Stepless semiconductor laser device

Abstract

A stepless semiconductor laser device (10), comprising a chip base (11), a plurality of laser chips (119), a plurality of fast-axis collimating mirrors (12), a plurality of slow-axis collimating mirrors (13), a plurality of first reflecting mirrors (14) and a beam-combining assembly, wherein the plurality of laser chips (119) are arranged on a surface of one side of the chip base (11), and the plurality of laser chips (119) have the same height in a direction perpendicular to the surface of the chip base (11); the plurality of laser chips (119) are divided into two rows and respectively serve as a first light-emitting assembly (111) and a second light-emitting assembly (112), and the plurality of laser chips (119) in the first light-emitting assembly (111) and the plurality of laser chips (119) in the second light-emitting assembly (112) are arranged in a staggered manner; in the light emission direction of each laser chip (119), a fast-axis collimating mirror (12), a slow-axis collimating mirror (13) and a first reflecting mirror (14) are arranged in sequence; and the beam-combining assembly is located on light reflection paths of the first reflecting mirrors (14) and is configured to perform beam combination on laser light that passes through the first reflecting mirrors (14).

Description

step-free semiconductor lasers

[0001] This application claims priority to Chinese patent application No. 202410264054.2 filed on March 8, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present application relates to the field of laser technology, and in particular to a step-free semiconductor laser. Background Art

[0003] Semiconductor lasers have the advantages of small size, light weight, high electro-optical conversion efficiency, high reliability and long life. They have important applications in industrial processing, biomedicine and national defense. With the development of various industries, whether as a pump source or in direct application, further demands have been placed on semiconductor laser light sources. In the case of higher power requirements, in order to maintain high beam quality, laser beam combining must be performed. Laser beam combining is one of the effective technical approaches to achieve high-power, high-beam-quality semiconductor lasers. It combines multiple unit beams into a laser beam through geometric or physical optical means. Usually, the semiconductor laser structure arranges the laser chips in space in a step manner. To increase the power, the number of laser chips needs to be increased, which requires increasing the overall step height. As a result, the semiconductor laser cannot reduce the quality of the semiconductor laser while increasing the power.

[0004] That is, in the related art, the semiconductor laser cannot increase the power while reducing the quality of the semiconductor laser. Technical issues

[0005] The embodiments of the present application provide a step-free semiconductor laser, which can improve the power while reducing the quality of the semiconductor laser. Technical Solutions

[0006] In a first aspect, the step-less semiconductor laser provided by the present application includes a first main body plate, a second main body plate, and a connecting plate;

[0007] A step-less semiconductor laser, wherein the step-less semiconductor laser comprises a chip base, a plurality of laser chips, a plurality of fast-axis collimating mirrors, a plurality of slow-axis collimating mirrors, a plurality of first reflecting mirrors and a beam combining assembly;

[0008] Multiple laser chips are arranged on one side surface of the chip base, and the multiple laser chips have the same height in the direction perpendicular to the surface of the chip base; the multiple laser chips are divided into two rows and serve as the first light-emitting component and the second light-emitting component respectively, and the multiple laser chips in the first light-emitting component and the multiple laser chips in the second light-emitting component are staggered; the fast-axis collimator, the slow-axis collimator and the first reflector are sequentially arranged along the light emitting direction of each laser chip; the multiple first reflectors in the same row are staggered, and all of the first reflectors reflect the lasers emitted by the corresponding laser chips to the same direction; the beam combining component is located on the reflected light path of the first reflector, and is used to combine the lasers passing through the first reflector.

[0009] In one embodiment, the plurality of laser chips in the first light-emitting assembly are arranged at intervals along a first horizontal direction, and the first reflector reflects laser light emitted by the corresponding laser chip toward the first horizontal direction.

[0010] In one embodiment, the beam combining assembly includes a second reflector and a polarizer arranged in sequence along a second horizontal direction, and the multiple first reflectors on the optical path of the first light-emitting assembly reflect the lasers emitted by the multiple laser chips in the first light-emitting assembly along the first horizontal direction to the second reflectors, and the second reflectors reflect the lasers to the second horizontal direction, wherein the first horizontal direction and the second horizontal direction are different.

[0011] In one embodiment, the beam combining component includes a half-wave plate, and the multiple first reflectors on the optical path of the second light-emitting component reflect the lasers emitted by the multiple laser chips in the second light-emitting component along the first horizontal direction, and pass through the half-wave plate into the polarizer, and the polarizer polarizes the lasers to the second horizontal direction.

[0012] In one embodiment, the beam combining assembly includes a third reflector, and the second reflector, the polarizer, and the third reflector are arranged in sequence along the second horizontal direction. The polarizer couples the laser transmitted by the half-wave plate and the laser reflected by the second reflector, and allows the laser to enter the third reflector, and the third reflector reflects the laser in a direction opposite to the first horizontal direction.

[0013] In one embodiment, the beam combining assembly includes a focusing lens. The focusing lens and the third reflector are arranged in sequence in the first horizontal direction. The focusing lens is used to focus the laser reflected by the third reflector.

[0014] In one embodiment, a fiber optic mounting position is provided on the chip base, and the fiber optic mounting position, the focusing lens and the third reflector are arranged in sequence in the first horizontal direction. The fiber optic mounting position is used to install the optical fiber, and the focusing lens is used to focus the laser reflected by the third reflector onto the optical fiber of the fiber optic mounting position. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0016] FIG1 is a schematic diagram of the overall structure of an embodiment of a step-free semiconductor laser provided in an embodiment of the present application;

[0017] FIG2 is a schematic diagram of the propagation of an optical path at a top-down angle of the step-free semiconductor laser in one embodiment of the step-free semiconductor laser provided in an embodiment of the present application;

[0018] FIG3 is a schematic diagram of the optical path of a laser passing through a slow axis collimator, a first reflector, and a half-wave plate in sequence in an embodiment of a step-free semiconductor laser provided by an embodiment of the present application. Modes for Carrying Out the Invention

[0019] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0020] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0021] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0022] 1 to 3 , the step-free semiconductor laser 10 provided in the present application includes a chip base 11 , a plurality of laser chips 119 , a plurality of fast-axis collimating mirrors 12 , a plurality of slow-axis collimating mirrors 13 , a plurality of first reflecting mirrors 14 and a beam combining assembly.

[0023] The semiconductor laser pump source is one of the essential core components in solid-state lasers and fiber lasers. A high-power semiconductor laser pump source usually encapsulates multiple chips. The lasers emitted by these semiconductor chips are coupled into a multimode optical fiber after being collimated by an optical system. After being transmitted through the optical fiber, they are used to pump the solid gain medium or gain fiber. Due to the waveguide structure of the semiconductor laser, the laser emitted by the chip is usually elliptical. Its vertical divergence angle is relatively large, and the beam quality is good. It is called the "fast axis". The horizontal divergence angle is relatively small, and the beam quality is poor. It is called the "slow axis". In order to obtain a good coupling effect, the light beams in two directions need to be collimated separately. The corresponding components are called fast axis collimators 12 (Fast Axis Collimator, FAC) and slow axis collimators 13 (Slow Axis Collimator, SAC). The collimated chips are combined and then incident into the multimode optical fiber through a coupling mirror.

[0024] In the embodiment of the present application, multiple laser chips 119 are disposed on a side surface of the chip base 11, and the multiple laser chips 119 are at the same height in a direction perpendicular to the surface of the chip base 11. The multiple laser chips 119 are at the same height in a direction perpendicular to the surface of the chip base 11. Compared to traditional stepped semiconductor lasers, the stepless semiconductor laser 10 provided in the present application does not require an increase in step height and is lighter than ordinary semiconductor lasers. The distance from the laser chip 119 to the bottom of the chip base 11 is the same, and the heat dissipation effect of the chips is consistent and better than that of a stepped semiconductor laser.

[0025] In the embodiment of the present application, multiple laser chips 119 are arranged in two rows and serve as the first light-emitting assembly 111 and the second light-emitting assembly 112, respectively. The multiple laser chips 119 in the first light-emitting assembly 111 are staggered with the multiple laser chips 119 in the second light-emitting assembly 112. A fast-axis collimator 12, a slow-axis collimator 13, and a first reflector 14 are sequentially arranged along the light-emitting direction of each laser chip 119. Multiple first reflectors 14 in the same row are staggered, and all first reflectors 14 reflect the laser light emitted by the corresponding laser chip 119 in the same direction. A beam combining assembly is located on the reflected light path of the first reflector 14 and is used to combine the laser light passing through the first reflector 14. The laser light passes through the fast-axis collimator 12 and the slow-axis collimator 13 in sequence, achieving fast-axis superposition light and increasing the power of the step-free semiconductor laser 10.

[0026] In the embodiment of the present application, multiple laser chips 119 in the first light-emitting assembly 111 are arranged in a spaced-apart arrangement along the first horizontal direction F1. The first reflector 14 reflects the laser light emitted by the corresponding laser chip 119 in the first horizontal direction F1. The laser light emitted by the laser chip 119 sequentially passes through the fast-axis collimator 12 and the slow-axis collimator 13.

[0027] In this embodiment, the beam combining assembly includes a second reflector 15 and a polarizer 16 arranged sequentially along a second horizontal direction F2. Multiple first reflectors 14 on the optical path of the first light-emitting assembly 111 reflect laser light emitted by multiple laser chips 119 in the first light-emitting assembly 111 along the first horizontal direction F1 toward the second reflector 15. The second reflector 15 then reflects the laser light in the second horizontal direction F2. The first horizontal direction F1 and the second horizontal direction F2 are different. The multiple laser chips 119 emit beam-shaped laser light along the second horizontal direction F2.

[0028] Specifically, the mirror surface of the second reflector 15 is at a 45-degree angle to the first horizontal direction F1, and the second reflector 15 reflects the laser light in the first horizontal direction F1. Of course, in other embodiments, the mirror surface of the second reflector 15 can also be at other angles to the first horizontal direction F1, and this application does not limit this.

[0029] In the embodiment of the present application, the first horizontal direction F1 and the second horizontal direction F2 are perpendicular. Specifically, in Figure 2, the first horizontal direction F1 is rightward and the second horizontal direction F2 is downward. The first light-emitting assembly 111 and the second light-emitting assembly 112 are arranged sequentially along the second horizontal direction F2.

[0030] In the embodiment of the present application, the multiple first reflectors 14 on the optical path of the first light-emitting assembly 111 are arranged sequentially along the first horizontal direction F1, and the multiple first reflectors 14 on the optical path of the second light-emitting assembly 112 are arranged sequentially along the first horizontal direction F1. The multiple laser chips 119 in the first light-emitting assembly 111, the multiple laser chips 119 in the second light-emitting assembly 112, the multiple first reflectors 14 on the optical path of the first light-emitting assembly 111, and the multiple first reflectors 14 on the optical path of the second light-emitting assembly 112 are arranged in four rows.

[0031] Specifically, the multiple first reflectors 14 on the optical path of the first light-emitting assembly 111 serve as the first reflective light assembly, and the multiple first reflectors 14 on the optical path of the second light-emitting assembly 112 serve as the second reflective light assembly. The multiple first reflectors 14 in the first reflective light assembly and the multiple first reflectors 14 in the second reflective light assembly are arranged alternately. The first light-emitting assembly 111, the second light-emitting assembly 112, the first reflective light assembly, and the second reflective light assembly are arranged sequentially in the second horizontal direction F2.

[0032] In an embodiment of the present application, the beam combining component includes a half-wave plate 17, and multiple first reflectors 14 on the optical path of the second light-emitting component 112 reflect the lasers emitted by the multiple laser chips 119 in the second light-emitting component 112 along the first horizontal direction F1, and pass through the half-wave plate 17 into the polarizer 16. The polarizer 16 polarizes the laser to the second horizontal direction F2 and enters the third reflector 18.

[0033] A birefringent crystal of a certain thickness, when normally incident light passes through it, has a phase difference between the ordinary light (o light) and the extraordinary light (e light) equal to π or an odd multiple thereof. Such a crystal is called a half-wave plate, or simply a half-wave plate 17. A half-wave plate 17 can rotate polarized light. Because linearly polarized light is perpendicular to the half-wave plate 17, the transmitted light remains linearly polarized.

[0034] As shown in FIG3 , the polarization angle of the laser reflected by the first reflector 14 is α. The first reflector 14 reflects the laser emitted by the corresponding laser chip 119 to the second horizontal direction F2 and reaches the half-wave plate 17. The half-wave plate 17 adjusts the polarization angle of the laser to θ.

[0035] In an embodiment of the present application, the beam combining assembly includes a third reflector 18, and the second reflector 15, the polarizer 16 and the third reflector 18 are arranged in sequence along the second horizontal direction F2. The polarizer 16 couples the laser transmitted by the half-wave plate 17 and the laser reflected by the second reflector 15, and allows the laser to enter the third reflector 18. The third reflector 18 reflects the laser in a direction opposite to the first horizontal direction F1.

[0036] A polarizer is an optical element that converts natural light into polarized light. It has the function of both blocking and transmitting incident light. It comes in two types: black and white, and color. Based on its application, it can be further categorized as transmission, transflection, and transflection. There are many types of artificial polarizers. One method uses a polyvinyl alcohol film, a polymer compound with a network structure, as a substrate. It is then impregnated with iodine, which has a strong dichroic property. After stabilization with boric acid solution, the film is then uniaxially stretched 4-5 times. After stretching, the iodine molecules are neatly adsorbed and arranged on the film, providing polarization or analysis properties.

[0037] In the embodiment of the present application, the beam combining assembly includes a focusing lens 191. The focusing lens 191 and the third reflector 18 are arranged in sequence in the first horizontal direction F1. The focusing lens 191 is used to focus the laser light reflected by the third reflector 18. Specifically, the first light-emitting assembly 111, the second light-emitting assembly 112, the first reflective light assembly, the second reflective light assembly, and the focusing lens 191 are arranged in sequence in the second horizontal direction F2. This layout can improve the compactness of the device layout of the step-free semiconductor laser 10 and further reduce the volume of the step-free semiconductor laser 10.

[0038] In an embodiment of the present application, a fiber optic mounting position 192 is provided on the chip base 11. The fiber optic mounting position 192, the focusing lens 191 and the third reflector 18 are arranged in sequence in the first horizontal direction F1. The fiber optic mounting position 192 is used to install the optical fiber, and the focusing lens 191 is used to focus the laser reflected by the third reflector 18 onto the optical fiber of the fiber optic mounting position 192.

[0039] In the embodiment of the present application, the surface of the half-wave plate 17 is perpendicular to the first horizontal direction F1.

[0040] In the embodiment of the present application, the surface of the polarizer 16 is inclined with respect to the first horizontal direction F1. Specifically, the surface of the polarizer 16 forms an angle of 45 degrees with respect to the first horizontal direction F1.

[0041] In the embodiment of the present application, the chip base 11 is made of aluminum diamond. Aluminum diamond is a composite material composed of an aluminum alloy matrix and diamond particles as reinforcement. It has very similar properties to aluminum silicon carbide, but has significant advantages in thermal conductivity, thermal expansion, and other properties.

[0042] As shown in FIG3 , the optical path of the step-free semiconductor laser 10 in the embodiment of the present application is as follows:

[0043] The lasers emitted by the multiple laser chips 119 on the optical path of the first light-emitting component 111 pass through the fast-axis collimator 12 and the slow-axis collimator 13 in sequence and enter the first reflector 14 on the optical path of the first light-emitting component 111. The first reflector 14 on the optical path of the first light-emitting component 111 reflects the lasers emitted by the corresponding laser chips 119 to the first horizontal direction F1 and enters the second reflector 15. The second reflector 15 reflects the lasers to the second horizontal direction F2 and passes through to enter the polarizer 16.

[0044] The lasers emitted by the multiple laser chips 119 on the optical path of the second light-emitting component 112 pass through the fast-axis collimator 12 and the slow-axis collimator 13 in sequence and enter the first reflector 14 on the optical path of the second light-emitting component 112. The multiple first reflectors 14 on the optical path of the second light-emitting component 112 reflect the lasers emitted by the multiple laser chips 119 in the second light-emitting component 112 along the first horizontal direction F1, and pass through the half-wave plate 17 to enter the polarizer 16.

[0045] The light path of the first light-emitting component 111 and the light path of the second light-emitting component 112 enter the polarizer 16 along the second horizontal direction F2 and the first horizontal direction F1 respectively. The polarizer 16 polarizes the laser light reflected in the first horizontal direction F1 by the multiple first reflectors 14 on the light path of the second light-emitting component 112 to the second horizontal direction F2. The polarizer 16 polarizes the laser light reflected in the second horizontal direction F2 by the second reflector 15 to the second horizontal direction F2. The polarizer 16 couples the laser light in two directions and emits it toward the third reflector 18 along the second horizontal direction F2.

[0046] Compared with the related art, the step-free semiconductor laser of the present application includes a chip base, multiple laser chips, multiple fast-axis collimators, multiple slow-axis collimators, multiple first reflectors and a beam combining component; multiple laser chips are arranged on one side surface of the chip base, and the multiple laser chips have the same height in the direction perpendicular to the surface of the chip base; multiple laser chips are divided into two rows and serve as the first light-emitting component and the second light-emitting component respectively, and the multiple laser chips in the first light-emitting component and the multiple laser chips in the second light-emitting component are staggered; fast-axis collimators, slow-axis collimators and first reflectors are arranged in sequence along the light-emitting direction of each laser chip; multiple first reflectors in the same row are staggered, and all first reflectors reflect the laser emitted by the corresponding laser chip to the same direction; the beam combining component is located on the reflected light path of the first reflector, and is used to combine the laser passing through the first reflector. The present application arranges multiple laser chips at the same height on the chip base. The multiple laser chips are at the same height from the bottom of the chip base. Compared with the traditional stepped semiconductor laser, there is no need to increase the step height and the volume is smaller. At the same time, the light output direction of each laser chip is sequentially provided with a fast-axis collimator, a slow-axis collimator and a first reflector, which can realize laser beam combining in the fast axis and increase the power, thereby reducing the quality of the semiconductor laser while increasing the power.

[0047] The stepless semiconductor laser of this application does not require designing the step height. It uses highly efficient thermally conductive materials such as aluminum diamond, is easy to process and shape, and has the advantages of small size, light weight, and good heat dissipation. The stepless semiconductor laser of this application focuses light along the fast axis and the slow axis, and then uses a first reflector to direct the light obliquely upward. After passing through a half-wave plate, the light is then coupled into a focusing lens by adjusting the angle of the polarizer and then into the optical fiber.

[0048] The stepless semiconductor laser in this application does not require additional steps and is lighter than conventional semiconductor lasers. The distance between the laser chip and the bottom of the base remains constant, resulting in consistent heat dissipation from the laser chip and better heat dissipation than conventional semiconductor lasers with steps. The stepless semiconductor laser also boasts higher coupling efficiency than conventional semiconductor lasers with steps.

[0049] The above is a detailed introduction to a stepless semiconductor laser provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, based on the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

[0050] It should be noted that when the above embodiments of this application are applied to specific products or technologies, the relevant data of the user is involved, and the user's permission or consent must be obtained, and the collection, use and processing of the relevant data must comply with relevant laws, regulations and standards.

Claims

1. A step-free semiconductor laser, wherein: The step-free semiconductor laser comprises a chip base, a plurality of laser chips, a plurality of fast-axis collimating mirrors, a plurality of slow-axis collimating mirrors, a plurality of first reflecting mirrors and a beam combining assembly; Multiple laser chips are arranged on one side surface of the chip base, and the multiple laser chips have the same height in the direction perpendicular to the surface of the chip base; the multiple laser chips are divided into two rows and serve as the first light-emitting component and the second light-emitting component respectively, and the multiple laser chips in the first light-emitting component and the multiple laser chips in the second light-emitting component are staggered; the fast-axis collimator, the slow-axis collimator and the first reflector are sequentially arranged along the light emitting direction of each laser chip; the multiple first reflectors in the same row are staggered, and all of the first reflectors reflect the lasers emitted by the corresponding laser chips to the same direction; the beam combining component is located on the reflected light path of the first reflector, and is used to combine the lasers passing through the first reflector.

2. The stepless semiconductor laser according to claim 1, wherein The plurality of laser chips in the first light-emitting assembly are arranged at intervals along a first horizontal direction, and the first reflector reflects laser light emitted by the corresponding laser chip toward the first horizontal direction.

3. The stepless semiconductor laser according to claim 2, wherein: The beam combining assembly includes a second reflector and a polarizer arranged in sequence along a second horizontal direction. The multiple first reflectors on the optical path of the first light-emitting assembly reflect the lasers emitted by the multiple laser chips in the first light-emitting assembly along the first horizontal direction to the second reflectors, and the second reflectors reflect the lasers to the second horizontal direction, wherein the first horizontal direction and the second horizontal direction are different.

4. The stepless semiconductor laser according to claim 3, wherein The beam combining component includes a half-wave plate, and the multiple first reflectors on the optical path of the second light-emitting component reflect the lasers emitted by the multiple laser chips in the second light-emitting component along the first horizontal direction, and pass through the half-wave plate into the polarizer, and the polarizer polarizes the lasers to the second horizontal direction.

5. The stepless semiconductor laser according to claim 4, wherein The beam combining assembly includes a third reflector, and the second reflector, the polarizer, and the third reflector are sequentially arranged along the second horizontal direction. The polarizer couples the laser light transmitted by the half-wave plate and the laser light reflected by the second reflector, and allows the laser light to enter the third reflector. The third reflector reflects the laser light in a direction opposite to the first horizontal direction.

6. The stepless semiconductor laser according to claim 5, wherein The beam combining assembly includes a focusing lens. The focusing lens and the third reflector are arranged in sequence in the first horizontal direction. The focusing lens is used to focus the laser reflected by the third reflector.

7. The stepless semiconductor laser according to claim 6, wherein: A fiber optic mounting position is provided on the chip base. The fiber optic mounting position, the focusing lens and the third reflector are arranged in sequence in the first horizontal direction. The fiber optic mounting position is used to install the optical fiber, and the focusing lens is used to focus the laser reflected by the third reflector onto the optical fiber of the fiber optic mounting position.

8. The stepless semiconductor laser according to claim 4, wherein A surface of the half-wave plate is perpendicular to the first horizontal direction.

9. The stepless semiconductor laser according to claim 4, wherein: A surface of the polarizer is inclined with respect to the first horizontal direction.

10. The stepless semiconductor laser according to claim 1, wherein The chip base is made of aluminum diamond.

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