Semiconductor laser coupling system

Abstract

The application relates to the technical field of semiconductor lasers, and discloses a semiconductor laser coupling system which comprises a first laser chip, a second laser chip, a collimating optical assembly and a beam combining assembly. The beam combining assembly comprises at least one multi-angle prism which is provided with a through hole penetrating along an optical axis and a plurality of reflecting surfaces arranged around the through hole. The first laser chip is arranged on the outer circumferential side of the multi-angle prism; the second laser chip is arranged on the side of the beam combining assembly away from the focusing lens group along the optical axis, and the collimated laser directly passes through the through hole. The focusing lens group focuses and couples the laser passing through the through hole to an output optical fiber. The multi-layer multi-angle prisms are coaxially stacked and have different side numbers, and the reflecting surfaces are distributed along different azimuth angles in a plane perpendicular to the optical axis, so that the combined light spot profile formed by all the lasers on the incident surface of the focusing lens group matches a circular receiving area defined by the numerical aperture of the output optical fiber. The application improves the utilization rate of the numerical aperture of the optical fiber, improves the uniformity of the light spot energy, and realizes efficient coupling of multiple lasers.

Description

Technical Field

[0001] This application relates to the field of semiconductor laser technology, and more particularly to a semiconductor laser coupling system. Background Technology

[0002] Semiconductor lasers possess advantages such as high electro-optical efficiency, small size, and wide wavelength coverage, leading to their widespread application in industrial processing, laser lighting, fiber optic communication, and solid-state laser pumping. However, the output power of a single semiconductor laser chip is limited, and its brightness and beam quality often fail to simultaneously meet the demands of high-power applications. Therefore, multiple semiconductor laser chips are typically used for beam combining and coupling, converging multiple laser beams and coupling them into the same output fiber to enhance both output power and brightness.

[0003] In an architecture where multiple laser chips are combined and coupled into an optical fiber, the beams output from each chip are collimated, combined, and focused to form a combined spot on the incident surface of the focusing lens and the end face of the fiber core. Since the receiving capability of an optical fiber is determined by its numerical aperture (NA), theoretically only light falling within the circular region on the focusing surface that satisfies the fiber's NA can be effectively coupled into the fiber. However, in existing multi-chip coupling systems, the distribution of the combined spot on the focusing surface after multiple laser beams are combined often does not match the circular receiving area defined by the fiber's NA. For example... Figure 1 As shown, when multiple laser chips are arranged in a linear array, the combined beam expands in the slow axis direction and compresses in the fast axis direction, resulting in a rectangular or near-rectangular distribution. This causes the corners of the circular NA region on the focusing surface (especially the large NA region) to be left uncovered by the beam, resulting in a waste of the fiber numerical aperture. Even if multiple beams are combined by means of beam turning, folding, etc., the beams often occupy the same space on the focusing surface in a single way, resulting in uneven beam energy distribution and limited coupling efficiency. Summary of the Invention

[0004] In view of this, this application proposes a semiconductor laser coupling system to solve the technical problems in the prior art where the combined spot after multiple laser beams are combined does not match the receiving area of ​​the fiber numerical aperture, resulting in low utilization of the fiber numerical aperture and uneven energy distribution of the spot.

[0005] The technical solution of this application is implemented as follows: This application provides a semiconductor laser coupling system, including: Multiple first laser chips and at least one second laser chip are used to output laser light; Multiple collimating optical components are provided, each of which is disposed in the output optical path of a first laser chip or a second laser chip, for collimating the laser output from the laser chip. A beam combining assembly includes at least one polygonal prism, wherein the central region of the polygonal prism has a through hole extending along the optical axis, and the periphery of the through hole has multiple reflective surfaces; the first laser chip is disposed on the outer periphery of the polygonal prism, and each of the reflective surfaces corresponds to one first laser chip, for refracting the collimated laser output from the first laser chip and passing it through the through hole; A focusing lens group is disposed in the output optical path of the beam combining assembly to focus the laser light passing through the through hole and couple it to the output optical fiber; The second laser chip is disposed on the optical axis of the beam combining assembly and located on the side away from the focusing lens group, and the collimated laser output from it passes directly through the through hole; When the beam combining assembly includes at least two layers of polygonal prisms, the polygonal prisms are coaxially stacked and have different numbers of sides, and the reflecting surfaces of each polygonal prism are distributed along different azimuth angles in a plane perpendicular to the optical axis, so that the outline of the combined light spot formed by all the lasers passing through the through hole on the incident surface of the focusing lens group matches the circular receiving area defined by the numerical aperture of the output optical fiber.

[0006] Based on the above technical solution, preferably, the polygonal prism has 2n sides, where n is an integer greater than or equal to 2.

[0007] Based on the above technical solution, preferably, a plurality of the first laser chips are evenly distributed around the outer periphery of the polygonal prism, and the light emission direction of each first laser chip is perpendicular to the side of the corresponding polygonal prism.

[0008] Based on the above technical solution, preferably, the reflecting surface of each polygonal prism is a plane at a 45° angle to the optical axis, used to refract the incident laser by 90°.

[0009] Based on the above technical solution, preferably, the aperture of the through hole is greater than or equal to the outer diameter of the combined spot of the collimated laser output from the second laser chip at the through hole.

[0010] Based on the above technical solution, preferably, when the beam combining assembly includes multiple polygonal prisms, the number of sides of each polygonal prism decreases sequentially from the side closest to the focusing lens group to the side furthest from the focusing lens group along the optical axis.

[0011] Based on the above technical solution, preferably, when the beam combining assembly includes multiple polygonal prisms, the reflecting surfaces on adjacent polygonal prisms are staggered in the radial direction.

[0012] Based on the above technical solution, preferably, the reflective surface of the polygonal prism is provided with a high-reflectivity film.

[0013] Based on the above technical solution, preferably, the collimating optical component includes a fast-axis collimating lens and a slow-axis collimating lens, the fast-axis collimating lens is attached to the light-emitting end face of the corresponding laser chip, and the slow-axis collimating lens is arranged in the light-emitting direction of the fast-axis collimating lens.

[0014] Based on the above technical solution, preferably, a substrate is fixedly disposed on the outer periphery of the polygonal prism, the first laser chip and the corresponding collimating optical component are fixedly disposed on the surface of the substrate, and a cooling channel is formed in the substrate.

[0015] This application has the following advantages over the prior art: 1) The semiconductor laser coupling system proposed in this application uses a polygonal prism with a central through-hole and a reflective surface to reflect and refract the beam of the first laser chip through the through-hole, while simultaneously allowing the beam of the second laser chip to pass directly through the through-hole along the optical axis. With multiple polygonal prisms, coaxial stacking and azimuth-differentiated distribution are achieved, so that the outline of the combined spot formed by all lasers on the incident surface of the focusing lens group matches the circular receiving area defined by the numerical aperture of the output fiber. This improves the utilization rate of the fiber's numerical aperture, enhances the uniformity of the spot energy distribution, and achieves efficient coupling of multiple lasers.

[0016] 2) By setting the polygonal prism to have an even number of sides, the polygonal prism has a symmetrical geometric structure, which allows each reflecting surface to be evenly distributed along the circumference in a plane perpendicular to the optical axis. This is beneficial for the beams of each first laser chip to form symmetrical annular spots after reflection.

[0017] 3) Multi-layer polygonal prisms are coaxially stacked, with the number of sides of each prism decreasing sequentially from the outside to the inside. The outer prism's reflecting surface forms a larger diameter annular spot, while the inner prism's reflecting surface forms a smaller diameter annular spot. The annular spots are nested sequentially from the outside to the inside. Through the coordinated action of this multi-layered nested annular spot and the central spot, all laser beams together form an approximately solid circular combined spot on the incident surface of the focusing lens group. The outline of this combined spot matches the circular receiving area defined by the numerical aperture of the output fiber, fully filling the circular receiving area. This significantly improves the utilization rate of the fiber's numerical aperture, enhances the uniformity of the spot energy distribution, and achieves efficient coupling of multiple laser beams and maximizes the output power.

[0018] 4) By fixing a substrate to the outer periphery of the polygonal prism, the first laser chip and the corresponding collimating optical components are integrated and mounted on the substrate surface, ensuring the positioning accuracy and assembly consistency of each component and simplifying the assembly process; the cooling channels opened in the substrate can be circulated with cooling medium to effectively remove the heat generated by the first laser chip during operation, ensuring the thermal stability and long-term reliability of the system under high power conditions. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the laser beams output from multiple laser chips in a conventional laser on the output optical fiber. Figure 2 This is a schematic diagram of the semiconductor laser coupling system disclosed in the embodiments of this application; Figure 3 This is a three-dimensional structural schematic diagram of the bundle combining component disclosed in the embodiments of this application; Figure 4 This is an exploded view of the bundle-combining component disclosed in an embodiment of this application; Figure 5 This is a schematic diagram of the planar structure of the semiconductor laser coupling system disclosed in the embodiments of this application; Figure 6 for Figure 5 Planar sectional view at point AA; Figure 7 This is a schematic diagram of a laser spot on an output optical fiber generated by multiple laser chips disclosed in an embodiment of this application. Figure 8 This is a schematic diagram of another type of laser spot on the output optical fiber of the laser output from the multiple laser chips disclosed in the embodiments of this application; Figure label: 1. First laser chip; 2. Second laser chip; 3. Collimating optical assembly; 4. Beam combiner assembly; 41. Polygonal prism; 411. Through hole; 412. Reflecting surface; 5. Focusing lens group; M. High reflectivity film; 31. Fast axis collimating lens; 32. Slow axis collimating lens; 6. Substrate; S. Output optical fiber; G. Optical axis. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0023] In the description of the embodiments of this application, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0025] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0026] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application; however, those skilled in the art will recognize the applicability of other processes and / or the use of other materials.

[0027] like Figure 2 As shown, combined with Figure 3-8 This application discloses a semiconductor laser coupling system, including a first laser chip 1, a second laser chip 2, a collimating optical component 3, a beam combining component 4, and a focusing lens group 5.

[0028] The system comprises two laser chips: a first laser chip 1 and a second laser chip 2, each responsible for outputting laser light. Multiple first laser chips 1 are configured, and their output laser light is refracted by a beam combiner 4 to form an outer ring-shaped spot, covering the outer portion of the circular receiving area defined by the fiber optic numerical aperture. The second laser chip 2 supplements the laser energy in the central region; its output laser light passes directly through the through-hole 411 to form a central spot. Together, they constitute the light source of the system, enabling the combined spot to completely cover the circular receiving area defined by the fiber optic numerical aperture.

[0029] Each laser chip 1 or laser chip 2 has a corresponding collimating optical component 3 installed in its output optical path. The collimating optical component 3 is used to collimate the diverging laser output from the laser chip, making it an approximately parallel beam for subsequent beam combining and focusing operations. Through collimation, the divergence angle of the beam can be effectively controlled, improving coupling efficiency.

[0030] The beam combining assembly 4 includes at least one polygonal prism 41. A through-hole 411 extending along the optical axis G is formed in the central region of the polygonal prism 41, and multiple reflecting surfaces 412 are arranged around the periphery of the through-hole 411. A first laser chip 1 is disposed on the outer periphery of the polygonal prism 41, with each reflecting surface 412 corresponding to one first laser chip 1. The collimated laser beam output from the first laser chip 1 is incident on the corresponding reflecting surface 412, deflected by the reflecting surface 412, changes its propagation direction, and propagates through the through-hole 411 towards the focusing lens group 5. This structure allows the beams from multiple first laser chips 1 to be spatially distributed along different azimuth angles, which is beneficial for forming a uniformly distributed combined beam spot on the focusing surface.

[0031] The focusing lens group 5 is positioned in the output optical path of the beam combiner 4 to focus all the laser light passing through the through-hole 411 and couple the focused laser light to the output fiber S. The focusing lens group 5 serves to converge the beam and match the numerical aperture of the fiber, and is a key component for achieving efficient coupling.

[0032] The second laser chip 2 is disposed on the optical axis G of the beam combiner assembly 4, and is located on the side away from the focusing lens group 5. The collimated laser output from the second laser chip 2 passes directly through the through-hole 411 along the optical axis G without passing through any reflecting surface 412, and is incident on the focusing lens group 5. This design allows the beam from the second laser chip 2 to fill the central region of the combined beam spot, forming a complete combined beam spot together with the annular distributed beam from the first laser chip 1, further improving the utilization rate of the fiber numerical aperture.

[0033] It should be noted that in this embodiment, the optical axis G refers to the optical axis G of the focusing lens group 5, and is also the common optical axis G of the beam combining assembly 4 and the output optical fiber S. Furthermore, the optical axis G and the central axis of the through-hole 411 are coaxial, and the centers of all optical elements are located on this optical axis G to ensure the coaxiality of the system and the symmetry of beam transmission.

[0034] When the beam combining assembly 4 includes at least two layers of polygonal prisms 41, the polygonal prisms 41 are coaxially stacked and have different numbers of sides. In a plane perpendicular to the optical axis G, the polygonal prism 41 with more sides is located in the outer layer, and the polygonal prism 41 with fewer sides is located in the inner layer. The reflecting surfaces 412 of the outer polygonal prism 41 refract the beam corresponding to the first laser chip 1 to form a larger diameter annular spot on the incident surface of the focusing lens group 5; the reflecting surfaces 412 of the inner polygonal prism 41 refract the beam corresponding to the first laser chip 1 to form a smaller diameter annular spot on the incident surface, and the smaller annular spot is located inside the larger annular spot. At the same time, the laser output from the second laser chip 2 passes directly through the through-hole 411 and forms a central spot in the central region of the incident surface. Thus, the combined light spot formed by all the laser beams on the incident surface of the focusing lens group 5 consists of a large-diameter annular spot, a small-diameter annular spot, and a central spot, arranged sequentially from the outside in, together forming an approximately solid circular spot. The outline of this circular spot matches the circular receiving area defined by the numerical aperture of the output fiber S, fully filling the circular receiving area and coupling as much laser energy as possible into the output fiber S, thereby maximizing the output power. This multi-layered nested annular spot filling method overcomes the shortcomings of traditional linear array arrangements where the combined light spot is rectangular and can only cover the middle part of the circular receiving area, significantly improving the utilization rate of the fiber's numerical aperture and the uniformity of the light spot energy distribution.

[0035] The semiconductor laser coupling system proposed in this application uses a polygonal prism 41 with a central through-hole 411 and a reflecting surface 412 to reflect and refract the beam of the first laser chip 1 through the through-hole 411, while simultaneously allowing the beam of the second laser chip 2 to pass directly through the through-hole 411 along the optical axis G. With multiple polygonal prisms 41, coaxial stacking and azimuth-differentiated distribution are achieved, ensuring that the contour of the combined beam formed on the incident surface of the focusing lens group 5 matches the circular receiving area defined by the numerical aperture of the output fiber S. This improves the utilization rate of the fiber's numerical aperture, enhances the uniformity of the beam energy distribution, and achieves efficient coupling of multiple laser beams.

[0036] In some embodiments, a plurality of first laser chips 1 are uniformly distributed around the outer periphery of the polygonal prism 41, and the light emission direction of each first laser chip 1 is perpendicular to the side surface of the corresponding polygonal prism 41. The uniform distribution ensures that the first laser chips 1 are arranged at equal intervals in the azimuth angle, ensuring that after each beam is refracted by the reflecting surface 412, the spacing between the beams in the annular light spot formed on the incident surface of the focusing lens group 5 is uniform, which is beneficial to the symmetry and uniformity of the combined light spot.

[0037] The light output direction of each first laser chip 1 is perpendicular to the side of the corresponding polygonal prism 41, ensuring that the incident light enters the prism at a zero-degree incident angle. After being refracted by the reflecting surface 412, the outgoing light can propagate strictly along the optical axis G, avoiding beam deflection or spot distortion caused by incident angle deviation. This ensures that the refraction angle of each beam is consistent, which is beneficial for the subsequent focusing lens group 5 to focus and efficiently couple each beam.

[0038] Each polygonal prism 41 has a reflecting surface 412 that forms a 45° angle with the optical axis G, used to deflect the incident laser beam by 90°. The 45° angle between the reflecting surface 412 and the optical axis G ensures that the laser beam incident horizontally from the first laser chip 1 is reflected and propagates along the optical axis G, achieving a 90° deflection. This fixed deflection angle ensures that all beams processed by the reflecting surface 412 have the same propagation direction, facilitating unified focusing of multiple laser beams by the focusing lens group 5. The 45° reflecting surface 412 has a simple structure, is easy to manufacture and assemble, and has high deflection efficiency, effectively reducing light energy loss and improving the overall optical efficiency of the system.

[0039] In some embodiments, the reflective surface 412 of the polygonal prism 41 is provided with a high-reflectivity film M. Specifically, the high-reflectivity film M can be fixed to the reflective surface 412 by adhesive bonding or coating. The high-reflectivity film M can significantly improve the reflectivity of the reflective surface 412 to incident laser light and reduce light energy loss during reflection. The high-reflectivity film M can be composed of multiple dielectric films or metal films, and has extremely high reflectivity for a specific laser wavelength, reaching over 99%. By setting the high-reflectivity film M, laser energy can be retained to the maximum extent, improving the overall optical efficiency of the system, while reducing the temperature rise of the reflective surface 412 due to laser energy absorption, thus enhancing the thermal stability and long-term reliability of the system.

[0040] In some embodiments, the polygonal prism 41 has 2n sides, where n is an integer greater than or equal to 2. This means that the polygonal prism 41 can be a quadrilateral, hexagon, octagon, decagon, or other polygons with an even number of sides. The design of an even number of sides ensures that the polygonal prism 41 has a symmetrical geometric structure, so that each reflecting surface 412 can be uniformly distributed along the circumference in a plane perpendicular to the optical axis G, which is beneficial for the beams of each first laser chip 1 to form symmetrical annular light spots after reflection.

[0041] When the beam combiner 4 contains only one layer of polygonal prism 41, the number of sides of this polygonal prism 41 can be quadrilateral, hexagonal, or octagonal, etc. Taking a regular quadrilateral as an example, the prism has four reflecting surfaces 412, which can be correspondingly set with four first laser chips 1. The four first laser chips 1 are evenly distributed around the outer periphery of the prism. After each beam is refracted by the reflecting surfaces 412, it forms an annular spot composed of four light spots, which is suitable for applications with small fiber numerical aperture or low power requirements. As the number of sides of the prism increases, the number of first laser chips 1 that can be accommodated increases accordingly, and the filling density of the annular spot also increases.

[0042] When the beam combining assembly 4 includes two layers of polygonal prisms 41, the two prisms are coaxially stacked and have different numbers of sides. For example, the outer layer can be an octagonal prism, and the inner layer can be a hexagonal prism. The eight reflecting surfaces 412 of the outer octagonal prism correspond to the eight first laser chips 1, forming a large-diameter annular spot on the incident surface of the focusing lens group 5; the six reflecting surfaces 412 of the inner hexagonal prism correspond to the six first laser chips 1, forming a smaller-diameter annular spot on the incident surface, and the smaller annular spot is located inside the larger annular spot. The reflecting surfaces 412 of the two prisms are distributed at different azimuth angles in a plane perpendicular to the optical axis G, so that the positions of the annular spots of the inner and outer layers are staggered, avoiding overlap, thereby achieving a higher filling density in the annular region.

[0043] For example, the outer layer can use a hexagonal prism, and the inner layer can use a quadrilateral prism. The six reflecting surfaces 412 of the outer hexagonal prism correspond to the six first laser chips 1, forming a larger annular spot; the four reflecting surfaces 412 of the inner quadrilateral prism correspond to the four first laser chips 1, forming a smaller annular spot, located inside the larger annular spot. Both configurations can achieve a nested distribution of the inner and outer annular spots, effectively filling the circular receiving area defined by the numerical aperture of the optical fiber.

[0044] When the beam combining assembly 4 includes three layers of polygonal prisms 41, the three layers of prisms are coaxially stacked and have different numbers of sides. Along the optical axis G, from the side closer to the focusing lens group 5 to the side farther away from the focusing lens group 5, the number of sides of each layer of polygonal prisms 41 decreases sequentially.

[0045] As an example, the outer layer can be an octagonal prism, the middle layer a hexagonal prism, and the inner layer a quadrilateral prism. The eight reflecting surfaces 412 of the outer octagonal prism correspond to the eight first laser chips 1, forming the largest diameter annular spot on the incident surface of the focusing lens group 5. The six reflecting surfaces 412 of the middle hexagonal prism correspond to the six first laser chips 1, forming a centrally located annular spot on the incident surface, inside the outermost annular spot. The four reflecting surfaces 412 of the inner quadrilateral prism correspond to the four first laser chips 1, forming the smallest diameter annular spot on the incident surface, inside the centrally located annular spot. The reflecting surfaces 412 of the three prisms are distributed at different azimuth angles in a plane perpendicular to the optical axis G, causing the positions of the annular spots in each layer to intersect, avoiding overlap and thus achieving a higher filling density within the annular region.

[0046] As another example, the outer layer can use a decagonal prism, the middle layer can use an octagonal prism, and the inner layer can use a hexagonal prism. The ten reflecting surfaces 412 of the outer decagonal prism correspond to the ten first laser chips 1, forming the largest diameter annular spot; the eight reflecting surfaces 412 of the middle octagonal prism correspond to the eight first laser chips 1, forming a medium-diameter annular spot; and the six reflecting surfaces 412 of the inner hexagonal prism correspond to the six first laser chips 1, forming the smallest diameter annular spot. These three layers of annular spots are nested sequentially from the outside in, with the positions of each layer interleaved, together forming a high-density annular filling region.

[0047] For configurations with four or more polygonal prisms 41, the design principle is consistent with the three-layer configuration. Specifically, along the optical axis G, from the side closest to the focusing lens group 5 to the side furthest from it, the number of sides of each polygonal prism 41 decreases sequentially. Furthermore, the reflecting surfaces 412 of each prism are distributed at different azimuth angles in a plane perpendicular to the optical axis G, causing the positions of the annular light spots in each layer to intersect. In practical design, the number of layers depends on the diameter of the circular receiving area defined by the numerical aperture of the output fiber S. When the fiber numerical aperture and the diameter of the circular receiving area are large, more layers of prisms can be used to arrange more first laser chips 1 within the annular area, further improving the fill density and output power.

[0048] For example, a four-layer configuration can use dodecagonal, decagonal, octagonal, and hexagonal prisms sequentially from the outside in, or vice versa. A five-layer configuration can use fourteen-sided, dodecagonal, decagonal, octagonal, and hexagonal prisms sequentially from the outside in. In short, the more layers there are, the more first laser chips can be accommodated, and the higher the filling density of the annular spot. However, this also places higher demands on the processing and assembly precision of the prisms. Therefore, the selection of the number of layers needs to strike a balance between the fiber numerical aperture, output power requirements, and manufacturing costs.

[0049] In some embodiments, the aperture of the through-hole 411 is greater than or equal to the outer diameter of the combined spot of the collimated laser output from the second laser chip 2 at the through-hole 411. The second laser chip 2 is disposed on the optical axis G of the beam combining assembly 4, and the collimated laser output from it passes directly through the through-hole 411 along the optical axis G and is incident on the focusing lens group 5. When there is only one second laser chip 2, the collimated laser output from it forms a spot at the through-hole 411, and the outer diameter of this spot is the diameter of the single spot.

[0050] When there are multiple second laser chips 2, the collimated laser beams output from these chips form a group of light spots at the through-hole 411. These spots are arranged side-by-side, and the diameter formed by their outermost contours is the outer diameter of the combined light spot. The aperture of the through-hole 411 is greater than or equal to the outer diameter of the combined light spot, ensuring that all laser beams output from the second laser chips 2 can pass through the through-hole 411 without obstruction. This prevents the edges of the through-hole 411 from truncating or blocking the beams from the second laser chips 2, thus ensuring that the laser energy in the central region is transmitted to the focusing lens group 5 intact and without loss. If the aperture of the through-hole 411 is smaller than the outer diameter of the combined light spot of the second laser chips 2, some of the beams from the second laser chips 2 will be blocked or truncated by the edges of the through-hole 411, resulting in light energy loss. At the same time, the truncated beams may also produce diffraction or scattering, affecting the quality and coupling efficiency of the combined light spot. Therefore, setting the aperture of the through hole 411 to be no less than the outer diameter of the combined beam of the second laser chip 2 is a necessary condition to ensure the complete transmission of the beam of the second laser chip 2, which helps to achieve efficient coupling of multiple lasers and maximize output power.

[0051] In this embodiment, the number of second laser chips 2 is related to the number of sides of the innermost polygonal prism 41. When the innermost polygonal prism 41 is quadrilateral, the four reflecting surfaces 412 of the quadrilateral prism correspond to the four first laser chips 1, forming a quadrilateral annular spot composed of four light spots on the incident surface of the focusing lens group 5. The central region of this quadrilateral annular spot is a quadrilateral cavity. The number of second laser chips 2 can be relatively small. The collimated laser output directly passes through the through-hole 411, forming multiple parallel light spots on the incident surface of the focusing lens group 5. These parallel light spots are located inside the quadrilateral annular spot and are parallel to a pair of opposite parallel sides of the quadrilateral annular spot. This arrangement ensures that the parallel light spots in the central region are aligned with the quadrilateral annular spots on the periphery, which is beneficial to the overall uniformity and symmetry of the combined light spots.

[0052] When the innermost polygonal prism 41 is hexagonal, the six reflecting surfaces 412 of the hexagonal prism correspond to the six first laser chips 1, forming a hexagonal annular spot composed of six light spots on the incident surface of the focusing lens group 5. The central region of this hexagonal annular spot is a hexagonal cavity. Since the area of ​​the central region enclosed by the hexagonal annular spot is larger than that enclosed by the quadrilateral annular spot, the number of second laser chips 2 can be set relatively more to more fully fill the central region. The collimated laser output from the second laser chip 2 passes directly through the through-hole 411, forming multiple parallel light spots on the incident surface of the focusing lens group 5. These parallel light spots are located inside the hexagonal annular spot and are parallel to a pair of opposite parallel sides of the hexagonal annular spot. This arrangement ensures that the parallel light spots in the central region are aligned with the hexagonal annular spots on the periphery, which is beneficial to the overall uniformity and symmetry of the combined light spots.

[0053] Therefore, the number of second laser chips 2 is not fixed, but flexibly adjusted according to the number of sides of the innermost polygonal prism 41. The more sides the innermost prism has, the larger the area of ​​the central region it encloses, and the more second laser chips 2 can be accommodated. At the same time, the parallel light spots of the second laser chips 2 always remain parallel to a pair of parallel sides opposite each other in the annular light spot of the innermost prism, ensuring the coordination and consistency of the central light spot and the outer annular light spot in direction. This makes the overall outline of the combined light spot closer to a circle, further improving the utilization rate of the fiber numerical aperture and the uniformity of the light spot energy distribution.

[0054] In some embodiments, when the beam combining assembly 4 includes multiple polygonal prisms 41, the reflecting surfaces 412 on adjacent polygonal prisms 41 are offset radially. In the coaxial stacked structure of the multiple polygonal prisms 41, the reflecting surfaces 412 of each prism are located at the periphery of the through-hole 411, but at different radial positions. The reflecting surfaces 412 of the outer prism are located at a larger radius, and the reflecting surfaces 412 of the inner prism are located at a smaller radius. If the reflecting surfaces 412 of adjacent prisms overlap radially, that is, the inner radius of the outer reflecting surface 412 is smaller than the outer radius of the inner reflecting surface 412, the outer reflecting surface 412 will block the light beam refracted by the inner reflecting surface 412, causing the laser output from the inner first laser chip 1 to be unable to pass smoothly through the through-hole 411 after reflection, and part of the light beam is cut off by the outer reflecting surface 412, resulting in light energy loss and light spot distortion.

[0055] By offsetting the reflecting surfaces 412 of adjacent polygonal prisms 41 radially, the inner radius of the outer reflecting surface 412 is larger than the outer radius of the inner reflecting surface 412, and the two do not overlap radially. In this way, the light beam refracted by the inner reflecting surface 412 can pass unobstructed through the through-hole 411 region of the outer prism without being blocked by the outer reflecting surface 412. Simultaneously, the light beam refracted by the outer reflecting surface 412 is located at a larger radial position, spatially separated from the inner beam, and they do not interfere with each other.

[0056] With the above structure, multiple polygonal prisms 41 are coaxially stacked, with the number of sides of each prism decreasing sequentially from the outside to the inside. The reflecting surface 412 of the outer prism forms a ring-shaped light spot with a larger diameter, while the reflecting surface 412 of the inner prism forms a ring-shaped light spot with a smaller diameter. The ring-shaped light spots are nested sequentially from the outside to the inside, and the reflecting surfaces 412 of adjacent layers are staggered in the radial direction to avoid mutual occlusion. The second laser chip 2 is disposed on the optical axis G, and the laser output from it passes directly through the through hole 411 to form a central light spot. The number and arrangement of the second laser chips 2 are adapted to the number of sides of the innermost prism, so that the central light spot and the innermost ring-shaped light spot are consistent in direction. Through the coordinated operation of this multi-layered nested annular spot and the central spot, all lasers together form an approximately solid circular combined spot on the incident surface of the focusing lens group 5. The outline of this combined spot matches the circular receiving area defined by the numerical aperture of the output fiber S, which can fully fill the circular receiving area, thereby significantly improving the utilization rate of the fiber's numerical aperture, improving the uniformity of the spot energy distribution, and achieving efficient coupling of multiple lasers and maximizing the output power.

[0057] In some embodiments, the collimating optical component 3 includes a fast-axis collimating lens 31 and a slow-axis collimating lens 32. The fast-axis collimating lens 31 is attached to the light-emitting end face of the corresponding laser chip and is used to collimate the diverging light emitted by the laser chip in the fast-axis direction. Since the semiconductor laser chip has a large divergence angle in the fast-axis direction, the fast-axis collimating lens 31 can compress the diverging beam in this direction into an approximately parallel beam, thereby effectively controlling the beam size in the fast-axis direction. The slow-axis collimating lens 32 is disposed in the light-emitting direction of the fast-axis collimating lens 31 and is used to collimate the diverging light emitted by the laser chip in the slow-axis direction. The divergence angle of the laser chip in the slow-axis direction is relatively small, but it is still necessary to collimate it to further compress the beam size in the slow-axis direction. After the sequential collimation processing by the fast-axis collimating lens 31 and the slow-axis collimating lens 32, the diverging laser output by the laser chip is transformed into a narrow strip of light that is nearly parallel in both the fast and slow-axis directions.

[0058] The narrow beam pattern has a small cross-sectional size and a low divergence angle, which is beneficial for efficient coupling to the output fiber S after being folded by the beam combiner assembly 4 and focused by the focusing lens group 5. The fast-axis collimating mirror 31 is attached to the output end face of the laser chip, which can shorten the optical path to the maximum extent and reduce light energy loss. The slow-axis collimating mirror 32 is set independently, which can easily adjust its position and focal length according to actual needs to optimize the collimation effect in the slow axis direction. Through the cooperation of the fast-axis collimating mirror 31 and the slow-axis collimating mirror 32, the laser output from each laser chip is shaped into a narrow beam pattern of uniform size, which lays a good foundation for the uniform beam combining and efficient coupling of multiple lasers.

[0059] In some embodiments, the focusing lens group 5 is disposed in the output optical path of the beam combiner 4 to focus all the laser light passing through the through-hole 411 and couple it to the output optical fiber S. The laser light passing through the through-hole 411 includes multiple peripheral lasers refracted by the reflective surfaces 412 of each layer of polygonal prisms 41 and the central laser light directly output from the second laser chip 2. These lasers have formed a near-solid circular combined spot in space, consisting of multiple annular spots and a central spot. The focusing lens group 5 focuses this combined spot as a whole, converging it onto the core end face of the output optical fiber S, thereby achieving efficient coupling of multiple lasers to the optical fiber.

[0060] In one implementation, the focusing lens group 5 may include a fast-axis focusing lens and a slow-axis focusing lens. The fast-axis focusing lens is used to focus the laser in the fast-axis direction, and the slow-axis focusing lens is used to focus the laser in the slow-axis direction. Since the narrow strip of light formed by the laser output from the first laser chip 1 after collimation has different sizes and divergence angles in the fast-axis and slow-axis directions, using discrete fast-axis and slow-axis focusing lenses allows for independent focusing control in the two directions, ensuring that the focused light spot matches the numerical aperture of the fiber core at the fiber end face. The fast-axis and slow-axis focusing lenses can be arranged sequentially along the optical axis G, maintaining an appropriate distance between them to achieve the best focusing effect.

[0061] As another implementation, the focusing lens group 5 can employ a dual-focusing lens that simultaneously performs fast-axis and slow-axis focusing. The dual-focusing lens has different radii of curvature or aspherical surface shapes in two orthogonal directions, enabling simultaneous focusing of both the fast-axis and slow-axis components of the laser. Using a dual-focusing lens reduces the number of optical components, shortens the optical path length, and lowers the system's assembly complexity and cost. The design parameters of the dual-focusing lens need to be optimized based on the beam characteristics of the first laser chip 1 and the second laser chip 2, as well as the numerical aperture of the output fiber S, to ensure that the focused spot size and divergence angle meet the requirements of fiber coupling.

[0062] Regardless of whether discrete lenses or dual-focusing lenses are used, the focusing lens group 5 must ensure that all laser light passing through the through-hole 411 is accurately focused onto the core end face of the output fiber S, and that the size and numerical aperture of the focused spot match the receiving capability of the output fiber S. Through the precise focusing of the focusing lens group 5, the energy of multiple lasers can be concentrated and injected into the fiber, thereby achieving high-efficiency fiber coupling output.

[0063] In some embodiments, a substrate 6 is fixedly disposed on the outer periphery of the polygonal prism 41. The substrate 6 provides a stable mounting base for the first laser chip 1 and the corresponding collimating optical component 3. Since the first laser chip 1 is disposed on the outer periphery of the polygonal prism 41, and each first laser chip 1 needs to maintain a precise alignment relationship with each side of the polygonal prism 41, fixing the substrate 6 on the outer periphery of the polygonal prism 41 ensures that after the first laser chip 1 and the collimating optical component 3 are positioned and fixed on the surface of the substrate 6, their overall relative positions with the polygonal prism 41 remain consistent, thereby simplifying the assembly process and improving assembly accuracy.

[0064] In this embodiment, a cooling channel (not shown in the figure) is formed within the substrate 6. Multiple first laser chips 1 generate a large amount of heat during operation. If this heat cannot be dissipated in time, the laser chip temperature will rise, causing a decrease in output power, wavelength drift, or even chip damage. By forming a cooling channel within the substrate 6, a cooling medium can be introduced into the channel. As the cooling medium flows through the channel, it carries away the heat generated by the substrate 6 and the first laser chips 1 fixed thereon, achieving effective heat dissipation for the first laser chips 1. The cooling channel can be arranged along the extension direction of the substrate 6, covering the mounting area of ​​all first laser chips 1, ensuring uniform heat dissipation for each chip.

[0065] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A semiconductor laser coupling system, characterized in that, include: Multiple first laser chips and at least one second laser chip are used to output laser light; Multiple collimating optical components are provided, each of which is disposed in the output optical path of a first laser chip or a second laser chip, for collimating the laser output from the laser chip. A beam combining assembly includes at least one polygonal prism, wherein the central region of the polygonal prism has a through hole extending along the optical axis, and the periphery of the through hole has multiple reflective surfaces; the first laser chip is disposed on the outer periphery of the polygonal prism, and each of the reflective surfaces corresponds to one first laser chip, for refracting the collimated laser output from the first laser chip and passing it through the through hole; A focusing lens group is disposed in the output optical path of the beam combining assembly to focus the laser light passing through the through hole and couple it to the output optical fiber; The second laser chip is disposed on the optical axis of the beam combining assembly and located on the side away from the focusing lens group, and the collimated laser output from it passes directly through the through hole; When the beam combining assembly includes at least two layers of polygonal prisms, the polygonal prisms are coaxially stacked and have different numbers of sides, and the reflecting surfaces of each polygonal prism are distributed along different azimuth angles in a plane perpendicular to the optical axis, so that the outline of the combined light spot formed by all the lasers passing through the through hole on the incident surface of the focusing lens group matches the circular receiving area defined by the numerical aperture of the output optical fiber.

2. The semiconductor laser coupling system as described in claim 1, characterized in that: The polygonal prism has 2n sides, where n is an integer greater than or equal to 2.

3. The semiconductor laser coupling system as described in claim 1, characterized in that: Multiple first laser chips are evenly distributed around the outer periphery of the polygonal prism, and the light emission direction of each first laser chip is perpendicular to the side surface of the corresponding polygonal prism.

4. The semiconductor laser coupling system as described in claim 1, characterized in that: The reflecting surfaces of each polygonal prism are planes at a 45° angle to the optical axis, used to deflect the incident laser by 90°.

5. The semiconductor laser coupling system as described in claim 1, characterized in that: The aperture of the through hole is greater than or equal to the outer diameter of the combined spot of the collimated laser output from the second laser chip at the through hole.

6. The semiconductor laser coupling system as described in claim 2, characterized in that: When the beam combining assembly includes multiple polygonal prisms, the number of sides of each polygonal prism decreases sequentially from the side closest to the focusing lens group to the side furthest from the focusing lens group along the optical axis.

7. The semiconductor laser coupling system as described in claim 2, characterized in that: When the beam combining assembly includes multiple polygonal prisms, the reflecting surfaces on adjacent polygonal prisms are staggered in the radial direction.

8. The semiconductor laser coupling system as described in claim 1, characterized in that: The reflective surface of the polygonal prism is provided with a high-reflectivity film.

9. The semiconductor laser coupling system as described in claim 1, characterized in that: The collimating optical assembly includes a fast-axis collimating lens and a slow-axis collimating lens. The fast-axis collimating lens is attached to the light-emitting end face of the corresponding laser chip, and the slow-axis collimating lens is positioned in the light-emitting direction of the fast-axis collimating lens.

10. The semiconductor laser coupling system as described in claim 1, characterized in that: A substrate is fixedly disposed on the outer periphery of the polygonal prism, the first laser chip and the corresponding collimating optical component are fixedly disposed on the surface of the substrate, and a cooling channel is formed in the substrate.

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