A detachable micro-channel semiconductor bar fiber laser module and a packaging method thereof

Abstract

This invention relates to a detachable microchannel semiconductor bar fiber laser module and its packaging method, belonging to the field of semiconductor laser packaging technology. The module includes a housing, a cover plate, a stacked array, a VBG grating, a slow-axis collimating lens, a reflector, a polarization beam combiner, a protective lens, a coupling module, and an optical fiber. The housing is a hollow cuboid structure with a cover plate on its upper side. A lens fixing step is located on one side of the housing, and stacked array fixing steps are symmetrically arranged on both sides of the lens fixing step. A stacked array is mounted on the stacked array fixing steps. A VBG grating and a slow-axis collimating lens are sequentially mounted on the lens fixing step on the light-emitting side of the stacked array. A reflector is located at the center of the stacked array fixing step. A polarization beam combiner corresponding to the reflector is located on the other side of the housing. A protective lens and a coupling module are sequentially mounted on the other side of the polarization beam combiner. An optical fiber is externally connected to the coupling module. This invention features a simple structure, convenient assembly and maintenance, good heat dissipation, and stable performance.

Description

TECHNICAL FIELD

[0001] The application relates to a detachable micro-channel semiconductor bar fiber laser module and a packaging method thereof, and belongs to the technical field of semiconductor laser packaging. BACKGROUND

[0002] Due to the advantages of small volume, light weight, high electro-optical conversion efficiency, long service life and high reliability, semiconductor lasers have gradually replaced the use of gas and solid lasers in the fields of communication, medical treatment, display, industrial production and security, and their application range is gradually expanding. The various advantages of semiconductor lasers determine that they are increasingly valued by all sectors of society. With the progress of semiconductor laser packaging technology, the packaging form and product structure of semiconductor lasers are more and more diversified. As the third generation of lasers, fiber lasers have the advantages of good beam quality, ultra-high conversion efficiency, high stability, small size and the like, and their development speed is getting faster and faster.

[0003] At present, common fiber lasers on the market mainly include single-chip semiconductor fiber lasers and multi-chip semiconductor fiber lasers. For example, a packaging structure of a semiconductor laser array is disclosed in Chinese patent document CN110518453A. Whether it is a single-chip or a multi-chip fiber laser, the packaging structure basically adopts the method of sintering the laser chip to the heat sink to form a COS, and then sintering or pasting the COS into the fiber laser shell to form a whole with the shell. The packaging structure is relatively complex and has many drawbacks. The fiber laser packaging process needs to go through dozens of processes, and it is inevitable that the laser will fail during the production process, resulting in the scrapping of the entire fiber laser and causing great losses.

[0004] At the same time, the heat dissipation mode of the fiber laser with the structure is that the heat generated by the laser is transferred to the heat dissipation water cooling plate through the heat sink and the shell, or is directly dissipated by the fan, and the heat dissipation effect is relatively poor, which greatly limits the power of the laser. The power of the laser is generally only tens of watts or hundreds of watts. However, with the increase of the power of the laser, the heat generated by the laser increases, which leads to a sharp rise in the temperature of the laser, affecting the stability of the wavelength, power and other parameters of the laser and the service life of the laser. Therefore, a fiber laser module structure and packaging method with simple structure, good heat dissipation, convenient maintenance and repair, high production efficiency, low production cost, stable performance and higher power are needed to solve the problems existing in the current fiber lasers. SUMMARY

[0005] In view of the deficiencies of the prior art, the application provides a detachable micro-channel semiconductor bar fiber laser module, which has the advantages of simple structure, convenient assembly and maintenance, good heat dissipation and stable performance.

[0006] The present invention also provides a packaging method for the above-mentioned detachable microchannel semiconductor bar fiber laser module.

[0007] The technical solution of the present invention is as follows:

[0008] A detachable microchannel semiconductor bar fiber laser module includes a housing, a cover plate, a stacked array, a VBG grating, a slow-axis collimating lens, a mirror, a polarization beam combiner, a protective lens, a coupling module, and an optical fiber.

[0009] The housing is a hollow cuboid structure with a cover plate on the upper side. A lens fixing step is provided on one side of the housing. Array fixing steps are symmetrically arranged on both sides of the lens fixing step. Array is set on the array fixing steps. VBG grating and slow-axis collimating lens are arranged sequentially on the lens fixing step on the light-emitting side of the array. A reflector is set at the center of the array fixing step. A polarization beam combiner corresponding to the reflector is provided on the other side of the housing. A protective lens and a coupling module are arranged sequentially on the other side of the polarization beam combiner. An optical fiber is connected to the coupling module.

[0010] Preferably, the array includes a negative electrode block, a microchannel laser, a positive electrode block, a mounting base, and a fast-axis collimating lens. The positive electrode block is mounted on the mounting base via an insulating sheet. The microchannel laser is mounted on the upper side of the positive electrode block. The negative electrode block is mounted on the upper side of the microchannel laser. The fast-axis collimating lens is mounted on the light-emitting side of the microchannel laser.

[0011] In a further preferred embodiment, the positive electrode block and the mounting base are provided with through holes corresponding to the liquid outlet and liquid inlet of the microchannel laser, the housing connected to the stacked array fixing steps is provided with a liquid inlet and a liquid outlet, the liquid inlet and the liquid outlet are connected to the mounting base, and a liquid channel is provided inside the lens fixing steps to facilitate cooling of the lens fixing steps and the stacked array fixing steps.

[0012] Preferably, negative electrode blocks are provided with negative electrode protrusions on both sides, and positive electrode blocks are provided with positive electrode protrusions on both sides. Two adjacent stacked arrays are connected by connecting pieces to form a parallel circuit. The positive electrode protrusions and negative electrode protrusions of the inner stacked arrays are connected to the positive and negative electrodes.

[0013] Preferably, one end of the negative electrode block is provided with a protective notch. The protective notch is used to protect the laser cavity surface and prevent the front end of the negative electrode block from touching the laser bar cavity surface during assembly, which would cause damage to the laser.

[0014] Preferably, the fast-axis collimating lens is made of high-temperature resistant glass with good light transmittance, with a fast-axis collimation residual divergence angle ≤4.5mrad and a transmittance ≥99.8@780-1080nm.

[0015] Preferably, the slow-axis collimating lens is an arc-shaped lens with a slow-axis collimation residual divergence angle ≤10mrad and a transmittance ≥99.8%@780-1080nm.

[0016] Preferably, the reflector has a triangular structure with a reflectivity ≥99.5%@770-1080nm, the protective lens has a forward transmittance ≥99.6%@780-1080nm, and a reverse transmittance ≤0.01%@780-1080nm.

[0017] Preferably, the coupling module is provided with a focusing lens, and an optical fiber is provided on one side of the focusing lens. The optical fiber is fixed to the outside of the housing by a fixing block.

[0018] The packaging method for the above-mentioned detachable microchannel semiconductor bar fiber laser module comprises the following steps:

[0019] (1) First, perform array assembly, take out the mounting base, place the insulating sheet on the mounting base, and pass the fixing screw through the positive electrode block, microchannel laser, negative electrode block, insulating sheet and mounting base. Tighten the fixing screw to form the array.

[0020] (2) Install the fast-axis collimating lens. Install the fast-axis lens on the front end of the microchannel laser and focus the laser in the fast-axis direction. After focusing, cure the fast-axis collimating lens with glue.

[0021] (3) Install the stacked array, fix the stacked array after assembling the fast axis collimating lens onto the stacked array fixing step, and connect the negative pole protrusion and positive pole protrusion of the adjacent stacked arrays together through the connecting piece to form a parallel circuit of the stacked arrays.

[0022] (4) Electrode installation: Put an insulating sleeve between the positive and negative electrodes, pass it through the shell, and fix the positive electrode and the negative electrode together.

[0023] (5) Lens installation: Install the VBG grating, slow-axis collimating lens and mirror onto the lens fixing step, and perform focusing and wavelength locking.

[0024] (6) Install the polarization beam combiner, protective lens and coupling module into the housing in sequence, and refocus. Then fix the optical fiber with the mounting block.

[0025] (7) Piping installation: Install the inlet pipe and outlet pipe to the inlet and outlet on the outside of the housing respectively, connect the lens fixing step and the inside of the stacked array fixing step, and seal them.

[0026] (8) Covering: Place the assembled module into a glove box filled with inert gas, assemble the cover plate onto the upper part of the shell, seal the shell, and complete the packaging of the microchannel semiconductor bar fiber laser.

[0027] The beneficial effects of this invention are as follows:

[0028] 1. The detachable microchannel semiconductor bar fiber laser module of the present invention adopts a detachable laser fixing structure, which replaces the direct sintering of the laser chip onto the shell. The packaging is simpler and easier to operate. The production efficiency is increased by more than 10% compared with the traditional packaging method. At the same time, this structure facilitates the replacement of the laser, avoids the waste of raw materials caused by laser failure, and reduces production costs.

[0029] 2. The fiber laser module of this invention uses a low-temperature microchannel coolant to directly cool the laser, which can quickly and effectively remove the heat generated by the laser, keeping the laser at a constant temperature and greatly improving the performance stability of the laser. At the same time, it effectively avoids product failure caused by poor heat dissipation. The production qualification rate of the fiber laser module with this structure is more than 10% higher than that of the traditional fiber laser structure.

[0030] 3. The laser used in the fiber laser module of the present invention adopts a high-power bar microchannel packaging structure, coupled with good heat dissipation performance, which can increase the power of a single fiber laser to thousands of watts.

[0031] 4. The fiber laser module of the present invention is equipped with a lens cooling function, which can quickly dissipate the heat of the lens, avoid wavelength shift caused by excessive temperature change of the lens, and improve the wavelength stability of the laser by 20%. Attached Figure Description

[0032] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0033] Figure 2 This is a schematic diagram of the internal three-dimensional structure of the present invention.

[0034] Figure 3 This is a top view of the internal structure of the present invention.

[0035] Figure 4 This is a schematic diagram of the three-dimensional structure of the shell of the present invention. Figure I .

[0036] Figure 5 This is a schematic diagram of the three-dimensional structure of the shell of the present invention. Figure II .

[0037] Figure 6 This is a schematic diagram of the stacked array three-dimensional structure of the present invention.

[0038] Figure 7 This is a schematic diagram of the three-dimensional structure of the negative electrode block of the present invention.

[0039] Figure 8 This is a schematic diagram of the three-dimensional structure of the microchannel laser of the present invention.

[0040] Figure 9 This is a schematic diagram of the three-dimensional structure of the positive electrode block of the present invention.

[0041] Figure 10 This is a schematic diagram of the three-dimensional structure of the insulating sheet of the present invention.

[0042] Figure 11 This is a three-dimensional structural diagram of the fixing base of the present invention.

[0043] Figure 12 This is a three-dimensional structural diagram of the coupling module of the present invention.

[0044] Figure 13 This is a three-dimensional structural diagram of the connecting piece of the present invention.

[0045] The components are as follows: 1. Housing; 2. Cover plate; 3. Stacked array; 4. VBG grating; 5. Slow-axis collimating lens; 6. Reflector; 7. Polarizing beam combiner; 8. Protective lens; 9. Coupling module; 10. Fixing block; 11. Optical fiber; 12. Connecting piece; 13. Negative electrode; 14. Positive electrode; 15. Outlet pipe I; 16. Inlet pipe I; 17. Outlet pipe II; 18. Inlet pipe II; 19. Outlet; 20. Inlet; 21. Focusing lens; 22. Fixing screw hole I; 23. Electrode hole; 24. Lens fixing. 25. Fixed step, stacked fixed step, 26. Liquid outlet I, 27. Liquid inlet I, 28. Fixing screw hole II, 29. Fiber optic hole, 30. Negative electrode block, 31. Microchannel laser, 32. Fast axis collimating lens, 33. Positive electrode block, 34. Insulating sheet, 35. Fixing base, 36. Fixing hole I, 37. Protective notch, 38. Negative electrode protrusion, 39. Liquid outlet, 40. Liquid inlet, 41. Fixing hole, 42. Positive electrode protrusion, 43. Positioning groove, 44. Positioning hole, 45. Electrode fixing screw hole. Detailed Implementation

[0046] The present invention will be further described below with reference to the embodiments and accompanying drawings, but is not limited thereto.

[0047] Example 1:

[0048] like Figures 1-13 As shown, this embodiment provides a detachable microchannel semiconductor bar fiber laser module, including a housing 1, a cover plate 2, a stacked array 3, a VBG grating 4, a slow-axis collimating lens 5, a reflector 6, a polarization beam combiner 7, a protective lens 8, a coupling module 9, and an optical fiber 11.

[0049] The housing 1 is a hollow cuboid structure made of copper, a material with good thermal conductivity. A cover plate 2 is located on the upper side of the housing 1. Screw holes Ⅰ22 are located at the four corners of the upper end of the housing for fixing the cover plate 2. A lens fixing step 24 is located on one side of the housing 1. Stacked array fixing steps 25 are symmetrically arranged on both sides of the lens fixing step 24. A stacked array 3 is installed on the stacked array fixing steps 25. A VBG grating 4 and a slow-axis collimating lens 5 are sequentially installed on the lens fixing step 24 on the light-emitting side of the stacked array 3. The VBG grating is used to lock the laser wavelength, stabilizing the laser generated by the microchannel laser within a fixed wavelength range. Inside the enclosure, a reflector 6 is set at the center of the stacked array fixed step 25. The reflector reflects the laser emitted by the microchannel lasers on both sides of the stacked array onto the polarization beam combiner. On the other side of the housing 1, a polarization beam combiner 7 corresponding to the reflector 6 is set. The polarization beam combiner is used to combine the lasers generated by all microchannel lasers into a single laser beam. On the other side of the deflection beam combiner 7, a protective lens 8 and a coupling module 9 are set in sequence. The protective lens is used to prevent the laser emitted by the coupling module from hitting the microchannel laser, so as to avoid damage to the laser. The protective lens has unidirectional projection. An optical fiber 11 is connected to the coupling module 9. The housing is provided with an optical fiber hole 29 for the optical fiber to pass through.

[0050] The array 3 includes a negative electrode block 30, a microchannel laser 31, a positive electrode block 33, a mounting base 35, and a fast-axis collimating lens 32. The positive electrode block 33 is mounted on the mounting base 35 via an insulating sheet 34. A positioning groove 43 is provided in the middle of the mounting base 35 to position the insulating sheet 34, which insulates the positive electrode block from the mounting base. The microchannel laser 31 is mounted on top of the positive electrode block 33, and the negative electrode block 30 is mounted on top of the microchannel laser 31. The fast-axis collimating lens 32 is mounted on the light-emitting side of the microchannel laser 31, with its width and length dimensions adapted to the size of the microchannel laser. The negative electrode block 30, microchannel laser 31, positive electrode block 33, insulating sheet 34, and mounting base 35 are assembled together with fixing screws to form the array. The microchannel laser has a fixing hole 41, and the negative electrode block has a fixing hole 36. The microchannel laser in the array can be replaced by removing and installing the array fixing screws. The four corners of the mounting base 35 are provided with positioning holes 44, which are used to fix the stacked array to the housing.

[0051] The positive electrode block 33 and the mounting base 35 are provided with through holes corresponding to the liquid outlet 39 and liquid inlet 40 of the microchannel laser 31. The housing connected to the stacked array fixing step is provided with a liquid inlet 20 and a liquid outlet 19. The liquid inlet 20 and the liquid outlet 19 are respectively connected to the liquid inlet pipe I 16 and the liquid outlet pipe I 15. The liquid inlet 20 and the liquid outlet 19 are connected to the stacked array fixing step and the mounting base. The stacked array fixing step is provided with a liquid outlet I 26 and a liquid inlet I 27. A liquid channel is provided inside the lens fixing step 24. The liquid channel is connected to the liquid outlet pipe II 17 and the liquid inlet pipe II 18. The lens fixing step is used to fix the VBG grating, the slow axis collimating lens and the reflector, and to dissipate heat for them. The liquid channel inside the lens fixing step is used for heat dissipation. The coolant enters the lens fixing step through the liquid inlet pipe II and then flows out through the liquid outlet pipe II, so that the lens fixing step is kept at a constant low temperature. The height difference between each adjacent lens fixing step is the same and the height difference is greater than the thickness of the microchannel laser. The stacking array fixing steps are used to fix the stacking array and cool it down. The size of the stacking array fixing steps is adapted to the size of the stacking array fixing base. The refrigerant enters the stacking array through the corresponding liquid inlet, through the liquid inlet hole I, and then through the liquid outlet hole I, and finally flows out through the liquid outlet, carrying away the heat generated by the stacking array and keeping the stacking array in a constant low temperature state. The four corners of the stacking array fixing steps are respectively provided with fixing screw holes II28, which are used to fix the stacking array.

[0052] Negative electrode block 30 has negative electrode protrusions 38 on both sides, and positive electrode block 33 has positive electrode protrusions 42 on both sides. Two adjacent stacked arrays 3 are connected by a connecting piece 12 to form a parallel circuit of positive electrode protrusions 42 and negative electrode protrusions 38. The connecting piece 12 is made of a highly conductive metal and has electrode fixing screw holes 45 at both ends. The positive and negative electrode protrusions of the inner stacked array are connected to positive electrode 14 and negative electrode 13. The front and rear sides of the housing 1 each have two electrode holes 23. The inner side of the electrode holes 23 is equipped with an insulating sleeve to prevent the electrodes from contacting the housing. The size and structure of the positive electrode protrusion 42 are the same as those of the negative electrode protrusion 38.

[0053] The coupling module 9 is equipped with a focusing lens 21, and an optical fiber 11 is provided on one side of the focusing lens 21. The optical fiber 11 is fixed to the outside of the housing 1 by a fixing block 10.

[0054] The packaging method for the above-mentioned detachable microchannel semiconductor bar fiber laser module comprises the following steps:

[0055] (1) First, perform array assembly, take out the mounting base, place the insulating sheet on the mounting base, and pass the fixing screw through the positive electrode block, microchannel laser, negative electrode block, insulating sheet and mounting base. Tighten the fixing screw to form the array.

[0056] (2) Install the fast-axis collimating lens. Install the fast-axis lens on the front end of the microchannel laser and focus the laser in the fast-axis direction. After focusing, cure the fast-axis collimating lens with glue.

[0057] (3) Install the stacked array, fix the stacked array after assembling the fast axis collimating lens onto the stacked array fixing step, and connect the negative pole protrusion and positive pole protrusion of the adjacent stacked arrays together through the connecting piece to form a parallel circuit of the stacked arrays.

[0058] (4) Electrode installation: Put an insulating sleeve between the positive and negative electrodes, pass it through the shell, and fix the positive electrode and the negative electrode together.

[0059] (5) Lens installation: Install the VBG grating, slow-axis collimating lens and mirror onto the lens fixing step, and perform focusing and wavelength locking.

[0060] (6) Install the polarization beam combiner, protective lens and coupling module into the housing in sequence, and refocus. Then fix the optical fiber with the mounting block.

[0061] (7) Piping installation: Install the inlet pipe and outlet pipe to the inlet and outlet on the outside of the housing respectively, connect the lens fixing step and the inside of the stacked array fixing step, and seal them.

[0062] (8) Covering: Place the assembled module into a glove box filled with inert gas, assemble the cover plate onto the upper part of the shell, seal the shell, and complete the packaging of the microchannel semiconductor bar fiber laser.

[0063] Example 2:

[0064] A detachable microchannel semiconductor bar fiber laser module is provided, with the structure described in Example 1, except that a protective notch 37 is provided at one end of the negative electrode block 30. The protective notch is used to protect the laser cavity surface and prevent the front end of the negative electrode block from touching the laser bar cavity surface during assembly, which would cause damage to the laser.

[0065] Example 3:

[0066] A detachable microchannel semiconductor bar fiber laser module, with the structure described in Example 1, differs in that the fast-axis collimating lens 32 is made of high-temperature resistant glass with good light transmittance, the fast-axis collimation residual divergence angle is ≤4.5mrad, and the transmittance is ≥99.8@780-1080nm.

[0067] The slow-axis collimating lens 5 is an arc-shaped lens with a slow-axis collimation residual divergence angle ≤10mrad and a transmittance ≥99.8%@780-1080nm.

[0068] The reflector 6 has a triangular structure with a reflectivity ≥99.5%@770-1080nm. The protective lens 8 has a forward transmittance ≥99.6%@780-1080nm and a reverse transmittance ≤0.01%@780-1080nm.

Claims

1. A detachable microchannel semiconductor bar fiber laser module, characterized in that, It includes a housing, cover plate, array, VBG grating, slow-axis collimating lens, reflector, polarizing beam combiner, protective lens, coupling module, and optical fiber. The housing is a hollow cuboid structure with a cover plate on the upper side. A lens fixing step is provided on one side of the housing. Stacked array fixing steps are symmetrically arranged on both sides of the lens fixing step. A stacked array is set on the stacked array fixing steps. A VBG grating and a slow-axis collimating lens are arranged sequentially on the lens fixing step on the light-emitting side of the stacked array. A reflector is set at the center of the stacked array fixing step. A polarization beam combiner corresponding to the reflector is set on the other side of the housing. A protective lens and a coupling module are arranged sequentially on the other side of the deflection beam combiner. An optical fiber is connected to the coupling module. The array includes a negative electrode block, a microchannel laser, a positive electrode block, a mounting base, and a fast-axis collimating lens. The positive electrode block is mounted on the mounting base via an insulating sheet. The microchannel laser is mounted on the upper side of the positive electrode block. The negative electrode block is mounted on the upper side of the microchannel laser. The fast-axis collimating lens is mounted on the light-emitting side of the microchannel laser. The positive electrode block and the fixed base are provided with through holes corresponding to the liquid outlet and liquid inlet of the microchannel laser. The housing connected by the stacked fixed steps is provided with a liquid inlet and a liquid outlet. The liquid inlet and liquid outlet are connected to the fixed base. A liquid channel is provided inside the lens fixed step. Negative electrode blocks have negative electrode protrusions on both sides, and positive electrode blocks have positive electrode protrusions on both sides. Two adjacent stacked arrays are connected by connecting pieces to the positive electrode protrusions and negative electrode protrusions. The positive electrode protrusions and negative electrode protrusions of the inner stacked arrays are connected to the positive electrode and negative electrode.

2. The detachable microchannel semiconductor bar fiber laser module as described in claim 1, characterized in that, A protective notch is provided at one end of the negative electrode block.

3. The detachable microchannel semiconductor bar fiber laser module as described in claim 1, characterized in that, The fast-axis collimating lens is made of glass, with a fast-axis collimation residual divergence angle ≤4.5mrad and a transmittance ≥99.8@780-1080nm.

4. The detachable microchannel semiconductor bar fiber laser module as described in claim 1, characterized in that, The slow-axis collimating lens is an arc-shaped lens with a residual divergence angle of ≤10mrad and a transmittance of ≥99.8%@780-1080nm.

5. The detachable microchannel semiconductor bar fiber laser module as described in claim 1, characterized in that, The reflector has a triangular structure with a reflectivity ≥99.5%@770-1080nm. The protective lens has a forward transmittance ≥99.6%@780-1080nm and a reverse transmittance ≤0.01%@780-1080nm.

6. The detachable microchannel semiconductor bar fiber laser module as described in claim 1, characterized in that, The coupling module is equipped with a focusing lens, and an optical fiber is installed on one side of the focusing lens. The optical fiber is fixed to the outside of the housing by a fixing block.

7. A packaging method for a detachable microchannel semiconductor bar fiber laser module as described in claim 1, characterized in that, The steps are as follows: (1) First, perform array assembly, take out the mounting base, place the insulating sheet on the mounting base, and pass the fixing screw through the positive electrode block, microchannel laser, negative electrode block, insulating sheet and mounting base. Tighten the fixing screw to form the array. (2) Install the fast-axis collimating lens. Install the fast-axis lens on the front end of the microchannel laser and focus the laser in the fast-axis direction. After focusing, cure the fast-axis collimating lens with glue. (3) Install the stacked array, fix the stacked array after assembling the fast axis collimating lens onto the stacked array fixing step, and connect the negative pole protrusion and positive pole protrusion of the adjacent stacked arrays together through the connecting piece to form a parallel circuit of the stacked arrays. (4) Electrode installation: Put an insulating sleeve between the positive and negative electrodes, pass it through the shell, and fix the positive electrode and the negative electrode together. (5) Lens installation: Install the VBG grating, slow-axis collimating lens and mirror onto the lens fixing step, and perform focusing and wavelength locking. (6) Install the polarization beam combiner, protective lens and coupling module into the housing in sequence, and refocus. Then fix the optical fiber with the mounting block. (7) Piping installation: Install the inlet pipe and outlet pipe to the inlet and outlet on the outside of the housing respectively, connect the lens fixing step and the inside of the stacked array fixing step, and seal them. (8) Covering: Place the assembled module into a glove box filled with inert gas, assemble the cover plate onto the upper part of the shell, seal the shell, and complete the packaging of the microchannel semiconductor bar fiber laser.

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