Axial lens water-jet guided laser automatic coupling system

Abstract

The utility model belongs to the technical field of water-jet guided laser, and relates to a shaft lens water-jet guided laser automatic coupling system, which comprises a laser, a beam expander, a wave plate, a detection light source, a focusing module, a light focusing plate, a control system and a sample piece, the emitted light of the laser is expanded and shaped into parallel light, then the parallel light is converted into a circularly polarized light beam state, the parallel light is turned to enter the gradient refraction lens, and the gradient variable refractive index distribution is gradually reduced along the radial direction, so that the light transmitted along the axial direction can be continuously refracted, and the emergent light can be smoothly and continuously converged to one point; by adopting the gradient refraction module and the adjustable reflecting mirror, the laser beam can be more effectively coupled into the beam column, the energy loss is reduced, and the laser water jet coupling efficiency of water-jet guided laser processing is effectively improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of water-guided lasers and relates to an axis-lens water-guided laser automatic coupling system. Background Art

[0002] Water-guided laser technology is an advanced laser processing technology. Its principle is to use the phenomenon of total reflection of laser at the interface between water and air to couple the laser beam into a fine water jet, and maintain a very high laser energy density in the water jet, thereby realizing the processing of materials. However, the existing water-guided laser coupling device still faces some challenges in practical applications. For example, when light encounters different media during propagation, its propagation direction will change due to the different refractive indices of the media. In the existing water-guided laser processing, the lens controls the curvature of the lens surface and uses the optical path difference generated by the lens to make the light converge into a point ( Figure 1 ).

[0003] Therefore, existing coupling devices often have the following problems: the light spot in the actual optical path system is difficult to focus; the laser focused beam is difficult to adjust concentricity with the center of the nozzle; the minimum point of the laser beam after focusing is difficult to ensure at the center of the upper surface of the nozzle, etc., resulting in limited coupling efficiency: due to optical design or structural limitations, the laser beam loses a lot of energy during the coupling process, reducing the overall processing efficiency. Poor stability: Affected by environmental factors or mechanical vibrations, the coupling effect of the light beam is prone to fluctuations, affecting the processing quality. Poor adjustability: It is unable to flexibly adapt to different laser parameters or processing requirements, limiting the applicability of the device.

[0004] In order to meet the growing demand for high-precision and high-efficiency processing, a new type of laser coupling device is urgently needed to solve the above problems. Utility Model Content

[0005] In order to solve the above technical problems, the utility model is specifically implemented through the following technical solutions.

[0006] An axis lens water-guided laser automatic coupling system, including: a laser, a beam expander, a wave plate, a detection light source, a focusing module, a light-aiming plate, a control system, and a sample;

[0007] The emitted laser of the laser faces the incident direction of the beam expander, the laser beam expanded by the beam expander faces the incident direction of the wave plate, and the output light of the wave plate is directed to the first beam splitter; the emitted laser of the laser passes through the beam expander and the wave plate in sequence, and the polarized beam is converted into a circularly polarized beam and is directed into the first beam splitter;

[0008] The outgoing laser of the first beam splitter is directly facing the incident direction of the focusing module. The outgoing light of the focusing module passes through the optical alignment plate and then irradiates on the laser incident port of the water jet coupling cavity. The water jet coupling cavity is connected to a water supply system, and the laser water jet coupled by the water jet coupling cavity irradiates on the processing surface of the sample for laser processing.

[0009] Preferably, the coupling system further includes: a detection light source, a control system, and a CCD camera. The emitted light of the detection light source is directed towards the second beam splitter. The outgoing detection light of the second beam splitter is directly facing the incident direction of the focusing module, and the imaging lens of the CCD camera is facing the direction of the outgoing detection light of the second beam splitter; The optical path of the outgoing detection light of the second beam splitter coincides with the optical path of the outgoing laser of the first beam splitter;

[0010] A fine movement module is provided on the focusing module, and the fine movement module drives the focusing module to move slightly up and down along the incident direction of the laser;

[0011] The detection light source, the CCD camera, the laser, the water supply system, and the fine movement module are respectively electrically connected to the control system.

[0012] Preferably, the included angle between the outgoing light of the wave plate and the mirror surface of the first beam splitter is 45°, and the included angle between the emitted light of the detection light source and the mirror surface of the second beam splitter is 45°.

[0013] Preferably, the beam expander is, in sequence along the incident direction of the laser, a concave lens and a convex lens.

[0014] Preferably, the wave plate is a quarter-wave plate.

[0015] Preferably, the focusing module is a gradient refractive lens; the gradient refractive index distribution gradually decreases along the radial direction, which can cause the light transmitted along the axial direction to undergo continuous refraction, so as to realize the smooth and continuous convergence of the outgoing light rays to a point, and achieve more efficient, stable and flexible laser beam coupling.

[0016] The usage method of the coupling system of the present utility model includes the following steps:

[0017] Step S1: The laser emits a beam, which is shaped into a parallel beam by the beam expansion system, and after passing through the quarter-wave plate, the linearly polarized beam emitted by the laser is converted into a circularly polarized beam state, providing uniform and high-quality light spots in various states during later laser processing;

[0018] Step S2: Then, the beam is deflected under the first beam splitter and enters the gradient refractive lens;

[0019] Step S3: The gradient refractive lens focuses the light beam into a non-diffracting light beam that is smaller than the nozzle diameter of the water jet coupling cavity, has a long collimation range, and a small central light spot, and then undergoes total internal reflection propagation inside the water column; the generated slender laser water jet moves relative to the workpiece to process the workpiece.

[0020] Step S4: The light beam emitted by the detection light source passes through the second beam splitter and the first beam splitter, passes through the gradient refractive lens, and directly irradiates the upper surface of the nozzle of the water jet coupling cavity. According to the reversibility of the light path, the CCD camera takes a picture of the center position of the nozzle, and the control system calculates the center position coordinates (x1, y1).

[0021] Step S6: The control system starts the micro-movement module to move the focusing module to a place far from the nozzle center, and at the same time controls the laser to emit laser light to process the marking point on the light alignment plate.

[0022] Step S9: Under the power meter, the control system controls the height of the micro-movement module to adjust the focal position focused by the focusing module to maximize the water-light coupling rate, so that the laser power is more fully applied in the processing.

[0023] Step S7: By detecting and calculating the center position of the nozzle and the position of the laser beam in the coupling cavity, the deviation values (δx, δy) of the laser beam relative to the nozzle center position are obtained.

[0024] Step S8: The control system starts the micro-movement module to move the focusing module by (δx, δy) on the basis of the plane (x2, y2) so that the center of the focused light beam overlaps with the nozzle center position, and the position calibration is completed.

[0025] Step S9: Under the power meter, the control system controls the height of the micro-movement module to adjust the focal position focused by the focusing module to maximize the water-light coupling rate, so that the laser power is more fully applied in the processing.

[0026] Step S10: The control system controls the laser and the water supply system to process the corresponding parts according to the drawing.

[0027] The beneficial effects of the present utility model are as follows:

[0028] 1. The present utility model has a higher coupling efficiency: By adopting a gradient refractive module and an adjustable mirror, the present utility model can more effectively couple the laser beam into the beam column, reduce energy loss, and effectively improve the laser water jet coupling efficiency of water-guided laser processing.

[0029] 2. The present utility model has higher stability: By combining a detection system and a micro-movement module, the present utility model makes the coupling of the light beam more stable, is not interfered by external factors, and improves the laser water jet processing stability of water-guided laser processing.

[0030] 3. The utility model has higher precision: the utility model improves the accuracy of coupling, thereby realizing laser processing with higher precision and enhancing the processing precision of water-guided laser processing.

[0031] 4. The utility model is easier to operate and control: the overall structure design is more reasonable, and the operation and control are simpler and more convenient, making the operation and control of the operator during water-guided laser processing simpler, more convenient, and with strong controllability.

[0032] 5. The utility model has lower costs: the utility model reduces the adjustment difficulty of the laser water jet coupling device, improves the coupling efficiency, and enhances the processing efficiency and qualification rate. Therefore, the utility model reduces the equipment cost, maintenance cost, and production cost to a certain extent. Description of the Drawings

[0033] Figure 1 It is a schematic diagram of the optical path difference convergence on the surface of the water-guided laser lens of the prior art;

[0034] Figure 2 It is a schematic diagram of the optical path difference convergence of the gradient refractive lens of the automatic coupling system of the axial lens water-guided laser of the present utility model;

[0035] Figure 3 It is a schematic diagram of the automatic coupling system of the water-guided laser of the present utility model.

[0036] In the figure, 1. Laser; 2. Beam expander; 3. Wave plate; 4. Detection light source; 5. CCD camera; 6. Focusing module; 7. Optical alignment plate; 8. Micro-movement module; 9. Control system; 10. Specimen; 11. First beam splitter; 12. Water jet coupling cavity; 13. Water supply system; 14. Second beam splitter. Detailed Embodiment

[0037] Next, the related technologies in the present utility model will be clearly and completely described in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.

[0038] The self-focusing lens water-guided laser coupling system of this embodiment. The difference between the self-focusing lens and the ordinary lens is that the self-focusing lens utilizes the change characteristic that the gradient refractive index distribution gradually decreases along the radial direction, which can make the light transmitted along the axial direction generate continuous refraction, thereby realizing the smooth and continuous convergence of the outgoing light to a point, as Figure 2As shown. By introducing innovative components such as a gradient refraction module, a detection system, a fine movement module, and an optical plate, it aims to overcome the limitations of the prior art and achieve more efficient, stable, and flexible laser beam coupling.

[0039] This embodiment can bring the following potential benefits to the laser processing field: improving production efficiency, reducing costs, enhancing processing quality, meeting higher precision requirements, and enhancing the applicability of the device to adapt to diverse processing scenarios.

[0040] The water-guided laser automatic coupling system consists of a laser 1, a beam shaping system (including: a beam expander 2, a wave plate 3), a detection system (including: a detection light source 4, a CCD camera 5), a focusing module 6, an optical plate 7, a fine movement module 8, a control system 9, a sample 10, etc. The system is as Figure 3 shown:

[0041] The following further details this embodiment in conjunction with the system schematic diagram.

[0042] First, the beam emitted by the laser 1 is shaped into a parallel beam by the beam shaping system, and after passing through the quarter-wave plate 3, the linearly polarized light of the beam emitted by the laser 1 is converted into a circularly polarized beam state, providing a uniform and high-quality light spot in various states for subsequent laser processing. Then, the beam is deflected by a 45° first beam splitter 11 and enters a gradient refraction lens (focusing module 6, where the focusing module 6 can also be composed of multiple gradient refraction lenses to form the center of the gradient refraction lens). The gradient refraction lens focuses the beam into a non-diffracting beam with a diameter smaller than the nozzle diameter of the water jet coupling cavity 12, a long collimation range, and a small central light spot, and then undergoes total internal reflection propagation inside the water column. The resulting slender water column beam and the workpiece perform relative movement to process the part.

[0043] Secondly, during the assembly and manufacturing of the water jet coupling cavity 12 and the nozzle, the center of the nozzle and the center of the laser beam are not concentric. This results in a positional deviation, causing the laser beam and the water column in the water jet coupling cavity 12 to not undergo total internal reflection for beam propagation, which will damage or ablate the nozzle in the water jet coupling cavity 12. In such cases, a new nozzle device needs to be replaced, and the beam center and the nozzle need to be recalibrated. Therefore, based on the above situation, a position detection system is used for calibration and adjustment. It includes a detection light source 4 and a CCD camera 5. The beam emitted by the detection light source 4 passes through a 45° second beam splitter 14 and a 45° first beam splitter 11, passes through the gradient refraction lens, and directly irradiates the upper surface of the nozzle of the water jet coupling cavity 12. According to the reversibility of the optical path, the CCD camera 5 takes a photo of the nozzle center position to calculate the center position coordinates (x1, y1).

[0044] Thirdly, the control system activates the fine movement module 8 to move the focusing module 6 to a position farther away from the nozzle center, and at the same time controls the laser 1 to emit light to process a marking point on the light alignment plate.

[0045] Fourthly, the control system 9 activates the CCD camera 5 in the detection system to take a picture of the marking point to obtain the coordinates, and at the same time calculates the position coordinates (x2, y2) of the marking point.

[0046] Fifthly, through the detection and calculation of the nozzle center position and the position of the laser beam in the water jet coupling cavity 12, the deviation values (δx, δy) of the laser beam relative to the nozzle center position are obtained.

[0047] Sixthly, the control system 9 activates the fine movement module 8 to move the focusing module 6 by (δx, δy) on the basis of the plane (x2, y2), so that the center of the focused beam overlaps with the nozzle center position, and the position calibration is completed.

[0048] Seventhly, under the power meter, the control system 9 controls the height of the fine movement module 8 to adjust the focal position focused by the focusing module 6, so that the water-light coupling rate reaches the maximum, and the laser power is more fully applied in processing.

[0049] Eighthly, the control system 9 controls the laser 1, the water supply system 13, etc. to process corresponding parts according to the drawing.

[0050] In summary, the present utility model replaces the existing lens with a gradient refractive lens, utilizes the change characteristic that the gradient refractive index distribution gradually decreases along the radial direction, enables the light transmitted along the axial direction to generate continuous refraction, and thus realizes the smooth and continuous convergence of the outgoing light to a point; by adopting a gradient refraction module and an adjustable mirror, the laser beam can be more effectively coupled into the beam column, reducing energy loss; therefore, the present utility model has a higher coupling efficiency.

[0051] It should be emphasized that the above are only the preferred embodiments of the present utility model, and do not impose any form of limitation on the present utility model. Any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present utility model still fall within the scope of the technical solution of the present utility model.

Claims

1. An axis lens water-guided laser automatic coupling system, characterized in that: include: Laser (1), beam expander (2), wave plate (3), detection light source (4), focusing module (6), light alignment plate (7), sample (10); The emitted laser light of the laser (1) faces the incident direction of the beam expander (2), the laser light expanded by the beam expander (2) faces the incident direction of the wave plate (3), and the output light of the wave plate (3) is emitted toward the first beam splitter (11); the emitted laser light of the laser (1) passes through the beam expander (2) and the wave plate (3) in sequence, and the polarized light beam is converted into a circularly polarized light beam and emitted into the first beam splitter (11); The outgoing laser of the first beam splitter (11) faces the incident direction of the focusing module (6), and the outgoing light of the focusing module (6) passes through the light-aiming plate (7) and is irradiated on the laser incident port of the water jet coupling cavity (12). The water jet coupling cavity (12) is connected to a water supply system (13), and the laser water jet coupled by the water jet coupling cavity (12) is irradiated on the processing surface of the sample (10) to perform laser processing.

2. The axis-lens water-guided laser automatic coupling system according to claim 1, characterized in that: The coupling system further comprises: a detection light source (4), a control system (9), and a CCD camera (5); the emission light of the detection light source (4) is directed toward a second beam splitter (14); the outgoing detection light of the second beam splitter (14) faces the incident direction of the focusing module (6); the camera lens of the CCD camera (5) faces the direction of the outgoing detection light of the second beam splitter (14); and the optical path of the outgoing detection light of the second beam splitter (14) coincides with the optical path of the outgoing laser of the first beam splitter (11); The focusing module (6) is provided with a micro-motion module (8), and the micro-motion module (8) drives the focusing module (6) to micro-move up and down along the incident direction of the laser; The detection light source (4), CCD camera (5), laser (1), water supply system (13), and micro-motion module (8) are electrically connected to the control system (9) respectively.

3. The axis-lens water-guided laser automatic coupling system according to claim 1, characterized in that: The included angle between the emitted light of the wave plate (3) and the mirror surface of the first beam splitter (11) is 45°, and the included angle between the emitted light of the detection light source (4) and the mirror surface of the second beam splitter (14) is 45°.

4. The axis-lens water-guided laser automatic coupling system according to claim 1, characterized in that: The beam expander (2) is a concave lens and a convex lens in sequence along the incident direction of the laser.

5. The axis-lens water-guided laser automatic coupling system according to claim 1, characterized in that: The wave plate (3) is a quarter wave plate.

6. The axis-lens water-guided laser automatic coupling system according to claim 1, characterized in that: The focusing module (6) is a gradient refractive lens.

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