Multipath laser system

Abstract

The utility model provides a kind of multi-channel laser system, comprising: multiple laser components, beam combining component, spatial filter and coupling component, wherein, laser component is used to excite laser, beam combining component is used to carry out beam combining to the laser that multiple laser components emit;Spatial filter filters the laser obtained from beam combining component;Coupling component is used to focus the laser obtained from spatial filter to form cross section overlapping spot.In the above multi-channel laser system, since the laser after beam combining passes through spatial filter, eliminates the noise of laser, diffraction pattern or spot distortion and other problems, it is beneficial to avoid the distortion of beam combining laser after multi-channel laser coupling enters into optical fiber, more in line with actual demand.

Description

Technical Field

[0001] This disclosure relates to the field of laser technology, and more particularly to a multi-channel laser system. Background Technology

[0002] The most commonly used laser in urological surgery is the pulsed holmium laser. During the procedure, the energy generated by the laser is transferred to the stone through water vaporization, causing it to break down into powder. Pulsed lasers are typically characterized by their average power; at the same peak power, the average power is proportional to the product of the pulse width and frequency. A longer pulse width, higher frequency, and greater average power result in better stone powdering.

[0003] Due to the thermal lensing effect of laser crystal materials, the output frequency and pulse energy of a single laser are limited. To overcome these limitations, it is necessary to combine several lasers into a multi-laser system. The technical challenge of multi-laser systems lies in how to couple spatially separated and unrelated laser beams into a single optical fiber.

[0004] However, existing designs, due to design or manufacturing limitations, suffer from issues such as noise, diffraction patterns, or beam distortion when the laser beam coupled into the optical fiber. For example, in PCT patent WO2023108835A1, simultaneous beam combining is achieved through a reflection module and a refraction module. However, the reflection module uses a curved mirror, which alters the beam divergence angle while deflecting the optical path, complicating the optical coupling, easily generating noise and beam distortion, and reducing coupling efficiency. Utility Model Content

[0005] In order to overcome at least one of the defects described in the prior art, the purpose of this disclosure is to provide a multi-channel laser system to solve one or more of the problems of noise, diffraction pattern and spot distortion in lasers emitted into optical fibers.

[0006] This disclosure provides a multi-channel laser system, including:

[0007] Multiple laser components are used to excite the laser;

[0008] A beam combiner is used to combine the laser beams emitted by multiple laser components.

[0009] A spatial filter for filtering laser light emitted from the beam combiner assembly; and

[0010] A coupling component is used to focus the laser obtained from the spatial filter to form a beam of light with overlapping cross sections.

[0011] In some embodiments, the spatial filter includes a first lens, an aperture stop, and a second lens.

[0012] In some embodiments, the first lens is used to focus the laser obtained by the beam combining assembly to pass through the aperture, and the laser obtained from the first lens passes through the aperture and then reaches the second lens, which is used to collimate the laser.

[0013] In some embodiments, the beam combining assembly includes a conical reflector and a plurality of first planar reflectors, the number of laser components corresponding to the number of first planar reflectors, the conical reflector forming a plurality of first reflective planes, the number of first reflective planes corresponding to the number of first planar reflectors, and the first reflective planes being parallel to their corresponding first planar reflectors; or

[0014] In some embodiments, the beam combining assembly includes multiple sets of planar mirror groups, the number of laser components corresponding to the number of planar mirror groups, and each planar mirror group includes at least two planar mirrors.

[0015] In some embodiments, the beam-combining assembly includes a plurality of rhomboid prisms, each of which forms a pair of mutually parallel first reflective planes.

[0016] In some embodiments, the rhomboid prisms abut against each other.

[0017] In some embodiments, a plurality of collimation components are included, the collimation components being located between the laser component and the beam combining component, the number of collimation components corresponding to the number of laser components, wherein the collimation component includes a third lens and a fourth lens, the third lens and the fourth lens being used to adjust the spot size of the laser emitted by the laser component.

[0018] In some embodiments, the laser component, the beam combining component, the spatial filter, and the coupling component are fixed to each other.

[0019] In some embodiments, an optical fiber is also included, into which a light spot focused from the coupling component enters.

[0020] In some embodiments, the number of laser components is 4, and each laser component includes a resonant cavity through which laser light is emitted.

[0021] In the above scheme, since the combined laser beam passes through a spatial filter, problems such as laser noise, diffraction pattern or spot distortion are eliminated. This helps to avoid distortion in the combined laser beam after multiple lasers are coupled into the optical fiber, which is more in line with actual needs. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a multi-channel laser system according to one embodiment of the present disclosure.

[0023] Figure 2 This is a schematic diagram of the structure of a multi-channel laser system according to another embodiment of the present disclosure.

[0024] Figure 3a This is a schematic diagram of the bundle-combining assembly in the first embodiment of this disclosure.

[0025] Figure 3b This is a schematic diagram of the bundle-combining assembly in the second embodiment of this disclosure.

[0026] Figure 3c This is a schematic diagram of the bundle-combining assembly in the third embodiment of this disclosure.

[0027] Figure 4 This is a schematic diagram of the structure of a multi-channel laser system according to another embodiment of this disclosure.

[0028] Figure 5a This is a schematic diagram of the bundle-combining assembly in the fourth embodiment of this disclosure.

[0029] Figure 5b This is a schematic diagram of the bundle-combining assembly in the fifth embodiment of this disclosure.

[0030] Figure 5c This is a schematic diagram of the bundle-combining assembly in the sixth embodiment of this disclosure.

[0031] The diagram is labeled as follows: 100, laser component; 110, focusing cavity; 200, beam combining component; 210, conical mirror; 211, first reflecting plane; 220, first planar mirror; 231, second planar mirror; 232, third planar mirror; 240, rhomboid prism; 241, second reflecting plane; 242, third reflecting plane; 300, spatial filter; 310, first lens; 320, aperture; 330, second lens; 400, coupling component; 500, collimation component; 510, third lens; 520, fourth lens; 600, optical fiber. Detailed Implementation

[0032] To better understand and implement this invention, the technical solutions in this invention will be clearly and completely described below with reference to the accompanying drawings.

[0033] In the description of this disclosure, it should be noted that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "far", "near", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure.

[0035] This disclosure provides a multi-channel laser system, such as Figure 1 or Figure 2 As shown, it includes: multiple laser components 100, a beam combiner 200, a spatial filter 300, and a coupling component 400, wherein the laser components 100 are used to excite lasers; the beam combiner 200 is used to combine the lasers emitted by the multiple laser components 100; the spatial filter 300 is used to filter the lasers obtained from the beam combiner 200; and the coupling component 400 is used to focus the lasers obtained from the spatial filter 300 to form a beam with overlapping cross sections.

[0036] Specifically, multiple parallel laser beams emitted from multiple laser components 100 will travel to a beam combiner 200, which will combine these beams to obtain overlapping or nearly overlapping laser beams. A spatial filter 300 is placed between the beam combiner 200 and the coupling component 400 to filter the laser beams received by the beam combiner 200. The coupling component 400 will focus the laser beams received from the spatial filter 300 to form overlapping cross-sections. In terms of the optical path, the laser components 100, beam combiner 200, spatial filter 300, and coupling component 400 are connected sequentially.

[0037] Optionally, the spatial filter 300 includes a first lens 310, an aperture 320, and a second lens 330. The laser obtained from the beam combiner 200 first passes through the first lens 310, where it is focused. The focused laser then passes through the aperture 320 and reaches the second lens 330, where it is "restored." Specifically, the laser passing through the aperture 320 is relatively divergent, making it difficult to refocus into the fiber 600. Therefore, the second lens 330 collimates it into multiple parallel laser beams for subsequent focusing by the coupling assembly 400. In this scheme, the aperture 320 is used to reduce laser noise, diffraction patterns, and spot distortion, ensuring better quality of the laser entering the fiber 600. It should be noted that although theoretically multiple laser beams should be combined into one after passing through the beam combiner 200, sometimes due to process or error reasons, these multiple laser beams may only be close to each other and partially overlap, but not completely overlap. Therefore, after multiple laser beams are focused by the first lens 310 and the aperture 320, they may form multiple dispersed laser beams, thus requiring the second lens 330 for collimation and restoration. Furthermore, a through-hole should be formed in the aperture to allow the laser beam to pass through. In addition, both the first lens 310 and the second lens 330 can be convex lenses. The focal point of the first lens 310 can be located at the through-hole of the aperture 320, and the focal point of the second lens 330 can also be located at the through-hole of the aperture. The first and second lenses can be adjusted as needed so that the distribution and spot size of the combined laser beam leaving the second lens are approximately the same as the distribution and spot size of the combined laser beam entering the first lens. In some embodiments, the first and second lenses can be lenses with the same focal length (the slight difference between the first and second lenses lies in their surface shape, such as whether they are aspherical or spherical), the distance between the first and second lenses is twice the focal length of the first and second lenses, and the through-hole of the aperture should be located at the common focal point of the first and second lenses. In some embodiments, the spatial filter design parameters are as follows: for example, if the laser wavelength is 2100nm and the laser spot is 3mm, then the lens focal length is 20mm and the aperture diameter is about 40μm.

[0038] In some embodiments, the coupling assembly 400 includes a lens for focusing the laser. Specifically, the lens has a specific focal length to focus the laser emitted from the spatial filter into a spot with overlapping cross-sections, thereby guiding it into the optical fiber.

[0039] In some embodiments, such as Figure 2As shown, the beam combiner 200 includes a conical reflector 210 and a plurality of first planar reflectors 220. The number of laser components 100 corresponds to the number of first planar reflectors 220. The conical reflector 210 forms a plurality of first reflecting planes 211, the number of which corresponds to the number of first planar reflectors 220. The first reflecting planes 211 and their corresponding first planar reflectors 220 are parallel to each other. Specifically, the multiple lasers entering the beam combiner 200 firstly contact the plurality of first planar reflectors 220 respectively, and after reflection by the first planar reflectors 220, they converge into the conical reflector 210 and are reflected out by the conical reflector 210. Since the first reflecting planes 211 of the conical reflectors 210 are relatively close to each other, the lasers reflected out by the conical reflectors 210 will overlap or nearly overlap, thus forming a beam combiner of multiple lasers. Secondly, the corresponding first reflecting planes 211 of the first planar reflector 220 and the conical reflector 210 are parallel to each other, ensuring that the multiple laser beams entering the beam combiner 200 are parallel to the combined laser beams leaving the beam combiner 200. The light incident angle of the first planar reflector 220 is 15-75°, and can be selected as 45°. For example... Figure 3a As shown, the light incident angle of the first plane mirror 220 and the first reflecting plane 211 is approximately 15°. Figure 3b As shown, the light incident angle of the first plane mirror 220 and the first reflecting plane 211 is approximately 45°. Figure 3c As shown, the light incident angle of the first planar reflector 220 and the first reflecting plane 211 is approximately 75°. The advantage of this design is that the light incident angle can be adjusted as needed, allowing for adjustments to the positions of the first planar reflector 220 and the conical reflector 210 based on the actual environment. This results in smoother laser propagation throughout the system and facilitates adjustments to the positions of various components based on heat dissipation requirements, achieving better heat dissipation. In some embodiments, the beam combining assembly 200 includes four first planar reflectors 220, and the conical reflector 210 includes four first reflecting planes 211.

[0040] In some embodiments, such as Figure 1As shown, the beam combiner 200 includes multiple sets of planar mirror groups, with the number of laser components 100 corresponding to the number of planar mirror groups. Each planar mirror group includes at least two planar mirrors. Specifically, each planar mirror group includes at least a second planar mirror 231 and a third planar mirror 232. When laser light enters the beam combiner 200, the second planar mirror 231 reflects it to the third planar mirror 232, which then reflects it again. Because the third planar mirrors 232 of each planar mirror group are close to or abut against each other, the laser light reflected by the third planar mirrors 232 in each planar mirror group overlaps or nearly overlaps, thereby achieving beam combining. In some embodiments, the beam combiner 200 includes four sets of planar mirror groups.

[0041] In some embodiments, such as Figure 4 As shown, the beam combiner 200 includes multiple rhombic prisms 240. Specifically, the beam combiner 200 includes at least four rhombic prisms 240, each rhombic prism 240 forming a pair of mutually parallel reflecting planes. The characteristic of the rhombic prisms 240 is that, under normal conditions, the outgoing light from the rhombic prisms 240 is always parallel to the incident light, making the laser beam path insensitive to the deformation of the rhombic prisms 240, thus enhancing the stability of the laser system. The light incident angle of the reflecting planes of the rhombic prisms 240 is 15°-75°, optionally 45°, as shown in the figure. Figures 5a-5c As shown.

[0042] Specifically, the rhombic prism 240 includes a second reflecting plane 241 and a third reflecting plane 242, which are parallel to each other. Laser light entering the beam combiner 200 first strikes the second reflecting plane 241, then is reflected by it to the third reflecting plane 242 of the rhombic prism 240, and finally is reflected out of the rhombic prism 240 by the third reflecting plane 242. Because the third reflecting planes 242 of each rhombic prism 240 are close to and parallel to each other, the laser light reflected from the third reflecting planes 242 of each rhombic prism 240 overlaps or nearly overlaps, thus completing the beam combining of multiple laser beams. It should be noted that the pair of parallel reflecting planes of the rhombic prism 240 can be the second reflecting plane 241 and the third reflecting plane 242.

[0043] The characteristic of a rhombus prism is that when the prism rotates, the direction of the emitted light remains unchanged; that is, the emitted light is always parallel to the direction of the incident light. Generally, mechanical deformation or stress release may cause the rhombus prism to rotate. Because the two reflecting planes of the rhombus prism always remain parallel, the deflection of the light path caused by the rotation of the first reflecting plane is canceled out by the rotation of the second reflecting plane. Therefore, the emitted light after the rhombus prism rotates is also parallel to the direction of the incident light, reducing the impact of deformation on the light path.

[0044] In some embodiments, such as Figure 5a and Figure 5b As shown, multiple rhomboid prisms 240 abut against each other. Furthermore, in some embodiments, the multiple rhomboid prisms 240 may also be separated from each other, such as... Figure 5c As shown. In addition, multiple connectors can be provided between the rhombic prisms 240 for connection. The connectors are made of metal or other structures, or the rhombic prisms 240 can be mounted on a metal base.

[0045] In some embodiments, the multi-path laser system includes multiple collimation components 500, the number of which corresponds to the number of laser components 100. Each collimation component 500 includes a third lens 510 and a fourth lens 520, which are used to adjust the spot size of the laser emitted by the laser component 100. First, by adjusting the axial position (Z) of the third lens 510 and the fourth lens 520, the laser emitted by the laser component 100 can be collimated, ensuring that each laser path remains parallel to each other while maintaining independent collimation, thus facilitating coupling. Second, the third lens 510 and the fourth lens 520 in this disclosure can adjust the spot size of the laser emitted by the laser component 100, so that the spot size of the laser after subsequent beam combining can match the size of the aperture 320 in the spatial filter 300, facilitating subsequent laser trimming by the spatial filter 300. Furthermore, by adjusting the lateral position (X or Y) of the third lens 510 and the fourth lens 520, the laser emitted by the laser assembly 100 can be angularly deflected or positionally translated, providing additional degrees of freedom to correct errors in various optical instruments. It should be noted that the focal lengths of the third lens 510 and the fourth lens 520 can be the same or different, and the surface profiles of the third lens 510 and the fourth lens 520 can be positive curvature, negative curvature, or a combination of both. In some embodiments, in terms of the optical path, the collimating assembly 500 is located between the laser assembly 100 and the beam combiner assembly 200.

[0046] In some embodiments, the laser component 100, beam combiner 200, spatial filter 300, and coupling component 400 are fixed to each other. Furthermore, the collimation component 500, optical fiber 600, laser component 100, beam combiner 200, spatial filter 300, and coupling component 400 are all fixed to each other. All of the above components can be mounted and fixed to a housing or object, thus securing them to each other. It should be noted that the traditional industry practice tends to use a servo motor to drive a reflector to rotate, combining laser beams from different positions in a time-division manner, and finally coupling them into the optical fiber, as described in utility model patent publication number CN204577829U. The aforementioned existing method relies on a servo motor to combine laser beams from different positions in a time-division manner. However, this method can only output light from each optical path in a time-division manner, not simultaneously. Furthermore, the motor-driven movement of the reflector can also introduce mechanical instability. Therefore, this disclosure employs a method in which the laser component 100, the beam combiner 200, the spatial filter 300, and the coupling component 400 are mutually fixed, enabling the lasers emitted by multiple laser components to be emitted simultaneously, ensuring that the emission frequency and pulse energy of the fiber optic output meet the requirements, as well as the stability of the fiber optic output. Furthermore, since the beam combiner 200 is a static optical structure, the emission of any one laser will not affect the emission of other lasers; that is, each laser is independent in both space and time.

[0047] In some embodiments, the multi-channel laser system further includes an optical fiber 600 into which a light spot focused from the coupling component 400 enters.

[0048] In some embodiments, the number of laser components 100 is four, and each laser component 100 includes a resonant cavity through which laser light is emitted. Each resonant cavity is composed of a focusing cavity 110, a total reflection mirror, and a partial reflection mirror. The laser light emitted through the focusing cavity 110 undergoes multiple reflections by the total reflection mirror and the partial reflection mirror to emit laser light of a specific wavelength. Furthermore, there are various alternatives to the laser unit, and it is not limited to the structure described above.

[0049] It should be noted that, since the number of laser components 100 is four, in some embodiments, the beam combiner 200 includes four planar mirrors, and its conical mirror 210 forms four reflecting planes. In other embodiments, the beam combiner 200 includes four rhombic prisms 240.

[0050] In some embodiments, each laser component 100 first emits a laser beam into a collimating component 500 corresponding to that laser component 100. The collimating component 500 shapes the laser beam, for example, by collimating, magnifying, or reducing the beam size. Furthermore, additional degrees of freedom can be provided by adjusting the positions of components (e.g., the third lens 510 and the fourth lens 520) within the collimating component 500 to correct optical path errors. Next, after passing through the collimating component 500, the laser beam reaches the beam combiner 200. After beam combining in the beam combiner 200, the laser beam is transmitted to a spatial filter 300 for adjustment. The laser beam after passing through the spatial filter 300 passes through a coupling component 400 and is focused by the coupling component 400 before being transmitted into the optical fiber 600.

[0051] In the above scheme, since the combined laser beam passes through the spatial filter 300, problems such as laser noise, diffraction pattern, or spot distortion are eliminated, which helps to achieve higher power of the laser propagating in the fiber 600 and better meet actual needs. Moreover, in addition to collimating the laser and making each laser beam more parallel, the collimating component 500 of this disclosure can also adjust the laser spot size to work together with the aperture 320 in the spatial filter 300 to eliminate various problems in the laser beam.

[0052] In addition, the diamond prism 240 reduces the impact of component deformation on laser transmission, ensuring that the final output laser meets the requirements.

[0053] The technical means disclosed herein are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this disclosure, and these improvements and modifications are also considered within the scope of protection of this disclosure.

Claims

1. A multi-channel laser system, characterized in that, include: Multiple laser components are used to excite the laser; A beam combiner is used to combine the laser beams emitted by multiple laser components. A spatial filter is used to filter laser light emitted from the beam combiner assembly; as well as A coupling component is used to focus the laser obtained from the spatial filter to form a beam of light with overlapping cross sections.

2. The multi-channel laser system according to claim 1, characterized in that, The spatial filter includes a first lens, an aperture, and a second lens.

3. The multi-channel laser system according to claim 2, characterized in that, The first lens is used to focus the laser obtained by the beam combining assembly to pass through the aperture. The laser obtained from the first lens passes through the aperture and then reaches the second lens, which is used to collimate the laser.

4. The multi-channel laser system according to claim 1, characterized in that, The beam combining assembly includes a conical reflector and a plurality of first planar reflectors. The number of laser components corresponds to the number of first planar reflectors. Each conical reflector forms a plurality of first reflective planes, the number of which corresponds to the number of first planar reflectors. The first reflective planes are parallel to their corresponding first planar reflectors. The beam combining assembly includes multiple sets of planar mirror groups, and the number of laser components corresponds to the number of planar mirror groups. Each planar mirror group includes at least two planar mirrors.

5. The multi-channel laser system according to claim 1, characterized in that, The beam combining assembly includes a plurality of rhomboid prisms, each of which forms a pair of mutually parallel first reflective planes.

6. The multi-channel laser system according to claim 5, characterized in that, The rhomboid prisms described herein abut against each other.

7. The multi-channel laser system according to claim 1, characterized in that, It includes multiple collimation components located between the laser component and the beam combining component. The number of collimation components corresponds to the number of laser components. Each collimation component includes a third lens and a fourth lens, which are used to adjust the spot size of the laser emitted by the laser component.

8. The multi-channel laser system according to claim 1, characterized in that, The laser component, the beam combining component, the spatial filter, and the coupling component are fixed to each other.

9. The multi-channel laser system according to any one of claims 1-8, characterized in that, It also includes an optical fiber, into which the light spot focused from the coupling component enters.

10. The multi-channel laser system according to any one of claims 1-8, characterized in that, The number of laser components is 4, and each laser component includes a resonant cavity through which laser light is emitted.

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