Laser spot compressor

Abstract

This invention belongs to the field of optical device technology and discloses a laser spot compressor, including a semiconductor laser that emits an incident laser a, which is divided into incident laser a1 and incident laser a2. Incident laser a1 is incident on a polarizing beam combiner. It also includes an orthographic prism with its incident and exit surfaces facing each other. A rotator is disposed on one side of the exit surface of the orthographic prism, and a reflector is disposed on the other side. Incident laser a2 is incident perpendicularly on the incident surface of the orthographic prism and exits from the exit surface. It then passes through the rotator and the reflector sequentially before entering the polarizing beam combiner. The polarizing beam combiner combines incident laser a1 and incident laser a2 and shapes them into an exit laser b. This invention, through an innovative spot compression method, can fold the slow-axis of the laser spot after fast-axis shaping and lamination, achieving the superposition of the slow-axis Gaussian laser beam into a flat-top beam, and folding the spot size to half of its original size.

Description

Technical Field

[0001] This utility model belongs to the field of optical device technology, and relates to laser beams, specifically a laser beam compressor. Background Technology

[0002] In recent years, lasers have been widely used in the processing field, especially in the areas of material engraving, cutting, and welding. To pursue excellent processing performance, semiconductor laser sources are developing towards higher power, smaller spot size, and longer beam waist. In this process, there is an urgent need to compress the beam spot. Existing technologies mostly achieve spot compression through fast-axis collimation, lens shaping, and lamination.

[0003] However, due to the fast and slow axis characteristics and Gaussian distribution characteristics of semiconductor laser beams, the spot size is often limited when coupled with high-power light sources, making it impossible to eliminate the Gaussian beam characteristics. This results in insufficient precision in material processing and a number of defects. Utility Model Content

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a laser spot compressor that can couple high-power light sources, eliminate the Gaussian characteristics of laser beams, and superimpose slow-axis Gaussian laser beams into flat-top beams, thereby folding the spot size to half of its original size.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a laser spot compressor, comprising a semiconductor laser, wherein the semiconductor laser emits an incident laser a having fast and slow axis characteristics and Gaussian distribution characteristics, the incident laser a being divided into incident laser a1 and incident laser a2, and the incident laser a1 being incident to a polarizing beam combiner. It also includes an orthographic prism, wherein the incident surface and the exit surface of the orthographic prism are arranged opposite to each other. A rotator for changing the polarization state of the laser is provided on one side of the exit surface of the orthographic prism, and a reflector for changing the direction of the light path is provided on the other side of the rotator. The incident laser a2 is perpendicularly incident on the incident surface of the orthographic prism and then exits from the exit surface without changing the direction of the light path of the incident laser a2. Then, it passes through the rotator and the reflector in sequence and is then incident on the polarizing beam combiner. The polarization beam combiner combines the incident laser a1 and incident laser a2, and then shapes them into the outgoing laser b.

[0006] Furthermore, the side lengths of the incident and exit surfaces of the rhombic prism are greater than the beam width of the incident laser a2.

[0007] Furthermore, the incident laser a is compressed and collimated in lamination, with the slow axis direction denoted as AD. The positions of A and D are the two sides of the Gaussian beam, and the middle of the Gaussian beam is denoted as BC. The incident laser a1 is the AB segment beam, and the incident laser a2 is the CD segment beam.

[0008] The laser spot compression process of this invention is as follows: After incident laser a enters the device, incident laser a1 with a slow axis dimension AB maintains its original optical path direction, while incident laser a2 with a slow axis dimension CD is incident perpendicularly onto the incident surface of the rhomboid prism. After two reflections by the rhomboid prism, it exits parallel to incident laser a1. It then passes perpendicularly through a rotator to change the polarization state of incident laser a2, and then through a mirror to change the optical path direction of incident laser a2 to be perpendicular to the optical path direction of incident laser a1. Finally, after passing through a polarizing beam combiner, incident laser a1 and incident laser a2 with different polarization states are combined into an outgoing laser b. The fast axis dimension of outgoing laser b remains EF, but the slow axis dimension is halved due to the overlap of segments AB and CD in the slow axis direction.

[0009] Compared with the prior art, the beneficial effects of this utility model are: This invention, through an innovative spot compression method, can fold the slow-axis of the spot after fast-axis shaping and lamination, thereby superimposing the slow-axis Gaussian laser beam into a flat-top beam and folding the spot size to half of its original size.

[0010] The new laser beam obtained by this invention improves the relative irradiation intensity, and can achieve higher processing speed, cleaner cuts and sharper edges when laser processing the same material, making the processing more advantageous. Attached Figure Description

[0011] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0012] Figure 1 This is a schematic diagram of the optical path compression of this utility model.

[0013] Figure 2 This is a schematic diagram showing the spot size and irradiance of the incident laser a.

[0014] Figure 3 This is a cross-sectional view of the incident laser beam a.

[0015] Figure 4 This is a cross-sectional view of the emitted laser beam b.

[0016] In the diagram: 1-Oblique prism, 2-Optical rotator, 3-Reflector, 4-Polarizing beam combiner. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Example: Reference Figure 1-4 The laser beam compressor shown includes a semiconductor laser, which emits an incident laser a with fast and slow axis characteristics and Gaussian distribution characteristics. The incident laser a is divided into incident laser a1 and incident laser a2. Incident laser a1 is incident to a polarizing beam combiner 4. It also includes an orthorhombic prism 1, with the incident surface and the exit surface of the orthorhombic prism 1 arranged opposite each other. A rotator 2 for changing the polarization state of the laser is arranged on one side of the exit surface of the orthorhombic prism 1, and a reflector 3 for changing the direction of the light path is arranged on the other side of the rotator 2. The incident laser a2 is perpendicularly incident on the incident surface of the orthorhombic prism 1 and then exits from the exit surface without changing the direction of the light path of the incident laser a2. Then, it passes through the rotator 2 and the reflector 3 in sequence and is then incident on the polarizing beam combiner 4. The polarization combiner 4 combines the incident laser a1 and incident laser a2 into an outgoing laser b.

[0019] like Figure 1 As shown, the side length of the rhomboid prism 1 is greater than the beam width of the incident laser a2. The side lengths of the incident and exit surfaces of the rhomboid prism 1 are also greater than the beam width of the incident laser a2. Specifically, when the incident laser a2 irradiates the rhomboid prism 1, the areas of both the incident and exit surfaces of the rhomboid prism 1 are larger than the beam area of ​​the incident laser a2, allowing the entire incident laser a2 to enter the rhomboid prism 1. Furthermore, the incident laser a2 enters perpendicularly to the incident surface, undergoes two refractions, and exits perpendicularly to the exit surface.

[0020] like Figure 1-3 As shown, the incident laser a is compressed and collimated in a laminate, with the slow axis direction denoted as AD. The positions of A and D are the two sides of the Gaussian beam, and the middle of the Gaussian beam is denoted as BC. The incident laser a1 is the AB segment beam, and the incident laser a2 is the CD segment beam.

[0021] Please see Figures 1-4 The compression process of a laser spot compressor is as follows: After incident laser a enters the device, incident laser a1 with a slow axis dimension AB maintains its original optical path direction, while incident laser a2 with a slow axis dimension CD is incident perpendicularly onto the incident surface of the rhomboid prism 1. After two reflections by the rhomboid prism 1, it exits parallel to the incident laser a1. It then passes perpendicularly through the optical rotator 2 to change the polarization state of the incident laser a2, and then through the reflector 3 to change the optical path direction of the incident laser a2 to be perpendicular to the optical path direction of the incident laser a1. Finally, after passing through the polarization combiner 4, the incident laser a1 and the incident laser a2 with different polarization states are combined into an outgoing laser b. The fast axis dimension of the outgoing laser b remains EF, but the slow axis dimension is halved due to the overlap of segments AB and CD in the slow axis direction. Specifically, positions A and C of the slow axis dimension coincide, and positions B and D coincide. After superposition, the Gaussian beam forms a flat-top beam, and the relative irradiance is also improved.

[0022] In the use of the above laser spot compressor, the fast axis direction can be pre-designed by adjusting the collimation and lamination quantity to determine the ratio of the fast axis to the slow axis size of the entire beam. Then, the laser spot compressor is used to shape the beam into a square flat-top beam, which can achieve the same excellent processing effect in both lateral and longitudinal movements during laser processing.

[0023] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A laser spot compressor, comprising a semiconductor laser, said semiconductor laser emitting an incident laser a having fast and slow axis characteristics and a Gaussian distribution characteristic, said incident laser a being divided into incident laser a1 and incident laser a2, characterized in that: The incident laser a1 is incident on the polarization beam combiner (4). It also includes an orthorhombic prism (1), the incident surface and the exit surface of the orthorhombic prism (1) are arranged opposite to each other, a rotator (2) for changing the polarization state of the laser is provided on one side of the exit surface of the orthorhombic prism (1), and a reflector (3) for changing the direction of the light path is provided on the other side of the rotator (2). The incident laser a2 is perpendicularly incident on the incident surface of the orthorhombic prism (1) and then exits from the exit surface without changing the direction of the light path of the incident laser a2. Then it passes through the rotator (2) and the reflector (3) in sequence and is then incident on the polarization beam combiner (4). The polarization combiner (4) combines the incident laser a1 and the incident laser a2 and shapes them into the outgoing laser b.

2. The laser spot compressor according to claim 1, characterized in that: The side lengths of the incident and exit surfaces of the rhombic prism (1) are greater than the spot width of the incident laser a2.

3. The laser spot compressor according to claim 2, characterized in that: The incident laser a is compressed and collimated in a laminate, with the slow axis direction denoted as AD. The positions of A and D are the two sides of the Gaussian beam, and the middle of the Gaussian beam is denoted as BC. The incident laser a1 is the AB segment beam, and the incident laser a2 is the CD segment beam.

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