Hollow optical fiber and method of manufacturing a preform thereof

Abstract

The application discloses a kind of hollow optical fiber and its preform manufacturing method, the hollow optical fiber includes outer cladding, connecting piece and anti-resonance unit;Connecting piece and anti-resonance unit form hollow core by enclosing;Both also form first, second cladding cavity with outer cladding together enclosing;Anti-resonance unit is evenly distributed around core, and only with two side connecting piece direct connection, not contact with outer cladding.Preform manufacturing method is to prepare the preform of anti-resonance unit and connecting piece first, then it is assembled, fixed into core assembly by using a kind of axial uniform gear type inner support, removes support after welding and forms integrated core structure, finally, additional cladding and draw into optical fiber.The application is through the precise positioning process of unique structural design and gear type inner support, effectively ensure the uniformity of anti-resonance unit distribution, avoid welding deformation, significantly improve the transmission performance and preparation yield of optical fiber, while simplifying process flow.

Description

Technical Field

[0001] This invention relates to the field of optical fiber communication transmission technology, and in particular to a hollow optical fiber and a method for manufacturing its preform. Background Technology

[0002] Anti-resonant hollow fiber (HC-ARF) uses the anti-resonant reflection effect of anti-resonant units to confine optical signals within the hollow fiber core for transmission, fundamentally reducing the interaction between light and solid materials. It effectively solves problems such as low damage threshold and strong nonlinear effects of traditional silica optical fiber, and has become a core technology direction in the fields of high-power laser transmission and long-distance high-bandwidth communication.

[0003] In the performance system of HC-ARF, the uniformity of the distribution of anti-resonant units is the key factor that determines its optical transmission loss. The anti-resonant units need to be distributed symmetrically and at equal intervals around the hollow fiber core in order to form a uniform anti-resonant mode field. If the spacing deviation exceeds 1%, it will lead to light leakage and cause additional transmission loss. However, the arrangement of anti-resonant units in existing HC-ARF systems relies on manual positioning and welding during the preform fabrication stage. Due to the limited precision of manual adjustment, the distribution deviation of anti-resonant units around the fiber core generally exceeds 1%. Furthermore, in existing processes, the connection between the anti-resonant units and the cladding tube is achieved through direct high-temperature welding, which can easily lead to the collapse and bending of the anti-resonant units due to random factors during the welding process. Simultaneously, pressure control and the drawing process further exacerbate the structural deformation of the anti-resonant units. Especially with large aperture (fiber core diameter > 50 μm) and multiple anti-resonant units (number > 7), the yield rate can drop below 30%, significantly increasing the manufacturing cost. Therefore, the core technical challenge of current antiresonant hollow fiber lies in the difficulty of controlling the uniformity of antiresonant unit distribution, which directly leads to high transmission loss and low yield, failing to meet the practical needs of high-power laser transmission, long-distance communication, and other fields. Thus, developing a technology for antiresonant hollow fiber preforms that achieves uniform distribution of antiresonant units and significantly improves fabrication stability has become a crucial area requiring breakthroughs in this field.

[0004] CN 113905991 A describes the arrangement of the preformed anti-resonant element, the machining of the cladding tube to form an inner hole, and the insertion of a positioning template into the inner hole of the cladding tube. The positioning template has a retaining element for positioning the preformed anti-resonant element at the specified position. Because the cladding tube has curvature and ellipticity, for this assembly method, its inner wall cannot form a full circumferential tight fit with the positioning unit and the outer wall of the anti-resonant unit; an assembly allowance is still required, otherwise the glass tube will break. This will cause the glass tube to move during welding and bonding, leading to orientation deviation or even detachment of the anti-resonant unit.

[0005] CN 119750900 A controls the fixing and distribution uniformity of the anti-resonance units using a conical mold. However, the azimuth alignment of the molds at both ends of the preform still relies on manual inspection and determination. This easily leads to torsion of the anti-resonance units within the tube. Furthermore, since there is no mold support inside the outer tube, the distribution of the welded anti-resonance units to the outer tube is not always uniform. Additionally, because the outer tube typically has a certain ellipticity, its inner wall cannot form a full circumferential tight fit with the outer wall of the mold and the outer wall of the anti-resonance units. Excessive interference at the short axis can cause deformation or even breakage of the mold / anti-resonance unit under pressure, while gaps will form at the long axis. This non-uniform gap causes radial movement of the anti-resonance units during preform processing (such as handling and welding), directly resulting in uneven distribution of the anti-resonance units.

[0006] CN 119937083 A describes a method for adjusting the azimuth angle of nested structural units by real-time pressure regulation of the capillary tubes in the filling layer during optical fiber drawing. This facilitates online control of the azimuth angle deviation of the nested structural units, ensuring precise positioning of each unit in the inner cladding. However, real-time positioning and adjustment requires online observation, resulting in a complex structure and poor stability. Furthermore, the need for individual air pressure control for each anti-resonant unit reduces the structural uniformity of the optical fiber during the drawing process. Summary of the Invention

[0007] In view of this, the present invention addresses the shortcomings of existing technologies, and its main objective is to provide a method for manufacturing hollow-core optical fibers and their preforms. This method employs an offline precision assembly process using gear-type internal support components, ensuring that the spacing deviation between units can be controlled within 2μm. Addressing the process pain point of "easily deformed and collapsed anti-resonant units during welding," the present invention innovatively introduces independent "connectors" into the optical fiber structure. This allows the anti-resonant units to be fixed only by connectors on both sides, achieving an indirect and isolated connection with the outer cladding, thereby isolating the direct impact of welding thermal stress. Addressing the challenges of "complex processes requiring online observation and manual alignment," the present invention utilizes an offline process where an integrated core assembly is welded and then combined with the cladding, completely eliminating the need for online adjustments and simplifying the process flow. This significantly improves the yield rate and substantially reduces transmission loss.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: A hollow optical fiber, comprising: Outer cladding; Multiple connectors; Multiple anti-resonant units; The connector and the anti-resonance unit together form a hollow fiber core; A first cladding cavity is formed by an anti-resonant unit, two connectors directly connected to it, and the outer cladding layer. The first cladding cavity is located outside the anti-resonant unit. A second cladding cavity is formed by a connector and the outer cladding layer, and the second cladding cavity is located outside the connector; The anti-resonance units are evenly distributed around the hollow fiber core and are directly connected only to the connectors on both sides, without contacting the outer cladding.

[0009] As a preferred embodiment: the anti-resonance unit is a single-layer tube or a single-layer half-tube, or multiple nested tubes or nested half-tubes with different radii, and all tubes have circular cross-sections; the outermost tube of the anti-resonance unit has an outer diameter of 8-50μm, and the wall thickness of each tube layer is 0.1-3μm.

[0010] As a preferred embodiment: the connector is directly connected to the outer cladding and has at least two connection points, and the connector wall thickness is 0.1-20μm.

[0011] As a preferred embodiment: the length of the first cladding cavity is 3-30 μm and the aspect ratio is 1-10; the length of the second cladding cavity is 5-50 μm and the aspect ratio is 1-10.

[0012] As a preferred embodiment, the leakage loss between the anti-resonant units is less than 1 dB / km.

[0013] As a preferred embodiment, the number of anti-resonance units is 4-20.

[0014] As a preferred embodiment, the number of connectors is the same as that of the anti-resonance unit.

[0015] As a preferred embodiment, the spacing deviation between the anti-resonant units is less than 2 μm.

[0016] A method for manufacturing a preform for the hollow optical fiber includes the following steps: S1. Prepare anti-resonance unit preforms and connector preforms. The anti-resonance unit preform is an axially uniform circular tube or semi-circular tube, or a nested structure formed by a combination of circular tubes and / or semi-circular tubes. The connector preform is an axially uniform flat plate, arc, groove or column structure, and both are made of quartz glass or doped quartz glass. S2. The anti-resonance unit prefabricated component and the connector prefabricated component are assembled and fixed in corresponding positions using the inner support component to form a core assembly. The inner support component is an axially uniform gear-shaped structure, and its cross-section has at least two contact points with the cross-section of each anti-resonance unit prefabricated component, and is provided with a snap-fit ​​structure for fixing the connector prefabricated component. S3. Weld the core assembly into a single core structure, and then remove the inner support components; S4. The integrated core structure is covered with a cladding material and stretched to form a preform. The cladding material is quartz glass or doped quartz glass. S5. Draw the preform into a hollow optical fiber.

[0017] As a preferred option, the inner support component is made of copper, aluminum alloy, stainless steel, or quartz glass.

[0018] Compared with the prior art, the present invention has significant advantages and beneficial effects. Specifically, as can be seen from the above technical solution, First, offline precision assembly using gear-shaped internal supports can stably control the circumferential spacing deviation of the anti-resonant units within 2μm, fundamentally solving the accuracy bottleneck of manual positioning and significantly reducing optical leakage loss. Second, since the anti-resonant units do not directly contact the outer cladding in the final structure, the deformation problem caused by welding thermal stress is greatly alleviated, improving the fabrication yield. Finally, the entire process eliminates the need for complex online observation and real-time adjustment systems, solving the uniformity problem in one step through offline assembly, simplifying the process flow, reducing equipment complexity and manufacturing costs, and further improving the single-mode performance of the optical fiber through optimized cladding cavity design.

[0019] To more clearly illustrate the structural features and effects of the present invention, a detailed description is provided below in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the radial cross-section of the hollow-core optical fiber in Embodiment 1 of the present invention; Figure 2 This is a schematic cross-sectional view of the gear-type internal support member in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the end face of the core assembly in Embodiment 1 of the present invention; Figure 4 This is a schematic cross-sectional view of the integrated core structure of Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the radial cross-section of the hollow optical fiber in Embodiment 2 of the present invention; Figure 6 This is a schematic diagram of the end face of the core assembly in Embodiment 2 of the present invention; Figure 7 This is a schematic diagram of the radial cross-section of the hollow optical fiber in Embodiment 3 of the present invention; Figure 8 This is a schematic diagram of the end face of the core assembly in Embodiment 3 of the present invention;

[0021] Figure 9 The figure shows the simulation results of the effect of the offset of the anti-resonant unit in hollow fiber on leakage loss.

[0022] Explanation of reference numerals in the attached diagram: 101. Outer cladding layer; 102. Connector; 103. Anti-resonance unit; 104. Hollow fiber core; 105. First cladding cavity; 106. Second cladding cavity; 107. Inner support component. Detailed Implementation

[0023] The present invention is as follows Figures 1 to 9 As shown, a hollow-core optical fiber and its preform manufacturing method are disclosed. This invention aims to solve a series of problems in existing anti-resonant hollow-core optical fibers (HC-ARF), such as poor uniformity of anti-resonant unit distribution, high transmission loss, low yield, and complex processes due to low manual positioning accuracy of anti-resonant units and easy deformation during welding. Its core solution comprises two complementary parts: a specific optical fiber structure design and an offline assembly manufacturing method for preforms based on gear-type internal support components.

[0024] Example 1: 532nm visible light multimode transmission hollow-core optical fiber and its fabrication method; This embodiment specifically implements a hollow-core optical fiber suitable for 532nm wavelength visible light transmission and its manufacturing process.

[0025] First, regarding the structure of hollow-core optical fiber products: The specific structure of the hollow optical fiber in this embodiment is shown in the attached figure. Figure 1 As shown, the optical fiber includes an outer cladding 101. The outer cladding 101 is a high-purity quartz glass tube with an OH⁻ content of less than 1 ppm, and the final outer diameter of the fiber is 400 μm. The optical fiber includes multiple anti-resonance units 103 and multiple connectors 102. Specifically, there are 17 anti-resonance units 103 (the number of anti-resonance units 103 can be "4-20"). These 17 anti-resonance units 103 are circumferentially and uniformly arranged around the hollow fiber core 104. In this embodiment, each anti-resonance unit 103 is a single-layer circular tube structure, and all tubes have a circular cross-section. The outermost tube of the anti-resonance unit 103 has an outer diameter of 14 μm and a wall thickness of 0.47 μm (outermost tube outer diameter 8-50 μm, wall thickness of each layer 0.1-3 μm).

[0026] The number of connectors 102 is the same as that of the anti-resonant units 103; specifically, there are also 17 connectors 102, the same as the number of anti-resonant units 103. In this embodiment, the connectors 102 are designed as arc-shaped structures with a wall thickness of approximately 1.5 μm (the wall thickness of connector 102 is 0.1-20 μm). Each connector 102 is directly connected to the anti-resonant units 103 on the left and right sides, and its arc-shaped outer surface is directly connected to the outer cladding 101, forming two stable connection points.

[0027] A hollow fiber core 104 with an inner diameter of 72 μm is formed by the inner surface of the connector 102 and the inner wall of the anti-resonance unit 103, serving as a transmission channel for optical signals. Two unique cladding cavity structures are formed by the connector 102, the anti-resonance unit 103, and the outer cladding layer 101. The first cladding cavity 105 is located outside the anti-resonance unit 103 and is formed by one anti-resonance unit 103, two connectors 102 directly adjacent to this unit, and the outer cladding layer 101. In this embodiment, the first cladding cavity 105 has a length of 3-30 μm and an aspect ratio of 1-10; specifically, the first cladding cavity 105 has a length of approximately 5 μm, a width of approximately 4.2 μm, and an aspect ratio of approximately 1.2. The second cladding cavity 106 is located outside the connector 102 and is formed by one connector 102 and the outer cladding layer 101. The second cladding cavity 106 (5-50 μm in length, aspect ratio 1-10), specifically, has a length of approximately 12.5 μm, a width of approximately 6 μm, and an aspect ratio of approximately 2.1. Testing of the fabricated optical fiber revealed a spacing deviation of only 0.5 μm between adjacent anti-resonant units 103 (the spacing deviation between adjacent anti-resonant units 103 is designed to be less than 2 μm), directly demonstrating the superior effect of this invention in controlling distribution uniformity. At a working wavelength of 532 nm, the transmission loss of this optical fiber is 60 dB / km, meeting the application requirements of specific visible light transmission scenarios.

[0028] Secondly, regarding the manufacturing method of the preform for the aforementioned hollow optical fiber: Step S1, Prefabrication: Prefabricated anti-resonance unit prefabricated components are prepared using high-purity quartz glass tubes with an outer diameter of 6mm and an inner diameter of 5mm as raw materials. Through cutting and polishing processes, 17 single-layer circular tube prefabricated components with an axial uniformity deviation of less than 0.05mm are produced. This prefabricated component is an "axially uniform circular tube," and its material is quartz glass. Simultaneously, prefabricated connector components are prepared using quartz glass tubes of the same material with an outer diameter of 7mm. These are cut and polished using a diamond cutter to produce 17 semi-circular connector prefabricated components, each 1.5m in length and with a defect-free surface.

[0029] Step S2, Assemble the core assembly: A specially designed 17-arm gear-shaped structure is used as the inner support 107. This inner support 107 is made of copper, aluminum alloy, stainless steel, or quartz glass. The cross-section of the inner support 107 is gear-shaped, with V-shaped grooves on each arm forming at least two contact points with the outer wall of the anti-resonance unit preform. The inner support 107 also has an additional snap-fit ​​structure. During assembly, first, the 17 anti-resonance unit preforms are embedded into the grooves of the gear-shaped support. Then, the 17 arc-shaped connector preforms are placed between adjacent anti-resonance unit preforms and tightly secured using the snap-fit ​​structure, thereby forming a core assembly with a hollow area and no radial movement of any components (as shown in the attached diagram). Figure 3 (As shown).

[0030] Step S3, fabricating the integrated core structure: Rotate the core assembly as a whole and weld it using an oxyhydrogen flame to fuse all the prefabricated connectors and anti-resonance unit prefabricated components into a seamless, bubble-free, and crack-free whole. Then remove the inner support 107 to obtain the attached figure. Figure 4 The integrated core structure is shown. Step S4, fabrication of the preform: A high-purity quartz glass tube with an initial outer diameter of 52 mm, an inner diameter of 40 mm, and a length of 1.5 m is selected as the cladding material. The integrated core structure is inserted into this cladding tube and stretched at a speed of 6 mm / min in a glass drawing furnace to produce a preform with a diameter of approximately 3.3 mm. Step S5, drawing the hollow fiber: The preform is drawn in a fiber drawing tower to finally obtain the hollow fiber described in this embodiment. The overall yield rate of the process reaches 75%, verifying the significant advantages of this method in improving stability and yield.

[0031] Example 2: 1310nm low-loss jumper hollow fiber and its preparation method; This embodiment specifically implements a low-loss hollow-core optical fiber for patch cords suitable for 1310nm communication wavelengths, the structure of which is shown in the attached figure. Figure 5 As shown.

[0032] The optical fiber has an outer diameter of 240 μm. It contains five anti-resonance units 103, arranged in a three-layer nested circular tube structure, consisting of three tightly nested quartz glass tubes of different radii: outermost, middle, and innermost. The outermost tube has an outer diameter of 34 μm and a wall thickness of 1 μm; the middle tube has an outer diameter of 24 μm and a wall thickness of 1 μm; and the innermost tube has an outer diameter of 8 μm and a wall thickness of 1 μm. There are also five connectors 102, which are flat, 35 μm long, and 9 μm thick.

[0033] The hollow core 104 of this optical fiber has an inner diameter of 33 μm. Its first cladding cavity 105 has a length of 30 μm, a width of 4.5 μm, and an aspect ratio of 6.7; the second cladding cavity 106 has a length of 22 μm, a width of 2.2 μm, and an aspect ratio of 10. Precise testing shows that the spacing deviation of the anti-resonant unit 103 in this optical fiber is 0.2 μm, and the leakage loss at a wavelength of 1310 nm is as low as 0.2 dB / km.

[0034] In step S1, the anti-resonance unit prefabrication is fabricated by welding pre-prepared inner, middle, and outer three-layer quartz glass tubes using an oxyhydrogen flame to create five axially uniform three-layer nested prefabrication structures. The connector prefabrication is machined from a quartz glass plate. In step S2, a five-arm aluminum alloy gear-type inner support 107 (the structure can be found in the attached diagram) is used. Figure 6(Illustrative) Precise assembly and fixation are performed. The subsequent welding (S3), inserting the core structure into the cladding tube with an outer diameter of 36 mm and stretching it to form a preform (S4), and drawing the optical fiber (S5) are consistent with the core method of this invention. The final product yield reaches 80%, and it exhibits excellent single-mode characteristics at 1310 nm (LP11 mode loss up to 300 dB / km).

[0035] Example 3: Hollow-core optical fiber for 1064nm high-power laser transmission and its fabrication method; This embodiment addresses the stringent requirements of 1064nm high-power laser transmission by providing a 6-unit double-layer nested hollow fiber structure, as shown in the attached figure. Figure 7 As shown.

[0036] The optical fiber has an outer diameter of 250 μm. There are six anti-resonant units 103, arranged in a double-layer nested circular tube structure. The outer tube has an outer diameter of 30 μm and a wall thickness of 1 μm, while the inner tube has an outer diameter of 20 μm and a wall thickness of 1 μm. There are six connectors 102, which are arc-shaped and have a wall thickness of 5 μm. The hollow fiber core 104 has an inner diameter of 41 μm. The first cladding cavity 105 has a length of 21 μm and a width of 4.5 μm, with an aspect ratio of 4.6; the second cladding cavity 106 has a length of 22 μm and a width of 9 μm, with an aspect ratio of 2.4. Testing of the finished optical fiber shows that the spacing deviation of the anti-resonant units 103 is 0.5 μm, and the leakage loss at a wavelength of 1064 nm is 0.8 dB / km.

[0037] In step S1, a laser welding machine is used to weld the inner and outer layers of quartz glass tubes to prepare six double-nested anti-resonance unit prefabricated parts and six arc-shaped connector prefabricated parts. Step S2 uses a six-arm aluminum alloy gear-type inner support 107 (the structure can be found in the attached diagram). Figure 8 (Illustrative) High-precision assembly is completed. Step S3 uses laser welding to form an integrated structure. In step S4, the core structure is inserted into a quartz glass cladding tube with an outer diameter of 80mm and stretched to form a preform. The finally drawn optical fiber (S5) can stably transmit 1kW of 1064nm continuous laser for up to 1 hour without significant performance degradation, with a yield rate of 70%.

[0038] Appendix Figure 9This is a simulation result diagram illustrating the impact of angular displacement of the anti-resonant unit in a hollow-core optical fiber on leakage loss. Since angular displacement disrupts the symmetry of the fiber structure, the two polarization states of the fundamental mode are no longer degenerate. The two curves in the diagram represent the losses of the two fundamental mode polarization states under angular displacement. The two directional leads in the diagram correspond to the mode field conditions under ideal anti-resonant unit distribution (0° displacement) and 5° displacement (the anti-resonant unit indicated by the arrow has already deviated angularly, corresponding to a displacement distance of approximately 2μm), respectively. Simulation results show that when there is an angular deviation in the distribution of the anti-resonant unit, the leakage loss of the optical fiber increases significantly, and the polarization-dependent loss (PDL) also increases significantly, intuitively verifying the crucial influence of the uniformity of the anti-resonant unit distribution on the optical fiber transmission performance. This diagram further highlights the technical advantages of this invention, which achieves precise positioning and controls the spacing deviation of the control unit within 2μm through a gear-shaped internal support, thereby ensuring low-loss transmission and improving the overall performance and yield of the optical fiber.

[0039] The design focus of this invention is concentrated on two mutually supporting core levels. At the product structure level, the key is the design of an architecture where "connectors" serve as independent structural elements. This allows the anti-resonance units to be fixed and supported only through connectors on both sides, distinguishing it from traditional schemes that directly connect to the cladding. This, combined with the outer cladding, forms first and second cladding cavities of specific dimensions. This structure is crucial for controlling the optical field and optimizing modal characteristics. At the manufacturing process level, the core innovation lies in proposing and employing an offline assembly scheme using a "gear-shaped internal support." This support, through its gear-shaped cross-section, forms multi-point contact with each anti-resonance unit prefabricated component and uses a snap-fit ​​structure to lock the connector prefabricated component, thus forming a high-precision, stable "core assembly" before welding. This is the technological basis for achieving uniform distribution of anti-resonance units and avoiding welding deformation.

[0040] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A hollow-core optical fiber, characterized in that, include: Outer cladding; Multiple connectors; Multiple anti-resonant units; The connector and the anti-resonance unit together form a hollow fiber core; A first cladding cavity is formed by an anti-resonant unit, two connectors directly connected to it, and the outer cladding layer. The first cladding cavity is located outside the anti-resonant unit. A second cladding cavity is formed by a connector and the outer cladding layer, and the second cladding cavity is located outside the connector; The anti-resonance units are evenly distributed around the hollow fiber core and are directly connected only to the connectors on both sides, without contacting the outer cladding.

2. The hollow-core optical fiber according to claim 1, characterized in that, The anti-resonance unit is a single-layer circular tube or a single-layer semi-circular tube, or multiple nested circular tubes or nested semi-circular tubes with different radii, and all tubes have circular or semi-circular cross-sections; the outermost tube of the anti-resonance unit has an outer diameter of 8-50 μm, and the wall thickness of each tube layer is 0.1-3 μm.

3. The hollow-core optical fiber according to claim 1, characterized in that, The connector is directly connected to the outer cladding and has at least two connection points, and the connector wall thickness is 0.1-20μm.

4. The hollow-core optical fiber according to claim 1, characterized in that, The first cladding cavity has a length of 3-30 μm and an aspect ratio of 1-10; the second cladding cavity has a length of 5-50 μm and an aspect ratio of 1-10.

5. The hollow-core optical fiber according to claim 1, characterized in that, The leakage loss between the anti-resonant units is less than 1 dB / km.

6. The hollow-core optical fiber according to claim 1, characterized in that, The number of anti-resonance units is 4-20.

7. The hollow-core optical fiber according to claim 6, characterized in that, The number of connectors is the same as that of the anti-resonance unit.

8. The hollow-core optical fiber according to claim 1, characterized in that, The spacing deviation between the anti-resonant units is less than 2μm.

9. A method for manufacturing a preform for use in hollow optical fibers as described in any one of claims 1-8, characterized in that, Includes the following steps: S1. Prepare anti-resonance unit preforms and connector preforms. The anti-resonance unit preform is an axially uniform circular tube or semi-circular tube, or a nested structure formed by a combination of circular tubes and / or semi-circular tubes. The connector preform is an axially uniform flat plate, arc, groove or column structure, and both are made of quartz glass or doped quartz glass. S2. The anti-resonance unit prefabricated component and the connector prefabricated component are assembled and fixed in corresponding positions using the inner support component to form a core assembly. The inner support component is an axially uniform gear-shaped structure, and its cross-section has at least two contact points with the cross-section of each anti-resonance unit prefabricated component, and is provided with a snap-fit ​​structure for fixing the connector prefabricated component. S3. Weld the core assembly into a single core structure, and then remove the inner support components; S4. The integrated core structure is covered with a cladding material and stretched to form a preform. The cladding material is quartz glass or doped quartz glass. S5. Draw the preform into a hollow optical fiber.

10. The manufacturing method according to claim 9, characterized in that, The inner support component is made of copper, aluminum alloy, stainless steel, or quartz glass.

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