Fiber beam combining device and laser

Abstract

The utility model provides a fiber beam combining device and a laser, and relates to the technical field of laser equipment. The fiber beam combining device includes a first fiber laser, a second fiber laser, a first laser beam combiner, and a second laser beam combiner. A plurality of first fiber lasers are used to generate Gaussian laser beams, a plurality of second fiber lasers are used to generate ring laser beams, the first laser beam combiner can fuse a plurality of first sub-fibers to the first fiber, the second laser beam combiner can combine to form a combined laser, the first fiber and a plurality of second fibers are respectively coupled to transition fibers, and the diameter gradually increases from the transition fiber to the output fiber. The first laser beam combiner of the utility model is used to fuse a plurality of first sub-fibers to the first fiber, and then couple the first fiber and the second fiber, and adopt a step-by-step fusion coupling method to form a combined laser and output it, so as to reduce signal loss, reduce heat accumulation caused by combining, and reduce the cladding light existing in the output fiber.

Description

Technical Field

[0001] The utility model relates to the technical field of laser equipment, in particular to an optical fiber beam combining device and a laser. Background Art

[0002] Fiber combiners are fiber devices used to melt and taper fiber bundles. They can strip the coating off the optical fibers, arrange them together in a certain way, heat them at high temperatures to melt them, and stretch the fiber bundles in opposite directions. Currently, combined lasers are used in laser welding. Combined lasers include central lasers and ring lasers. The high-power density central laser is mainly used to produce keyholes and affect the melting depth. The low-power density external ring laser affects the keyhole size and the molten pool. The combination of the two types of lasers can easily lead to high temperatures in the combined cone area and fiber breakage. Utility Model Content

[0003] The purpose of the utility model is to provide an optical fiber beam combining device and a laser, which adopt a step-by-step fusion coupling method to reduce signal loss, reduce heat accumulation caused by beam combining, avoid excessive corrosion of the optical fiber, reduce the occurrence of output optical fiber breakage, and improve the toughness of the output optical fiber.

[0004] A first aspect of the utility model provides a fiber beam combining device, which includes a first fiber laser, a second fiber laser, a first laser beam combiner, and a second laser beam combiner.

[0005] A plurality of first fiber lasers, for generating Gaussian laser beams, wherein the first fiber lasers include first sub-fibers;

[0006] a plurality of second fiber lasers for generating annular laser beams, wherein the second fiber lasers include second optical fibers;

[0007] a first laser beam combiner capable of fusing a plurality of the first sub-optical fibers to a first optical fiber;

[0008] The second laser beam combiner is capable of combining the annular laser beam and the Gaussian laser beam into a combined laser beam. The second laser beam combiner includes a transition fiber and an output fiber. The first fiber and a plurality of the second fibers are respectively coupled to the transition fiber, and the diameter of the transition fiber gradually increases to the diameter of the output fiber.

[0009] In a possible embodiment of the present invention, a plurality of the second fiber lasers are disposed around the first laser beam combiner.

[0010] In a possible embodiment of the present invention, the optical fiber beam combining device further includes a plurality of film strippers, and one of the film strippers corresponds to one of the second optical fiber lasers.

[0011] In a possible embodiment of the present invention, the transition optical fiber and the output optical fiber both include a core and a cladding, the cladding is wrapped around the core, the core corresponds to the first optical fiber, and the cladding corresponds to a plurality of the second optical fibers respectively.

[0012] In a possible embodiment of the present invention, the transition optical fiber and the output optical fiber further include a coating layer, and the coating layer is wrapped around a side of the cladding away from the core.

[0013] In a possible embodiment of the present invention, the diameter of the first optical fiber is D1, and the diameter of the fiber core is D2, satisfying 0.7D2≤D1≤D2.

[0014] In a possible embodiment of the present invention, the diameter of the second optical fiber is D3, the thickness of the cladding is D4, and 0.8D4≤D3≤D4 is satisfied.

[0015] In a possible embodiment of the present invention, the transition optical fiber includes a coupling section and a pump section, the coupling section is connected to the output optical fiber through the pump section, and the diameter gradually increases from the coupling section to the pump section.

[0016] In a possible embodiment of the present invention, the output optical fiber is a large mode field optical fiber or a single mode optical fiber.

[0017] A second aspect of the present invention provides a laser, comprising the optical fiber beam combining device described in any one of the above embodiments.

[0018] Compared with the prior art, the utility model has the following beneficial effects: the utility model provides a fiber beam combining device and a laser, wherein the first laser beam combiner is used to fuse the first sub-fibers of multiple first fiber lasers into a first fiber, and then couple the first fiber and the second fiber, and adopt a step-by-step fusion coupling method to form a combined laser and output it, thereby avoiding the situation where the fiber deformation caused by coupling the diameters of multiple first sub-fibers and multiple second fibers is avoided, so as to reduce signal loss, improve product quality, and reduce heat accumulation caused by beam combining. In this process, the diameter of the transition fiber gradually increases to the diameter of the output fiber, thereby reducing the cladding light and filtering out the return light in the output fiber, avoiding fiber transition corrosion, reducing the breakage of the output fiber, and improving the toughness of the output fiber. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a schematic diagram of the structure of the optical fiber bundle combining device provided in some embodiments of the utility model;

[0021] Figure 2 It is a schematic structural diagram of a second laser beam combiner of an optical fiber beam combining device provided in some embodiments of the present utility model.

[0022] Description of main component symbols;

[0023] 100-fiber beam combining device; 110-first fiber laser; 111-first sub-fiber; 120-second fiber laser; 121-second optical fiber; 130-first laser beam combiner; 131-first optical fiber; 140-second laser beam combiner; 141-transition optical fiber; 1411-coupling section; 1412-pumping section; 142-output optical fiber; 150-film stripper. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0027] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the utility model product is usually placed when in use, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0028] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0029] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In conjunction with the accompanying drawings, some embodiments of the present invention are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0031] Example 1

[0032] refer to Figure 1 As shown, an embodiment of the present application provides a fiber beam combining device 100 , which includes a first fiber laser 110 , a second fiber laser 120 , a first laser beam combiner 130 , and a second laser beam combiner 140 .

[0033] Specifically, combined Figure 1 and Figure 2As shown, a plurality of first fiber lasers 110 are used to generate Gaussian laser beams, and the first fiber lasers 110 include a first sub-fiber 111; a plurality of second fiber lasers 120 are used to generate ring laser beams, and the second fiber lasers 120 include a second fiber 121; a first laser beam combiner 130 is capable of fusing the plurality of the first sub-fibers 111 to the first fiber 131; a second laser beam combiner 140 is capable of combining the ring laser beam and the Gaussian laser beam into a combined laser beam, and the second laser beam combiner 140 includes a transition fiber 141 and an output fiber 142, and the first fiber 131 and the plurality of the second fibers 121 are respectively coupled to the transition fiber 141, and the diameter of the transition fiber 141 is from the diameter of the output fiber 142 to the diameter of the output fiber 142. The diameter of the first optical fiber 110 gradually increases. The first laser combiner 130 is used to fuse the first sub-fibers 111 of the multiple first optical fiber lasers 110 into the first optical fiber 131, and then couple the first optical fiber 131 and the second optical fiber 121. A step-by-step fusion coupling method is adopted to form a combined laser and output it, so as to avoid the situation where the optical fiber deformation caused by coupling the diameters of the multiple first sub-fibers 111 and the multiple second optical fibers 121 is avoided, so as to reduce signal loss, improve product quality, and reduce heat accumulation caused by beam combining. In this process, the diameter of the transition optical fiber 141 to the diameter of the output optical fiber 142 gradually increases, so as to reduce the cladding light and filter out the return light in the output optical fiber 142, avoid optical fiber transition corrosion, reduce the breakage of the output optical fiber 142, and improve the toughness of the output optical fiber 142.

[0034] Specifically, refer to Figure 1 As shown, a plurality of the second optical fiber lasers 120 are arranged around the first laser combiner 130. When the first optical fiber 131 and the plurality of second optical fibers 121 are respectively coupled to the transition optical fiber 141, the situation in which the coupling is affected by the length of the second optical fiber 121 of the second optical fiber laser 120, or the situation in which the second optical fiber 121 and the first optical fiber 131 are entangled with each other and cause obstruction is reduced, so as to facilitate the combination of the annular laser beam of the second optical fiber laser 120 and the Gaussian laser beam of the first laser combiner 130, reduce signal loss, and improve the use stability of the optical fiber combining device 100.

[0035] In one embodiment, specifically, Figure 1 As shown, the optical fiber beam combining device 100 further includes a plurality of strippers 150, one of the strippers 150 corresponds to one of the second optical fiber lasers 120, that is, one stripper 150 can correspond to one of the second optical fibers 121. It can be understood that the stripper mainly functions to remove the reverse cladding light of the second optical fiber 121, and the stripper is used to process the second optical fiber 121 before coupling to improve the quality of the coupled laser.

[0036] It should be noted that fiber coupling is the precise docking of two corresponding end faces of optical fibers so that the light energy output by the transmitting optical fiber can be coupled to the receiving optical fiber to the maximum extent, and the optical link is inserted to reduce the light path loss. The fiber coupling method can be to use multiple light beams to fuse and then taper to aggregate the fiber cores together to achieve optical coupling.

[0037] In one embodiment, specifically, the transition optical fiber 141 and the output optical fiber 142 each include a core and a cladding, the cladding is wrapped around the core, the core corresponds to the first optical fiber 131, and the cladding corresponds to a plurality of second optical fibers 121, respectively. Accordingly, the first optical fiber 131 corresponds to the position of the core, and each second optical fiber 121 corresponds to the position of the cladding. Optionally, the transition optical fiber 141 and the output optical fiber 142 also include a coating layer, the coating layer is wrapped around the side of the cladding away from the core, and the coating layer can be a layer of elastic coating cured by ultraviolet light, which is used to protect the surface of the optical fiber from gas dust and bumps, so that it has a certain anti-microbend performance to reduce the situation where the optical fiber is contaminated by dust.

[0038] Optionally, the output optical fiber 142 is a large mode field optical fiber or a single mode optical fiber. It is understood that a large mode field optical fiber is an optical fiber with a core diameter larger than that of a pure single mode optical fiber and allows only one or several spatial propagation modes, and has the characteristics of being able to withstand high average power, low nonlinearity, being able to withstand high peak power, low optical fiber loss, and no high-order mode cutoff, and the mode field diameter being independent of wavelength. Single mode optical fiber has small inter-modal dispersion and good stability, and can be preferably used in long-distance communications.

[0039] In summary, the first laser combiner 130 of the fiber combining device 100 is used to fuse the first sub-fibers 111 of multiple first fiber lasers 110 into a first optical fiber 131, and then couple the first optical fiber 131 and the second optical fiber 121, and adopt a step-by-step fusion coupling method to form a combined laser and output it, so as to avoid coupling the diameters of multiple first sub-fibers 111 and multiple second optical fibers 121 to cause optical fiber deformation, so as to reduce signal loss, improve product quality, and reduce heat accumulation caused by beam combining. In this process, the diameter of the transition optical fiber 141 gradually increases to the diameter of the output optical fiber 142, so as to reduce the cladding light and filter out the return light in the output optical fiber 142, avoid optical fiber transition corrosion, reduce the breakage of the output optical fiber 142, and improve the toughness of the output optical fiber 142.

[0040] Example 2

[0041] refer to Figure 1As shown, an embodiment of the present application provides another fiber beam combining device 100 , which includes a first fiber laser 110 , a second fiber laser 120 , a first laser beam combiner 130 , and a second laser beam combiner 140 .

[0042] Specifically, combined Figure 1 and Figure 2 As shown, a plurality of first fiber lasers 110 are used to generate Gaussian laser beams, and the first fiber lasers 110 include a first sub-fiber 111; a plurality of second fiber lasers 120 are used to generate ring laser beams, and the second fiber lasers 120 include a second optical fiber 121. A first laser combiner 130 can fuse the plurality of the first sub-fibers 111 to a first optical fiber 131, and the plurality of the first sub-fibers 111 are firstly fused to combine the Gaussian laser beams.

[0043] Specifically, the second laser beam combiner 140 is capable of combining the annular laser beam and the Gaussian laser beam into a combined laser beam. The second laser beam combiner 140 includes a transition fiber 141 and an output fiber 142. The first optical fiber 131 and the plurality of second optical fibers 121 are respectively coupled to the transition fiber 141, and the diameter of the transition fiber 141 gradually increases to the diameter of the output fiber 142. The first laser beam combiner 130 is used to fuse the first sub-fibers 111 of the plurality of first fiber lasers 110 into the first optical fiber 131, and then fuse the first sub-fibers 111 of the plurality of first fiber lasers 110 into the first optical fiber 131. An optical fiber 131 is coupled with a second optical fiber 121 by adopting a step-by-step fusion coupling method to form a combined laser beam and output it, thereby avoiding the situation where the optical fiber deformation caused by coupling the diameters of multiple first sub-optical fibers 111 and multiple second optical fibers 121 is avoided, so as to reduce signal loss, improve product quality, and reduce heat accumulation caused by beam combining. In this process, the diameter of the transition optical fiber 141 to the diameter of the output optical fiber 142 is gradually increased, reducing the cladding light and filtering the return light in the output optical fiber 142, avoiding the transition corrosion of the optical fiber and reducing the breakage of the output optical fiber 142.

[0044] Specifically, refer to Figure 1 As shown, a plurality of the second optical fiber lasers 120 are arranged around the first laser combiner 130. When the first optical fiber 131 and the plurality of second optical fibers 121 are respectively coupled to the transition optical fiber 141, the coupling is affected by the length of the second optical fiber 121 of the second optical fiber laser 120, or the obstruction caused by the entanglement of the second optical fiber 121 and the first optical fiber 131 is reduced, so as to facilitate the combination of the annular laser beam of the second optical fiber laser 120 and the Gaussian laser beam of the first laser combiner 130.

[0045] In one embodiment, specifically, Figure 1As shown, the optical fiber combining device 100 further includes a plurality of film strippers 150 , and one film stripper 150 corresponds to one second optical fiber laser 120 , that is, one film stripper 150 may correspond to one second optical fiber 121 .

[0046] In one embodiment, specifically, the transition optical fiber 141 and the output optical fiber 142 both include a core and a cladding, the cladding is wrapped around the core, the core corresponds to the first optical fiber 131, and the cladding corresponds to the plurality of second optical fibers 121, respectively. Accordingly, the first optical fiber 131 corresponds to the position of the core, and each second optical fiber 121 corresponds to the position of the cladding. It can be understood that during the optical fiber coupling process, multiple optical fibers are coupled into one optical fiber, and the positions of the multiple optical fibers before coupling and the one optical fiber after coupling can be corresponding.

[0047] Exemplarily, the number of the second optical fibers 121 is six, and the six second optical fibers 121 are disposed around the circumference of one first optical fiber 131 .

[0048] Optionally, the transition optical fiber 141 and the output optical fiber 142 also include a coating layer, which is wrapped around the side of the cladding away from the core. The coating layer can be a layer of elastic coating cured by ultraviolet light to protect the surface of the optical fiber from gas dust and bumps, so that it has a certain anti-micro-bending performance to reduce the contamination of the optical fiber by dust.

[0049] Optionally, the output optical fiber 142 is a large mode field optical fiber or a single mode optical fiber.

[0050] Optionally, refer to Figure 2 As shown, the transition optical fiber 141 includes a coupling section 1411 and a pump section 1412. The coupling section 1411 is connected to the output optical fiber 142 through the pump section 1412. The coupling section 1411 can be fused and tapered with the first optical fiber 131 and multiple second optical fibers 121. The diameter of the coupling section 1411 gradually increases to the diameter of the pump section 1412, so as to filter out the returned light brought by the coupling section 1411, reduce the amount of corrosion to the optical fiber, protect the optical fiber combining device 100, reduce the heat accumulated in the optical path of the coupling section 1411, and improve the toughness of the output optical fiber 142.

[0051] In one embodiment, specifically, the diameter of the first optical fiber 131 is not greater than the diameter of the core, that is, the diameter of the first optical fiber 131 is less than or equal to the diameter of the core, and the diameter of the second optical fiber 121 is not greater than the thickness of the cladding, that is, the diameter of the second optical fiber 121 is less than or equal to the thickness of the cladding, which can reduce the cladding light and the return light and reduce the loss of the optical path.

[0052] Optionally, the diameter of the first optical fiber 131 is D1, and the diameter of the core is D2, satisfying 0.7D2≤D1≤D2, that is, the diameter D1 of the first optical fiber 131 is less than or equal to the diameter D2 of the core, and the diameter D1 of the first optical fiber 131 is greater than or equal to 0.7D2. When the first optical fiber 131 is coupled to the transition optical fiber 141, the diameter of the first optical fiber 131 is not greater than the diameter of the core. From the first optical fiber 131 to the core of the transition optical fiber 141, local heat accumulation is reduced to cause breakage or even damage of the coupling section 1411. However, the diameter D1 of the first optical fiber 131 needs to be greater than or equal to 0.7D2 to reduce the loss of optical signals when transmitting signals. Exemplarily, D1 is 35um and D2 is 50um. At this time, when the first optical fiber 131 is coupled to the core of the transition optical fiber 141, the diameter of the first optical fiber 131 is D1 to ensure that the optical signal can be transmitted more conveniently, so as to avoid the large difference between the diameter of the first optical fiber 131 and the diameter of the core, which may cause light leakage or loss of the optical signal. In addition, D1 can also be 50um, which can ensure that the heat accumulation in the core from the first optical fiber 131 to the transition optical fiber 141 is reduced, and the core of the transition optical fiber 141 is reduced from heating and burning. Of course, the sizes of D1 and D2 are not limited to this, and can be any value between 35um and 50um. In other embodiments, when D2 is 55um, D1 can also be 55um; when D2 is 40um, D1 can also be 28um, 30um, 35um, 38um, 40um, etc., which will not be listed here.

[0053] Optionally, the diameter of the second optical fiber 121 is D3, and the thickness of the cladding is D4, satisfying 0.8D4≤D3≤D4, that is, the diameter D3 of the second optical fiber 121 is less than or equal to the thickness D4 of the cladding, and the diameter D3 of the second optical fiber 121 is greater than or equal to 0.8D4. When the second optical fiber 121 is coupled to the cladding of the transition optical fiber 141, the diameter of the second optical fiber 121 is not greater than the thickness of the cladding, from the second optical fiber 121 to the cladding of the transition optical fiber 141, so as to reduce local heat accumulation and cause damage to the connection position of the coupling section 1411, affecting the fusion effect, but the diameter D1 of the first optical fiber 131 needs to be greater than or equal to 0.7D2 to reduce the loss of optical signals when transmitting signals, so as to ensure the integrity of optical signal transmission. Exemplarily, D4 is 150um and D3 is 120um. At this time, when the second optical fiber 121 is coupled to the cladding of the transition optical fiber 141, the diameter of the second optical fiber 121 is D3 to ensure that the optical signal can be transmitted relatively completely, so as to avoid the large difference between the diameter of the second optical fiber 121 and the thickness of the cladding affecting the lossless transmission of the optical signal. In addition, D3 can also be 150um, which can ensure that the heat accumulation in the cladding from the second optical fiber 121 to the transition optical fiber 141 is reduced, and the heat accumulation in the cladding of the transition optical fiber 141 is reduced, which may cause the connection of the transition optical fiber 141 to break. Of course, the size of D3 is not limited to this, and can be any value between 120um and 150um. In other embodiments, when D4 is 130um, D3 can also be 120um; when D4 is 145um, D3 can also be 116um, 120um, 130um, 135um, 145um, etc., which will not be listed here.

[0054] Example 3

[0055] An embodiment of the utility model further provides a laser, including the fiber beam combining device 100 in embodiment 1 or embodiment 2. The laser may also include other laser devices. The laser including the fiber beam combining device 100 has all the beneficial effects of the fiber beam combining device 100, which will not be described in detail here.

[0056] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limiting, and thus other examples of the exemplary embodiments may have different values.

[0057] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. An optical fiber beam combining device, characterized in that: include: A plurality of first fiber lasers, for generating Gaussian laser beams, wherein the first fiber lasers include first sub-fibers; a plurality of second fiber lasers for generating annular laser beams, wherein the second fiber lasers include second optical fibers; a first laser beam combiner capable of fusing a plurality of the first sub-optical fibers to a first optical fiber; The second laser beam combiner is capable of combining the annular laser beam and the Gaussian laser beam into a combined laser beam. The second laser beam combiner includes a transition fiber and an output fiber. The first fiber and a plurality of the second fibers are respectively coupled to the transition fiber, and the diameter of the transition fiber gradually increases to the diameter of the output fiber.

2. The optical fiber bundle combining device according to claim 1, characterized in that: A plurality of the second fiber lasers are disposed around the first laser beam combiner.

3. The optical fiber bundle combining device according to claim 2, characterized in that: It also includes a plurality of film strippers, and one of the film strippers corresponds to one of the second fiber lasers.

4. The optical fiber bundle combining device according to claim 1, characterized in that: The transition optical fiber and the output optical fiber both include a core and a cladding, the cladding is wrapped around the core, the core corresponds to the first optical fiber, and the cladding corresponds to a plurality of the second optical fibers respectively.

5. The optical fiber bundle combining device according to claim 4, characterized in that: The transition optical fiber and the output optical fiber further include a coating layer, wherein the coating layer is wrapped around a side of the cladding away from the core.

6. The optical fiber combining device according to claim 4, characterized in that: The diameter of the first optical fiber is D1, and the diameter of the core is D2, satisfying 0.7D2≤D1≤D2.

7. The optical fiber bundle combining device according to claim 4, characterized in that: The diameter of the second optical fiber is D3, and the thickness of the cladding is D4, satisfying 0.8D4≤D3≤D4.

8. The optical fiber bundle combining device according to any one of claims 1 to 7, characterized in that: The transition optical fiber includes a coupling section and a pump section. The coupling section is connected to the output optical fiber through the pump section, and the diameter gradually increases from the coupling section to the pump section.

9. The optical fiber bundle combining device according to any one of claims 1 to 7, characterized in that: The output optical fiber is a large mode field optical fiber or a single mode optical fiber.

10. A laser, characterized in that: The optical fiber bundle combining device comprises the optical fiber bundle combining device as claimed in any one of claims 1 to 9.

Images