High-efficiency and high-stability space coupling system of solid-core optical fiber and hollow-core anti-resonance optical fiber

Abstract

The invention provides a high-efficiency and high-stability space coupling system for a solid-core optical fiber and a hollow-core anti-resonance optical fiber, and belongs to the field of optics. After output information of the hollow-core anti-resonance optical fiber is detected, the output information is transmitted to the instruction input module so as to regulate and control the coupling module, automatic adjustment of the system is achieved, and the system can operate stably. In the coupling module, laser output by a solid optical fiber is subjected to beam shaping through an optical fiber output device and a curvature mirror group, so that the laser is matched with a hollow-core anti-resonance optical fiber mode field, and then the laser is injected into the hollow-core anti-resonance optical fiber after being subjected to stray light absorption and filtration through a gradient saturable absorber diaphragm; besides, the hollow-core anti-resonance optical fiber is clamped by a clamp with a refrigeration function and is placed on a programmable electric control displacement table with a thermal focal movement active compensation function, and high-power, high-efficiency and high-stability coupling is realized through accurate adjustment. The problem that the hollow-core optical fiber is damaged due to stray light, light spot distortion, light beam jitter and the like under high-power laser transmission is effectively solved.

Description

Technical Field

[0001] The invention relates to the field of optical technology, and in particular to a high-efficiency and high-stability spatial coupling system of a solid-core optical fiber and a hollow-core anti-resonance optical fiber. Background Art

[0002] With the widespread application of fiber lasers in communications, sensing and other fields, the output power of high-power narrow-linewidth fiber lasers has been continuously breaking through. However, due to the nonlinear effects of optical fiber materials such as stimulated Brillouin scattering and stimulated Raman scattering, narrow linewidth and high power cannot be achieved at the same time. Therefore, hollow-core antiresonant optical fibers with advantages such as low nonlinear coefficient and high damage threshold have emerged.

[0003] Hollow-core antiresonant fiber is an optical fiber that uses the antiresonance effect to limit and guide the transmission of light in the core. Its core is an air core, and periodically arranged air holes are used to suppress the transmission of light into the cladding. Since the core of the hollow-core fiber is an air core, fusion with traditional solid optical fibers will cause problems such as collapse at the melting point and large fusion loss. Existing technologies mostly use spatial coupling methods for transmission. However, simple spatial coupling systems are plagued by problems such as beam jitter, stray light interference, low coupling efficiency, and thermal focal shift, and there is a great risk of damage during high-power coupled transmission. Existing methods to solve stray light interference are mostly to use hard material apertures such as metal or ceramics to intercept, but it is difficult to achieve a perfect match between the aperture size and the transmitted laser, and it is easy to have problems such as incomplete stray light filtering, diffraction effects, and severe power loss. Therefore, designing an anti-interference and anti-jitter coupling device to achieve efficient and stable transmission of high-power lasers is one of the key issues to be solved in this field.

[0004] In view of this, it is necessary to design a high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core antiresonant optical fiber to solve the above problems. Summary of the invention

[0005] In view of the technical problems existing in the background technology, the present application provides a high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber, aiming to solve the technical problems that the existing coupling system is seriously affected by stray light interference, spot distortion interference, and thermal focus shift.

[0006] The embodiment of the present application provides a high-efficiency and high-stability spatial coupling system of a solid-core optical fiber and a hollow-core anti-resonant optical fiber, comprising:

[0007] A coupling module, the coupling module comprising: a solid optical fiber, an optical fiber output device fused with the solid optical fiber, a coupling curvature mirror group located at one end of the optical fiber output device, a saturable absorber aperture located at one end of the coupling curvature mirror group, a programmable electrically controlled displacement stage located at one end of the saturable absorber aperture, and a hollow core anti-resonant optical fiber running through the programmable electrically controlled displacement stage;

[0008] A section of the hollow-core anti-resonance optical fiber close to the saturable absorber aperture is placed inside the programmable electrically controlled translation stage, and the remaining section of the hollow-core anti-resonance optical fiber is located outside the programmable electrically controlled translation stage;

[0009] The optical fiber output device is coaxial with the coupling curvature mirror assembly;

[0010] A detection module, used for monitoring and feeding back temperature information of the coupling module and output power information of the hollow-core anti-resonance optical fiber;

[0011] The instruction input module is used to receive data transmitted by the detection module and to send instructions to control the coupling module.

[0012] In this embodiment, a coupling module, a detection module, and a command input module are set up, wherein the detection module monitors the information of the coupling module in real time, and then after the information is transmitted to the command input module, instructions are sent to regulate the coupling module, thereby realizing automatic adjustment of the system. This helps to quickly adjust to the optimal working state when the environment changes or the system performance fluctuates, so that the system can operate stably.

[0013] The coupling optical path constructed by modular components consisting of solid optical fiber, optical fiber output, coupling curvature mirror group, saturable absorber aperture, hollow-core antiresonant optical fiber, and programmable electrically controlled translation stage set in the coupling module can realize high-efficiency energy transmission between solid-core optical fiber and hollow-core antiresonant optical fiber, reduce energy loss, and improve the performance of the overall system.

[0014] In some embodiments, the optical fiber output device is used to perform preliminary beam expansion and preliminary shaping on the transmitted laser beam; and / or,

[0015] The side of the optical fiber output device fused with the solid optical fiber is a plane, and the other side of the optical fiber output device is coated with a high-transmittance film.

[0016] In some embodiments, the coupling curvature mirror set is used to shape the transmitted high-power laser beam; and / or,

[0017] The coupling curvature mirror group includes one of a transmission mirror group and a reflection mirror group.

[0018] In some embodiments, the saturable absorber aperture is used to perform nonlinear absorption on the transmitted laser light to filter out stray light and interference light; and / or,

[0019] The center of the saturable absorber aperture is hollow;

[0020] The center of the saturable absorber aperture is in a gradual changing state along the radial direction;

[0021] The gradual change state includes one of a gradual change in doping concentration and a gradual change in thickness; and / or, surfaces at both ends of the saturable absorber aperture are coated with a dielectric film with high transmittance to the transmitted laser.

[0022] In this embodiment, compared with the traditional hard-edge aperture, a saturable absorber aperture is used for beam shaping, thereby reducing the diffraction effect and weakening the high-order modes to a certain extent, effectively solving the hollow-core optical fiber damage problem caused by stray light, spot distortion, beam jitter, etc. under high-power laser transmission.

[0023] In some embodiments, a programmable electrically controlled translation stage holding the hollow core anti-resonant optical fiber is used for active compensation of thermal focal shift under high power transmission conditions.

[0024] The incident end of the hollow core anti-resonance optical fiber is located at the focus of the transmitted laser;

[0025] The outer cladding surface of a section of the hollow-core antiresonant optical fiber placed in the programmable electric-controlled displacement stage is etched with periodic textures to destroy the waveguide structure between the air hole and the cladding.

[0026] In some embodiments, the high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber further includes: a cooling module for regulating the working temperature of the coupling module after receiving information from the instruction input module; and / or,

[0027] The working temperature required to be loaded by the saturable absorber aperture and the working temperature required to be loaded by the hollow core antiresonant optical fiber are regulated by the refrigeration module; and / or,

[0028] The refrigeration module comprises a refrigeration fixture; and / or,

[0029] The saturable absorber aperture and a section of hollow-core antiresonant optical fiber placed in the programmable electrically controlled translation stage are respectively clamped in the refrigeration fixture.

[0030] In some embodiments, the instructions include: regulating the operating temperature required to be loaded on the saturable absorber aperture, regulating the operating temperature required to be loaded on the hollow-core antiresonant fiber, regulating the power parameters of the incident laser, regulating the position of the programmable electrically-controlled displacement stage, and regulating the position of the hollow-core antiresonant fiber in a high-power transmission state by means of the programmable electrically-controlled displacement stage.

[0031] In some embodiments, the detection module includes a temperature sensor located on the coupling module and a power detector located at the output end of the hollow core anti-resonance optical fiber.

[0032] In some embodiments, the temperature sensor comprises: a temperature sensor 1 located on one side of the coupling curvature mirror assembly, a temperature sensor 2 located on one side of the hollow-core anti-resonant optical fiber; and / or,

[0033] The second temperature sensor is close to the incident end of the hollow core anti-resonance optical fiber; and / or,

[0034] The temperature sensor 1 is used to detect the temperature rise data of the coupling curvature mirror group; the temperature sensor 2 is used to monitor the working temperature of the hollow core anti-resonance optical fiber; and / or,

[0035] The power detector is used to monitor the output light power of the hollow core anti-resonance optical fiber.

[0036] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings used in the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0038] Figure 1 This is a schematic diagram of a packaging module for packaging a high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber in an embodiment of the present application.

[0039] Figure 2 Schematic diagram of a high-efficiency and high-stability spatial coupling system of a solid-core optical fiber and a hollow-core antiresonant optical fiber in an embodiment of the present application.

[0040] Figure 3 This is a schematic diagram of the operation of each module in the high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber in an embodiment of the present application.

[0041] Reference numerals

[0042] 11. Metal packaging base; 12. Metal packaging cover; 2. Solid optical fiber; 3. Optical fiber output; 4. Coupling curvature mirror group; 5. Saturable absorber aperture; 6. Hollow core antiresonant optical fiber; 7. Programmable electric control displacement stage; 8. Power detector; 91. Temperature sensor one; 92. Temperature sensor two; 10. Command input module. DETAILED DESCRIPTION

[0043] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0045] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0046] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0047] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0048] In the prior art, the way to solve the interference of stray light is to use a hard material aperture such as metal or ceramic to intercept, but it is difficult to perfectly match the aperture size with the transmitted laser, which may cause problems such as incomplete filtering of stray light, diffraction effect, and severe power loss. Therefore, it is particularly important to prepare an anti-interference and anti-jitter device to achieve efficient and stable transmission of high-power lasers.

[0049] In order to solve the above-mentioned technical problems, the present application provides a high-efficiency and high-stability spatial coupling system of a solid-core optical fiber and a hollow-core antiresonant optical fiber, wherein, after the beam is shaped by an optical fiber output device 3 and a coupling curvature mirror group 4, the stray light is filtered out and the high-order modes are weakened by a saturable absorber aperture 5, and then coupled into a hollow-core antiresonant optical fiber 6, and the position is finely adjusted and active compensation for thermal focus shift under high-power transmission conditions is achieved by controlling a programmable electrically controlled displacement stage 7 that clamps the hollow-core antiresonant optical fiber (i.e., the hollow-core optical fiber), thereby improving the coupling efficiency and reducing the risk of damage to the hollow-core antiresonant optical fiber 6.

[0050] Please refer to Figures 1 to 3 The embodiment of the present application provides a high-efficiency and high-stability spatial coupling system of a solid-core optical fiber and a hollow-core anti-resonant optical fiber, comprising:

[0051] A coupling module, the coupling module comprising: a solid optical fiber 2, an optical fiber output device 3 fused with the solid optical fiber 2, a coupling curvature mirror group 4 located at one end of the optical fiber output device 3, a saturable absorber aperture 5 located at one end of the coupling curvature mirror group 4, a programmable electrically controlled displacement stage 7 located at one end of the saturable absorber aperture 5, and a hollow core anti-resonant optical fiber 6 running through the programmable electrically controlled displacement stage 7;

[0052] A section of the hollow-core anti-resonance optical fiber 6 close to the saturable absorber aperture 5 is fixedly placed in the programmable electric-controlled translation stage 7, and the remaining section of the hollow-core anti-resonance optical fiber 6 is located outside the programmable electric-controlled translation stage 7;

[0053] The optical fiber output device 3 is coaxial with the coupling curvature lens group 4;

[0054] A detection module, used to monitor and feed back the temperature information of the coupling module and the output power information of the hollow-core anti-resonance optical fiber 6;

[0055] The command input module 10 is used to receive the data transmitted by the detection module; then the received data is converted into a sending command to control the coupling module; the command includes: regulating the ideal working temperature required for loading the saturable absorber aperture 5, regulating the ideal working temperature required for loading the hollow core antiresonant fiber 6, regulating the power parameters of the incident laser, regulating the position of the programmable electrically controlled displacement stage 7, and regulating the position of the hollow core antiresonant fiber 6 under the high power transmission state by the programmable electrically controlled displacement stage 7.

[0056] A refrigeration module; used for adjusting the working temperature of the coupling module after receiving information from the instruction input module 10; the working temperature required to be loaded by the saturable absorber aperture 5 and the working temperature required to be loaded by the hollow-core antiresonant optical fiber 6 are adjusted by the refrigeration module; the refrigeration module is a refrigeration fixture; the saturable absorber aperture 5 and a section of the hollow-core antiresonant optical fiber 6 placed in the programmable electrically-controlled displacement stage 7 are respectively clamped in the refrigeration fixture; the hollow-core antiresonant optical fiber 6 is clamped in the refrigeration fixture and placed on the programmable electrically-controlled displacement stage 7.

[0057] In the technical solution of the embodiment of the present application, a coupling module, a detection module, and an instruction input module 10 are set, wherein the detection module monitors the information of the coupling module in real time, and then after the information is transmitted to the instruction input module 10, instructions are sent to regulate the coupling module, thereby realizing automatic adjustment of the system. This helps to quickly adjust to the optimal working state when the environment changes or the system performance fluctuates, so that the system can operate stably.

[0058] The coupling optical path constructed by the modular components composed of the solid core optical fiber 2, the optical fiber output device 3, the coupling curvature mirror group 4, the saturable absorber aperture 5, and the hollow core anti-resonant optical fiber 6 arranged in the coupling module can realize high-efficiency energy transmission between the solid core optical fiber and the hollow core anti-resonant optical fiber 6, reduce energy loss, and improve the performance of the overall system.

[0059] Furthermore, in some embodiments, the optical fiber output device 3 is used to perform preliminary beam expansion and preliminary shaping of the laser beam transmitted therethrough;

[0060] The side of the optical fiber output device 3 fused with the solid optical fiber 2 is a plane, and the other side of the optical fiber output device 3 is coated with a high-transmittance film; the other side of the optical fiber output device 3 includes one of a plane and a curved surface.

[0061] Further, in some embodiments, the coupling curvature mirror group 4 is used to shape the beam of the high-power laser transmitted thereto;

[0062] The coupling curvature mirror group 4 is composed of a plurality of curvature mirrors; the coupling curvature mirror group 4 includes one of a transmission mirror group and a reflection mirror group.

[0063] Furthermore, in some embodiments, the saturable absorber aperture 5 is used to nonlinearly absorb the laser light transmitted therethrough to filter out stray light and interference light; in addition, the saturable absorber aperture 5 can also be used to weaken the high-order mode components in the laser light;

[0064] The center of the saturable absorber aperture 5 is hollow;

[0065] The center of the saturable absorber aperture 5 is in a gradual change state along the radial direction;

[0066] The gradual change state includes one of a doping concentration gradual change and a thickness gradual change (thickness: along the irradiation direction of the laser in the saturable absorber aperture 5; gradual change: when the laser hits the center of the saturable absorber aperture 5, the center is taken as the origin, and the gradual change is performed radially along the origin to the direction perpendicular to the laser irradiation, for example: first, the incident thickness at the origin is 0; when the radius reaches r1, the incident thickness becomes h1; when the radius reaches r2, the incident thickness becomes h2; during this period, the incident thickness along the radial direction of the saturable absorber aperture 5 gradually changes from h1 to h2);

[0067] In addition, when the saturable absorber aperture 5 has a radially gradient thickness, it can equivalently replace part of the coupling curvature mirror group 4 .

[0068] The surfaces of both ends of the saturable absorber aperture 5 are coated with a dielectric film having a high transmittance to the transmitted laser.

[0069] In the technical solution of the embodiment of the present application, by using a saturable absorber aperture 5 for beam shaping, the diffraction effect is reduced and the high-order modes are weakened to a certain extent, effectively solving the hollow-core optical fiber damage problem caused by stray light, spot distortion, beam jitter, etc. under high-power laser transmission.

[0070] Furthermore, in some embodiments, the programmable electrically controlled translation stage 7 holding the hollow core anti-resonant optical fiber 6 is used for active compensation of thermal focal shift under high power transmission conditions;

[0071] The core of the hollow-core anti-resonance optical fiber 6 is an air core, and the light-guiding transmission principle is: the periodically arranged air holes inhibit the transmission of light to the cladding, and the structure of the hollow-core anti-resonance optical fiber 6 includes one of a single-ring structure and a double-nested structure;

[0072] The incident end of the hollow core anti-resonance optical fiber 6 is located at the focus of the transmitted laser;

[0073] The coating layer of a section of the hollow-core anti-resonance optical fiber 6 placed in the programmable electric-controlled displacement stage 7 is stripped, and a carbon dioxide fusion splicer is used to etch periodic patterns on the surface of the outer cladding of the section of the hollow-core anti-resonance optical fiber 6 to destroy the waveguide structure between the air hole and the outer cladding.

[0074] Furthermore, in some embodiments, the programmable electric-controlled displacement stage 7 is connected to a driver via a cable, and the driver is controlled by the instruction input module 10 to adjust the position of the programmable electric-controlled displacement stage 7;

[0075] The programmable electric-controlled displacement stage 7 adjusts the hollow-core anti-resonant optical fiber 6 to achieve high-efficiency coupling between the transmission laser and the hollow-core anti-resonant optical fiber 6 .

[0076] Further, in some embodiments, the detection module includes a temperature sensor located on the coupling module and a power detector 8 located at the output end of the hollow core anti-resonance optical fiber 6;

[0077] The temperature sensor includes: a temperature sensor 1 91 located on one side of the coupling curvature mirror group 4, and a temperature sensor 2 92 located on one side of the hollow core anti-resonance optical fiber 6;

[0078] The second temperature sensor 92 is close to the incident end of the hollow core anti-resonance optical fiber 6;

[0079] The temperature sensor 1 91 is used to detect the temperature rise data of the coupling curvature mirror group 4; the temperature sensor 2 92 is used to monitor the working temperature of the hollow core anti-resonance optical fiber 6;

[0080] The power detector 8 is used to monitor the output light power of the hollow core anti-resonance optical fiber 6 .

[0081] The following describes the assembly process and related adjustment principles of the high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber:

[0082] S1, using a fusion splicer to fusion-splice the solid optical fiber 2 and the optical fiber output device 3, optically assembling and adjusting the fusion-spliced ​​optical fiber output device 3, and fixing it on the metal packaging base 11; wherein the solid optical fiber is connected to the light source of the incident laser at the front end;

[0083] S2. Calculate and design the mode field parameters of the incident laser, the optical fiber output device 3, and the hollow-core antiresonant optical fiber 6, select an appropriate coupling curvature mirror group 4, optically adjust the coupling curvature mirror group 4 according to the design scheme, and fix it coaxially with the optical fiber output device 3 on the metal packaging base 11;

[0084] S3, designing the hollow diameter and the gradient doping concentration or gradient thickness parameters of the saturable absorber aperture 5 according to the beam size and beam power density after shaping by the coupling curvature lens group 4; after the design is completed, clamping the saturable absorber aperture 5 in a refrigeration fixture, and fixing it coaxially with the coupling curvature lens group 4 on the metal packaging base 11 through optical adjustment;

[0085] S4, a temperature sensor 91 is arranged on one side of the coupling curvature mirror group 4, and the temperature rise variation data of the coupling curvature mirror group 4 as the input laser power increases, and the data is matched one by one with the focal position data of the transmission laser;

[0086] S5, fix the hollow core anti-resonant optical fiber 6 placed in the refrigeration fixture on the programmable electric-controlled displacement stage 7, and fix the lower end of the programmable electric-controlled displacement stage 7 on the metal packaging base 11; set a temperature sensor 92 on the side close to the incident end of the hollow core anti-resonant optical fiber 6; the temperature sensor 92 is set on the top of the programmable electric-controlled displacement stage 7; in the state of inputting low-power laser, the programmable electric-controlled displacement stage 7 is controlled to fine-tune the position and direction to achieve efficient coupling output;

[0087] S6, controlling the temperature of the saturable absorber aperture 5 and the hollow-core antiresonant optical fiber 6 by means of a refrigeration module;

[0088] S7, input the temperature rise data of the coupling curvature mirror group 4 and the data of the position corresponding to the focus of the transmitted laser into the control program of the programmable electric-controlled displacement stage 7; during the high-power laser transmission process, the data collected by the temperature sensor 91 at the coupling curvature mirror group 4 is fed back to the instruction input module 10, and the instruction input module 10 sends instructions according to the received data and fine-tunes the position of the programmable electric-controlled displacement stage 7 to achieve active thermal focus compensation;

[0089] S8, the power detector 8 feeds back the detected coupled output power of the hollow-core anti-resonant optical fiber 6 in real time. When the light beam output from the optical fiber output device 3 shakes or deforms, it is intercepted by the saturable absorber aperture 5. The power detector 8 feeds back the light beam power reduction signal output by the hollow-core anti-resonant optical fiber 6 to the command input module 10, and the command input module 10 issues a command to stop the high-power laser input at the incident laser light source.

[0090] The high-efficiency and high-stability spatial coupling system of the solid-core optical fiber and the hollow-core anti-resonant optical fiber 6 is placed in a packaging module composed of a metal packaging base 11 and a metal packaging cover 12 .

[0091] In summary, the high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core antiresonant optical fiber provided by the present invention is configured with a coupling module, a detection module, and a command input module 10, wherein the detection module monitors the information of the coupling module in real time, and then after the information is transmitted to the command input module 10, a command is sent to regulate the coupling module, thereby realizing automatic adjustment of the system. This helps to quickly adjust to the optimal working state when the environment changes or the system performance fluctuates, so that the system can operate stably.

[0092] In addition, the coupling module is provided with a solid optical fiber 2, an optical fiber output device 3, a coupling curvature mirror group 4, a saturable absorber aperture 5, and a hollow core anti-resonant optical fiber 6. The coupling optical path constructed by such modular components can realize high-efficiency energy transmission between the solid core optical fiber and the hollow core anti-resonant optical fiber 6, thereby improving the performance of the overall system. The use of the saturable absorber aperture 5 also avoids the diffraction problem introduced by the traditional hard material aperture, and weakens the high-order mode to a certain extent, effectively solving the hollow core optical fiber damage problem caused by stray light, spot distortion, beam jitter, etc. under high-power laser transmission.

[0093] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber, characterized in that: include: A coupling module, the coupling module comprising: a solid optical fiber, an optical fiber output device fused with the solid optical fiber, a coupling curvature mirror group located at one end of the optical fiber output device, a saturable absorber aperture located at one end of the coupling curvature mirror group, a programmable electrically controlled displacement stage located at one end of the saturable absorber aperture, and a hollow core anti-resonant optical fiber running through the programmable electrically controlled displacement stage; A section of the hollow-core anti-resonance optical fiber close to the saturable absorber aperture is placed inside the programmable electrically controlled translation stage, and the remaining section of the hollow-core anti-resonance optical fiber is located outside the programmable electrically controlled translation stage; The optical fiber output device is coaxial with the coupling curvature mirror assembly; A detection module, used for monitoring and feeding back temperature information of the coupling module and output power information of the hollow-core anti-resonance optical fiber; The instruction input module is used to receive data transmitted by the detection module and to send instructions to control the coupling module.

2. The high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber according to claim 1, characterized in that: The optical fiber output device is used to perform preliminary beam expansion and preliminary shaping on the transmitted laser beam; and / or, The surface of the optical fiber output device fused with the solid optical fiber is a plane, and the other surface of the optical fiber output device is coated with a high-transmittance film.

3. The high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber according to claim 1, characterized in that: The coupling curvature mirror group is used to shape the transmitted high-power laser beam; and / or, The coupling curvature mirror group includes one of a transmission mirror group and a reflection mirror group.

4. The high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber according to claim 1, characterized in that: The saturable absorber aperture is used to perform nonlinear absorption on the transmitted laser light to filter out stray light and interference light; and / or, The center of the saturable absorber aperture is hollow; The center of the saturable absorber aperture is in a gradual changing state along the radial direction; The gradient state includes one of gradient doping concentration and gradient thickness; and / or, The surfaces of both ends of the saturable absorber aperture are plated with dielectric films with high transmittance to the transmitted laser.

5. The high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber according to claim 1, characterized in that: The programmable electrically controlled translation stage clamping the hollow core anti-resonant optical fiber is used for active compensation of thermal focal shift under high power transmission state.

6. The high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber according to claim 5, characterized in that: The incident end of the hollow core anti-resonance optical fiber is located at the focus of the transmitted laser; The outer cladding surface of a section of hollow-core anti-resonance optical fiber placed in the programmable electric-controlled displacement stage is etched with periodic textures to destroy the waveguide structure between the air hole and the cladding.

7. The high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber according to claim 1, characterized in that: Also includes: A cooling module, used for adjusting the working temperature of the coupling module after receiving the information from the instruction input module; and / or, The working temperature required to be loaded by the saturable absorber aperture and the working temperature required to be loaded by the hollow core antiresonant optical fiber are regulated by the refrigeration module; and / or, The refrigeration module comprises a refrigeration fixture; and / or, The saturable absorber aperture and a section of hollow-core antiresonant optical fiber placed in the programmable electrically controlled translation stage are respectively clamped in the refrigeration fixture.

8. The high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber according to claim 7, characterized in that: The instructions include: regulating the working temperature required to be loaded on the saturable absorber aperture, regulating the working temperature required to be loaded on the hollow-core antiresonant optical fiber, regulating the power parameters of the incident laser, regulating the position of the programmable electrically-controlled displacement stage, and regulating the position of the hollow-core antiresonant optical fiber under a high-power transmission state by means of the programmable electrically-controlled displacement stage.

9. The high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber according to claim 6, characterized in that: The detection module includes a temperature sensor located on the coupling module and a power detector located at the output end of the hollow-core anti-resonance optical fiber.

10. The high-efficiency and high-stability spatial coupling system of solid-core optical fiber and hollow-core anti-resonant optical fiber according to claim 9, characterized in that: The temperature sensor comprises: a temperature sensor 1 located at one side of the coupling curvature mirror group, a temperature sensor 2 located at one side of the hollow core anti-resonance optical fiber; and / or, The second temperature sensor is close to the incident end of the hollow core anti-resonance optical fiber; and / or, The temperature sensor 1 is used to detect the temperature rise data of the coupling curvature mirror group; the temperature sensor 2 is used to monitor the working temperature of the hollow core anti-resonance optical fiber; and / or, The power detector is used to monitor the output light power of the hollow core anti-resonance optical fiber.

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