer to Figure 7 , a laser synthesis system 1000 combining polarization and spectrum is provided. The laser synthesis system 1000 combining polarization and spectrum comprises a laser seed source 1, a fiber splitting module 2, a phase control module 3, a fiber amplifier 4, a fiber output module 5, a two-dimensional polarization coherent beam combining module 6 and a dispersion element 7 connected in sequence; the two-dimensional polarization coherent beam combining module 6 is a spatial three-dimensional structure; the number of laser seed sources 1 is 2 and they are arranged in parallel, and the wavelengths of the two laser seed sources 1 are 1064nm and 1066nm respectively. Each laser seed source corresponds to a fiber splitting module 2, and the laser emitted by each laser seed source 1 is divided into 4 (n=2 at this time, the two-dimensional polarization coherent beam combining module 6 is an L-shaped structure) sub-beams of the same wavelength and parallel to each other through the fiber splitting module 2, and the 4 sub-beams of the same wavelength correspond to 4 phase control modules 3, 4 fiber amplifiers 4, 4 fiber output modules 5 and the same two-dimensional polarization coherent beam combining module 6; the lasers output by the two laser seed sources 1 are respectively divided into 4 sub-beams of the same wavelength through the two fiber splitting modules 2. The four sub-beams of the same wavelength are phase-synchronized by the corresponding phase control modules 3 to obtain four coherent lights, and the four coherent lights are amplified by four fiber amplifiers 4 with equal power, and output from four corresponding fiber output modules 5, and then coherently combined into the same laser beam by the same two-dimensional polarization coherent beam combining module 6. The two laser beams of different wavelengths (i.e., λ1 and λ2) output by the two two-dimensional polarization coherent beam combining modules 6 are simultaneously converged on the dispersion element 7 at different incident angles, and are spectrally combined by the dispersion element 7 to obtain high-power laser. In this embodiment, the polarization beam combining element 63 is a polarization beam combining prism; the reflector 64 is a 45° reflector, and the half-wave plate 62 is a 45° half-wave plate.

[0055] In the second aspect, the embodiment of the present application provides a laser synthesis method combining polarization and spectrum, using the above-mentioned laser synthesis system combining polarization and spectrum, the lasers output by m laser seed sources 1 are respectively passed through m optical fiber splitting modules 2, and each optical fiber splitting module 2 splits the input laser into 2 n A sub-beam of the same wavelength, 2 nThe sub-beams of the same wavelength are outputted through the corresponding phase control module 3 and the optical fiber output module 5 respectively, and are coherently combined into the same laser beam through the same two-dimensional polarization coherent beam combining module 6. The m beams of lasers with different wavelengths outputted by the m two-dimensional polarization coherent beam combining modules 6 are simultaneously converged on the dispersion element 7 at different incident angles, and are spectrally combined by the dispersion element 7 to obtain a high-power laser.

[0056] In the technical solution of the embodiment of the present application, under the synergistic effect of the beam arrangement method incident to the two-dimensional polarization coherent beam combining module, the beam incident direction and the two-dimensional polarization coherent beam combining module with a specific structure, a more integrated polarization and spectral combined laser synthesis system is used to achieve high-power beam synthesis.

[0057] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A laser synthesis system combining polarization and spectrum, characterized in that: The invention comprises a laser seed source, an optical fiber beam splitting module, a phase control module, an optical fiber output module, a two-dimensional polarization coherent beam combining module and a dispersion element which are connected in sequence; the two-dimensional polarization coherent beam combining module is a spatial three-dimensional structure; the number of the laser seed sources is m and they are arranged in parallel, each of the laser seed sources corresponds to one optical fiber beam splitting module, and the laser emitted by each laser seed source is divided into two by the optical fiber beam splitting module. n sub-beams of the same wavelength and parallel to each other, 2 n The sub-beams of the same wavelength correspond to 2 n the phase control module, 2 n The optical fiber output module and the same two-dimensional polarization coherent beam combining module; 2 n The fiber optic output module outputs 2 n The sub-beams are coherently combined into the same laser beam by the two-dimensional polarization coherent beam combining module, and the m beams of laser light with different wavelengths output by the m two-dimensional polarization coherent beam combining modules are spectrally combined by the dispersion element to obtain a high-power laser.

2. The laser synthesis system combining polarization and spectrum according to claim 1, characterized in that: n is an integer greater than or equal to 2.

3. The laser synthesis system combining polarization and spectrum according to claim 2, characterized in that: The two-dimensional polarization coherent beam combining module consists of 2 n -1 beam combining assembly with polarization beam combining function is stacked in space; When n=2, the two-dimensional polarization coherent beam combining module includes three beam combining components, and the three beam combining components are stacked in an L shape; the sub-beams entering the two-dimensional polarization coherent beam combining module are arranged in a 2×2 structure, and the 2×2 sub-beams are incident in parallel on the same plane of the L shape; When n≥3, the structure of the two-dimensional polarization coherent beam combining module is flipped with the two-dimensional polarization coherent beam combining module corresponding to n-1 as a structural unit to obtain a mirror-symmetrical structure, and an additional beam combining component is added.

4. The polarization and spectrum combined laser synthesis system according to claim 3, characterized in that: The beam combining component is an integrated body formed by a half-wave plate, a polarization beam combining element and a reflector.

5. The polarization and spectrum combined laser synthesis system according to claim 4, characterized in that: When n=2, two of the three beam combining assemblies are stacked up and down, and the other one is placed vertically to form an L-shaped structure.

6. The polarization and spectrum combined laser synthesis system according to claim 5, characterized in that: The polarization beam combining element is a polarization beam combining prism or a birefringent crystal; the reflector is a 45° reflector; the rotation angle θ of the half-wave plate and the powers P1 and P2 of the two sub-beams incident on the corresponding beam combining component satisfy tanθ=P1 / P2.

7. The polarization and spectrum combined laser synthesis system according to claim 1, characterized in that: An optical fiber amplifier is provided between the phase control module and the optical fiber output module, m×2 n Each optical fiber amplifier is provided in the optical path of each light beam.

8. The polarization and spectrum combined laser synthesis system according to claim 1, characterized in that: The phase control module includes a phase controller and an FPGA phase control platform.

9. The laser synthesis system combining polarization and spectrum according to claim 1, characterized in that: The optical fiber output module is an output end cap.

10. A laser synthesis method combining polarization and spectrum, characterized in that: The laser synthesis system combining polarization and spectrum according to any one of claims 1 to 9 is adopted, wherein the lasers output by the m laser seed sources are respectively passed through the m optical fiber splitting modules, and each optical fiber splitting module splits the input laser into two n A sub-beam of the same wavelength, 2 n The sub-beams of the same wavelength are outputted through the corresponding phase control module and the optical fiber output module respectively, and are coherently combined into the same laser beam through the two-dimensional polarization coherent beam combining module. The m beams of laser beams with different wavelengths outputted by the m two-dimensional polarization coherent beam combining modules are spectrally combined by the dispersion element to obtain a high-power laser.

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