A hollow-core optical fiber discharge fusion splicing platform and method for an active optical fiber cable

Abstract

The present invention discloses a hollow fiber discharge splicing platform and method for an active optical fiber cable, which includes a discharge splicing platform. The discharge splicing platform includes a splicing unit, a wind shield and an optical fiber fixture. The optical fiber fixture includes a bottom plate and a cover plate. A first optical fiber positioning groove and a second optical fiber positioning groove are arranged on the bottom plate. The first optical fiber positioning groove and the second optical fiber positioning groove are coaxially arranged. An image processing system and a pressing foot are arranged inside the wind shield. The present invention can complete the positioning of the optical fiber without loading the hollow optical fiber by means of two support points plus a limiting point, effectively improving the discharge splicing efficiency of the hollow anti-resonant optical fiber.

Description

Technical Field

[0001] The present invention relates to an active optical emission module, belonging to the technical field of optical modules, and particularly relates to a hollow fiber discharge welding platform and method for an active optical fiber cable. Background Art

[0002] As a new type of microstructure optical fiber, hollow core anti-resonant fiber (HC-ARF) exhibits broad application prospects in the fields of optical communication, laser transmission, sensing, etc. due to its excellent properties such as low loss, large bandwidth, and anti-nonlinearity. This fiber innovatively uses air as the optical transmission medium, breaking through the limitation of traditional fibers relying on glass fiber cores for transmission, and achieving significant improvements in multiple performance indicators. Especially in application scenarios such as high-power laser transmission, low-latency communication, and optical signal transmission in special environments, HC-ARF shows unique advantages.

[0003] However, the structural characteristics of HC-ARF pose severe challenges to its practical applications. Different from traditional fibers that use glass fiber cores as the transmission medium, the core transmission region of HC-ARF is air, and its cladding adopts a precise microstructure design, consisting of tiny air holes arranged along the fiber length to form a specific periodic structure, with a cross-section presenting a honeycomb state similar to a silicon filament mesh. Although this unique structural design achieves excellent optical performance, it also makes the connection and coupling of the fiber extremely difficult.

[0004] Currently, traditional methods such as mechanical connection and lens coupling are mainly used for fiber connection and coupling. These methods are quite mature when dealing with ordinary fibers, but face multiple technical challenges when applied to HC-ARF: First, due to the fine and complex air hole structure of HC-ARF, it is very difficult to achieve precise alignment during butt joint, and even a tiny deviation will result in serious transmission loss; Second, impurities such as dust and water vapor are easily introduced during the connection process. Once these impurities enter the air hole structure, they are not only difficult to remove but also seriously affect the transmission performance of the fiber; In addition, even if the initial connection is successfully achieved, due to the fragility of the structure, the mechanical stability of the connection point is often poor and is easily affected by environmental factors and the performance degrades.

[0005] These technical problems severely restrict the practical application and development of HC-ARF, making it difficult for this revolutionary new fiber to be widely promoted in actual engineering. Especially in commercial application scenarios that require stability and reliability, the connection problem of HC-ARF has become a technical bottleneck that cannot be ignored. Therefore, it is extremely urgent to develop new connection and coupling methods specifically for the characteristics of HC-ARF. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a hollow fiber discharge welding platform for an active optical fiber cable in view of the technical defects existing in the prior art. By means of a double support point plus a limit point, the fiber can be limited without loading the hollow fiber, effectively improving the discharge welding efficiency of the hollow anti-resonant fiber.

[0007] The technical solution adopted by the present invention to solve its technical problems is as follows: The present invention discloses a hollow fiber discharge welding platform for an active optical fiber cable, including a discharge welding platform. The discharge welding platform includes a fixedly arranged welding unit and an openable and closable wind shield. The arrangement positions of the welding unit and the wind shield correspond to each other. Fiber clamps with adjustable spatial positions are arranged on both sides of the welding unit. Each fiber clamp includes a bottom plate and a cover plate that can be opened and closed and is connected to the bottom plate. A first fiber positioning groove is arranged on the bottom plate, and a boss is arranged on the end surface of the bottom plate facing the welding unit. A second fiber positioning groove is arranged on the boss. The first fiber positioning groove and the second fiber positioning groove are coaxially arranged. Fiber avoidance holes are arranged on both sides of the wind shield. An image processing system and a pressing foot are arranged inside the wind shield. The pressing foot is located between the second fiber positioning grooves, and the second fiber positioning grooves are located between the first fiber positioning grooves. The pressing foot can cooperate with the first fiber positioning groove and the second fiber positioning groove to complete the limitation of the fiber without loading the fiber.

[0008] In a preferred embodiment of the present invention, the first fiber positioning groove is a U-shaped groove, and the second fiber positioning groove is a V-shaped groove.

[0009] In a preferred embodiment of the present invention, the width of the U-shaped groove corresponds to the fiber diameter, and the included angle of the V-shaped groove is , 60° ≤ ≤ 120°, the depth of the V-shaped groove is h, 0.5d ≤ h ≤ 1.5d, d is the outer diameter of the fiber, and the roughness of the two walls of the V-shaped groove is less than 10 nm.

[0010] In a preferred embodiment of the present invention, a guide seat for guiding the fiber to fall into the first fiber positioning groove is arranged on the bottom plate, and a guide hole is arranged on the guide seat.

[0011] In a preferred embodiment of the present invention, the cross-sectional shape of the guide hole is Y-shaped.

[0012] In a preferred embodiment of the present invention, two multi-axis motion platforms are symmetrically arranged on the discharge welding platform. The moving end of the multi-axis motion platform is connected to the fiber clamp, and the multi-axis motion platform is communicatively connected to the image processing system.

[0013] In a preferred embodiment of the present invention, the multi-axis motion platform includes at least one first linear displacement module that can be displaced along the axial direction of the optical fiber and at least one rotation module that can rotate circumferentially around the optical fiber.

[0014] In a preferred embodiment of the present invention, the welding unit includes two symmetrically arranged graphene electrode rods, and the arrangement direction of the two graphene electrode rods is perpendicular to the arrangement direction of the first optical fiber positioning groove.

[0015] In a preferred embodiment of the present invention, an ultraviolet glue curing system is further included.

[0016] The present invention also discloses a method for welding hollow-core optical fibers using a discharge welding platform. Open the wind shield and the optical fiber fixture; place two hollow-core optical fibers to be welded on the optical fiber fixture respectively, and keep the ports of the two hollow-core optical fibers between the V-groove of the optical fiber fixture and the graphene electrode rod; close the wind shield and the optical fiber fixture, the microscope image processing system collects the alignment angle of the two optical fibers and slowly approaches the two optical fibers by controlling the multi-axis motion platform, and rotates the optical fiber fixture to align the cores of the two hollow-core optical fibers; perform the welding work by generating arc discharge through the graphene electrode rod; after opening the wind shield, the multi-axis motion platform automatically generates a slight displacement to the left and right respectively (the pulling force of the displacement is 2N) to test the strength of the welding point. If the hollow-core optical fiber is not broken, it means that the strength of the welding point meets the requirements; use a glass capillary to wrap and fix the welding point of the welded hollow-core optical fiber, inject ultraviolet curing glue and then put it into the ultraviolet glue curing system for fixation.

[0017] The beneficial effects of the present invention are as follows: The present invention has the advantages of simple structure and high automation degree. It can conveniently, stably and efficiently realize the high-efficiency discharge welding of hollow-core anti-resonant optical fibers, and can play a good role in fixing and positioning the hollow-core anti-resonant optical fibers during the discharge welding process, improving the stability and repeatability of the discharge welding.

[0018] First of all, through the innovative adoption of a three-point positioning method with two support points (the first optical fiber positioning groove, the second optical fiber positioning groove) plus a limit point (the pressing foot), precise limiting of the optical fiber is achieved without applying additional load to the hollow-core optical fiber. This design significantly improves the discharge welding efficiency and effectively avoids the problem of optical fiber damage that may be caused by loading in the traditional method.

[0019] Secondly, the present invention adopts a combination structure of a carefully designed U-shaped groove and a V-shaped groove, where the width of the U-shaped groove matches the diameter of the optical fiber. The V-shaped groove has a specific included angle range (60° - 120°) and depth requirements (0.5d - 1.5d), and the surface roughness of the V-shaped groove wall is controlled below 10 nm. This structural design not only ensures the accuracy of optical fiber positioning but also minimizes the risk of scratching on the optical fiber surface.

[0020] Thirdly, the present invention adopts the design of a Y-shaped guiding hole, which, combined with the guiding function of the guiding seat, greatly improves the convenience and efficiency of the installation process of the hollow optical fiber. At the same time, the setting of the multi-axis motion platform enables precise adjustment of the optical fiber in the axial and circumferential directions. Combined with the real-time monitoring of the image processing system, the precise alignment of the optical fiber during the fusion process can be ensured.

[0021] In addition, the present invention also integrates an ultraviolet glue curing system. By means of wrapping with a glass capillary and fixing with ultraviolet curing glue, the fusion point is effectively protected, and the mechanical strength and stability of the connection are improved. The vertical arrangement design of the graphene electrode rod ensures the uniformity of discharge and the fusion quality.

[0022] Finally, the present invention effectively isolates the interference of the external environment through the setting of a wind shield. Combined with a complete fusion strength test process, it provides a reliable guarantee for the high-quality fusion of the hollow anti-resonant optical fiber. The organic combination of these innovative designs fundamentally solves the technical problems in the connection process of the hollow anti-resonant optical fiber and lays a solid foundation for its popularization in practical applications. Brief Description of the Drawings

[0023] The present invention will be further described below in conjunction with the drawings and embodiments. In the drawings:

[0024] Figure 1 is a schematic diagram of the present invention;

[0025] Figure 2 is a schematic diagram of the optical fiber fixture of the present invention;

[0026] Figure 3 is Figure 2 a partial enlarged view of Detailed Description of the Preferred Embodiments

[0027] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0028] Embodiment 1

[0029] In the context of the rapid development of contemporary optical communication technologies, hollow-core optical fibers are gradually becoming an important technical route for high-end optical applications due to their unique transmission performance. However, the precise fusion splicing of hollow-core optical fibers has always been a key technical bottleneck restricting their wide application. Therefore, the present invention proposes an innovative discharge fusion splicing platform aimed at fundamentally solving the problems of precision and stability in the fusion splicing of hollow-core optical fibers.

[0030] As Figures 1-3 shown, the overall architecture of the present invention can be summarized into six core subsystems, namely, the optical fiber fixture, the discharge fusion splicing unit, the multi-axis motion platform, the wind shield 8 and the image processing system, the presser foot 2 limiting mechanism, and the control and communication system. Through modular design, these subsystems are not only convenient for precision machining and assembly, but also achieve efficient cooperation among various functional modules.

[0031] Among these systems, the optical fiber fixture is undoubtedly the most innovative core of the present invention. Its design fully considers the special structural characteristics of hollow-core optical fibers and adopts a precise positioning groove design. The optical fiber fixture includes a left optical fiber fixture 4 and a right optical fiber fixture 3, and the left optical fiber fixture 4 and the right optical fiber fixture 3 have the same structure. Taking the right optical fiber fixture 3 as an example, the right optical fiber fixture 3 includes a bottom plate, a U-shaped positioning groove and a V-shaped positioning groove arranged on the bottom plate, and the U-shaped positioning groove and the V-shaped positioning groove constitute the key mechanism for precise optical fiber positioning.

[0032] The U-shaped groove ensures the horizontal and stable placement of the optical fiber through a width that precisely matches the diameter of the optical fiber; while the V-shaped groove 7 provides precise radial positioning and angle control through its special geometric design. The included angle of the V-shaped groove 7 is strictly controlled between 60° and 120°, its depth is designed to be 0.5 - 1.5 times the outer diameter of the optical fiber, and the roughness of the groove wall is controlled below 10 nanometers. As an auxiliary, the bottom plate is also equipped with a guide seat and a Y-shaped guide hole, further improving the accuracy of optical fiber positioning and effectively reducing the errors that may be introduced by manual operation.

[0033] The discharge fusion splicing unit uses two symmetrically arranged graphene electrode rods 6, which have more excellent electrical conductivity, thermal stability, and discharge uniformity compared with traditional metal electrodes. The geometric arrangement of the electrode rods is carefully designed and arranged perpendicular to the optical fiber positioning groove, which not only ensures the symmetry of the discharge area but also minimizes the thermal influence area to the greatest extent.

[0034] The multi-axis motion platform can achieve precise alignment of the optical fiber. The linear displacement module can achieve sub-micron axial displacement, and the rotation module can achieve angular adjustment accurate to 0.01°. This high-precision motion control enables the entire optical fiber alignment process to be completed within 1 - 2 seconds and can automatically adjust the position of the optical fiber according to the image information transmitted in real time by the image processing system.

[0035] The wind shield 8 and the image processing system further enhance the precision of the welding platform. The wind shield 8 not only has a protective function but is also the key to precise alignment. The high-precision camera built into it can capture the fiber end face in real time, and identify the fiber core through advanced image processing algorithms, achieving sub-pixel positioning accuracy.

[0036] The innovative design of the limit mechanism of the pressure foot 2 cleverly solves the technical problem of fiber positioning. Through precise cooperation with the U-shaped and V-shaped positioning grooves, the pressure foot 2 can achieve precise limiting without loading the fiber, fundamentally ensuring the stability of the welding process.

[0037] The control and communication system of the present invention uses an industrial-grade embedded controller to achieve real-time recording of parameters, bus communication, and fault self-diagnosis, providing a strong guarantee for the high reliability of the entire welding platform.

[0038] Embodiment 2:

[0039] The discharge welding platform in this embodiment designs an innovative and precise welding process flow for the particularity of hollow-core fibers. As a new type of fiber transmission medium, the core feature of hollow-core fibers is that the central region of the fiber is a cavity structure. Compared with traditional solid fibers, the precision requirements for the welding process are more stringent.

[0040] Preparation stage: First, the operator needs to perform strict pre-treatment on the hollow-core fibers to be welded. The pre-treatment process includes: fiber surface cleaning, precise stripping of the outer protective layer of the fiber core, end face flattening and detection. Optical-grade isopropyl alcohol and high-purity dust-free cloth are used for surface cleaning to ensure that there are no impurities on the fiber end face. When stripping the protective layer, a precision fiber stripper is used, and the stripping length error is controlled within ±0.1 mm. A special fiber cutting knife is used for end face flattening, and the cutting angle error is controlled within 0.5° to ensure the flatness of the welding interface.

[0041] Fiber positioning stage: Open the wind shield 8 and the fiber fixture, and precisely place the two hollow-core fibers to be welded in the fiber fixture. The U-shaped and V-shaped positioning grooves of the fiber fixture play a key role. The width of the U-shaped groove is precisely matched with the fiber diameter to ensure that the fiber is placed horizontally; the design of the V-shaped groove 7 (the included angle is 60° - 120°, and the depth is 0.5 - 1.5 times the outer diameter of the fiber) can achieve precise positioning and angle control of the fiber.

[0042] The Y-shaped guiding holes on the guiding seat further assist the precise placement of the fiber. The Y-shaped design can guide the fiber to slide into the first fiber positioning groove naturally and precisely, reducing manual operation errors. The position of each fiber fixture is adjustable, providing a flexible adaptation space for different specifications of fibers.

[0043] Alignment and Precision Regulation Stage: After closing the wind shield 8 and the optical fiber fixture, the microscope image processing system 1 starts to work. The system uses a high-precision camera to capture the image of the optical fiber end face in real time, and identifies the position of the optical fiber core through image processing algorithms. The multi-axis motion platform plays a key role. The platform includes at least one linear displacement module that moves along the optical fiber axis and a circumferential rotation module. The accuracy of the linear displacement module can reach the sub-micron level, and it can perform fine adjustment along the optical fiber axis direction; the rotation module can achieve an angular adjustment with an accuracy of 0.01°.

[0044] The image processing system transmits the alignment error of the optical fiber core to the multi-axis motion platform in real time, and the platform automatically adjusts the position of the optical fiber according to the error signal. The alignment process is divided into two stages: coarse adjustment and fine adjustment. In the coarse adjustment stage, the optical fiber spacing is quickly reduced, and in the fine adjustment stage, sub-micron level precise alignment is performed. The entire alignment process can be completed within 1 - 2 seconds.

[0045] Fusion Discharge Stage: When the core alignment is completed, the graphene electrode rod 6 starts to generate arc discharge. The graphene electrode has excellent electrical conductivity and thermal stability, and can provide a more stable and uniform discharge environment.

[0046] The discharge parameters can be precisely regulated, including:

[0047] Discharge current: Usually controlled between 0.5A and 1.5A. Discharge time: The discharge time is between 6 seconds and 12 seconds. Discharge energy: Precisely controlled to avoid damage to the optical fiber structure caused by overheating. During the discharge process, the pressure foot 2 always maintains precise limit on the optical fiber to ensure the stability of the fusion process.

[0048] Example 3:

[0049] Strength Testing Stage: After the fusion is completed, the platform will automatically perform strict strength testing. The multi-axis motion platform generates small displacements (displacement range 0.1 - 0.5mm) to the left and right respectively to simulate the tensile stress under actual use conditions. The testing system monitors the following parameters in real time:

[0050] Tensile displacement - force curve, maximum tensile strength. If the hollow optical fiber is not broken and the tensile strength reaches the preset threshold (usually more than 80% of the original optical fiber strength), the strength of the fusion point is determined to be qualified. Unqualified fusion samples will be automatically marked and can be traced back to the specific fusion parameters.

[0051] UV Glue Curing Treatment: To enhance the mechanical strength and optical performance of the fusion point, a precise UV glue curing treatment is introduced. The treatment process is as follows:

[0052] Use a high-precision glass capillary to wrap the fusion point. The inner diameter tolerance of the capillary is controlled within 10 μm to ensure uniform coverage of the fusion area. Inject a special ultraviolet curable glue. This glue has the following key properties: rapid curing (completed within 30 seconds), low shrinkage stress (<0.5%), high transparency (transmittance >99%), good adhesion, and wide temperature adaptability (-40°C to +85°C). Place it in the ultraviolet glue curing system 5. The key parameters of the system include: ultraviolet light wavelength: 365 nm, light intensity: 10 - 15 mW / cm², curing time: 30 - 60 seconds, temperature control: constant temperature of 25 ± 2°C (the ultraviolet curing system uses a cold light source, and the temperature can be controlled at 25 ± 2 degrees. Generally, a hot light source is used in the industry currently, and the temperature is relatively high. This has a significant improvement in the safety of operators and the stability of equipment). After curing, the fusion point not only has a significant improvement in mechanical strength but also further optimizes its optical performance, meeting the stringent requirements of high-precision optical communication systems.

[0053] It should be understood that those of ordinary skill in the art can make improvements or transformations according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A hollow-core optical fiber discharge fusion platform for active optical cables, characterized in that: The invention comprises a discharge welding platform, wherein the discharge welding platform comprises a fixed welding unit and an openable and closable windshield, the arrangement positions of the welding unit and the windshield correspond to each other, optical fiber clamps with adjustable spatial positions are arranged on both sides of the welding unit, each optical fiber clamp comprises a base plate and an openable and closable cover plate connected to the base plate, a first optical fiber positioning groove is arranged on the base plate, a boss is arranged on the end surface of the base plate facing the welding unit, a second optical fiber positioning groove is arranged on the boss, the first optical fiber positioning groove and the second optical fiber positioning groove are arranged coaxially, optical fiber avoidance holes are arranged on both sides of the windshield, an image processing system and a presser foot are arranged in the windshield, the presser foot is located between the second optical fiber positioning grooves, the second optical fiber positioning groove is located between the first optical fiber positioning grooves, and the presser foot can cooperate with the first optical fiber positioning groove and the second optical fiber positioning groove to complete the limitation of the optical fiber without loading the optical fiber.

2. The hollow-core optical fiber discharge fusion splicing platform for active optical cables according to claim 1, characterized in that: The first optical fiber positioning groove is a U-shaped groove, and the second optical fiber positioning groove is a V-shaped groove.

3. The hollow-core optical fiber discharge fusion splicing platform for active optical cables according to claim 2, characterized in that: The width of the U-groove corresponds to the diameter of the optical fiber, and the angle of the V-groove is , 60°≤ ≤120°, the depth of the V-groove is h, 0.5d≤h≤1.5d, d is the outer diameter of the optical fiber, and the roughness of the two walls of the V-groove is Less than 10nm.

4. The hollow-core optical fiber discharge fusion splicing platform for active optical cables according to claim 3, characterized in that: The bottom plate is provided with a guide seat for guiding the optical fiber to fall into the first optical fiber positioning groove, and the guide seat is provided with a guide hole.

5. The hollow-core optical fiber discharge fusion splicing platform for active optical cables according to claim 4, characterized in that: The cross-sectional shape of the guide hole is Y-shaped.

6. The hollow-core optical fiber discharge fusion splicing platform for active optical cables according to claim 1, characterized in that: Two multi-axis motion platforms are symmetrically arranged on the discharge welding platform, the moving end of the multi-axis motion platform is connected to the optical fiber clamp, and the multi-axis motion platform is communicatively connected to the image processing system.

7. The hollow-core optical fiber discharge fusion splicing platform for active optical cables according to claim 6, characterized in that: The multi-axis motion platform comprises at least one first linear displacement module which can be displaced along the axial direction of the optical fiber and at least one rotation module which can be rotated along the circumferential direction of the optical fiber.

8. The hollow-core optical fiber discharge fusion splicing platform for active optical cables according to claim 1, characterized in that: The fusion unit includes two symmetrically arranged graphene electrode rods, and the arrangement direction of the two graphene electrode rods is perpendicular to the arrangement direction of the first optical fiber positioning groove.

9. The hollow-core optical fiber discharge fusion splicing platform for active optical cables according to claim 1, characterized in that: Also includes UV glue curing system.

10. A method for fusing hollow core optical fibers using the discharge fusion splicing platform as claimed in any one of claims 1 to 9, characterized in that: Open the wind shield and fiber clamp; place two hollow-core optical fibers to be fused in the fiber clamp respectively, and keep the two hollow-core optical fiber ports between the V-groove of the fiber clamp and the graphene electrode rod; close the wind shield and fiber clamp, the microscope image processing system collects the alignment angle of the two optical fibers and controls the multi-axis motion platform to slowly move the two optical fibers closer, and rotate the fiber clamp to align the cores of the two hollow-core optical fibers; generate arc discharge through the graphene electrode rod for welding; after opening the wind shield, the multi-axis motion platform automatically moves to the left and right to test the strength of the welding point. If the hollow-core optical fiber is not broken, it means that the strength of the welding point meets the requirements; use a glass capillary to wrap and fix the fused hollow-core optical fiber welding point, inject UV curing glue and put it into the UV glue curing system for fixation.

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