CN111458788A - Superstrong bending-resistant radiation-resistant optical fiber and preparation method thereof - Google Patents

Superstrong bending-resistant radiation-resistant optical fiber and preparation method thereof Download PDF

Info

Publication number
CN111458788A
CN111458788A CN202010247467.1A CN202010247467A CN111458788A CN 111458788 A CN111458788 A CN 111458788A CN 202010247467 A CN202010247467 A CN 202010247467A CN 111458788 A CN111458788 A CN 111458788A
Authority
CN
China
Prior art keywords
optical fiber
resistant
cladding layer
fluorine
inner cladding
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202010247467.1A
Other languages
Chinese (zh)
Other versions
CN111458788B (en
Inventor
骆城
喻煌
彭楚宇
岳静
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fiberhome Fujikura Optic Technology Co ltd
Fiberhome Telecommunication Technologies Co Ltd
Original Assignee
Fiberhome Fujikura Optic Technology Co ltd
Fiberhome Telecommunication Technologies Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fiberhome Fujikura Optic Technology Co ltd, Fiberhome Telecommunication Technologies Co Ltd filed Critical Fiberhome Fujikura Optic Technology Co ltd
Priority to CN202010247467.1A priority Critical patent/CN111458788B/en
Publication of CN111458788A publication Critical patent/CN111458788A/en
Application granted granted Critical
Publication of CN111458788B publication Critical patent/CN111458788B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/02—Optical fibres with cladding with or without a coating
    • G02B6/036—Optical fibres with cladding with or without a coating core or cladding comprising multiple layers
    • G02B6/03616—Optical fibres characterised both by the number of different refractive index layers around the central core segment, i.e. around the innermost high index core layer, and their relative refractive index difference
    • G02B6/03638—Optical fibres characterised both by the number of different refractive index layers around the central core segment, i.e. around the innermost high index core layer, and their relative refractive index difference having 3 layers only
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01—Manufacture of glass fibres or filaments
    • C03B37/012—Manufacture of preforms for drawing fibres or filaments
    • C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01—Manufacture of glass fibres or filaments
    • C03B37/012—Manufacture of preforms for drawing fibres or filaments
    • C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
    • C03B37/018—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD] by glass deposition on a glass substrate, e.g. by inside-, modified-, plasma-, or plasma modified- chemical vapour deposition [ICVD, MCVD, PCVD, PMCVD], i.e. by thin layer coating on the inside or outside of a glass tube or on a glass rod
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2203/00—Fibre product details, e.g. structure, shape
    • C03B2203/32—Eccentric core or cladding

Abstract

The invention provides a superstrong bending-resistant and irradiation-resistant optical fiber, and relates to the technical field of optical fiber production. The optical fiber comprises a core layer (1), an inner cladding layer and an outer cladding layer (4) which are sequentially arranged from inside to outside, wherein the core layer (1), the inner cladding layer and the outer cladding layer (4) are made of quartz, and the inner cladding layer comprises a first fluorine-doped inner cladding layer (2) and a second fluorine-doped inner cladding layer (3) which are sequentially arranged from inside to outside; wherein the core layer (1) is doped with nitrogen element. The invention also provides a preparation method of the superstrong bending-resistant and irradiation-resistant optical fiber, which has the advantages of flexible preparation process and strong adaptability, and the prepared irradiation-resistant optical fiber has greatly reduced additional loss in a bending state and stronger bending resistance.

Description

Superstrong bending-resistant radiation-resistant optical fiber and preparation method thereof
Technical Field
The invention belongs to the technical field of optical fiber production, and particularly relates to a superstrong bending-resistant irradiation-resistant optical fiber and a preparation method thereof.
Background
Optical fibers are increasingly widely applied to radiation-related fields such as aerospace, nuclear industry, military and the like, while conventional fiber core germanium-doped optical fibers are not suitable for being applied to radiation environments because transmission loss is obviously increased in the radiation state and normal communication is affected. Therefore, the development of radiation-resistant optical fibers has become a hot spot of international research.
The radiation-resistant optical fiber is an optical fiber capable of resisting the reduction of transmission performance caused by irradiation of atomic radiation, gamma rays, X rays and ultraviolet rays. The degradation of transmission properties of optical fibers upon irradiation is mainly due to the color centers generated by the dopant species contained in the optical fiber and its own initial atomic defects. On the one hand, the doping substances in the optical fiber, such as colored positive ions, capture part of free electrons irradiated by radiation, and then reduce and form new color centers, and the color centers reduce the transmission capability of the optical fiber. On the other hand, the initial atomic defect ≡ Si-O-Si ≡ bond inherent in the optical fiber is cleaved by a high-energy irradiating ion to form an E' color center and a non-bridged oxygen hollow color center. To avoid the occurrence of color centers in optical fibers under irradiation conditions, it has been conventional to use high purity quartz or to reduce initial atomic defects.
Researchers at home and abroad are always dedicated to solving the technical problem of preparation of the radiation-resistant optical fiber, and the preparation method is mainly based on a pure quartz fiber core and is adapted to different application requirements through improvement of materials and preparation processes. Chinese patent CN101000390A discloses a high-performance radiation-resistant silica fiber and its combination method, wherein the core is made of high-purity silica material, the inner cladding is fluorine doped with pure silica as matrix, and the outer cladding is cerium doped with pure silica as matrix. Chinese patent CN102126825B discloses a method for manufacturing a radiation-resistant high-performance silica fiber, which comprises a fiber core containing hydroxyl and fluorine and taking silica glass material as a substrate, an inner cladding containing fluorine and an outer cladding containing fluorine. Although the optical fibers in these patents have good radiation resistance, the optical fiber waveguide structure thereof does not have bending resistance, and cannot be applied to conditions with small bending radius (such as small-sized optical devices and the like), which severely restricts the practical application of the radiation-resistant optical fibers. Chinese patent CN105676349B discloses a bend insensitive radiation resistant single mode fiber, which has the limitation that the data aperture of the core layer needs to be considered when PCVD is used to prepare fluorine doped depressed layer, resulting in the limitation of the refractive index depth of the depressed cladding layer. Meanwhile, it is a development trend of radiation-resistant optical fibers to improve the bending resistance of radiation-resistant optical fibers.
Therefore, there is a need to develop a super-strong bending-resistant radiation-resistant optical fiber and a method for making the same.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a superstrong bending-resistant irradiation-resistant optical fiber and a preparation method thereof. The core layer of the optical fiber provided by the invention is doped with nitrogen element, and the cladding layer is doped with fluorine element, so that not only can the radiation loss of the optical fiber be effectively reduced, but also the bending resistance of the optical fiber can be effectively improved by fully utilizing the deep fluorine doping technology. The preparation method of the optical fiber provided by the invention gives full play to the characteristic advantages of SPCVD and PCVD processes, adopts SPCVD to prepare the core layer of the irradiation-resistant optical fiber, adopts PCVD to prepare the double inner cladding of the irradiation-resistant optical fiber, adopts OVD to prepare the outer cladding of the irradiation-resistant optical fiber, combines all the layers to form the optical fiber perform, and then prepares the superstrong bending-resistant irradiation-resistant optical fiber through drawing, and the preparation method is simple and efficient.
In order to achieve the above object, a first aspect of the present invention provides a superstrong bending-resistant and irradiation-resistant optical fiber, which includes a core layer, an inner cladding layer and an outer cladding layer sequentially arranged from inside to outside, wherein the core layer, the inner cladding layer and the outer cladding layer are made of quartz, and the inner cladding layer includes a first fluorine-doped inner cladding layer and a second fluorine-doped inner cladding layer sequentially arranged from inside to outside; wherein, nitrogen element is doped in the core layer.
On the basis of the technical scheme, the content of the doped nitrogen element in the core layer is more than 0 and less than or equal to 3.5 percent in percentage by mass.
On the basis of the technical scheme, the content of the fluorine element doped in the first fluorine-doped inner cladding layer is more than 0 and less than or equal to 2.0 percent in percentage by mass; the content of fluorine element doped in the second fluorine-doped inner cladding is 3.0-6.0%.
On the basis of the technical scheme, the outer cladding layer is made of pure quartz.
On the basis of the technical scheme, the refractive index distribution of the core layer is in a step type or gradient gradual change type.
On the basis of the technical scheme, when the refractive index distribution of the core layer is in a step type, the value range of the relative refractive index difference delta n1 between the core layer and the outer cladding layer is more than 0 and less than or equal to delta n1 and less than or equal to 1.0 percent.
On the basis of the technical scheme, when the refractive index distribution of the core layer is in gradient gradual change, the relative refractive index difference delta n1 between the core layer and the outer cladding layermax0.9% -2.1%, and the distribution power function α is 1.8-2.2.
On the basis of the technical scheme, the value range of the relative refractive index difference delta n2 between the first fluorine-doped inner cladding and the outer cladding is-0.3% to delta n2 < 0; the value range of the relative refractive index difference delta n3 between the second fluorine-doped inner cladding and the outer cladding is more than or equal to-1.5 percent and less than or equal to delta n3 and less than 0.
On the basis of the technical scheme, the superstrong bending-resistant radiation-resistant optical fiber is a single-mode optical fiber, a 50-micrometer multimode optical fiber or a 62.5-micrometer multimode optical fiber;
when the superstrong bending-resistant radiation-resistant optical fiber is a single-mode optical fiber, the diameter d1 of the core layer (1) is 8-10 mu m, the diameter d2 of the first fluorine-doped inner cladding layer (2) is 15-21 mu m, the diameter d3 of the second fluorine-doped inner cladding layer (3) is 28-35 mu m, and the diameter d4 of the outer cladding layer (4) is 125 mu m;
when the superstrong bending-resistant radiation-resistant optical fiber is a 50-micrometer multimode optical fiber, the diameter d1 of the core layer (1) is 48-52 micrometers, the diameter d2 of the first fluorine-doped inner cladding layer (2) is 48-56 micrometers, the diameter d3 of the second fluorine-doped inner cladding layer (3) is 56-66 micrometers, and the diameter d4 of the outer cladding layer (4) is 125 micrometers;
when the superstrong bending-resistant radiation-resistant optical fiber is a 62.5-micrometer multimode optical fiber, the diameter d1 of the core layer (1) is 60-65 micrometers, the diameter d2 of the first fluorine-doped inner cladding layer (2) is 60-70 micrometers, the diameter d3 of the second fluorine-doped inner cladding layer (3) is 70-80 micrometers, and the diameter d4 of the outer cladding layer (4) is 125 micrometers.
The second aspect of the present invention provides a method for preparing a super-strong bending-resistant radiation-resistant optical fiber according to the first aspect of the present invention, which comprises the following steps:
preparing a core layer doped with nitrogen element by adopting a reduced pressure plasma chemical vapor deposition method;
preparing a first fluorine-doped inner cladding layer and a second fluorine-doped inner cladding layer by adopting a plasma chemical vapor deposition method;
preparing an outer cladding layer by adopting a tube outside deposition method;
combining the core layer, the first fluorine-doped inner cladding layer, the second fluorine-doped inner cladding layer and the outer cladding layer to manufacture an optical fiber preform;
and drawing the optical fiber preform to obtain the superstrong bending-resistant and irradiation-resistant optical fiber.
Compared with the prior art, the invention has the advantages that:
(1) the core layer of the super-strong bending-resistant radiation-resistant optical fiber is doped with nitrogen elements, and the inner cladding is doped with fluorine elements, so that the optical fiber has radiation resistance in the transmission process; and because the doping of nitrogen element in the core layer does not generate the doping of precursor defect, the radiation loss of the optical fiber with the core layer doped with nitrogen element is far lower than that of the optical fiber with the core layer made of pure quartz, thereby ensuring the radiation resistance of the optical fiber;
(2) the superstrong bending-resistant irradiation-resistant optical fiber provided by the invention can increase the refractive index of the core layer by doping nitrogen elements in the core layer, so that the bending resistance of the optical fiber can be improved by more fully utilizing the deep fluorine doping technology in the preparation of the inner cladding layer.
(3) The preparation method of the superstrong bending-resistant irradiation-resistant optical fiber provided by the invention fully exerts the characteristic advantages of the processes of a reduced pressure plasma chemical vapor deposition (SPCVD) method and a Plasma Chemical Vapor Deposition (PCVD) method, adopts SPCVD to prepare the core layer of the irradiation-resistant optical fiber, adopts PCVD to prepare the double inner cladding layers of the irradiation-resistant optical fiber, adopts OVD to prepare the outer cladding layer of the irradiation-resistant optical fiber, combines all the layers to form an optical fiber preform, and then prepares the superstrong bending-resistant irradiation-resistant optical fiber through drawing.
Drawings
Fig. 1 is a schematic diagram of a structure of a super-strong bending-resistant radiation-resistant optical fiber provided by the invention.
Fig. 2 is a schematic view of a refractive index profile of a super-bending-resistant radiation-resistant optical fiber in embodiment 1 of the present invention.
Fig. 3 is a schematic view of a refractive index profile of a super-strong bending-resistant radiation-resistant optical fiber in embodiment 3 of the present invention.
Fig. 4 is a schematic diagram showing a comparison of refractive index profiles of a conventional radiation-resistant optical fiber (left diagram in fig. 4) and super-bending-resistant radiation-resistant optical fibers of embodiments 1, 3 and 5 (right diagram in fig. 4) of the present invention.
In the figures, the reference numerals have the following meanings:
1-a core layer; 2-a first fluorine-doped inner cladding; 3-a second fluorine-doped inner cladding; 4-an outer cladding;
n1 — refractive index of core layer 1;
n 2-refractive index of the first fluorine doped inner cladding 2;
n 3-refractive index of the second fluorine doped inner cladding 3;
n 4-refractive index of the outer cladding 4 (when the material of the outer cladding 4 is pure quartz (SiO)2) When, also denoted as n0, the refractive index of pure quartz);
d 1-diameter of core layer 1;
d 2-diameter of the first fluorine doped inner cladding 1;
d 3-diameter of the second fluorine doped inner cladding 2.
Detailed Description
In order that the invention may be more readily understood, reference will now be made in detail to the present invention as illustrated in the accompanying drawings and specific examples. It is to be understood that these examples are illustrative only and are not intended to limit the present invention.
In the existing preparation method of the radiation-resistant optical fiber, fluorine element is doped in a core layer, and the data aperture of the core layer needs to be considered when preparing the fluorine-doped sunken cladding layer, so that the refractive index depth of the sunken cladding layer is limited, and the improvement of the bending resistance of the optical fiber is limited. On the premise of not influencing the irradiation resistance of the optical fiber, the inventor finds through a large amount of experimental research that the refractive index of the core layer can be effectively increased by doping nitrogen elements in the core layer, and then the bending resistance of the optical fiber can be effectively improved by fully utilizing the deep fluorine doping technology in the preparation process of the inner cladding layer. And the radiation loss of the optical fiber with the core layer doped with the nitrogen element is far lower than that of the optical fiber with the core layer made of pure quartz, so that the radiation resistance of the optical fiber is guaranteed. In addition, the invention utilizes the combination of SPCVD and PCVD, utilizes SPCVD to prepare the nitrogen-doped core layer, can more fully utilize the deep fluorine-doping technology, and provides a more efficient optical fiber preparation method. The present invention has been made based on the above findings.
As shown in fig. 1, some embodiments of the present invention provide a super bend-resistant radiation-resistant optical fiber. The optical fiber comprises a core layer 1, an inner cladding layer and an outer cladding layer 4 which are sequentially arranged from inside to outside. The core layer 1, the inner cladding layer and the outer cladding layer 4 are all made of quartz (SiO)2). The inner cladding comprises a first fluorine-doped inner cladding 2 and a second fluorine-doped inner cladding 3 which are sequentially arranged from inside to outside. Wherein, the core layer 1 is doped with nitrogen element.
Preferably, the content of the doped nitrogen element in the core layer 1 is greater than 0 and less than or equal to 3.5% by mass percentage.
The core layer of the super-strong bending-resistant irradiation-resistant optical fiber provided by the invention is doped with nitrogen, so that the refractive index of the core layer can be effectively improved on the premise of not influencing the irradiation resistance of the optical fiber, and a foundation is laid for improving the bending resistance of the optical fiber by fully utilizing the deep fluorine doping technology in the subsequent inner cladding preparation process.
Other metal impurities affect the optical transmission loss of the core layer, and therefore, in order to reduce the influence of the other metal impurities on the optical fiber transmission loss, the content of the other metal impurities in the core layer 1 is controlled to be less than 0.1 ppm.
Preferably, the content of the fluorine element doped in the first fluorine-doped inner cladding layer 2 is more than 0 and less than or equal to 2.0 percent in percentage by mass; the content of fluorine element doped in the second fluorine-doped inner cladding 3 is 3.0-6.0%.
Further, the outer cladding layer 4 is made of pure quartz.
Preferably, the refractive index profile of the core layer 1 is stepped or graded.
Referring to fig. 2, when the refractive index profile of the core layer 1 is step-shaped, the relative refractive index difference Δ n1 between the core layer 1 and the outer cladding layer 4 is greater than 0 and less than or equal to Δ n1 and less than or equal to 1.0%.
Referring to fig. 3, when the refractive index profile of the core layer 1 is graded, the relative refractive index difference Δ n1 between the core layer 1 and the outer cladding layer 4max0.9% -2.1%, and the distribution power function α is 1.8-2.2.
Preferably, the relative refractive index difference delta n2 between the first fluorine-doped inner cladding layer 2 and the outer cladding layer 4 is between-0.3% and delta n2 and 0; the value range of the relative refractive index difference delta n3 between the second fluorine-doped inner cladding layer 3 and the outer cladding layer 4 is more than or equal to-1.5 percent and less than delta n3 and less than 0.
In the present invention, the calculation formula of the relative refractive index difference is as follows:
Δ ni ═ [ (ni-n0)/ni ] × 100 (formula I)
In formula (I), ni is the index of refraction of the ith layer and n0 is the index of refraction of the pure silica glass portion (i.e., outer cladding 4), all of which are used as reference indices in the present invention.
For example, when i is 1, n1 is the refractive index of the 1 st layer, i.e., the refractive index of the core layer 1, and the relative refractive index difference Δ n1 between the core layer 1 and the outer cladding layer 4 is [ (n1-n0)/n1] × 100% by weight;
when i is 2, n2 is the refractive index of the 2 nd layer, i.e. the refractive index of the first fluorine-doped inner cladding layer 2, the relative refractive index difference Δ n2 between the first fluorine-doped inner cladding layer 2 and the outer cladding layer 4 is [ (n2-n0)/n2] × 100%;
when i is 3, n3 is the refractive index of the 3 rd layer, i.e. the refractive index of the second fluorine-doped inner cladding layer 3, and the relative refractive index difference Δ n3 between the second fluorine-doped inner cladding layer 3 and the outer cladding layer 4 is [ (n3-n0)/n3] × 100%.
Preferably, the superstrong bending-resistant radiation-resistant optical fiber is a single-mode optical fiber, a 50 μm multimode optical fiber or a 62.5 μm multimode optical fiber.
When the superstrong bending-resistant radiation-resistant optical fiber is a single-mode optical fiber, the diameter d1 of the core layer 1 is 8-10 μm, the diameter d2 of the first fluorine-doped inner cladding layer 2 is 15-21 μm, the diameter d3 of the second fluorine-doped inner cladding layer 3 is 28-35 μm, and the diameter d4 of the outer cladding layer 4 is 125 μm.
When the superstrong bending-resistant radiation-resistant optical fiber is a 50-micrometer multimode optical fiber, the diameter d1 of the core layer 1 is 48-52 micrometers, the diameter d2 of the first fluorine-doped inner cladding layer 2 is 48-56 micrometers, the diameter d3 of the second fluorine-doped inner cladding layer 3 is 56-66 micrometers, and the diameter d4 of the outer cladding layer 4 is 125 micrometers.
When the superstrong bending-resistant radiation-resistant optical fiber is a 62.5-micrometer multimode optical fiber, the diameter d1 of the core layer 1 is 60-65 micrometers, the diameter d2 of the first fluorine-doped inner cladding layer 2 is 60-70 micrometers, the diameter d3 of the second fluorine-doped inner cladding layer 3 is 70-80 micrometers, and the diameter d4 of the outer cladding layer 4 is 125 micrometers.
Other embodiments of the invention provide a method for preparing the ultra-strong bending-resistant radiation-resistant optical fiber. The method comprises the following steps:
s1, preparing the core layer 1 doped with nitrogen element by adopting a reduced pressure plasma chemical vapor deposition method;
s2, preparing a first fluorine-doped inner cladding layer 2 and a second fluorine-doped inner cladding layer 2 by adopting a plasma chemical vapor deposition method;
s3, preparing an outer cladding layer 4 by adopting an outer tube deposition method;
s4, combining the core layer 1, the first fluorine-doped inner cladding layer 2, the second fluorine-doped inner cladding layer 3 and the outer cladding layer 4 to manufacture an optical fiber preform;
and S5, drawing the optical fiber preform to obtain the superstrong bending-resistant and irradiation-resistant optical fiber.
Considering that the depth of the doped F is limited by the PCVD process, after the nitrogen-doped core layer is prepared by adopting SPCVD, the sinking depth can fully play the advantages of the PCVD, namely the depth of the second fluorine-doped inner cladding layer is deeper, and the second fluorine-doped inner cladding layer has better bending resistance.
Therefore, the preparation method of the superstrong bending-resistant irradiation-resistant optical fiber provided by the invention fully exerts the characteristic advantages of the processes of a reduced pressure plasma chemical vapor deposition method (SPCVD) and a plasma chemical vapor deposition method (PCVD), the SPCVD is used for preparing the core layer of the irradiation-resistant optical fiber, the PCVD is used for preparing the double inner cladding layers of the irradiation-resistant optical fiber, the OVD is used for preparing the outer cladding layers of the irradiation-resistant optical fiber, and the preparation method is simple and efficient.
The present invention will be described in detail with reference to specific examples.
Example 1
As shown in fig. 1, the present embodiment provides a super bending-resistant radiation-resistant single-mode optical fiber. The optical fiber comprises a core layer 1, an inner cladding layer and an outer cladding layer 4 which are sequentially arranged from inside to outside. The core layer 1, the inner cladding layer and the outer cladding layer 4 are all made of quartz. The inner cladding comprises a first fluorine-doped inner cladding 2 and a second fluorine-doped inner cladding 3 which are sequentially arranged from inside to outside. The core layer 1 is doped with nitrogen elements, and the content of other metal impurities in the core layer 1 is lower than 0.1 ppm. The outer cladding 4 is made of pure quartz.
As shown in fig. 2, the refractive index profile of the core layer 1 is stepped, and the relative refractive index difference Δ n1 between the core layer 1 and the outer cladding layer 4 is 0.32%. The relative refractive index difference deltan 2 between the first fluorine-doped inner cladding 2 and the outer cladding 4 is-0.03%; the relative refractive index difference Δ n3 between the second fluorine doped inner cladding 3 and the outer cladding 4 is-1.0%. The diameter d1 of the core layer 1 is 90 μm, the diameter d2 of the first fluorine-doped inner cladding layer 2 is 21 μm, the diameter d3 of the second fluorine-doped inner cladding layer 3 is 31.5 μm, and the diameter d4 of the outer cladding layer 4 is 125 μm.
Fig. 4 shows a comparison of refractive index profiles of the conventional radiation-resistant fiber (fig. 4, left) and the super-bending-resistant radiation-resistant fiber provided in this embodiment (fig. 4, right) (the core layer is step-type, i.e., n1 is shown by the solid line in the figure). In fig. 4, the same as the radiation-resistant optical fiber provided in this embodiment, the conventional radiation-resistant optical fiber sequentially includes a core layer 1, a first inner cladding layer 2, a second inner cladding layer 3, and an outer cladding layer 4 from inside to outside, the radius of each layer is the same as that of each layer of the optical fiber provided in this embodiment, and the core layer 1 is made of pure SiO2The first inner cladding layer 2 and the second inner cladding layer 3 are both made of F-doped SiO2The refractive index difference (n1-n2) between the core layer 1 and the first inner cladding layer 2 is the same, and the PCVD fluorine doping limit is n3, except that: the core layer 1 of the conventional radiation-resistant optical fiber is made of pure quartz (pure SiO)2And Δ n1 is 0), and the core layer 1 of the super-bending-resistant radiation-resistant optical fiber provided by this embodiment is made of nitrogen-doped quartz (Δ n1 is 0.32%).
As can be seen from the comparison of the refractive index profiles of the conventional radiation-resistant fiber and the super-bending-resistant radiation-resistant fiber provided in this embodiment in fig. 4, the depth of the second fluorine-doped inner cladding in this embodiment is deeper (i.e., greater from n3 to n 1), i.e., the doping method of the present invention can make full use of the deep fluorine doping technology. Therefore, the superstrong bending-resistant and irradiation-resistant optical fiber provided by the invention can realize better bending resistance than the traditional irradiation-resistant optical fiber.
Example 2
The embodiment provides a preparation method of the super-strong bending-resistant radiation-resistant single-mode fiber of embodiment 1, which includes the following steps:
and S1, preparing the core layer 1 doped with the nitrogen element by adopting a reduced pressure plasma chemical vapor deposition method.
Specifically, SiCl is used4、N2、O2As a raw material, a core rod (i.e., core layer 1) having a relative refractive index difference Δ n1 of 0.32% was prepared by deposition and collapsing.
S2, preparing the first fluorine-doped inner cladding layer 2 and the second fluorine-doped inner cladding layer 3 by adopting a plasma chemical vapor deposition method.
Specifically, a PCVD gas phase doping process is adopted to prepare fluorine-doped inner cladding sleeves (namely a first fluorine-doped inner cladding 2 and a second fluorine-doped inner cladding 3) with relative refractive index differences delta n2 and delta n3 of-0.03 percent and-1.0 percent respectively, and the designed optical rod section is prepared by adjusting the moving speed and the number of deposition passes of a reaction zone.
S3, preparing the outer cladding layer 4 by using an outer tube deposition method.
Specifically, O is introduced2、C2F6Reaction is carried out to remove water, and pure quartz outer cladding with proper proportion is prepared by OVD according to the core cladding ratio.
S4, combining the core layer 1, the first fluorine-doped inner cladding layer 2, the second fluorine-doped inner cladding layer 3 and the outer cladding layer 4 to manufacture the optical fiber prefabricated rod.
And S5, drawing the optical fiber preform to obtain the superstrong bending-resistant and irradiation-resistant optical fiber.
The preparation method of the superstrong bending-resistant irradiation-resistant optical fiber provided by the invention fully exerts the characteristic advantages of the processes of a reduced pressure plasma chemical vapor deposition (SPCVD) method and a Plasma Chemical Vapor Deposition (PCVD) method, the SPCVD method is adopted to prepare the core layer of the irradiation-resistant optical fiber, the PCVD method is adopted to prepare the double inner cladding layers of the irradiation-resistant optical fiber, the OVD method is adopted to prepare the outer cladding layers of the irradiation-resistant optical fiber, and the preparation method is simple and efficient.
Example 3
As shown in fig. 1, the present embodiment provides a super-strong bend-resistant radiation-resistant multimode optical fiber, which is a 50 μm multimode optical fiber. The optical fiber comprises a core layer 1, an inner cladding layer and an outer cladding layer 4 which are sequentially arranged from inside to outside. The core layer 1, the inner cladding layer and the outer cladding layer 4 are all made of quartz. The inner cladding comprises a first fluorine-doped inner cladding 2 and a second fluorine-doped inner cladding 3 which are sequentially arranged from inside to outside. The core layer 1 is doped with nitrogen elements, and the content of other metal impurities in the core layer 1 is lower than 0.1 ppm. The outer cladding 4 is made of pure quartz.
As shown in FIG. 3, the refractive index profile of the core layer 1 is graded, and the relative refractive index difference Δ n1 between the core layer 1 and the outer cladding layer 4max1.01%, and a distribution power function α of 1.98. the relative refractive index difference Deltan 2 between the first fluorine-doped inner cladding 2 and the outer cladding 4 is-0.03%, the relative refractive index difference Deltan 3 between the second fluorine-doped inner cladding 3 and the outer cladding 4 is-1.2%. the diameter d1 of the core layer 1 is 50 μm, the diameter d2 of the first fluorine-doped inner cladding 2 is 52 μm, the diameter d3 of the second fluorine-doped inner cladding 3 is 62.3 μm, and the diameter d4 of the outer cladding 4 is 125 μm.
Fig. 4 shows a comparison of refractive index profiles of the conventional radiation-resistant fiber (fig. 4 left) and the super-bending-resistant radiation-resistant fiber provided in this embodiment (fig. 4 right) (the core layer is step-type, i.e. n1 is shown by the dotted line in the figure). In fig. 4, the same as the radiation-resistant optical fiber provided in this embodiment, the conventional radiation-resistant optical fiber sequentially includes a core layer 1, a first inner cladding layer 2, a second inner cladding layer 3, and an outer cladding layer 4 from inside to outside, the radius of each layer is the same as that of each layer of the optical fiber provided in this embodiment, and the core layer 1, the first inner cladding layer 2, and the second inner cladding layer 3 are all made of F-doped SiO2The refractive index difference (n1-n2) between the core layer 1 and the first inner cladding layer 2 is the same, and the PCVD fluorine doping limit is n3, except that: material of core layer 1 of conventional radiation-resistant optical fiber, the material of core layer 1 is fluorine-doped quartz (Δ n 1)max0 and the distributed power function α is 1.98), and thisThe core layer 1 of the super-strong bending-resistant radiation-resistant optical fiber provided by the embodiment is made of nitrogen-doped quartz (delta n 1)maxIs 1.01%, and the distribution power function α is 1.98).
As can be seen from the comparison of the refractive index profiles of the conventional radiation-resistant fiber and the super-bending-resistant radiation-resistant fiber provided in this embodiment in fig. 4, the depth of the second fluorine-doped inner cladding in this embodiment is deeper (i.e., greater from n3 to n 1), i.e., the doping method of the present invention can make full use of the deep fluorine doping technology. Therefore, the superstrong bending-resistant and irradiation-resistant optical fiber provided by the invention can realize better bending resistance than the traditional irradiation-resistant optical fiber.
Example 4
The embodiment provides a preparation method of the super-strong bending-resistant radiation-resistant multimode optical fiber of embodiment 3, which comprises the following steps:
and S1, preparing the core layer 1 doped with the nitrogen element by adopting a reduced pressure plasma chemical vapor deposition method.
Specifically, SiCl is used4、N2、O2The maximum value of the relative refractive index difference delta n1 is prepared by deposition and melting shrinkage as raw materialmaxA mandrel (i.e., core 1) of 1.01% and a distribution power function α of 1.98.
S2, preparing the first fluorine-doped inner cladding layer 2 and the second fluorine-doped inner cladding layer 3 by adopting a plasma chemical vapor deposition method.
Specifically, a PCVD gas phase doping process is adopted to prepare fluorine-doped inner cladding sleeves (namely a first fluorine-doped inner cladding 2 and a second fluorine-doped inner cladding 3) with relative refractive index differences delta n2 and delta n3 of-0.03 percent and-1.2 percent respectively, and the designed optical rod section is prepared by adjusting the moving speed and the number of deposition passes of a reaction zone.
S3, preparing the outer cladding layer 4 by using an outer tube deposition method.
Specifically, O is introduced2、C2F6Reaction is carried out to remove water, and pure quartz outer cladding with proper proportion is prepared by OVD according to the core cladding ratio.
S4, combining the core layer 1, the first fluorine-doped inner cladding layer 2, the second fluorine-doped inner cladding layer 3 and the outer cladding layer 4 to manufacture the optical fiber prefabricated rod.
And S5, drawing the optical fiber preform to obtain the superstrong bending-resistant and irradiation-resistant optical fiber.
The preparation method of the superstrong bending-resistant irradiation-resistant optical fiber provided by the invention fully exerts the characteristic advantages of the processes of a reduced pressure plasma chemical vapor deposition (SPCVD) method and a Plasma Chemical Vapor Deposition (PCVD) method, the SPCVD method is adopted to prepare the core layer of the irradiation-resistant optical fiber, the PCVD method is adopted to prepare the double inner cladding layers of the irradiation-resistant optical fiber, the OVD method is adopted to prepare the outer cladding layers of the irradiation-resistant optical fiber, and the preparation method is simple and efficient.
Example 5
As shown in fig. 1, the present embodiment provides a super-bend-resistant radiation-resistant multimode optical fiber, which is a 62.5 μm multimode optical fiber. The optical fiber comprises a core layer 1, an inner cladding layer and an outer cladding layer 4 which are sequentially arranged from inside to outside. The core layer 1, the inner cladding layer and the outer cladding layer 4 are all made of quartz. The inner cladding comprises a first fluorine-doped inner cladding 2 and a second fluorine-doped inner cladding 3 which are sequentially arranged from inside to outside. The core layer 1 is doped with nitrogen elements, and the content of other metal impurities in the core layer 1 is lower than 0.1 ppm. The outer cladding 4 is made of pure quartz.
The refractive index distribution of the core layer 1 is graded, and the relative refractive index difference delta n1 between the core layer 1 and the outer cladding layer 4max2.1% and a distributed power function α of 2.2. the relative refractive index difference Δ n2 between the first fluorine-doped inner cladding 2 and the outer cladding 4 is-0.03%, the relative refractive index difference Δ n3 between the second fluorine-doped inner cladding 3 and the outer cladding 4 is-1.2%. the diameter d1 of the core layer 1 is 62 μm, the diameter d2 of the first fluorine-doped inner cladding 2 is 65 μm, the diameter d3 of the second fluorine-doped inner cladding 3 is 75 μm, and the diameter d4 of the outer cladding 4 is 125 μm.
Fig. 4 shows a comparison of refractive index profiles of the conventional radiation-resistant fiber (fig. 4, left) and the super-bending-resistant radiation-resistant fiber provided in this embodiment (fig. 4, right) (the core layer is step-type, i.e., n1 is shown by the solid line in the figure). In fig. 4, the same as the radiation-resistant optical fiber provided in this embodiment, the conventional radiation-resistant optical fiber sequentially includes a core layer 1, a first inner cladding layer 2, a second inner cladding layer 3, and an outer cladding layer 4 from inside to outside, the radius of each layer is the same as that of each layer of the optical fiber provided in this embodiment, and the core layer 1, the first inner cladding layer 2, and the second inner cladding layer 3 are all made of F-doped SiO2The difference between the refractive index of the core layer 1 and the refractive index of the first inner cladding layer 2 (n1-n2), and the fluorine doping limits of the PCVD are all n3, except that: material of core layer 1 of conventional radiation-resistant optical fiber, the material of core layer 1 is fluorine-doped quartz (Δ n 1)max0, the distribution power function α is 2.2), and the core layer 1 of the super-bending-resistant radiation-resistant optical fiber provided by the embodiment is made of nitrogen-doped quartz (Δ n 1)maxIs 2.1% and the distribution power function α is 2.2).
As can be seen from the comparison of the refractive index profiles of the conventional radiation-resistant fiber and the super-bending-resistant radiation-resistant fiber provided in this embodiment in fig. 4, the depth of the second fluorine-doped inner cladding in this embodiment is deeper (i.e., greater from n3 to n 1), i.e., the doping method of the present invention can make full use of the deep fluorine doping technology. Therefore, the superstrong bending-resistant and irradiation-resistant optical fiber provided by the invention can realize better bending resistance than the traditional irradiation-resistant optical fiber.
Example 6
The embodiment provides a preparation method of the super-strong bending-resistant radiation-resistant multimode optical fiber of embodiment 5, which includes the following steps:
and S1, preparing the core layer 1 doped with the nitrogen element by adopting a reduced pressure plasma chemical vapor deposition method.
Specifically, SiCl is used4、N2、O2The maximum value of the relative refractive index difference delta n1 is prepared by deposition and melting shrinkage as raw materialmaxA mandrel (i.e., core 1) of 2.1% and a distribution power function α of 2.2.
S2, preparing the first fluorine-doped inner cladding layer 2 and the second fluorine-doped inner cladding layer 3 by adopting a plasma chemical vapor deposition method.
Specifically, a PCVD gas phase doping process is adopted to prepare fluorine-doped inner cladding sleeves (namely a first fluorine-doped inner cladding 2 and a second fluorine-doped inner cladding 3) with relative refractive index differences delta n2 and delta n3 of-0.03 percent and-1.2 percent respectively, and the designed optical rod section is prepared by adjusting the moving speed and the number of deposition passes of a reaction zone.
S3, preparing the outer cladding layer 4 by using an outer tube deposition method.
Specifically, O is introduced2、C2F6Reaction is carried out to remove water, and pure quartz outer cladding with proper proportion is prepared by OVD according to the core cladding ratio.
S4, combining the core layer 1, the first fluorine-doped inner cladding layer 2, the second fluorine-doped inner cladding layer 3 and the outer cladding layer 4 to manufacture the optical fiber prefabricated rod.
And S5, drawing the optical fiber preform to obtain the superstrong bending-resistant and irradiation-resistant optical fiber.
The preparation method of the superstrong bending-resistant irradiation-resistant optical fiber provided by the invention fully exerts the characteristic advantages of the processes of a reduced pressure plasma chemical vapor deposition (SPCVD) method and a Plasma Chemical Vapor Deposition (PCVD) method, the SPCVD method is adopted to prepare the core layer of the irradiation-resistant optical fiber, the PCVD method is adopted to prepare the double inner cladding layers of the irradiation-resistant optical fiber, the OVD method is adopted to prepare the outer cladding layers of the irradiation-resistant optical fiber, and the preparation method is simple and efficient.
The present invention is not limited to the above-described embodiments, and it will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and such modifications and improvements are also considered to be within the scope of the present invention. Those not described in detail in this specification are within the skill of the art.

Claims (10)

1. The superstrong bending-resistant and irradiation-resistant optical fiber comprises a core layer (1), an inner cladding layer and an outer cladding layer (4) which are sequentially arranged from inside to outside, wherein the core layer (1), the inner cladding layer and the outer cladding layer (4) are made of quartz, and the inner cladding layer comprises a first fluorine-doped inner cladding layer (2) and a second fluorine-doped inner cladding layer (3) which are sequentially arranged from inside to outside; wherein the core layer (1) is doped with nitrogen element.
2. The super-bending-resistant radiation-resistant optical fiber according to claim 1, wherein the content of nitrogen doped in the core layer (1) is greater than 0 and less than or equal to 3.5% by mass percent.
3. The super-bending-resistant and irradiation-resistant optical fiber according to claim 1, wherein the content of fluorine doped in the first fluorine-doped inner cladding (2) is greater than 0 and less than or equal to 2.0% by mass; the content of fluorine element doped in the second fluorine-doped inner cladding (3) is 3.0-6.0%.
4. The ultra-strong bend-resistant radiation-resistant optical fiber according to claim 1, wherein the outer cladding layer (4) is made of pure quartz.
5. The ultra-strong bending-resistant radiation-resistant optical fiber according to claim 1, wherein the refractive index profile of the core layer (1) is in a step type or a gradient type.
6. The super bend-resistant radiation-resistant optical fiber according to claim 5, wherein when the refractive index profile of the core layer (1) is stepped, the relative refractive index difference Δ n1 between the core layer (1) and the outer cladding layer (4) is in the range of 0 < Δ n1 < 1.0%.
7. The super bend-resistant radiation-resistant optical fiber according to claim 5, wherein when the refractive index profile of the core layer (1) is graded, the relative refractive index difference Δ n1 between the core layer (1) and the outer cladding layer (4) is larger than the relative refractive index difference Δ n1max0.9% -2.1%, and the distribution power function α is 1.8-2.2.
8. The ultra-strong bending-resistant radiation-resistant optical fiber according to claim 1, wherein the relative refractive index difference Δ n2 between the first fluorine-doped inner cladding layer (2) and the outer cladding layer (4) is in the range of-0.3% to Δ n2 to 0; the value range of the relative refractive index difference delta n3 between the second fluorine-doped inner cladding (3) and the outer cladding (4) is more than or equal to-1.5% and less than delta n3 and less than 0.
9. The ultra-strong bending-resistant radiation-resistant optical fiber according to any one of claims 1 to 8,
the superstrong bending-resistant radiation-resistant optical fiber is a single-mode optical fiber, a 50 mu m multimode optical fiber or a 62.5 mu m multimode optical fiber;
when the superstrong bending-resistant radiation-resistant optical fiber is a single-mode optical fiber, the diameter d1 of the core layer (1) is 8-10 mu m, the diameter d2 of the first fluorine-doped inner cladding layer (2) is 15-21 mu m, the diameter d3 of the second fluorine-doped inner cladding layer (3) is 28-35 mu m, and the diameter d4 of the outer cladding layer (4) is 125 mu m;
when the superstrong bending-resistant radiation-resistant optical fiber is a 50-micrometer multimode optical fiber, the diameter d1 of the core layer (1) is 48-52 micrometers, the diameter d2 of the first fluorine-doped inner cladding layer (2) is 48-56 micrometers, the diameter d3 of the second fluorine-doped inner cladding layer (3) is 56-66 micrometers, and the diameter d4 of the outer cladding layer (4) is 125 micrometers;
when the superstrong bending-resistant radiation-resistant optical fiber is a 62.5-micrometer multimode optical fiber, the diameter d1 of the core layer (1) is 60-65 micrometers, the diameter d2 of the first fluorine-doped inner cladding layer (2) is 60-70 micrometers, the diameter d3 of the second fluorine-doped inner cladding layer (3) is 70-80 micrometers, and the diameter d4 of the outer cladding layer (4) is 125 micrometers.
10. A method for preparing the ultra-strong bending-resistant radiation-resistant optical fiber according to any one of claims 1 to 9, comprising the following steps:
preparing a core layer (1) doped with nitrogen element by adopting a reduced pressure plasma chemical vapor deposition method;
preparing a first fluorine-doped inner cladding layer (2) and a second fluorine-doped inner cladding layer (2) by adopting a plasma chemical vapor deposition method;
preparing an outer cladding layer (4) by using a tube outside deposition method;
combining the core layer (1), the first fluorine-doped inner cladding layer (2), the second fluorine-doped inner cladding layer (3) and the outer cladding layer (4) to prepare an optical fiber prefabricated rod;
and drawing the optical fiber preform to obtain the superstrong bending-resistant and irradiation-resistant optical fiber.
CN202010247467.1A 2020-03-31 2020-03-31 Superstrong bending-resistant radiation-resistant optical fiber and preparation method thereof Active CN111458788B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010247467.1A CN111458788B (en) 2020-03-31 2020-03-31 Superstrong bending-resistant radiation-resistant optical fiber and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010247467.1A CN111458788B (en) 2020-03-31 2020-03-31 Superstrong bending-resistant radiation-resistant optical fiber and preparation method thereof

Publications (2)

Publication Number Publication Date
CN111458788A true CN111458788A (en) 2020-07-28
CN111458788B CN111458788B (en) 2022-05-20

Family

ID=71685767

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010247467.1A Active CN111458788B (en) 2020-03-31 2020-03-31 Superstrong bending-resistant radiation-resistant optical fiber and preparation method thereof

Country Status (1)

Country Link
CN (1) CN111458788B (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6125225A (en) * 1996-12-20 2000-09-26 Nauchny Tsenir Volokonnoi Optiki Pri Institute Obschei Fiziki Rossiiskoi Akademii Nauk Mode field diameter conversion fiber, method for locally changing a refractive index of optical waveguides and method for fabricating optical waveguide preforms
US20010002941A1 (en) * 1997-07-25 2001-06-07 Borrelli Nicholas Francis Photoinduced grating in oxynitride glass
CN101750670A (en) * 2008-12-08 2010-06-23 德雷卡通信技术公司 Ionizing radiation-resistant optical fibre amplifier
CN103543491A (en) * 2013-11-08 2014-01-29 烽火通信科技股份有限公司 Ultralow-loss high-bandwidth irradiation-resistance multimode fiber and manufacturing method thereof
CN105676349A (en) * 2016-04-06 2016-06-15 武汉邮电科学研究院 Bend-insensitive radiation-resistant single-mode fiber
CN110510885A (en) * 2019-08-28 2019-11-29 山东省科学院激光研究所 A kind of preparation method of optical fiber type NV colour center mono-/multi- photon source

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6125225A (en) * 1996-12-20 2000-09-26 Nauchny Tsenir Volokonnoi Optiki Pri Institute Obschei Fiziki Rossiiskoi Akademii Nauk Mode field diameter conversion fiber, method for locally changing a refractive index of optical waveguides and method for fabricating optical waveguide preforms
US20010002941A1 (en) * 1997-07-25 2001-06-07 Borrelli Nicholas Francis Photoinduced grating in oxynitride glass
CN101750670A (en) * 2008-12-08 2010-06-23 德雷卡通信技术公司 Ionizing radiation-resistant optical fibre amplifier
CN103543491A (en) * 2013-11-08 2014-01-29 烽火通信科技股份有限公司 Ultralow-loss high-bandwidth irradiation-resistance multimode fiber and manufacturing method thereof
CN105676349A (en) * 2016-04-06 2016-06-15 武汉邮电科学研究院 Bend-insensitive radiation-resistant single-mode fiber
CN110510885A (en) * 2019-08-28 2019-11-29 山东省科学院激光研究所 A kind of preparation method of optical fiber type NV colour center mono-/multi- photon source

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
苏君红 等: "《光纤材料技术》", 30 April 2009, 浙江科学技术出版社 *

Also Published As

Publication number Publication date
CN111458788B (en) 2022-05-20

Similar Documents

Publication Publication Date Title
EP1876150B1 (en) Radiation-resistant fluorine doped optical fiber
US8295668B2 (en) Low loss optical fiber designs and methods for their manufacture
EP1813581B1 (en) Method for manufacturing an optical fiber preform, optical fiber preform and optical fiber
KR101908735B1 (en) Single mode optical fiber
EP2726422B1 (en) Methods for producing optical fiber preforms with low index trenches
CN106772788B (en) Single mode fiber with cut-off wavelength displacement
GB2490264A (en) Optical waveguide
CN106324752B (en) A kind of anti-radiation multimode fibre of high bandwidth
CN112456788B (en) Polarization maintaining optical fiber for high power and preparation method thereof
CN104291676B (en) A kind of manufacture method of large scale bend-insensitive multimode optical fiber preform
CN103543491A (en) Ultralow-loss high-bandwidth irradiation-resistance multimode fiber and manufacturing method thereof
CN102126825B (en) Radiation-resistant high-performance silica fiber and preparation method thereof
JPS60257408A (en) Optical fiber and its production
CN109970335B (en) Large-size low-attenuation optical fiber preform and preparation method thereof
CN100383579C (en) High-property anti-radiation quartz optical fibre and manufacturing process of combined method
US6904213B2 (en) Step index optical fiber with doped cladding and core, a preform, and a method of fabricating such a fiber
CN111458788B (en) Superstrong bending-resistant radiation-resistant optical fiber and preparation method thereof
WO2012100581A1 (en) Bend-proof multimode optical fiber
JP2012171802A (en) Method for producing optical fiber preform
CN100368835C (en) High-performance anti-radiation quartz optical fiber and making method thereof
CN113716861A (en) Method for preparing bending insensitive optical fiber by external gas phase deposition method
CN112824943A (en) Radiation-insensitive single-mode fiber
CN220650930U (en) Low-attenuation large-mode-field-diameter bending insensitive single-mode optical fiber
CN117406336A (en) Radiation-resistant single-mode optical fiber
CN116520480A (en) Groove auxiliary type microbending-resistant single-mode optical fiber

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant