Fast and slow axis compression rearrangement prism system for shaping and combining light beams of stack light source

Abstract

The present disclosure provides a fast and slow axis compression rearrangement prism system for stack light source beam shaping and combining, comprising: a collimation unit for collimating light beams generated by a laser stack light source, the laser stack light source comprising a first stack and a second stack, each stack comprising a plurality of micro strip lasers; the two-stage fast axis compression unit is used for compressing and rearranging light beam arrays among the plurality of micro strip-shaped lasers in each stack twice; the three-section slow axis rearrangement unit is used for translating the whole stacked light beam array in the slow axis direction, shifting the whole translated light beam array by the height of a complete fast axis light spot array in the fast axis direction, and translating the light beam array subjected to height shifting again in the slow axis direction to obtain a light beam array subjected to light spot rearrangement; the beam shrinking unit is used for compressing the beam waist size of the light beam array after the light spots are rearranged in the fast axis direction; and the focusing coupling unit is used for coupling the compressed light beam array into an optical fiber.

Description

Technical Field

[0001] This disclosure relates to the field of laser optics technology and can be applied to high-brightness, high-energy-density laser pumping or energy coupling applications. In particular, it relates to a fast and slow axis compression rearrangement prism system for beam shaping and combining of stacked light sources. Background Technology

[0002] With the widespread application of high-power lasers in laser pumping, laser cladding, and materials processing, edge-emitting semiconductor lasers are widely used as main laser sources or pump sources due to their high efficiency, long lifespan, and high integration. To achieve higher power density output, multiple mini-bar lasers are typically spatially stacked to form a vertical or horizontal array, creating a mini-bar stack light source.

[0003] Side-emitting semiconductor laser arrays not only have a significant beam parameter product (BPP) mismatch problem in the fast and slow axis directions, but also form obvious "dark areas" due to the regular arrangement gaps introduced by the stack structure itself, resulting in insufficient beam space filling rate and thus reducing the overall energy utilization efficiency. Summary of the Invention

[0004] In view of the above problems, this disclosure provides a fast and slow axis compression rearrangement prism system for beam shaping and combining of stacked light sources, in order to solve the above technical problems.

[0005] This disclosure provides a fast and slow axis compression rearrangement prism system for beam shaping and combining of a stacked laser source, comprising: a collimation unit for collimating the beam generated by the laser stacked source, wherein the laser stacked source includes a first stack and a second stack, each stack including multiple micro-strip lasers; a two-stage fast axis compression unit for compressing and rearranging the beam array between the multiple micro-strip lasers within each stack twice to reduce the beam spacing in the fast axis direction; and a three-stage slow axis rearrangement unit for translating the beam array of one of the first and second stacks along the slow axis direction, so that after translation... The beam array is brought close to another stacked beam array. The translated beam array is shifted along the fast axis by the height of a complete fast axis beam array. Then, the height-shifted beam array is translated again along the slow axis, so that the beam array corresponding to the second translated beam array is horizontally aligned and vertically stacked with the beam array corresponding to the other stacked beam array, resulting in a rearranged beam array. The beam shrinking unit is used to compress the beam waist size of the rearranged beam array along the fast axis, resulting in a compressed beam array. The focusing coupling unit is used to couple the compressed beam array into the optical fiber to achieve high-brightness energy transmission.

[0006] According to embodiments of this disclosure, the collimation unit includes a fast-axis collimating lens and a slow-axis collimating lens; the fast-axis collimating lens is a plano-convex aspherical cylindrical lens with cylindrical curvature along the fast-axis direction, used to collimate the diverging beam in the fast-axis direction; the slow-axis collimating lens is a plano-convex cylindrical lens with cylindrical curvature along the slow-axis direction, used to collimate the diverging beam in the slow-axis direction.

[0007] According to embodiments of this disclosure, the cylindrical directions of the fast-axis collimating lens and the slow-axis collimating lens are perpendicular to each other, and their optical working surfaces are orthogonal at 90°. In the collimation process, the fast-axis direction is collimated first, and then the slow-axis direction is collimated.

[0008] According to embodiments of this disclosure, the two-stage fast-axis compression unit includes a first compression structure and a second compression structure. The first compression structure is composed of multiple prism units stacked vertically, each prism unit including a V-shaped prism composed of two reflecting prisms. The first compression structure is used to compress the spacing between two adjacent rows of light spots in the fast-axis direction of the beam array. The second compression structure includes a V-shaped prism composed of two reflecting prisms, used to symmetrically translate two sets of light spots at the edge of the beam array towards the center of the beam array, compressing the spacing of the entire beam array in the fast-axis direction, and achieving a central axis symmetrical high-density arrangement.

[0009] According to embodiments of this disclosure, the three-segment slow-axis rearrangement unit is a three-segment structure consisting of a first translation structure, a second offset structure, and a third translation structure formed by three reflecting prisms connected in sequence. The first translation structure is used to translate the entire beam array of one of the first stacks and the second stacks along the slow axis direction, so that the translated beam array is close to the beam array of the other stack. The second offset structure is used to offset the entire translated beam array along the fast axis direction by the height of a complete fast-axis spot array. The third translation structure is used to translate the height-offset beam array again along the slow axis direction, so that the spot array corresponding to the beam array after the second translation is horizontally aligned and vertically stacked with the spot array corresponding to the beam array of the other stack.

[0010] According to embodiments of this disclosure, the reflecting prism is composed of bonded optical glass and includes multiple reflecting surfaces, each reflecting surface having a prism face angle of 45° or 135°.

[0011] According to embodiments of this disclosure, the beam-shrinking unit includes one of a Keplerian beam-shrinking system, a Galilean beam-shrinking system, and a biprism beam-shrinking system.

[0012] According to embodiments of this disclosure, a Galilean beam-shrinking system includes a Galilean cylindrical beam-shrinking system composed of plano-concave and plano-convex cylindrical lenses.

[0013] According to embodiments of this disclosure, the fast and slow axis compression rearrangement prism system satisfies the beam quality evaluation criteria:

[0014]

[0015]

[0016]

[0017]

[0018] The fast and slow axis compression rearrangement prism system also needs to meet the fiber optic coupling conditions:

[0019]

[0020]

[0021]

[0022] in, The beam parameter product is used to measure the quality of a laser beam. and These are the beam parameter products in the fast axis direction and the slow axis direction, respectively. Where is the core diameter of the optical fiber, NA is the numerical aperture of the optical fiber, and D is the spot diameter on the focusing plane. , These are the divergence half-angles of the beam along the fast and slow axes, respectively, after the focal length of the beam.

[0023] According to embodiments of this disclosure, the initial divergence angle in the fast axis direction is approximately 30° to 70°, the waist diameter in the fast axis direction is 0.3 μm to 2 μm, the divergence angle in the slow axis direction is approximately 6° to 14°, the waist diameter in the slow axis direction is 0.3 μm to 2 μm, the core diameter of the optical fiber is 50 μm to 1000 μm, and the numerical aperture is 0.12 to 0.3.

[0024] The fast and slow axis compression rearrangement prism system for beam shaping and combining of stacked light sources disclosed herein has at least the following technical effects:

[0025] This system employs a precision optical path rearrangement and spatial compression strategy to compress and fill "dark areas" along the fast and slow axes, and to reshape the beam. This achieves beam parameter product matching, improves beam space-filling rate and brightness uniformity, ultimately enabling efficient coupling to high numerical aperture fibers in a compact structure. The system is suitable for applications such as high-power pump lasers, high-brightness material processing, and energy coupling. Furthermore, it features excellent modularity, allowing for flexible expansion based on the number of minibars and compatibility with multi-stack laser structures. Attached Figure Description

[0026] The foregoing contents, as well as other objects, features, and advantages of this disclosure, will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0027] Figure 1 A schematic block diagram of a fast and slow axis compression prism system for efficient beam shaping and combining of a stacked light source, according to an embodiment of the present disclosure, is shown.

[0028] Figure 2 The diagram illustrates the optical path of a fast and slow axis compression prism system for efficient beam shaping and combining of a stacked light source according to an embodiment of the present disclosure.

[0029] Figure 3 The diagram schematically illustrates the fast and slow axis collimation structure and spot pattern of a stacked light source according to an embodiment of the present disclosure.

[0030] Figure 4 The schematic diagram shows a front view of a two-stage fast-axis compression system according to an embodiment of the present disclosure.

[0031] Figure 5 The schematic diagram illustrates the structural dimensions and optical path of a two-stage fast-axis compression system according to an embodiment of the present disclosure.

[0032] Figure 6 The diagram schematically illustrates a first compression structure and a light spot pattern according to an embodiment of the present disclosure.

[0033] Figure 7 The diagram schematically illustrates a second compression structure and a light spot pattern according to an embodiment of the present disclosure.

[0034] Figure 8 The diagram schematically shows a top view (left) and a front view (right) of a three-segment slow axis rearrangement unit according to an embodiment of the present disclosure.

[0035] Figure 9 The schematic diagram illustrates the structural dimensions and optical path of a three-segment slow axis rearrangement unit according to an embodiment of the present disclosure.

[0036] Figure 10 The diagram schematically illustrates the first translation structure and light spot pattern according to an embodiment of the present disclosure.

[0037] Figure 11 The diagram schematically illustrates the second segment offset structure and spot pattern according to an embodiment of the present disclosure.

[0038] Figure 12 The diagram schematically illustrates the third segment translation structure and light spot pattern according to an embodiment of the present disclosure.

[0039] Figure 13 A schematic diagram of a Galilean beam-shrinking system according to an embodiment of the present disclosure is shown.

[0040] Figure 14 A schematic diagram of a focusing coupling unit according to an embodiment of the present disclosure is shown.

[0041] Figure 15 The diagram illustrates the energy loss calculation results of each module of the fast and slow axis compression rearrangement prism system according to an embodiment of the present disclosure. Detailed Implementation

[0042] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0043] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of these embodiments. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0044] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0045] In the process of realizing this disclosure, it was discovered that edge-emitting lasers exhibit significant differences in optical characteristics along the fast and slow axes: The emission size along the fast axis (perpendicular to the active region plane, Y direction) is extremely small (typically less than 1 μm), and due to diffraction limitations, its initial divergence angle is relatively large, typically 30°–70° (1 / e² intensity definition). Using an aspherical fast-axis collimating lens (FAC) for collimation can compress the remaining divergence angle to within the range of 0.1°–0.3°. In contrast, the slow-axis direction (parallel to the active region plane, slow axis direction) has a larger emission size (typically 2 μm to 400 μm), and a relatively smaller initial divergence angle, generally 6° to 14° (1 / e² intensity definition). Although collimation can be achieved using a slow-axis collimating lens (SAC), due to the larger emission surface size, the remaining divergence angle after collimation is still relatively large, typically within the range of 0.3° to 3°, and the collimation effect is significantly inferior to that of the fast axis. The significant difference between the beam waist size and the remaining divergence angle after collimation along the fast and slow axes leads to a marked mismatch in the beam parametric product (BPP) in the two directions. This mismatch becomes a crucial factor limiting beam brightness enhancement and fiber coupling efficiency.

[0046] Because of the mechanical installation gaps between multiple minibar light sources vertically stacked within each stack, a regular "dark area" appears on the fast axis. Simultaneously, installation gaps also exist between different stacks in the horizontal direction, resulting in a large discontinuous "dark area" on the slow axis. This structural "dark area" leads to low beam space-filling ratio and uneven energy density distribution, severely limiting subsequent beam shaping and coupling efficiency improvements. Therefore, it is necessary to use optical structures to compress and fill the "dark areas" on both the fast and slow axes to meet the BPP matching conditions and improve fiber coupling efficiency and laser brightness.

[0047] To address the aforementioned issues, this disclosure presents a systematically optimized design. By implementing "dark area" compression and rearrangement shaping in both the fast and slow axis directions, the BPP matching degree in both axis directions can be significantly improved, ultimately achieving efficient fiber coupling output.

[0048] Figure 1 A schematic block diagram of a fast and slow axis compression prism system for efficient beam shaping and combining of a stacked light source, according to an embodiment of the present disclosure, is shown.

[0049] like Figure 1 As shown, a fast and slow axis compression prism system for efficient beam shaping and combining of stacked light sources may include a collimation unit, a two-stage fast axis compression unit, a three-stage slow axis rearrangement unit, a beam shrinking unit, and a focusing coupling unit.

[0050] The collimation unit is used to collimate the beam generated by the laser stack light source, wherein the laser stack light source includes a first stack and a second stack, and each stack includes multiple miniature strip lasers arranged vertically in sequence.

[0051] Two-stage fast-axis compression units are used to compress and rearrange the beam array between multiple micro-strip lasers within each stack twice to reduce the beam spacing in the fast-axis direction.

[0052] The three-segment slow-axis rearrangement unit is used to translate the beam array of one of the first and second stacks along the slow axis direction, so that the translated beam array is close to the beam array of the other stack. The translated beam array is then offset along the fast axis direction by the height of a complete fast-axis beam array. The beam array with the height offset is then translated again along the slow axis direction, so that the beam array corresponding to the beam array after the second translation is horizontally aligned and vertically stacked with the beam array corresponding to the beam array of the other stack, resulting in the beam array after beam rearrangement.

[0053] The beam-shrinking unit is used to compress the beam waist size of the rearranged beam array in the fast axis direction to obtain a compressed beam array.

[0054] The focusing coupling unit is used to couple the compressed beam array into the optical fiber to achieve high-brightness energy transmission.

[0055] Figure 2 The diagram illustrates the optical path of a fast and slow axis compression prism system for efficient beam shaping and combining of a stacked light source according to an embodiment of the present disclosure. Figure 3 The diagram schematically illustrates the fast and slow axis collimation structure and spot pattern of a stacked light source according to an embodiment of the present disclosure.

[0056] like Figure 2 and Figure 3 As shown, in some embodiments, the laser stack light source 1 may include a first stack 10 and a second stack 11, each stack including a plurality of miniature strip lasers.

[0057] The collimation unit may include a fast-axis collimating lens 2 (FAC) and a slow-axis collimating lens 3 (SAC). The fast-axis collimating lens 2 is a plano-convex aspherical cylindrical lens with cylindrical curvature along the fast axis, used to collimate the diverging beam in the fast-axis direction; the slow-axis collimating lens 3 is a plano-convex cylindrical lens with cylindrical curvature along the slow axis, used to collimate the diverging beam in the slow-axis direction. The fast-axis collimating lens 2 and the slow-axis collimating lens 3 can be arranged in front of the exit face of each stack of miniature strip lasers to compress the fast-axis large divergence angle beam and the slow-axis medium divergence angle beam, respectively, achieving preliminary collimation.

[0058] Furthermore, the cylindrical directions of the fast-axis collimating lens 2 and the slow-axis collimating lens 3 are perpendicular to each other, and their optical working surfaces are orthogonal at 90° during installation. During the collimation process, the fast-axis direction is collimated first, and then the slow-axis direction is collimated to effectively control the beam spread in the high divergence angle direction and achieve efficient shaping.

[0059] For example, the glass materials used for the fast-axis collimating lens 2 and the slow-axis collimating lens 3 include, but are not limited to: S-TIH53, N-BK7, H-K9L, H-ZF7L, SF11, and FGLASS2.

[0060] Figure 4 The schematic diagram shows a front view of a two-stage fast-axis compression system according to an embodiment of the present disclosure. Figure 5 The schematic diagram illustrates the structural dimensions and optical path of a two-stage fast-axis compression system according to an embodiment of the present disclosure. Figure 6 The diagram schematically illustrates a first compression structure and a light spot pattern according to an embodiment of the present disclosure. Figure 7 The diagram schematically illustrates a second compression structure and a light spot pattern according to an embodiment of the present disclosure.

[0061] like Figure 2 , Figures 4-7As shown, in some embodiments, the two-stage fast-axis compression unit 4 may include a first compression structure 40 and a second compression structure 41.

[0062] The first compression structure 40 is composed of multiple prism units stacked in a vertical direction. Each prism unit includes a V-shaped prism composed of two reflecting prisms. The first compression structure is used to compress the spacing between two adjacent rows of light spots in the fast axis direction of the beam array.

[0063] The second compression structure 41 includes a V-shaped prism composed of two reflecting prisms, which is used to symmetrically translate the two sets of light spots at the edge of the beam array towards the center of the beam array, compress the spacing of the entire beam array in the fast axis direction, and achieve a central axis symmetrical high-density arrangement.

[0064] For example, the first compression structure 40 includes reflective surfaces 402, 404, 405, 407 and transmissive surfaces 401, 403, 406, which are used to group and compress adjacent rows of mini bar light spots inside the stack, merge the central "dark area", and improve the center fill rate.

[0065] The second compression structure 41 may include reflective surfaces 411, 413, 415, and 417, and transmissive surfaces 410, 412, 414, and 416. This structure symmetrically shifts the light spots in the first, second, and penultimate rows of the array to the center of the dark area, further compressing the overall fast axis spacing and achieving a central axis symmetrical high-density arrangement.

[0066] Figure 8 The diagram schematically shows a top view (left) and a front view (right) of a three-segment slow axis rearrangement unit according to an embodiment of the present disclosure. Figure 9 The schematic diagram illustrates the structural dimensions and optical path of a three-segment slow axis rearrangement unit according to an embodiment of the present disclosure. Figure 10 The diagram schematically illustrates the first translation structure and light spot pattern according to an embodiment of the present disclosure. Figure 11 The diagram schematically illustrates the second segment offset structure and spot pattern according to an embodiment of the present disclosure. Figure 12 The diagram schematically illustrates the third segment translation structure and light spot pattern according to an embodiment of the present disclosure.

[0067] like Figure 2 , Figures 8-12 As shown, in some embodiments, the three-segment slow axis rearrangement unit 5 is a three-segment structure consisting of a first translation structure 50, a second offset structure 51, and a third translation structure 52, which are formed by connecting three reflecting prisms in sequence.

[0068] The first translation structure 50 is used to translate the beam array of one of the first stacks 10 and the second stack 11 along the slow axis direction, so that the translated beam array is closer to the beam array of the other stack.

[0069] The second offset structure 51 is used to offset the entire translated beam array along the fast axis direction by the height of a complete fast axis beam array.

[0070] The third translation structure 52 is used to translate the height-shifted beam array again along the slow axis direction, so that the beam array corresponding to the beam array after the second translation is horizontally aligned and vertically stacked with the beam array corresponding to another stack of beam arrays.

[0071] For example, the first translation structure 50 may include reflective surfaces 502 and 503 and transmissive surfaces 501 and 504, which cause the entire beam of the first stack 10 to move closer to the second stack 11 along the slow axis direction through reflection, thereby achieving compression of the dark area between the stacks.

[0072] The second offset structure 51 may include reflective surfaces 511 and 512, enabling the entire beam of the first stack 10 to be shifted up or down by the height of a beam array in the fast axis direction, providing space for the misalignment and merging of the beam array.

[0073] The third translation structure 52 may include reflective surfaces 522 and 523 and transmission surfaces 521 and 524, to achieve a second translation along the slow axis direction, so that the beam of the first stack 10 and the light spot of the second stack 11 are aligned in the slow axis direction, thereby completing the filling of the slow axis "dark area".

[0074] Furthermore, the reflecting prisms used in the two-stage fast-axis compression unit 4 and the three-stage slow-axis rearrangement unit 5 are made of bonded optical glass and contain multiple reflecting surfaces, with each reflecting surface having a prism face angle of 45° or 135°.

[0075] In some embodiments, the beam-shrinking unit includes one of a Keplerian beam-shrinking system, a Galilean beam-shrinking system, and a biprism beam-shrinking system.

[0076] Figure 13 A schematic diagram of a Galilean beam-shrinking system according to an embodiment of the present disclosure is shown.

[0077] like Figure 2 and Figure 13 As shown, a Galilean beam-shrinking system may include a Galilean cylindrical beam-shrinking system composed of plano-concave and plano-convex cylindrical lenses to further compress the fast-axis beam waist size and improve beam parametric product (BPP) matching.

[0078] Furthermore, the fast and slow axis compression rearrangement prisms satisfy the beam quality evaluation conditions:

[0079]

[0080]

[0081]

[0082] in, The beam parameter product is used to measure the quality of a laser beam. and These are the beam parameter products in the fast axis direction and the slow axis direction, respectively. NA is the core diameter of the optical fiber, and NA is the numerical aperture of the optical fiber. It is a divergent full angle (in milliradians). The diameter of the waist.

[0083] The fast and slow axis compression rearrangement prism system also satisfies the fiber coupling condition:

[0084]

[0085]

[0086]

[0087] D is the diameter of the light spot on the focusing plane. , These are the divergence half-angles of the beam along the fast and slow axes, respectively, after the focal length of the beam.

[0088] In some embodiments, the initial divergence angle in the fast axis direction is approximately 30° to 70° (1 / e²), the waist diameter in the fast axis direction is 0.3 μm to 2 μm, the divergence angle in the slow axis direction is approximately 6° to 14° (1 / e²), the waist diameter in the slow axis direction is 0.3 μm to 2 μm, the core diameter of the optical fiber is 50 μm to 1000 μm, and the numerical aperture is 0.12 to 0.3.

[0089] Figure 14 A schematic diagram of a focusing coupling unit according to an embodiment of the present disclosure is shown.

[0090] like Figure 2 and Figure 14 As shown, the focusing coupling unit can use a spherical or aspherical focusing lens. The shaped beam is precisely focused and coupled into the multimode fiber through the spherical or aspherical focusing lens to achieve high-brightness laser energy output.

[0091] Figure 15 The diagram illustrates the energy loss calculation results of each module of the fast and slow axis compression rearrangement prism system according to an embodiment of the present disclosure.

[0092] likeFigure 15 As shown, the energy consumption of each module unit is low.

[0093] To further illustrate the fast and slow axis compression rearrangement prism system for beam shaping and combining of stacked light sources provided in this disclosure, a specific embodiment is described below.

[0094] The specific implementation of this embodiment will be described in detail below with reference to the aforementioned figures, in conjunction with structural parameters and simulation results.

[0095] I. Light source configuration.

[0096] This embodiment uses a high-power semiconductor laser array with an operating wavelength of 808 nm as the laser stack light source, consisting of two vertically stacked mini-bar stacks. Each stack contains 8 mini-bars, with a slow-axis spacing of 8 mm between the two stacks; each mini-bar contains 5 laser chips arranged in a period of 500 μm, with a fast-axis spacing of 1.8 mm between the mini-bars. The initial fast-axis divergence angle is 50° (light intensity 1 / e). 2 (Definition) The active region thickness is 1µm; the initial divergence angle of the slow axis is 8° (light intensity 1 / e 2 (Definition), the width of the light-emitting area is 230 μm, and the system has a total of 80 laser chips, which are arranged in a regular array.

[0097] II. Beam collimation system.

[0098] To effectively shape the diverging beam along the fast and slow axes, a fast-axis collimating lens (FAC) and a slow-axis collimating lens (SAC) are placed in front of each stack. The FAC uses a plano-convex aspherical cylindrical lens with cylindrical curvature along the fast axis, a radius of curvature of 0.411 mm, an effective focal length of 0.5 mm, a back focal length of 0.16 mm, and is made of S-TIH53 glass. After collimation, the residual divergence angle along the fast axis is approximately 1.57 mrad. The SAC uses a plano-convex cylindrical lens array with cylindrical curvature along the slow axis, a radius of curvature of 1.925 mm, an effective focal length of 2.25 mm, a back focal length of 2 mm, and is also made of S-TIH53 glass. After collimation, the residual divergence angle along the slow axis is 5.584 mrad. The "dark areas" along the fast axis are spaced seven times at 1.2 mm intervals, and the "dark areas" along the slow axis are spaced 5.6 mm apart.

[0099] III. Compression Shaping System in the Fast Axis Direction.

[0100] To eliminate the "dark area" in the fast axis direction between mini bars inside the stack and improve the fast axis spot fill rate, a two-stage fast axis compression structure is set up.

[0101] The first-stage compression structure 40 uses a V-shaped cemented reflective prism to compress and splice the adjacent two rows of mini bar light spots to the dark area position in the middle of the array, including reflective surfaces 402, 404, 405, and 407, with the included angle of the prism reflective surfaces being 45° or 135°; at this time, the fast axis "dark area" interval becomes 3 2.4 mm intervals.

[0102] The second-stage compression structure 41 symmetrically shifts the light spots of the first, second, and penultimate rows of the array towards the center through a set of V-shaped prisms, further compressing the fast-axis spacing of the overall array. The reflecting surfaces are numbered 411, 413, 415, and 417. After the second fast-axis compression, the dark area spacing is 0.1 mm.

[0103] IV. Slow axis direction position rearrangement system.

[0104] To improve the light spot density in the slow axis direction and achieve the staggered splicing of the two stacks, a three-segment slow axis rearrangement system (number 5) was set up, consisting of three sets of cemented reflective prism structures.

[0105] The first translation structure 50 uses the reflecting surfaces 502 and 503 to translate the entire beam of the first stack along the slow axis towards the second stack, achieving initial compression of the "dark area" between the stacks; at this time, the interval of the slow axis "dark area" is reduced to 1.96 mm.

[0106] The second offset structure 51 shifts the entire beam along the fast axis by the height of a complete beam array through the reflecting surfaces 511 and 512; the spacing of the slow axis "dark area" remains unchanged.

[0107] The third translation structure 52 shifts the beam along the slow axis again through the reflecting surfaces 522 and 523, so that the two stacked beams are staggered and complementary in the slow axis direction, thus filling the 5.6 mm gap area.

[0108] After the above beam shaping, the product of the optical parameters along the fast and slow axes of the beam is matched:

[0109] BPP fast = (1 / 4) × 9.7 mm × 1.57 mrad ≈ 3.80 mm·mrad;

[0110] BPP slow = (1 / 4) × 2.4 mm × 5.584 mrad ≈ 3.35 mm·mrad.

[0111] V. Fast-axis beam contraction system.

[0112] To further reduce the beam waist size along the fast axis, an asymmetric cylindrical beam-shrinking system with a Galilean structure is employed, comprising one set of plano-convex cylindrical lenses and one set of plano-concave cylindrical lenses. The plano-convex cylindrical lenses have an effective focal length of 80 mm, the plano-concave cylindrical lenses have an effective focal length of 20 mm, the lens spacing is 67 mm, and the lens material is N-BK7. After beam shrinking, the fast axis divergence angle becomes 5.934 mrad, and the beam waist is compressed to 2.5 mm. The corresponding parametric product is:

[0113] BPP fast = (1 / 4) × 2.5 mm × 5.934 mrad ≈ 3.87 mm·mrad;

[0114] BPP slow = (1 / 4) × 2.6 mm × 5.584 mrad ≈ 3.63 mm·mrad.

[0115] VI. Focused Coupled Systems.

[0116] The shaped beam is focused into the optical fiber through an aspherical focusing lens with an effective focal length of 10 mm. The focused spot size is 170 μm × 156 μm. The divergence half-angle after fast-axis focusing is 7.8°, and the divergence half-angle after slow-axis focusing is 8.1°, both less than 12.7° (arcsin(0.22) = 12.7°). The spot diameter is less than the core diameter of 200 μm, which meets the requirements for optical fiber coupling.

[0117] VII. Efficiency and Performance Evaluation

[0118] The system is configured with a reflectivity of 0.5% for all transmissive surfaces and 99.5% for reflective surfaces; a peak optical power of 70W per chip, an incident power of 5.6kW, an output power of 4.66kW, and a beam coupling efficiency of 83.2%.

[0119] The system has a package size of 140 mm × 20 mm × 18 mm, a compact structure, and is suitable for modular integration.

[0120] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A fast and slow axis compression rearrangement prism system for beam shaping and combining of stacked light sources, characterized in that, include: The collimation unit is used to collimate the beam generated by the laser stack light source, wherein the laser stack light source includes a first stack and a second stack, and each stack includes multiple miniature strip lasers; Two-stage fast-axis compression units are used to compress and rearrange the beam array between multiple micro-strip lasers within each stack twice to reduce the beam spacing in the fast-axis direction. The three-segment slow-axis rearrangement unit is used to translate the beam array of one of the first stacks and the second stacks along the slow axis direction, so that the translated beam array is close to the beam array of the other stack. The translated beam array is then offset along the fast axis direction by the height of a complete fast-axis beam array. The beam array with the height offset is then translated again along the slow axis direction, so that the beam array corresponding to the beam array after the second translation is horizontally aligned and vertically stacked with the beam array corresponding to the beam array of the other stack, thus obtaining the beam array after beam rearrangement. The beam-shrinking unit is used to compress the beam waist size of the rearranged beam array in the fast axis direction to obtain a compressed beam array. The focusing coupling unit is used to couple the compressed beam array into the optical fiber to achieve high-brightness energy transmission.

2. The fast and slow axis compression rearrangement prism system according to claim 1, characterized in that, The collimation unit includes a fast-axis collimating lens and a slow-axis collimating lens; The fast-axis collimating lens is a plano-convex aspherical cylindrical lens with cylindrical curvature along the fast axis direction, used to collimate diverging beams in the fast axis direction; The slow-axis collimating lens is a plano-convex cylindrical lens with cylindrical curvature along the slow axis direction, used to collimate diverging beams in the slow axis direction.

3. The fast and slow axis compression rearrangement prism system according to claim 2, characterized in that, The cylindrical directions of the fast-axis collimating lens and the slow-axis collimating lens are perpendicular to each other, and their optical working surfaces are orthogonal at 90°. During the collimation process, the fast-axis direction is collimated first, and then the slow-axis direction is collimated.

4. The fast and slow axis compression rearrangement prism system according to claim 1, characterized in that, The two-stage fast-shaft compression unit includes a first compression structure and a second compression structure; The first compression structure is composed of multiple prism units stacked in a vertical direction. Each prism unit includes a V-shaped prism composed of two reflecting prisms. The first compression structure is used to compress the spacing between two adjacent rows of light spots in the fast axis direction of the beam array. The second compression structure includes a V-shaped prism composed of two reflecting prisms, which is used to symmetrically translate the two sets of light spots at the edge of the beam array towards the center of the beam array, compress the spacing of the entire beam array in the fast axis direction, and achieve a central axis symmetrical high-density arrangement.

5. The fast and slow axis compression rearrangement prism system according to claim 1, characterized in that, The three-segment slow axis rearrangement unit is a three-segment structure consisting of a first translation structure, a second offset structure, and a third translation structure, which are formed by connecting three reflecting prisms in sequence. The first translation structure is used to translate the beam array of one of the first stacks and the second stacks as a whole along the slow axis, so that the translated beam array is closer to the beam array of the other stack. The second offset structure is used to offset the entire translated beam array along the fast axis direction by the height of a complete fast axis beam array. The third translation structure is used to translate the height-shifted beam array again along the slow axis, so that the beam array corresponding to the beam array after the second translation is horizontally aligned and vertically stacked with the beam array corresponding to another stack of beam arrays.

6. The fast and slow axis compression rearrangement prism system according to claim 4 or 5, characterized in that, The reflecting prism is composed of bonded optical glass and includes multiple reflecting surfaces, each reflecting surface having a prism face angle of 45° or 135°.

7. The fast and slow axis compression rearrangement prism system according to claim 1, characterized in that, The beam-shrinking unit includes one of the following: Keplerian beam-shrinking system, Galilean beam-shrinking system, and biprism beam-shrinking system.

8. The fast and slow axis compression rearrangement prism system according to claim 7, characterized in that, The Galilean beam-constriction system is a Galilean cylindrical beam-constriction system composed of plano-concave and plano-convex cylindrical lenses.

9. The fast and slow axis compression rearrangement prism system according to claim 1, characterized in that, The fast and slow axis compression rearrangement prism system meets the beam quality evaluation criteria: The fast and slow axis compression rearrangement prism system also satisfies the fiber coupling condition: in, The diameter of the waist is [missing information]. It is a divergent full angle (in milliradians). The beam parameter product is used to measure the quality of a laser beam. and These are the beam parameter products in the fast axis direction and the slow axis direction, respectively. Where is the core diameter of the optical fiber, NA is the numerical aperture of the optical fiber, and D is the spot diameter on the focusing surface. , These are the divergence angles of the beam along the fast and slow axes, respectively, after the focal length of the beam.

10. The fast and slow axis compression rearrangement prism system according to claim 9, characterized in that, The initial divergence angle in the fast axis direction is approximately 30°~70°, the waist diameter in the fast axis direction is 0.3 μm~2 μm, the divergence angle in the slow axis direction is approximately 6°~14°, the waist diameter in the slow axis direction is 0.3 μm~2 μm, the core diameter of the optical fiber is 50 μm~1000 μm, and the numerical aperture is 0.12~0.3.

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