Fast and slow axis beam shaping method for novel laser bar packaging structure

Abstract

The invention discloses a fast and slow axis beam shaping method for a novel laser bar packaging structure, and the method comprises the steps: designing a bar packaging structure in the shape of a regular triangular prism, carrying out the collimation and beam expansion of a beam in a fast axis direction through employing an aspherical homogenizing lens, and carrying out the shaping of a beam in a slow axis direction; adjusting the fast-axis light beam with the divergence angle greater than a preset threshold value into a light beam parallel to or less than the divergence angle of the preset threshold value, and maintaining the energy distribution uniformity of the light beam at the same time; and then the light beams in the slow axis direction are segmented and superposed by using a micro-cylindrical lens array to finish the shaping of the light beams in the fast and slow axes. By implementing the packaging structure and the optical shaping method, the heat dissipation efficiency and the light beam quality of the high-power semiconductor laser can be effectively improved.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor laser packaging structures and optical shaping, and particularly relates to a method for fast and slow axis beam shaping for a novel laser bar strip packaging structure. Background Art

[0002] With the continuous development of semiconductor laser technology, its applications in fields such as industrial processing are becoming increasingly widespread. With the gradual deepening of applications, higher requirements are put forward for the peak power of semiconductor lasers. Therefore, bar strip arrays are adopted to increase the power upper limit.

[0003] However, there are many deficiencies in the packaging and optical shaping of high-power semiconductor lasers in the prior art. Most of the existing semiconductor laser packaging structures adopt the method of direct heat conduction and dissipation by a heat sink. When the power demand of the laser is high and the bar strips are arranged densely, this heat dissipation method cannot provide sufficient heat dissipation efficiency. For example, in high-power lasers, when the bar strips are stacked densely and the duty cycle is large, heat cannot be dissipated in time, resulting in a decline in the performance of the laser or even damage. And the traditional packaging structure design is relatively single and cannot meet the requirements of high-power and small-volume lasers. In the industrial and medical fields, the volume and weight of the laser are important considerations, while the existing packaging structures often have difficulty in both high-power output and compact design.

[0004] At the same time, the existing optical shaping schemes usually adopt gratings or multi-layer prisms. Although these schemes can improve the beam quality to a certain extent, their volumes are large and it is difficult to meet the requirements of small-volume lasers in the industrial and medical fields. And the existing optical shaping methods often cannot effectively solve the problem of uneven beam quality when dealing with fast and slow axis beams. For example, the beam divergence angle in the fast axis direction is large, while the beam intensity distribution in the slow axis direction is uneven, resulting in poor overall beam quality and affecting the application effect of the laser. Summary of the Invention

[0005] The present invention aims to solve the problems of insufficient heat dissipation efficiency of the existing semiconductor laser packaging structure and the large volume and uneven beam quality of the optical shaping scheme. By proposing a novel bar strip packaging structure and its fast and slow axis beam shaping method, the heat dissipation efficiency and beam quality of the laser are improved, while meeting the requirements of small volume and high power of lasers in the industrial and medical fields.

[0006] To achieve the above object, the present invention provides a method for fast and slow axis beam shaping for a novel laser bar strip packaging structure, including:

[0007] Design a bar strip packaging structure in the shape of a regular triangular prism, using an aspheric homogenizing lens to collimate and expand the light beam in the fast axis direction, adjust the fast axis light beam with a divergence angle greater than the preset threshold to a parallel beam or a beam with a divergence angle less than the preset threshold, and at the same time maintain the energy distribution uniformity of the light beam; then use a microlens array to split and superpose the light beam in the slow axis direction to complete the shaping of the fast and slow axis light beams.

[0008] Preferably, the process of designing the bar strip packaging structure in the shape of a regular triangular prism includes:

[0009] Adopt the structure of a regular triangular prism, with the base being a hollow heat sink in the shape of a regular triangular prism, and evenly place the bar strips on the three inner side walls of the triangular prism-shaped heat sink;

[0010] And arrange electrode plates between the bar strips, and set insulating plates between the bar strips and the heat sink base;

[0011] Set grooves at the welded joints of the electrodes and the insulating plates; wherein, the grooves are used to hold the excess solder;

[0012] Set several water-vapor mixed cooling channels at the center of the triangular prism, and cool the bar strips through the water-vapor mixed cooling channels.

[0013] Preferably, the aspheric homogenizing lens designs the shape and parameters of the aspheric surface through the ray tracing method.

[0014] Preferably, the aspheric homogenizing lens adopts a single aspheric lens or a combination of multiple aspheric lenses, and determines the lens position and lens parameters according to actual needs.

[0015] Preferably, the material of the aspheric homogenizing lens includes optical glass or quartz glass.

[0016] Preferably, the process of using the microlens array to split and superpose the light beam in the slow axis direction includes:

[0017] Split the incident light beam into several sub-beams. After each sub-beam is focused and shaped by the microlens, it is superposed on the target surface, and the arrangement mode and focal length parameters of the microlens are adjusted according to the splitting and superposition effect to obtain a superposed light spot with uniform light intensity distribution in the slow axis direction.

[0018] Preferably, the microlens array includes several microlenses;

[0019] The size and spacing of the microlenses are designed according to the beam characteristics of the semiconductor laser and the requirements of the target light spot.

[0020] Preferably, the microlens array adopts glass or plastic materials;

[0021] The micro-lens array is obtained by manufacturing through a processing or injection molding process.

[0022] Preferably, the method further includes arranging a polarization beam splitter in the optical path structure.

[0023] Preferably, the polarization beam splitter includes a first polarization beam splitter and a second polarization beam splitter;

[0024] The fast and slow axis light beams with perpendicular polarization directions are split by the first polarization beam splitter, and then the fast and slow axis light beams are respectively subjected to shaping processing;

[0025] The shaped fast and slow axis light beams are recombined through an optical element by the second polarization beam splitter, and a shaped target light beam is output.

[0026] Compared with the prior art, the present invention has the following advantages and technical effects:

[0027] The present invention proposes a new bar strip packaging structure. While ensuring sufficient output power, a water-vapor mixed cooling method is adopted to improve the heat dissipation efficiency; and aiming at the problem of uneven quality of the fast and slow axes of the light beam, a beam shaping method combining an aspherical lens and a micro-lens array is proposed to improve the light output quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings constituting a part of this application are used to provide a further understanding of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation to this application. In the drawings:

[0029] Figure 1 is a schematic diagram of the beam shaping method according to an embodiment of the present invention;

[0030] Figure 2 is a schematic diagram of the bar strip packaging structure in the shape of a regular triangular prism designed according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will refer to the drawings and combine the embodiments to detail this application.

[0032] It should be noted that the steps shown in the flowchart of the drawings can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order from that here.

[0033] Embodiment 1

[0034] As Figure 1-2As shown in the figure, in this embodiment, a method for shaping fast and slow axis beams for a new type of laser bar strip packaging structure is provided, including:

[0035] Design a bar strip packaging structure in the shape of a regular triangular prism, and use an aspherical homogenizing lens to collimate and expand the beam in the fast axis direction, adjust the fast axis beam with a divergence angle greater than a preset threshold to a parallel beam or a beam with a divergence angle less than the preset threshold, and at the same time maintain the energy distribution uniformity of the beam; then use a microlens array to divide and stack the beam in the slow axis direction to complete the shaping of the fast and slow axis beams.

[0036] Further, the process of designing the bar strip packaging structure in the shape of a regular triangular prism includes:

[0037] Adopt the structure of a regular triangular prism, with the base being a hollow heat sink in the shape of a regular triangular prism, and evenly place the bar strips on the three inner side walls of the triangular prism-shaped heat sink;

[0038] And set electrode plates between the bar strips, and set insulating plates between the bar strips and the heat sink base to prevent short circuits between the electrodes;

[0039] Set grooves at the welded joints of the electrodes and the insulating plates; among them, the grooves are used to hold excess solder to avoid solder overflow affecting the packaging quality;

[0040] Set several water-gas mixed cooling channels in the center of the triangular prism to cool the bar strips through the water-gas mixed cooling channels.

[0041] Further optimized solution, in this embodiment:

[0042] The heat sink base is made of an aluminum alloy material with high thermal conductivity to ensure good heat dissipation performance.

[0043] The insulating plate is made of polyimide film, which has good insulation performance and high temperature resistance characteristics.

[0044] The electrode plate is made of copper material, which has good electrical conductivity and thermal conductivity.

[0045] The bar strips are made of high-efficiency semiconductor laser materials, such as GaAs-based materials.

[0046] Even further optimized solution, the heat sink is processed by precision machining to manufacture a hollow heat sink in the shape of a regular triangular prism, and multiple water-gas mixed cooling channels are machined in its center.

[0047] When installing the insulating plate, cut the polyimide film into appropriate sizes and install it between the heat sink base and the bar strips.

[0048] The bar strips are evenly distributed on the three inner walls of the heat sink. Electrode sheets are installed between each bar strip and connected to the insulation plate by welding. During the welding process, the grooves are used to receive excess solder to ensure welding quality.

[0049] The cooling channel connection ensures smooth circulation of coolant and air flow by connecting the water-air mixed cooling channel to the external cooling system.

[0050] Specifically, the water-air mixed cooling passage uses the high specific heat capacity of water and the rapid heat dissipation characteristics of airflow to effectively cool the densely arranged bars. This cooling method can significantly improve the heat dissipation efficiency and ensure the stability of the laser when operating at high power.

[0051] Furthermore, this embodiment designs the above-mentioned packaging structure as a modular unit for modular packaging. In this way, it can be flexibly combined according to actual power requirements. For example, after arranging 6 to 8 packaging modules, a peak power of 500W can be achieved, and the heat dissipation effect is good and there is no abnormality. After combining the above-mentioned packaging method and optical shaping scheme, the average proportion of the cladding energy output in the optical fiber core layer is 63%, which is smaller than the traditional grating shaping and multi-layer prism shaping modules.

[0052] Furthermore, the shape and parameters of the aspheric surface of the aspheric homogenizing lens are designed by a ray tracing method.

[0053] Furthermore, the aspheric homogenizing lens adopts a single aspheric lens or a combination of multiple aspheric lenses, and the lens position and lens parameters are determined according to actual needs.

[0054] Furthermore, the material of the aspherical homogenizing lens includes optical glass or quartz glass.

[0055] Furthermore, this embodiment adopts an aspheric homogenizing lens for shaping in the fast axis direction, and designs the shape and parameters of the aspheric surface by ray tracing. The lens can collimate and expand the light beam in the fast axis direction, adjust the fast axis light beam with a large divergence angle to a relatively parallel light beam or a light beam with a certain divergence angle, and maintain the uniformity of the energy distribution of the light beam. The aspheric homogenizing lens can adopt a single lens or a combination of multiple lenses, and its position and parameters are determined according to actual needs. When selecting a lens, the lens material should be selected with good optical properties and transmittance, such as optical glass or quartz glass.

[0056] As a further optimization scheme, in this embodiment, when installing the lens, an aspheric homogenizing lens is installed in the optical path, and its position and angle are adjusted to ensure that the light beam in the fast axis direction is collimated and expanded.

[0057] Furthermore, the process of using the micro-cylindrical lens array to split and superimpose the light beams in the slow axis direction includes:

[0058] The incident light beam is split into a number of sub - light beams. After each sub - light beam is focused and shaped by a micro - cylindrical lens, they are superimposed on the target surface. Then, the arrangement pattern and focal length parameters of the micro - cylindrical lenses are adjusted according to the splitting and superimposing effect, so as to obtain a superimposed light spot with a uniform light intensity distribution in the slow - axis direction.

[0059] Furthermore, the micro - cylindrical lens array includes a number of micro - cylindrical lenses;

[0060] The size and spacing of the micro - cylindrical lenses are designed according to the beam characteristics of the semiconductor laser and the requirements of the target light spot.

[0061] Furthermore, the micro - cylindrical lens array is made of glass or plastic materials;

[0062] The micro - cylindrical lens array is obtained through processing or injection - molding processes.

[0063] In a further optimized solution, when installing the lens array in this embodiment, the micro - cylindrical lens array is installed in the optical path, and its arrangement pattern, focal length and other parameters are adjusted to ensure the splitting and superimposing of the light beam in the slow - axis direction, so as to form a uniform light spot.

[0064] By implementing the above - mentioned packaging structure and optical shaping method, this embodiment can effectively solve the defects of the prior art, improve the heat - dissipation efficiency and beam quality of high - power semiconductor lasers, and meet the requirements of the industrial and medical fields for small - volume, high - power lasers.

[0065] Furthermore, the method also includes setting a polarization beam splitter in the optical path structure.

[0066] Furthermore, the polarization beam splitter includes a first polarization beam splitter and a second polarization beam splitter;

[0067] The fast - and slow - axis light beams with perpendicular polarization directions are split by the first polarization beam splitter, and then the fast - and slow - axis light beams are respectively subjected to shaping processing;

[0068] The shaped fast - and slow - axis light beams are recombined through optical elements by the second polarization beam splitter to output the shaped target light beam.

[0069] This embodiment adopts a packaging structure with a water - vapor mixed cooling path, which can effectively solve the heat - dissipation problem of high - power lasers. In actual tests, after arranging 6 - 8 packaging modules, a peak power of 500W can be achieved, and the heat - dissipation effect is good without any abnormality.

[0070] The beam shaping method of this embodiment combines an aspherical lens and a microlens array, which can significantly improve the quality of the fast and slow axis beams. The average proportion of the output cladding energy of the shaped beam in the fiber core layer is 63%, and it has a smaller volume than the traditional grating shaping and multi-layer prism shaping modules, making it more suitable for the requirements of small volume and high power lasers in the industrial and medical fields.

[0071] This embodiment also has the advantage of modular design. The modular design of the packaging structure enables the power of the laser to be flexibly adjusted according to actual needs, while facilitating production and maintenance and reducing the manufacturing cost.

[0072] Embodiment 2

[0073] This embodiment also discloses a computer device, including a memory, a processor, and a computer program stored on the memory. The processor executes the computer program to implement the steps of the method described in Embodiment 1.

[0074] Embodiment 3

[0075] This embodiment also discloses a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the steps of the method described in Embodiment 1.

[0076] Embodiment 4

[0077] This embodiment also discloses a computer program product, including a computer program. When the computer program is executed by a processor, it implements the steps of the method described in Embodiment 1.

[0078] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A fast and slow axis beam shaping method for a new laser bar packaging structure, characterized in that: include: A bar packaging structure in the shape of a regular triangular prism is designed, and an aspheric homogenizing lens is used to collimate and expand the light beam in the fast axis direction, and adjust the fast axis light beam with a divergence angle greater than a preset threshold to a beam with a divergence angle parallel to or less than the preset threshold, while maintaining the uniformity of the light beam energy distribution; then a micro-column lens array is used to split and superimpose the light beam in the slow axis direction to complete the fast and slow axis beam shaping.

2. The method according to claim 1, characterized in that The process of designing a bar package structure in the shape of a regular triangular prism includes: The structure of a regular triangular prism is adopted, the base is a regular triangular prism-shaped hollow heat sink, and the bar strips are evenly placed on the three inner walls of the triangular prism-shaped heat sink; and arranging electrode sheets between the bar strips, and arranging insulating plates between the bar strips and the heat sink base; A groove is provided at the place where the electrode and the insulating plate are welded together; wherein the groove is used to receive excess solder; A plurality of water-gas mixing cooling passages are arranged at the center of the triangular prism, and the bar strips are cooled through the water-gas mixing cooling passages.

3. The method according to claim 1, characterized in that The shape and parameters of the aspheric surface of the aspheric homogenizing lens are designed by a ray tracing method.

4. The method according to claim 1, characterized in that: The aspheric homogenizing lens adopts a single aspheric lens or a combination of multiple aspheric lenses, and the lens position and lens parameters are determined according to actual needs.

5. The method according to claim 1, characterized in that: The material of the aspherical homogenizing lens includes optical glass or quartz glass.

6. The method according to claim 1, characterized in that The process of using a micro-cylindrical lens array to split and superimpose the light beam in the slow axis direction includes: The incident light beam is divided into several sub-beams, each of which is focused and shaped by a micro-cylindrical lens and then superimposed on the target surface. The arrangement mode and focal length parameters of the micro-cylindrical lens are adjusted according to the division and superposition effects to obtain a superimposed light spot with uniform light intensity distribution in the slow axis direction.

7. The method according to claim 1, characterized in that The micro-column lens array includes a plurality of micro-column lenses; The size and spacing of the micro-column lenses are designed according to the beam characteristics of the semiconductor laser and the target spot requirements.

8. The method according to claim 1, characterized in that: The micro-column lens array is made of glass or plastic material; The micro-column lens array is manufactured by machining or injection molding.

9. The method according to claim 1, characterized in that: The method also includes providing a polarization beam splitter in the optical path structure.

10. The method according to claim 9, characterized in that The polarization beam splitter includes a first polarization beam splitter and a second polarization beam splitter; Splitting the fast-axis and slow-axis light beams whose polarization directions are perpendicular to each other through the first polarization beam splitter, and then shaping the fast-axis and slow-axis light beams respectively; The fast and slow axis light beams shaped by the second polarization beam splitting are combined by an optical element to output a shaped target light beam.

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