CN116655231A

CN116655231A - Device and method for preparing hollow optical fiber and hollow optical fiber preform

Info

Publication number: CN116655231A
Application number: CN202310650061.1A
Authority: CN
Inventors: 王璞; 姚静远; 张鑫; 万双琴; 金宇龙
Original assignee: Beijing University of Technology
Current assignee: Beijing University of Technology
Priority date: 2023-06-02
Filing date: 2023-06-02
Publication date: 2023-08-29

Abstract

The invention discloses a device for preparing hollow optical fibers and hollow optical fiber preforms, belonging to the technical field of optics and laser photoelectrons; the device comprises: a laser; a focusing assembly including a focusing mirror; a rotating assembly for axially rotating the optical fiber to be processed; the focusing mirror is used for focusing laser emitted by the laser onto the optical fiber to be processed. The invention makes the capillary have minimal deformation, and is suitable for glass tube with arbitrary wall thickness, and has wide applicability. The dimensions may also be scaled to produce a long preform of uniform geometry to draw a longer optical fiber. The method can realize processing of rectangular, hexagonal or irregular shapes, and can prepare hollow optical fibers with more diversified structures. In addition, the laser welding process reduces the manual operation requirement, reduces pollution, improves the manufacturing speed and precision, and is more automatically produced.

Description

Device and method for preparing hollow optical fiber and hollow optical fiber preform

Technical Field

The invention belongs to the technical field of optics and laser photoelectrons, and particularly relates to a device and a method for preparing hollow optical fibers and hollow optical fiber preforms.

Background

Hollow core optical fibers (HCFs) conduct light in air or in a vacuum core, and have attracted attention from researchers for over a century due to their low nonlinear response, low delay and low dispersion, as compared to solid core optical fibers. Many of the limitations of conventional optical fibers stem from the transmission of light in glass. It is therefore desirable to replace glass with air or vacuum, but the light cannot be efficiently guided in simple tunnels in glass fibers. Instead, the hollow core must be surrounded by a microstructured cladding tube that in some way confines the light to the core. The earliest hollow core fibers were hollow core bandgap fibers (HC-PBGF) with cladding consisting of multiple layers of periodically arranged air holes, whereas the cores generally omitted 7-19 air holes to form "defects". The two-dimensional photonic crystal structure of the HC-PBGF cladding enables the mode to be constrained in the air fiber core for transmission in a form similar to Bragg diffraction, and theoretically, the more the number of cladding layers is, the stronger the mode constraint capability is, and therefore the HC-PBGF meets the condition that the optical fiber is required to be bent in many applications without obviously affecting the optical performance.

The first-occurring kagome fiber in 2002, i.e., hollow-core antiresonant fiber (HC-ARF), guides light with antiresonant effect (anti-resonant reflecting optical waveguide, arow). With the advent of anti-resonant optical fibers with novel light guiding mechanisms, students at home and abroad have been devoted to optimization research on the structure and optical performance of the anti-resonant optical fibers. In recent years, HC-ARF layers with simpler cladding structures (single ring without node negative curvature, without node nested tube, without node conjoined tube) and better optical performance have endless, the loss of which has been reduced to 0.28dB/km over HC-PBGF in 2020, and the light guide band can be further extended from ultraviolet to mid-infrared (by changing the thickness of the quartz wall of the cladding). However, the precise requirements of HC-ARF on the shape and thickness of the quartz wall of the cladding layer make it difficult to actually manufacture.

For example, when the optical fiber is a node-free pipe, the optical fiber consists of an outer sleeve and a hollow cladding, and the cladding pipes with small core diameters are placed on the inner wall of the sleeve at equal intervals without contact. One such type is a nested hollow-core antiresonant fiber, in which one or more smaller diameter capillaries are nested in spaced apart smaller diameter tubes and secured against the inner wall so that the contact points between the tubes of each nested set lie in the same azimuthal or circumferential position of the ferrule. The hollow anti-resonance optical fiber with the embedded tube has important significance in the aspects of providing ultra-low loss, wide bandwidth, single-mode optical transmission and the like. In this configuration, however, the contact between the nested tubes remains straight along the length of the fiber and parallel to the longitudinal central axis of the ferrule, these precise and strict geometries being critical factors in their possessing high performance. The preparation of hollow-core optical fibers having various microstructures is therefore an important factor limiting their wide application.

Conventional optical fiber production typically requires a two-step drawing process to first produce a larger size glass preform by stacking, the preform having a cross-section that is the same as the cross-sectional configuration of the desired optical fiber. And (3) placing the preform in a furnace for heating, and stretching the preform by gravity or the application of a pulling force at the tail end to form a transition product with reduced size and the like. The transition piece is placed in a glass sleeve with larger inner diameter, and is stretched in a furnace for one time, so that the optical fiber with the final required structure can be obtained. In the preparation of bandgap fibers or kagome fibers, since the internal structure is composed of many closely arranged small capillaries, when stacked into a preform inside a ferrule, it is necessary to maintain its position well during the drawing process to obtain a relatively standard microstructured fiber. In order to prevent free movement of the position of the inner capillary, it is necessary to fix it in some way. The manner of fixing the structure of the preform at the end is often insufficient, because the capillary tube can move freely between the two ends during the stretching process of the preform, and a transition product with regular and precise structure cannot be formed, and thus the preparation of the microstructured optical fiber cannot be further realized.

In the conventional preparation process, not only is the process complicated, but also a great deal of manual operations are required, such as the process of stacking, the support tube is required to be placed inside the sleeve to fix the position of the cladding tube, and the process requires very fine and skilled operations, so that mass production is not easy to realize. In order to prevent the internal capillary from shifting as much as possible during the stretching in the furnace, the preform is typically heated at its ends by oxyhydrogen flame to fuse together, which process may have some significant lateral asymmetry. Furthermore, this technique appears to be limited to preforms formed from relatively thick tubes, thereby forming optical fibers with a large wall thickness and a transmission window in the far infrared band. The use of flame fusion glass tubes transfers a large amount of heat to the interior, causing deformation when thinner tubes are used. Thus, this method is not suitable for manufacturing nested optical fiber preforms for low loss optical fibers at shorter wavelengths, particularly near infrared telecommunications wavelengths, which generally require thinner fiber wall thicknesses. Because the ultrafast laser processing technology has a smaller action range, the glass preform can be fused in a small range without causing larger deformation by focusing laser to the action region, the preparation process of the glass preform is simplified to a great extent, the problem that an internal capillary tube is deviated in the drawing process is greatly reduced, and the ultrafast laser processing technology is very important for preparing the node-free optical fiber with a more uniform structure and lower loss.

Disclosure of Invention

The invention aims to provide a system and a method for preparing an optical fiber preform rod, which have simple processes and accurate structures. By utilizing the characteristic of the precise and small working area of the ultrafast laser processing technology, the fusion between capillaries can be realized without considering the limitation of the thickness of the glass tube.

In order to solve the above technical problems, the present invention provides an apparatus for preparing a hollow fiber and a hollow fiber preform, comprising:

a laser;

a focusing assembly including a focusing mirror;

a rotating assembly for axially rotating the optical fiber to be processed;

the focusing mirror is used for focusing laser emitted by the laser onto the optical fiber to be processed.

Preferably, the focusing assembly further comprises a mirror;

the reflecting mirror is used for reflecting laser light emitted by the laser to the focusing mirror.

Preferably, the rotating component is a rotatable clamping groove.

Preferably, the rotating assembly is mounted on a three-dimensional translation stage.

Preferably, the laser is an ultrafast laser.

The invention also provides a preparation method for preparing the hollow optical fiber and the hollow optical fiber preform, which comprises the following steps:

fixing the optical fiber to be processed on the rotating component;

laser is emitted by a laser, and the laser is focused by a focusing mirror;

the focused laser passes through the outer cladding of the optical fiber to be processed, and the focus of the laser is focused to a laser processing area between the outer cladding of the optical fiber to be processed and the anti-resonance inner cladding;

and rotating the optical fiber to be processed through the rotating assembly, and welding and processing the focused laser in a laser processing area on the optical fiber to be processed.

Preferably, before fixing the optical fiber to be processed on the rotating assembly, the method further comprises the steps of:

filler is added to the laser processing region between the outer cladding and the antiresonant inner cladding.

Preferably, the filler is a silica gel.

Compared with the traditional method of using oxyhydrogen flame for fixation, the method has the following advantages:

1) The deformation of the glass tube is reduced, and the preparation of a more accurate optical fiber structure is realized;

2) Fusion between glass tubes with thinner wall thickness can be realized, and the preparation difficulty of thinner-wall thick optical fibers for guiding light in shorter wave bands is reduced;

3) Simplifying the process of preparing the preform and being very likely to be applied to large-scale preparation.

Compared with the traditional oxyhydrogen flame heating fixing mode, the welding technology enables the capillary tube to have minimum deformation, is suitable for glass tubes with any wall thickness, and has wide applicability. The dimensions may also be scaled to produce a long preform of uniform geometry to draw a longer optical fiber. The method can realize processing of rectangular, hexagonal or irregular shapes, and can prepare hollow optical fibers with more diversified structures. In addition, the laser welding process reduces the manual operation requirement, reduces pollution, improves the manufacturing speed and precision, and is more automatically produced.

Drawings

The following describes the embodiments of the present invention in further detail with reference to the accompanying drawings.

FIG. 1 is a schematic view of an apparatus for preparing a preform according to an embodiment of the present invention;

FIG. 2 is a schematic end-face structure of a hollow-core optical fiber according to a first embodiment of the present invention;

FIG. 3 is a schematic end-face structure of a hollow-core optical fiber according to a second embodiment of the present invention;

FIG. 4 is a schematic end-face structure of a hollow-core optical fiber according to a third embodiment of the present invention;

FIG. 5 is a schematic end-face structure of a hollow-core optical fiber according to a fourth embodiment of the present invention;

FIG. 6 is a schematic end-face structure of a hollow-core optical fiber according to a fifth embodiment of the present invention;

fig. 7 is a schematic end-face structure of a hollow-core optical fiber according to a sixth embodiment of the present invention.

In the figure: 1-a laser; a 2-mirror; 3-focusing mirror; 4-rotating the assembly; 5-an optical fiber to be processed; 6-a three-dimensional translation stage; 7-overcladding; 8-antiresonant inner cladding; 9-core region; 10-capillary tube; 11-laser processing area.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may be embodied in many other forms than those herein described, and those skilled in the art will readily appreciate that the present invention may be similarly embodied without departing from the spirit or essential characteristics thereof, and therefore the present invention is not limited to the specific embodiments disclosed below.

The terminology used in the one or more embodiments of the specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the one or more embodiments of the specification. As used in this specification, one or more embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used in one or more embodiments of the present specification refers to and encompasses any or all possible combinations of one or more of the associated listed items.

It should be understood that, although the terms first, second, etc. may be used in one or more embodiments of this specification to describe various information, these information should not be limited by these terms. These terms are only used to distinguish one type of information from another. For example, a first may also be referred to as a second, and similarly, a second may also be referred to as a first, without departing from the scope of one or more embodiments of the present description. The word "if" as used herein may be interpreted as "at … …" or "at … …" or "responsive to a determination", depending on the context.

The invention is described in further detail below with reference to the attached drawing figures:

as shown in fig. 1, the present invention discloses an apparatus for preparing a hollow fiber and a hollow fiber preform, comprising:

a laser 1;

a focusing assembly including a focusing mirror 3;

a rotating assembly 4 for axially rotating the optical fiber 5 to be processed;

wherein, the focusing mirror 3 is used for focusing the laser light emitted by the laser 1 onto the optical fiber 5 to be processed.

Preferably, the focusing assembly further comprises a mirror 2;

the reflecting mirror 2 is used for reflecting the laser light emitted by the laser 1 onto the focusing mirror 3.

Preferably, the rotating assembly 4 is a rotatable clamping groove.

Preferably, the rotating assembly 4 is mounted on a three-dimensional translation stage 6.

Preferably, the laser 1 is an ultrafast laser.

fixing the optical fiber 5 to be processed on the rotating component 4;

laser is emitted by a laser 1, and is focused by a focusing mirror 3;

the focused laser passes through the outer cladding 7 of the optical fiber 5 to be processed, and the focus of the laser is focused to a laser processing area 11 between the outer cladding 7 and the antiresonant inner cladding 8 of the optical fiber 5 to be processed;

the optical fiber 5 to be processed is rotated by the rotating component 4, and the focused laser performs welding processing on the laser processing area 11 on the optical fiber 5 to be processed.

Preferably, before fixing the optical fiber 5 to be processed on the rotating assembly 4, the following steps are also included:

filler is added to the laser processing region 11 between the outer cladding 7 and the antiresonant inner cladding 8 of the optical fiber 5 to be processed.

Preferably, the filler is a silica gel.

The invention discloses a method for preparing an optical fiber and an optical fiber preform by using an ultrafast laser processing technology, in particular to a method for manufacturing a hollow optical fiber, and belongs to the technical field of optics and laser photoelectrons. An optical fiber preform is a tubular element generally comprising a hollow glass sleeve and a glass cladding tube (i.e., an outer cladding 7 and an anti-resonant inner cladding 8), wherein the inner diameter of the sleeve is larger than the outer diameter of the cladding tube so that the cladding tube is disposed inside the sleeve to form the optical fiber preform having a microstructure. The contact area of the outer surface of the cladding tube with the inner surface of the sleeve is parallel to the longitudinal axes of the two tubes, and the sleeve and the cladding tube are fixed in position by focusing the femtosecond laser onto the contact area of the two tubes.

Compared with the traditional preparation method of the optical fiber preform based on oxyhydrogen flame, the preparation method is not only suitable for forming the preform by a relatively thick pipe so as to form an optical fiber with a larger wall thickness to realize a far infrared continuous light guide window, but also suitable for forming the preform by a thinner pipe, and the optical fiber with a smaller wall thickness can realize a light guide passband of a shorter wavelength because the ultrafast laser processing area is small and precise and can not cause larger deformation of the pipe.

The invention can also be directly applied to the preparation of cane with smaller size, thereby realizing the drawing of the optical fiber only by one step, reducing the times of entering the furnace, not only reducing the loss of raw materials, but also further reducing the uncertainty of the structural change of the optical fiber in the furnace. In addition, the quartz glue is utilized in the invention, firstly, the capillaries 10 are pre-fixed, the gap between the capillaries 10 is greatly reduced, the ultrafast laser is convenient for directly carrying out glass welding without accurate optical contact, and the quartz glue can be completely converted into quartz powder at high temperature, so that extra loss is not added to the drawn optical fiber.

The optical fiber preform prepared by the method has the characteristics of uniform structure, difficult deformation, longitudinal stability and no limitation of tube thickness, and provides a simpler realization way for preparing more complex microstructure optical fibers such as nested tube optical fibers and optical fibers conducting lower wave bands.

The method adopts the ultrafast laser processing technology, focuses on the contact area of the two quartz tubes through the lens, scans the ultrafast laser on the quartz tubes to be processed by utilizing the scanning galvanometer or the precise displacement table, and realizes the connection of the quartz tubes through nonlinear absorption effects (thermal effects and non-thermal effects). Provides a new way for preparing hollow optical fibers and hollow optical fiber preforms.

The invention provides a method for manufacturing an optical fiber preform, comprising providing a hollow glass nesting unit with an outer diameter smaller than an inner diameter of an outer tube.

The invention provides a method for manufacturing hollow optical fibers or intermediate transition products for the hollow optical fibers, which comprises the following steps: an optical fiber preform is manufactured according to the above-mentioned method and is drawn to a desired diameter of an optical fiber or a transition product under heat.

The present invention can achieve bonding between capillaries 10 regardless of the glass tube thickness limitations.

The quartz material processed by the invention is not limited to a tubular shape, and rectangular, hexagonal or irregular shape processing can be realized.

The invention has smaller working area, which is in micron order.

The invention can shorten the gap between quartz tubes by placing special filler, can eliminate severe optical contact and greatly reduce processing difficulty.

The used filler is quartz gel, can be converted into quartz powder at high temperature, and other impurities can be completely volatilized, so that the processed quartz optical fiber or quartz optical fiber preform rod is clean and pollution-free.

The preparation of hollow optical fibers and hollow optical fiber preforms of different materials can be satisfied by changing the working wavelength of laser.

In order to better illustrate the technical effects of the present invention, the present invention provides the following specific embodiments to illustrate the above technical flow:

fig. 1 shows a schematic diagram of an apparatus for preparing an optical fiber or a preform according to an embodiment, wherein a laser 1 is an ultrafast laser with adjustable repetition frequency, the operating wavelength is 1064nm, the pulse width is 15ps, the maximum output power is 60W, an output beam is transmitted to a laser working area 11 of an optical fiber 5 to be processed through a reflecting mirror 2 and a focusing mirror 3, scanning processing of the optical fiber 5 to be processed by laser is realized by moving the focusing mirror 3 through a displacement table, the focal length of the focusing mirror 3 is 50mm, the focusing mirror is made of CaF2, and a surface coating film is coated on the surface to bear higher energy density.

The optical fiber 5 to be processed is a quartz tube, and is fixed on the rotating assembly 4, the rotating assembly 4 adopts a rotatable clamping groove, and processing at different angles can be realized by rotating the rotating assembly 4. The rotating assembly 4 is placed on a lower three-dimensional translation table 6 and is used for laser scanning and processing quartz tubes.

The focal point of the laser beam is precisely positioned at the contact area of the optical fiber 5 to be processed and the energy delivered by the laser beam provides localized heating to soften or melt the glass, thereby fusing adjacent structures together, and reducing or avoiding a wide range of distortion due to a wide range of heating. The fusion process may be considered a laser welding process as one or both of the two contacting or nearly contacting surfaces are softened or melted to achieve bonding.

In ultra-short pulse glass welding, the laser operating wavelength used is the glass transparency wavelength. The energy input is established by nonlinear absorption (e.g., multiphoton ionization). If the pulse is long enough, multiphoton ionization may also be accompanied by avalanche ionization (within the same pulse). The addition of avalanche ionization can significantly increase the free electron density, thereby further increasing the absorptivity of the irradiated region. The free electrons generated then transfer their kinetic energy to the glass lattice and heat the glass material. If the next pulse arrives "in advance" and has sufficient overlap with the first pulse (by selecting the proper pulse repetition rate and feed rate) that the glass temperature does not return to room temperature, heat will build up with each incoming pulse near the focal region until quasi-static is reached. The maximum achievable temperature may be in the range of thousands of degrees celsius, in which thermal ionization also occurs. The quartz tube contact portions are fused together by a nonlinear absorption heating process. And selecting different output powers and scanning speeds according to different thicknesses of the quartz tubes so as to finish the connection between the quartz tubes with different wall thicknesses.

The optical fiber 5 to be processed is a rod-shaped microstructure optical fiber, and fig. 2, 3, 4, 5, 6 and 7 show schematic end structures of first, second, third, fourth, fifth and sixth embodiments of the rod-shaped microstructure optical fiber according to the present invention. The structures of the two materials all comprise an outer cladding 7 and an anti-resonance inner cladding 8 which are arranged in sequence from outside to inside; the center of the anti-resonance inner cladding 8 is a fiber core region 9; a plurality of capillaries 10 are provided in the antiresonant inner cladding 8. The anti-resonance inner cladding 8 and the outer cladding region 7 are connected in an ultrafast laser welding mode, and the connection part of the anti-resonance inner cladding 8 and the outer cladding region is a laser working region 11.

The six embodiments given in fig. 2, 3, 4, 5, 6, 7 should be understood as:

1) A rod-like microstructured optical fiber that guides light using the antiresonant principle, severely limits light to a core region having a low refractive index for axial transmission along the core region 9.

2) The number of hollow capillaries 10 arranged in the antiresonant inner cladding 8 may be changed as needed, and the specific structure of the capillaries 10 may be changed as needed.

3) The capillary 10 in the anti-resonance inner cladding 8 has a negative curvature structure, which is beneficial to forming an anti-resonance effect on a specific wavelength, and further limiting the light wave in a fiber core region with a low refractive index.

4) The capillaries 10 in the anti-resonance inner cladding 8 are not contacted with each other, so that light waves are prevented from escaping greatly along the cross section of the optical fiber, and the transmission loss of the optical fiber is reduced.

5) The shape of the capillary 10 in the anti-resonant inner cladding 8 can be varied according to different requirements.

6) The outer cladding 7 and the antiresonant inner cladding 8 may be of any thickness, and the connection may be achieved by laser welding.

7) The laser processing region 11 may be filled with filler prior to processing to reduce processing difficulties.

8) The anti-resonance inner cladding 8 can be made of quartz materials, soft glass materials, polymers and the like, and can be processed by changing the working wavelength of laser.

9) The outer cladding 7 and the antiresonant inner cladding 8 may be a connection between the same materials or may be a connection between different materials.

The invention can be applied to the preparation of hollow optical fibers and hollow optical fiber preforms of other materials, such as soft glass or plastic polymers and the like (transparent at the laser working wavelength) besides the traditional quartz hollow optical fibers.

In the several embodiments provided by the present invention, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and the division of modules, or units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units, modules, or components may be combined or integrated into another apparatus, or some features may be omitted, or not performed.

The units may or may not be physically separate, and the components shown as units may be one physical unit or a plurality of physical units, may be located in one place, or may be distributed in a plurality of different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present invention may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

In particular, according to embodiments of the present disclosure, the processes described above with reference to flowcharts may be implemented as computer software programs. For example, embodiments of the present disclosure include a computer program product comprising a computer program embodied on a computer readable medium, the computer program comprising program code for performing the method shown in the flowcharts. In such embodiments, the computer program may be downloaded and installed from a network via a communication portion, and/or installed from a removable medium. The above-described functions defined in the method of the present invention are performed when the computer program is executed by a Central Processing Unit (CPU). The computer readable medium of the present invention may be a computer readable signal medium or a computer readable storage medium, or any combination of the two. The computer readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above.

The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

The foregoing is merely illustrative of specific embodiments of the present invention, and the scope of the present invention is not limited thereto, but any changes or substitutions within the technical scope of the present invention should be covered by the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. An apparatus for preparing a hollow fiber and a hollow fiber preform, comprising:

a laser (1);

a focusing assembly comprising a focusing mirror (3);

a rotating assembly (4) for axially rotating the optical fiber (5) to be processed;

the focusing mirror (3) is used for focusing laser emitted by the laser (1) onto an optical fiber (5) to be processed.

2. The apparatus for preparing hollow-core optical fibers and hollow-core optical fiber preforms according to claim 1, wherein:

the focusing assembly further comprises a mirror (2);

the reflecting mirror (2) is used for reflecting laser light emitted by the laser (1) onto the focusing mirror (3).

3. The apparatus for preparing hollow-core optical fibers and hollow-core optical fiber preforms according to claim 1, wherein:

the rotating component (4) is a rotatable clamping groove.

4. The apparatus for preparing hollow-core optical fibers and hollow-core optical fiber preforms according to claim 1, wherein:

the rotating assembly (4) is mounted on a three-dimensional translation stage (6).

5. The apparatus for preparing hollow-core optical fibers and hollow-core optical fiber preforms according to claim 1, wherein:

the laser (1) is an ultrafast laser.

6. A method for producing a hollow fiber and a hollow optical fiber preform, the apparatus of the production method being the apparatus for producing a hollow fiber and a hollow optical fiber preform according to any one of claims 1 to 5, comprising the steps of:

fixing an optical fiber (5) to be processed on the rotating component (4);

laser is emitted by a laser (1), and is focused by a focusing mirror (3);

the focused laser passes through an outer cladding (7) of the optical fiber (5) to be processed, and the focus of the laser is focused to a laser processing area (11) between the outer cladding (7) and an anti-resonance inner cladding (8) of the optical fiber (5) to be processed;

and the optical fiber (5) to be processed is rotated by the rotating assembly (4), and the focused laser performs welding processing on a laser processing area (11) on the optical fiber (5) to be processed.

7. The method of producing hollow-core optical fibers and hollow-core optical fiber preforms according to claim 6, characterized in that before fixing the optical fibers (5) to be processed on the rotating assembly (4), it further comprises the steps of:

filler is added in a laser processing region (11) between an outer cladding (7) and an anti-resonant inner cladding (8) of the optical fiber to be processed.

8. The method of preparing hollow-core optical fibers and hollow-core optical fiber preforms of claim 7, wherein:

the filler is quartz gel.