WO2021164443A1 - 一种细径光纤及其制备方法 - Google Patents

一种细径光纤及其制备方法 Download PDF

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WO2021164443A1
WO2021164443A1 PCT/CN2020/142343 CN2020142343W WO2021164443A1 WO 2021164443 A1 WO2021164443 A1 WO 2021164443A1 CN 2020142343 W CN2020142343 W CN 2020142343W WO 2021164443 A1 WO2021164443 A1 WO 2021164443A1
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optical fiber
layer
thin
diameter
refractive index
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PCT/CN2020/142343
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English (en)
French (fr)
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钱宜刚
吴椿烽
沈一春
沈海平
孙耀杰
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中天科技精密材料有限公司
江苏中天科技股份有限公司
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Publication of WO2021164443A1 publication Critical patent/WO2021164443A1/zh

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    • 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
    • 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
    • C03B37/01205—Manufacture of preforms for drawing fibres or filaments starting from tubes, rods, fibres or filaments
    • C03B37/01211—Manufacture of preforms for drawing fibres or filaments starting from tubes, rods, fibres or filaments by inserting one or more rods or tubes into a tube
    • 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]
    • C03B37/01446—Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
    • C03C17/28—Surface treatment of glass, not in the form of fibres or filaments, by coating with organic material
    • C03C17/30—Surface treatment of glass, not in the form of fibres or filaments, by coating with organic material with silicon-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
    • C03C17/34—Surface treatment of glass, not in the form of fibres or filaments, by coating with at least two coatings having different compositions
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C25/00—Surface treatment of fibres or filaments made from glass, minerals or slags
    • C03C25/10—Coating
    • C03C25/24—Coatings containing organic materials
    • C03C25/40—Organo-silicon compounds
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C25/00—Surface treatment of fibres or filaments made from glass, minerals or slags
    • C03C25/10—Coating
    • C03C25/48—Coating with two or more coatings having different compositions
    • C03C25/50—Coatings containing organic materials only
    • 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
    • G02B6/028—Optical fibres with cladding with or without a coating with core or cladding having graded refractive index
    • 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
    • G02B6/0365—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 arranged - - +

Definitions

  • This application relates to the field of optical fiber technology, and in particular to a thin-diameter optical fiber and a preparation method thereof.
  • optical fiber networks will carry the application of information networks, wide-area measurement, high-speed sensing, high-performance computing, and intelligent control, etc., which will inevitably be accompanied by a sharp increase in transmission capacity. Because of this, the amount of pipeline installation is obviously insufficient, and the deployment of new optical fibers requires a large amount of reinvestment. Therefore, in order to make full use of existing pipeline resources and reduce construction costs, laying more optical fibers in existing pipelines has become a preferred pipeline resource solution.
  • the diameter of the optical fiber is reduced, but it is required to have the same optical performance as the standard optical fiber, which means that one of the core problems of optical fiber miniaturization is to ensure that the transmission parameters remain unchanged.
  • one of the core problems of optical fiber miniaturization is to ensure that the transmission parameters remain unchanged.
  • fine-diameter fibers need better bending characteristics without affecting signal strength and transmission quality.
  • optical fiber miniaturization is mainly achieved by reducing the thickness of the coating or reducing the diameter of the bare fiber to achieve small size fibers. Whether reducing the thickness of the coating or reducing the diameter of the bare fiber, it will face the requirements of fiber bending characteristics and fiber splicing compatibility issues. Therefore, in order to solve the above problems, the space for reducing the coating or bare fiber is limited. Compared with the standard fiber (the diameter of the bare fiber is 125 microns, the outer diameter of the coating layer is 250 microns), the diameter of the existing miniaturized fiber is generally 200 microns ( The diameter of the bare fiber is 125 microns, and the outer diameter of the coating layer is 200 microns).
  • the prior art proposes a design of a low-diameter optical fiber, the diameter of the bare optical fiber is 100-125 microns, and the optical fiber mainly uses a new coating material to meet the requirements of protecting the bare optical fiber.
  • This design reduces the thickness of the coating, but the new coating material used is expensive, and the corresponding curing of the coating has a series of difficulties.
  • the prior art also proposes an optical fiber with a reduced diameter.
  • the mode field diameter (MFD) of this type of optical fiber is greatly reduced, and large connection loss is likely to occur after fusion splicing with a standard optical fiber.
  • the purpose of the present application is to provide a thin-diameter optical fiber and a preparation method thereof.
  • the optical fiber provided in the present application has a smaller diameter and better performance.
  • the application provides a thin-diameter optical fiber, including: a bare optical fiber and a coating layer covering the outer layer of the bare optical fiber.
  • the bare optical fiber includes a core layer, an optical cladding layer covering the surface of the core layer, a recessed layer covering the surface of the optical cladding layer, and an outer covering layer covering the surface of the recessed layer.
  • the coating layer preferably includes an inner coating layer and an outer coating layer; the inner coating layer covers the surface of the outer coating layer, and the outer coating layer covers the inner coating layer. The surface of the coating.
  • the structure diagram of the thin-diameter optical fiber provided by the embodiments of the present application is shown in FIG. 6, and includes: a core layer 1; an optical cladding layer 2 covering the surface of the core layer 1; Recessed layer 3; outer coating 4 covering the surface of the recessed layer 3; inner coating 5 covering the surface of the outer coating 4; outer coating covering the surface of the inner coating 5 6.
  • ⁇ n 100% ⁇ (n i -n siO2 )/n siO2
  • n i is the refractive index of silica glass doped with i element
  • n siO2 is the refractive index of pure silica glass.
  • doping germanium can increase the relative refractive index of silica glass; doping fluorine can decrease the relative refractive index of silica glass.
  • the layer refractive index is the refractive index of silicon dioxide doped with germanium.
  • the relative refractive index difference of the core layer is preferably 0.3 to 0.35%, more preferably 0.31 to 0.34%, and most preferably 0.32 to 0.33%.
  • the relative refractive index difference of the core layer is preferably kept constant from the inside to the outside, that is, the relative refractive index difference from the center of the core layer to the surface of the core layer does not change.
  • the radius of the core layer is preferably 3 to 5 microns, more preferably 4 microns.
  • the material of the optical cladding layer is preferably a fluorine-doped silicon dioxide material, such as SiF 4 , CF 4 , SF 6 , C 2 F 6 , SOF 2 , C 2 F 2 Cl 2
  • a fluorine-doped silicon dioxide material such as SiF 4 , CF 4 , SF 6 , C 2 F 6 , SOF 2 , C 2 F 2 Cl 2
  • the relative refractive index difference of the optical cladding layer is gradually gradual from the inside to the outside, and the range of the gradation is +0.05 ⁇ -0.10%, preferably +0.03 ⁇ -0.05%, more preferably +0.01 ⁇ -0.01%; That is, the relative refractive index difference of the part of the optical cladding layer close to the core layer to the relative refractive index difference of the part of the optical cladding layer close to the recessed layer changes from +0.05% to -0.10%.
  • the present application does not have special restrictions on the way of gradual change, and it is preferably a linear way of gradual change.
  • the radius of the optical cladding is preferably 10-25 microns, more preferably 15-20 microns, and the radius of the optical cladding refers to the distance from the center of the core layer to the surface of the optical cladding, which includes The radius of the core layer.
  • the thickness of the optical cladding layer is the radius of the optical cladding layer minus the radius of the core layer, preferably 10-15 microns, more preferably 11-14 microns, most preferably 12-13 microns.
  • the material of the recessed layer is preferably a silicon dioxide material doped with fluorine elements, such as SiF 4 , CF 4 , SF 6 , C 2 F 6 , SOF 2 , C 2 F 2 Cl 2
  • fluorine elements such as SiF 4 , CF 4 , SF 6 , C 2 F 6 , SOF 2 , C 2 F 2 Cl 2
  • the relative refractive index difference of the recessed layer is preferably 0 to -0.6%, more preferably -0.25 to -0.6%, more preferably -0.3 to -0.5%, and most preferably -0.4%.
  • the relative refractive index difference of the recessed layer is preferably gradual from the inside to the outside, and the range of the gradation is -0.6 to 0%, preferably from -0.6 to -0.25%, the value is gradual to 0, that is, the recessed layer is close to the optical
  • the relative refractive index difference of the cladding layer to that of the recessed layer near the outer cladding layer is gradually changed from -0.6% to -0.25% to zero.
  • the present application does not have special restrictions on the way of gradual change, and it is preferably a linear way of gradual change.
  • the radius of the recessed layer is preferably 15-30 microns, more preferably 20-25 microns.
  • the radius of the recessed layer refers to the distance from the center of the core layer to the surface of the recessed layer, which includes the optical cladding layer. ⁇ radius.
  • the thickness of the recessed layer is the difference between the radius of the recessed layer and the radius of the optical cladding layer, preferably 5-15 microns, more preferably 8-12 microns, most preferably 10 microns.
  • the optical cladding in the thin-diameter fiber profile is designed to be gradual, which is beneficial to increase the MFD value of the fiber and make it close to or equal to the standard fiber; the recessed layer decreases from the inside to the outside, on the one hand, it can effectively restrain the light from leaking. , To ensure the requirements of optical fiber macrobending; on the other hand, it is more conducive to control the cut-off wavelength of the optical fiber to meet the requirements of optical fiber transmission.
  • the material of the outer cladding layer is preferably pure silica material, and the relative refractive index difference is 0 by default.
  • the radius of the outer cladding layer is preferably 38-45 microns, more preferably 40-42 microns.
  • the outer cladding layer radius refers to the distance from the center of the core layer to the surface of the outer cladding layer, which includes the radius of the recessed layer.
  • the thickness of the outer cover is the difference between the radius of the outer cover and the radius of the recessed layer, preferably 10-15 microns, more preferably 11-14 microns, most preferably 12-13 microns.
  • the S recessed layer is the area of the recessed layer
  • S core layer is the area of the core layer
  • r1, r2, r3 are the radii of the core layer, optical cladding layer, and recessed layer, respectively;
  • ⁇ n1 is the relative refractive index difference of the core layer
  • ⁇ n3 is the relative refractive index difference of the recessed layer
  • the S recess layer /S core layer is preferably 2-6, more preferably 3-5, and most preferably 4.
  • the area of the recessed layer in the cross-sectional structure of the thin-diameter optical fiber is 2-6 times the area of the core layer, which can realize the bending resistance of the thin-diameter optical fiber.
  • composition of the coating layer is preferably selected from urethane acrylate, polysiloxane acrylate, epoxy acrylate or polyester acrylate.
  • the thickness of the coating layer is preferably 35 to 45 microns, more preferably 38 to 42 microns, and most preferably 40 microns.
  • the components of the inner coating layer are preferably selected from urethane acrylate, polysiloxane acrylate, epoxy acrylate or polyester acrylate, and the thickness of the inner coating layer is preferably 15-30 microns. , More preferably 20-25 microns, most preferably 23 microns; the composition of the outer coating layer is preferably selected from urethane acrylate, polysiloxane acrylate, epoxy acrylate or polyester acrylate.
  • the thickness of the coating layer is preferably 10-25 microns, more preferably 15-20 microns, and most preferably 17 microns.
  • the elastic modulus of the inner coating layer is preferably 0.5 to 3 MPa, more preferably 1 to 2.5 MPa, and most preferably 1.5 to 2 MPa; the elastic modulus of the outer coating layer is preferably 1000 to 2000 MPa, It is more preferably 1200 to 1800 MPa, and most preferably 1400 to 1600 MPa.
  • the diameter (d) of the bare optical fiber is preferably 76-90 microns, more preferably 80-85 microns; the diameter (D) of the thin-diameter optical fiber is preferably 155-175 microns, more preferably 160 ⁇ 170 microns, most preferably 165 microns.
  • the volume of the thin-diameter optical fiber in the pipeline is preferably:
  • D is the outer diameter of the thin-diameter optical fiber coating
  • L is the unit length of the optical fiber.
  • the volume ratio of the thin-diameter fiber is V min / Vst , where V min is the volume of the thin-diameter fiber; and V st is the volume of the standard fiber.
  • the occupancy rate of the pipe volume of the thin-diameter optical fiber in this application is 50% of that of the standard optical fiber (the outer diameter of the coating layer is 250 microns), which greatly improves the utilization rate of pipe resources.
  • the thin-diameter optical fiber provided by this application has a mode field diameter of 8.4-9.2 microns, a cable wavelength of less than 1260 nm, a zero-dispersion wavelength of 1310 to 1324 m, and an attenuation of less than 0.35 dB/km and 0.25 dB/km at 1310 and 1550 nm wavelengths, respectively.
  • the bending radius R is 7.5mm
  • the bending loss at 1550nm and 1625nm wavelength are lower than 0.3dB and 0.5dB respectively; the tensile strength of 0.5m under 15% and 50% conditions is ⁇ 420kpsi and 480kpsi respectively.
  • the present application provides a method for preparing the thin-diameter optical fiber described in the above technical solution, including:
  • a coating layer is prepared on the surface of the preform to obtain a thin-diameter optical fiber.
  • This application does not have any special restrictions on the preparation method of the core layer, as long as the core layer preparation method is well known to those skilled in the art, such as VAD equipment for deposition, and oxygen, hydrogen, silicon tetrachloride, and four Germanium chloride and Ar gas are reacted at high temperature to form silicon dioxide and germanium dioxide is attached to the end surface of the target rod; after the deposition is completed, dehydroxylation and vitrification and sintering are carried out to obtain the core layer.
  • a core layer with a certain relative refractive index difference This application does not have special restrictions on the temperature of the dehydroxylation and vitrification and sintering. Those skilled in the art can select a suitable temperature for dehydroxylation and vitrification and sintering according to the actual situation, preferably by introducing chlorine gas for dehydroxylation.
  • the optical cladding can be prepared according to the preparation method of the core layer described in the above technical scheme Firstly, use VAD equipment for deposition. Oxygen, hydrogen, silicon tetrachloride, and Ar gas are introduced into the burner for deposition. After the deposition is completed, dehydroxylation and vitrification and sintering are carried out. During the process of vitrification and sintering, fluoride gas and fluorine are introduced.
  • the flow rate of the compound gas increases linearly until the end of sintering to obtain the optical cladding, and the relative refractive index difference of the optical cladding is gradually changed by controlling the linear increase of the fluoride gas flow.
  • the fluoride is preferably selected from one or a combination of at least two of SiF 4 , CF 4 , SF 6 , C 2 F 6 , SOF 2 and C 2 F 2 Cl 2.
  • This application does not have special restrictions on the preparation method of the recessed layer, and it can be prepared by the preparation method of the recessed layer well known to those skilled in the art.
  • the surface of the outer cladding layer is deposited layer by layer, and SiCl 4 , O 2 , and fluoride are passed into the torch to form a fluorine-containing glass layer.
  • the fluoride is preferably selected from one or a combination of at least two of SiF 4 , CF 4 , SF 6 , C 2 F 6 , SOF 2 and C 2 F 2 Cl 2.
  • the change in refractive index in each layer is achieved by controlling the flow rate of the dopant (germanium tetrafluoride or fluoride); it is more preferable to prepare the optical cladding layer and the recessed layer.
  • the gradual change of refractive index is achieved by controlling the flow rate of the dopant.
  • the method of high temperature homogenization treatment preferably includes:
  • FIG. 5 a schematic diagram of the high temperature homogenization treatment is shown in FIG. 5.
  • This application adopts the above-mentioned high-temperature homogenization treatment process, and uses the slow high-temperature creep and annealing characteristics to effectively improve the local structural inhomogeneity in the quartz glass of the preform and the micro-defects and stress on the boundary of each layer, and at the same time, realize the boundary area
  • the internal doping diffusion relieves the micro-stress caused by the different thermal expansion coefficients of the doping on the boundary of each layer; in addition, the vacuum + pressurization + vacuum method is used to promote the air bubbles in the quartz glass to move out of the rod body and eliminate the inside of the rod. Tiny bubbles.
  • the time for raising the temperature from room temperature is preferably 2.5 hours
  • the temperature for raising the temperature is preferably 1300 to 1450°C, more preferably 1350 to 1400°C
  • the constant temperature time is preferably 12 to 18 hours, more preferably 14 to 16 hours
  • the degree of vacuum is preferably -0.4 ⁇ -0.5bar
  • N 2 is charged to keep the pressure preferably 0.3 ⁇ 0.4bar
  • the constant temperature is preferably 1200 ⁇ 1400°C, more preferably 1250 ⁇ 1350°C, most preferably 1300°C
  • constant temperature time Preferably it is 5h.
  • the vacuum degree of the re-evacuation is preferably -0.4 to -0.5 bar
  • the constant temperature temperature is preferably 1300 to 1450°C, more preferably 1350 to 1400°C
  • the constant temperature time is preferably 16 to 20 hours.
  • the cooling rate is preferably 2 to 6°C/min, more preferably 3 to 5°C/min, and most preferably 4°C/min.
  • the preparation method of the outer covering layer is preferably vapor deposition or assembling a sleeve outside the core rod.
  • This application has no special restrictions on the vapor deposition method or the method of assembling the sleeve.
  • the outer coating can be prepared by the above-mentioned method well known to those skilled in the art, such as placing the mandrel after the high-temperature treatment on the OVD machine. Deposition, after reaching the target weight or rod diameter, the deposition is completed, and then sintering is performed to obtain the outer coating; or the core rod after the high temperature treatment is directly assembled into the silica sleeve to obtain the outer coating.
  • the present application does not have special restrictions on the preparation method of the coating layer, and the coating layer with the above composition and thickness can be prepared by the preparation method of the coating layer well known to those skilled in the art.
  • the optical cladding in the cross-section has a gradual design, which is beneficial to increase the MFD value of the optical fiber and make it close to or equal to the standard optical fiber; At the same time, it is also beneficial to control the cut-off wavelength of the optical fiber to meet the requirements of optical fiber transmission.
  • this application adopts a high-temperature homogenization treatment process, which can effectively improve the local structural inhomogeneity in the quartz glass of the preform and the micro-defects and stress on the boundary of each layer, and alleviate the doping of substances with different thermal expansion coefficients on the boundary of each layer. Micro stress; at the same time, it can effectively eliminate the tiny bubbles in the rod.
  • This application can be widely used in the quartz glass processing industry.
  • Fig. 1 is a schematic diagram of the refractive index profile of a thin-diameter optical fiber prepared in Example 1 of the application;
  • FIG. 2 is a schematic diagram of the refractive index profile of the thin-diameter optical fiber prepared in Example 2 of the application;
  • FIG. 3 is a schematic diagram of the refractive index profile of the thin-diameter optical fiber prepared in Example 3 of the application;
  • Example 4 is a cross-sectional distribution diagram of the thin-diameter optical fiber prepared in Example 4 of the application;
  • FIG. 5 is a schematic diagram of high temperature treatment temperature provided by an embodiment of the application.
  • Fig. 6 is a schematic structural diagram of a cross-section of a thin-diameter optical fiber provided by this application;
  • Fig. 7 is a cross-sectional distribution diagram of the thin-diameter optical fiber prepared in Comparative Example 1 of the application;
  • FIG. 8 is a schematic diagram of the refractive index profile of the thin-diameter optical fiber prepared in Comparative Example 2 of this application.
  • SiCl 4 , GeCl 4 , C 2 F 6 are used as raw materials.
  • the gas flow rate and ratio, as well as the movement speed of the reaction zone and the number of deposition passes, are prepared to meet the design requirements of the optical fiber preform profile.
  • the OVD process is used to prepare the outer coating according to the set outer weight to obtain the finished preform, and then two coats are applied to obtain the thin-diameter optical fiber; when drawing, the elastic modulus of the inner coating of the thin-diameter optical fiber is 0.5 MPa, the elastic modulus of the outer coating is 1000 MPa.
  • the IFA-100 type optical fiber refractive index tester provided by Interfiber Corporation of the United States was used to test the refractive index profile data of the thin-diameter optical fiber prepared in Example 1 of the application (the refractive index profile schematic diagram is shown in Figure 1), and the test results are shown in the table As shown in 1 ( ⁇ n1 is the relative refractive index difference of the core layer, ⁇ n2 is the relative refractive index difference of the optical cladding layer, ⁇ n3 is the relative refractive index difference of the recessed layer, r1 is the core layer radius, r2 is the optical cladding layer radius, r3 is The radius of the depressed layer, r4 is the radius of the outer cladding layer, d is the diameter of the bare fiber (without the coating layer), and D is the diameter of the small-diameter fiber).
  • the OTDR, PK2200, and dispersion meter of PK Company of the United States were used to test the optical performance of the thin-diameter fiber prepared in Example 1 of this application; the two-point bending method (according to GB/T15972.31-2008 "Optical fiber test method specification part 31": The measurement method and test procedure of mechanical properties—Tensile Strength>Standard Method) were used to test the mechanical properties of the thin-diameter optical fiber prepared in Example 1 of the present application. The test results are shown in Table 2.
  • SiCl 4 , GeCl 4 , and SiF 4 are used as raw materials.
  • a core that meets the design requirements of the optical fiber preform profile is prepared by changing the gas flow rate and ratio, as well as the moving speed of the reaction zone and the number of deposition passes.
  • Layer, optical cladding layer, recessed layer; among them, the prepared powder rod is processed by chlorine gas for dehydroxylation during the sintering process to finally form a transparent glass rod.
  • the OVD process is used to prepare an outer covering according to the set outer covering weight to obtain a preform, and then coat two layers of coatings to obtain a thin-diameter optical fiber.
  • the elastic modulus of the inner coating of the thin-diameter optical fiber is 0.5 MPa
  • the elastic modulus of the outer coating is 2000 MPa.
  • Example 2 the refractive index profile data of the thin-diameter optical fiber prepared in Example 2 of the present application was tested (the schematic diagram of the refractive index profile is shown in FIG. 2), and the test results are shown in Table 1.
  • Example 2 According to the method of Example 1, the optical properties and mechanical properties of the thin-diameter optical fiber prepared in Example 2 of the present application were tested, and the test results are shown in Table 2.
  • SiCl 4 , GeCl 4 , SF 6 , and Cl 2 are used as raw materials.
  • the gas flow rate and ratio, as well as the moving speed of the reaction zone and the number of deposition passes, are prepared to meet the design requirements of the optical fiber preform profile.
  • the core layer, optical cladding layer, and recessed layer are shrunk to form a transparent glass rod.
  • the quartz sleeve is used for matching, assembled to obtain a preform, and two layers of coating are applied to obtain a thin-diameter optical fiber.
  • the elastic modulus of the inner coating of the thin-diameter optical fiber is 3 MPa
  • the elastic modulus of the outer coating is 2000 MPa.
  • Example 1 the refractive index profile data of the thin-diameter optical fiber prepared in Example 3 of the present application was tested (a schematic diagram of the refractive index profile is shown in FIG. 3), and the test results are shown in Table 1.
  • Example 2 According to the method of Example 1, the optical properties and mechanical properties of the thin-diameter optical fiber prepared in Example 3 of the present application were tested, and the test results are shown in Table 2.
  • the core layer which meets the design requirements of the optical fiber preform profile, is prepared by changing the gas flow rate and ratio, as well as the moving speed of the reaction zone and the number of deposition passes.
  • Optical cladding and recessed layer; among them, the prepared powder rods are treated with chlorine gas during the sintering process to finally form a transparent glass rod.
  • the quartz sleeve is used for matching, assembled to obtain a preform, and two layers of coating are applied to obtain a thin-diameter optical fiber.
  • the elastic modulus of the inner coating of the thin-diameter optical fiber is 1.5 MPa
  • the elastic modulus of the outer coating is 1500 MPa.
  • the IFA-100 type optical fiber refractive index tester provided by American Interfiber Company was used to test the profile distribution of the thin-diameter optical fiber prepared in Example 4. The test result is shown in Fig. 4. From the graph, the connection at the boundary is smooth and there are no visible defects.
  • Example 1 the refractive index profile data of the thin-diameter optical fiber prepared in Example 4 of the present application was tested, and the test results are shown in Table 1.
  • Example 2 According to the method of Example 1, the optical properties and mechanical properties of the thin-diameter fiber prepared in Example 4 of the present application were tested, and the test results are shown in Table 2.
  • the core layer which meets the design requirements of the optical fiber preform profile, is prepared by changing the gas flow rate and ratio, as well as the moving speed of the reaction zone and the number of deposition passes.
  • Optical cladding and recessed layer among them, the prepared powder rods undergo dehydroxylation treatment with chlorine gas during the sintering process, and finally form transparent glass rods.
  • the glass rod prepared above is matched with a quartz sleeve, assembled to obtain a preform, and coated with two layers of coating to obtain an optical fiber.
  • the elastic modulus of the inner coating of the optical fiber is 1.5 MPa
  • the elastic modulus of the outer coating is 1500 MPa.
  • SiCl 4 , GeCl 4 , and SiF 4 are used as raw materials.
  • a core that meets the design requirements of the optical fiber preform profile is prepared by changing the gas flow rate and ratio, as well as the moving speed of the reaction zone and the number of deposition passes.
  • Layer, optical cladding layer, recessed layer; among them, the prepared powder rod is processed by chlorine gas for dehydroxylation during the sintering process to finally form a transparent glass rod.
  • the glass rod prepared above is used OVD process to prepare an outer covering according to the set outer covering weight, to obtain a preform, and to coat two layers of coatings to obtain an optical fiber.
  • the elastic modulus of the inner coating of the optical fiber is 0.5 MPa
  • the elastic modulus of the outer coating is 2000 MPa.
  • the refractive index profile data of the thin-diameter optical fiber prepared in Comparative Example 2 of the present application was tested (the schematic diagram of the refractive index profile is shown in FIG. 8), and the test results are shown in Table 1.
  • the use of an optical cladding with a graded refractive index is more conducive to increasing the value of MFD (mode field diameter); the optical fiber with a graded recessed layer design can ensure a slightly lower cable wavelength while ensuring macrobending. It is the cable wavelength of the non-graded index profile fiber.
  • the tensile strength of the optical fiber is better than that of the non-high temperature treatment optical fiber.
  • the present application provides a thin-diameter optical fiber, including: a bare optical fiber; a coating layer covering the outer layer of the bare optical fiber; the bare optical fiber including: a core layer; The optical cladding on the surface of the optical cladding; the recessed layer covering the surface of the optical cladding; the outer cladding covering the surface of the recessed layer; the relative refractive index difference of the optical cladding gradually changes from the inside to the +0.05 ⁇ -0.10%.
  • the optical cladding in the cross-section is designed with a gradual change, which is beneficial to increase the MFD value of the optical fiber and make it close to or equal to the standard optical fiber; further, the recessed layer gradual structural design ensures that the optical fiber In addition to the macrobending requirements, it is also beneficial to control the cut-off wavelength of the optical fiber to meet the requirements of optical fiber transmission.

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Abstract

一种细径光纤，包括：裸光纤；包覆在裸光纤外层的涂覆层（5，6）；裸光纤包括：芯层（1）；包覆在芯层（1）表面的光学包层（2）；包覆在光学包层（2）表面的凹陷层（3）；包覆在凹陷层（3）表面的外包层（4）；光学包层（2）的相对折射率差从内向外渐变，渐变范围为+0.05～-0.10％。通过设计预制棒的剖面结构，使其剖面中光学包层（2）渐变式设计，有利于提高光纤的MFD值，使之与标准光纤接近或相等；进一步的，凹陷层（3）渐变式结构设计，保证光纤宏弯要求的同时，也利于控制光纤的截止波长，满足光纤传输要求。还提供了一种细径光纤的制备方法。

Description

一种细径光纤及其制备方法 技术领域
本申请涉及光纤技术领域，尤其涉及一种细径光纤及其制备方法。
背景技术
随着未来通信领域的发展，光纤网络将承载信息网络、广域测量、高速传感、高性能计算以及智能控制等技术的应用，也必然伴随着传输容量的急剧增加。正因如此，管道敷设量突显明显不足，而新增光纤部署需要重新投入大量成本。因此，为了充分利用现有管道资源、降低建设成本，在现有管道中敷设更多的光纤成为优选的管道资源解决方案。
光纤直径降低，但是要求具有与标准光纤相同的光学性能，也就意味着解决光纤小型化的核心问题之一就是保证传输参数不变，同时，当管道中光纤密度增加后空间内存在更多的弯曲，此时，细径光纤需要更好的弯曲特性而不影响信号强度和传输质量。
目前光纤小型化主要是通过降低涂层厚度或者降低裸光纤直径来实现小尺寸光纤，不论是降低涂层厚度还是降低裸光纤直径，都会面临光纤的弯曲特性要求以及光纤接续兼容性问题。因此，为了解决上述问题，涂层或裸光纤降低空间有限，相比标准光纤而言(裸光纤直径125微米、涂覆层外径250微米)，现有小型化光纤的直径一般在200微米(裸光纤直径125微米、涂覆层外径200微米)。
现有技术提出了一种低直径光纤的设计，裸光纤直径100～125微米，该光纤主要是使用新的涂覆层材料，满足保护裸光纤的要求。这种设计降低了涂层厚度，但使用的新涂覆层材料成本昂贵，相应的涂覆层固化等都具有一系列困难。现有技术还提出了一种直径降低后的 光纤，这类光纤模场直径(MFD)大幅降低，与标准光纤熔接后容易产生大的连接损耗。
因此，研究一种直径小而且性能好的光纤成为本领域技术人员关注的热点。
发明内容
有鉴于此，本申请的目的在于提供一种细径光纤及其制备方法，本申请提供的光纤直径较小而且性能较好。
本申请提供了一种细径光纤，包括：裸光纤及包覆在所述裸光纤外层的涂覆层。所述裸光纤包括：芯层、包覆在所述芯层表面的光学包层、包覆在所述光学包层表面的凹陷层及包覆在所述凹陷层表面的外包层。
在本申请中，所述涂覆层优选包括内涂覆层和外涂覆层；所述内涂覆层包覆在所述外包层的表面，所述外涂覆层包覆在所述内涂覆层的表面。
本申请实施例提供的细径光纤的结构示意图如图6所示，包括：芯层1；包覆在所述芯层1表面的光学包层2；包覆在所述光学包层2表面的凹陷层3；包覆在所述凹陷层3表面的外包层4；包覆在所述外包层4表面的内涂覆层5；包覆在所述内涂覆层5表面的外涂覆层6。
在本申请中，所述裸光纤中各层的相对折射率差表示为：
△n＝100％×(n i-n siO2)/n siO2
其中，n i是掺i元素的二氧化硅玻璃折射率；
n siO2是纯二氧化硅玻璃折射率。
在本申请中，所述裸光纤中各层的材质优选掺氟元素的二氧化硅材料层；相对折射率差表示为：△n＝100％×(n F-n siO2)/n siO2，n F是掺氟元素的二氧化硅玻璃的折射率。
在本申请中，掺锗能够提高石英玻璃的相对折射率；掺氟能够降低石英玻璃的相对折射率。
在本申请中，所述芯层的材质优选为掺锗元素的二氧化硅材料；相对折射率差表示为：△n＝100％×(n Ge-n siO2)/n siO2，n Ge是芯层折射率即掺锗元素的二氧化硅的折射率。在本申请中，所述芯层的相对折射率差优选为0.3～0.35％，更优选为0.31～0.34％，最优选为0.32～0.33％。在本申请中，所述芯层的相对折射率之差优选从内向外保持恒定，即从芯层的中心到芯层的表面相对折射率之差不变。
在本申请中，所述芯层的半径优选为3～5微米，更优选为4微米。
在本申请中，所述光学包层的材质优选为掺氟元素的二氧化硅材料，如掺入SiF 4、CF 4、SF 6、C 2F 6、SOF 2、C 2F 2Cl 2中的一种或至少两种组合的石英二氧化硅玻璃。
在本申请中，所述光学包层的相对折射率差从内向外渐变，渐变的范围为+0.05～-0.10％，优选为+0.03～-0.05％，更优选为+0.01～-0.01％；即光学包层靠近芯层部分的相对折射率差到光学包层靠近凹陷层部分相对折射率差从+0.05％渐变为-0.10％。本申请对所述渐变的方式没有特殊的限制，优选为线性方式渐变。
在本申请中，所述光学包层的半径优选为10～25微米，更优选为15～20微米，所述光学包层的半径指的是芯层中心到光学包层表面的距离，其包括芯层的半径长度。在本申请中，所述光学包层的厚度为光学包层的半径减去芯层的半径，优选为10～15微米，更优选为11～14微米，最优选为12～13微米。
在本申请中，所述凹陷层的材质优选为掺入氟元素的二氧化硅材料，如掺入SiF 4、CF 4、SF 6、C 2F 6、SOF 2、C 2F 2Cl 2中的一种或至少两种组合的石英二氧化硅玻璃。
在本申请中，所述凹陷层的相对折射率差优选为0～-0.6％，更优选为-0.25～-0.6％，更优选为-0.3～-0.5％，最优选为-0.4％。在本申请中，所述凹陷层的相对折射率差优选从内向外渐变，渐变的范围为-0.6～0％，优选为-0.6～-0.25％范围内值渐变至0，即凹陷层靠近光学包层部分的相对折射率差到凹陷层靠近外包层部分的相对折射率差 从-0.6％～-0.25％渐变到0。本申请对所述渐变的方式没有特殊的限制，优选为线性方式渐变。
在本申请中，所述凹陷层的半径优选为15～30微米，更优选为20～25微米，所述凹陷层的半径指的是芯层中心到凹陷层表面的距离，其包括光学包层的半径。在本申请中，所述凹陷层的厚度为凹陷层半径与光学包层半径之差，优选为5～15微米，更优选为8～12微米，最优选为10微米。
本申请中，细径光纤剖面中光学包层设计成渐变式，有利于提高光纤的MFD值，使之与标准光纤接近或相等；凹陷层由内向外递减，一方面可以有效约束光不发生泄露，保证光纤宏弯要求；另一方面更利于控制光纤的截止波长，满足光纤传输要求。
在本申请中，所述外包层的材质优选为纯二氧化硅材料，相对折射率差默认为0。
在本申请中，所述外包层的半径优选为38～45微米，更优选为40～42微米，所述外包层半径指的使芯层中心到外包层表面的距离，其包括凹陷层的半径。在本申请中，所述外包层的厚度为外包层半径与凹陷层半径之差，优选为10～15微米，更优选为11～14微米，最优选为12～13微米。
在本申请中，优选：
S 凹陷层/S 芯层＝[△n3*(r3-r2)]*[(1/2) 注]/[△n1*r1]；
其中，S 凹陷层为凹陷层的区域面积；
S 芯层为芯层的区域面积；
r1、r2、r3分别是芯层、光学包层、凹陷层的半径；
△n1为芯层相对折射率差；
△n3为凹陷层相对折射率差；
当凹陷层为渐变式呈三角形区域时，公式中需要增加“(1/2) 注”部分进行计算。
在本申请中，所述S 凹陷层/S 芯层优选为2～6，更优选为3～5，最优 选为4。
在本申请中，细径光纤的剖面结构中凹陷层面积是芯层面积的2～6倍，能够实现细径光纤的抗弯曲特性。
在本申请中，所述涂覆层的成分优选选自聚氨酯丙烯酸酯、聚硅氧烷丙烯酸酯、环氧丙烯酸酯或聚酯丙烯酸酯。
在本申请中，所述涂覆层的厚度优选为35～45微米，更优选为38～42微米，最优选为40微米。
在本申请中，所述内涂覆层成分优选选自聚氨酯丙烯酸酯、聚硅氧烷丙烯酸酯、环氧丙烯酸酯或聚酯丙烯酸酯，所述内涂覆层的厚度优选为15～30微米，更优选为20～25微米，最优选为23微米；所述外涂覆层的成分优选选自聚氨酯丙烯酸酯、聚硅氧烷丙烯酸酯、环氧丙烯酸酯或聚酯丙烯酸酯，所述外涂覆层的厚度优选为10～25微米，更优选为15～20微米，最优选为17微米。
在本申请中，所述内涂覆层的弹性模量优选为0.5～3MPa，更优选为1～2.5MPa，最优选为1.5～2MPa；外涂覆层的弹性模量优选为1000～2000MPa，更优选为1200～1800MPa，最优选为1400～1600MPa。
在本申请中，所述裸光纤的直径(d)优选为76～90微米，更优选为80～85微米；所述细径光纤的直径(D)优选为155～175微米，更优选为160～170微米，最优选为165微米。
在本申请中，所述细径光纤在管道中的容积优选为：
V＝(D/2)^2*π*L，
其中，D为细径光纤涂覆层外径；
L为光纤的单位长度。
在本申请中，所述细径光纤容积占比为V min/ Vst，V min为细径光纤容积；V st为标准光纤容积。本申请中细径光纤的管道容积占有率是标准光纤(涂覆层外径250微米)的50％，大幅提高管道资源利用率。
本申请提供的细径光纤，模场直径＝8.4～9.2微米，缆波长低于1260nm，零色散波长＝1310～1324m，1310、1550nm波长处衰减分别 低于0.35dB/km、0.25dB/km，弯曲半径R为7.5mm时，1550、1625nm波长处的弯曲损耗分别低于0.3dB、0.5dB；0.5m分别在15％、50％条件下的抗拉强度≥420kpsi、480kpsi。
本申请提供了一种上述技术方案所述的细径光纤的制备方法，包括：
制备得到芯层；
在所述芯层表面制备光学包层；
在所述光学包层表面制备凹陷层，得到芯棒；
将所述芯棒进行高温均匀化处理；
在所述高温均匀化处理后的芯棒表面制备外包层，得到预制棒；
在所述预制棒表面制备涂覆层，得到细径光纤。
本申请对所述芯层的制备方法没有特殊的限制，采用本领域技术人员熟知的芯层制备方法即可，如采用VAD设备进行沉积，喷灯中通入氧气、氢气、四氯化硅、四氯化锗、Ar气体，通过高温反应形成二氧化硅、二氧化锗附着在靶棒端面；沉积结束后进行脱羟和玻璃化烧结，得到芯层，通过对四氯化锗流量的控制形成具有一定相对折射率差的芯层。本申请对所述脱羟和玻璃化烧结的温度没有特殊的限制，本领域技术人员可根据实际情况选择合适的脱羟和玻璃化烧结的温度，优选通过通入氯气进行脱羟处理。
本申请对所述光学包层的制备方法没有特殊的限制，采用本领域技术人员熟知的光学包层的制备方法进行制备即可，如可按照上述技术方案所述芯层的制备方法制备光学包层，先采用VAD设备进行沉积，喷灯中通入氧气、氢气、四氯化硅、Ar气体进行沉积，沉积结束后进行脱羟和玻璃化烧结，玻璃化烧结过程中通入氟化物气体，氟化物气体的流量线性递增直至烧结结束，得到光学包层，通过控制氟化物气体流量的线性递增使光学包层的相对折射率差产生渐变。本领域技术人员可根据实际情况选择控制上述制备过程中的工艺参数以获得所需的光学包层。在本申请中，所述氟化物优选选自SiF 4、CF 4、 SF 6、C 2F 6、SOF 2和C 2F 2Cl 2的一种或至少两种组合。
本申请对所述凹陷层的制备方法没有特殊的限制，采用本领域技术人员熟知的凹陷层的制备方法进行制备即可，如可采用等离子沉积(POD)的方法进行制备，POD喷灯来回喷涂于外包层表面，逐层沉积，喷灯内通入SiCl 4、O 2、氟化物，形成含氟的玻璃层，通过对氟化物流量的控制使凹陷层的相对折射率差产生渐变。本领域技术人员可根据实际情况选择控制上述制备过程中的工艺参数以获得所需的凹陷层。在本申请中，所述氟化物优选选自SiF 4、CF 4、SF 6、C 2F 6、SOF 2和C 2F 2Cl 2的一种或至少两种组合。
在本申请中，制备芯层、光学包层和凹陷层过程中通过控制掺杂物(四氟化锗或氟化物)的流量实现各层中折射率的变化；更优选制备光学包层和凹陷层沉积的过程中，通过控制掺杂物的流量变化来实现折射率的渐变。
在本申请中，所述高温均匀化处理的方法，优选包括：
在2～3h内由室温升温至1250～1500℃后恒温10～20h，真空度保持-0.3～-0.6bar；然后充入N 2使压力保持0.2～0.5bar在1150～1450℃恒温4～6h；
再次抽真空使真空度保持在-0.3～-0.6bar在1250～1500℃恒温12～24h；然后降温至1000℃以下再进行自然冷却。
在本申请的实施例中，所述高温均匀化处理的示意图如图5所示。
本申请采用上述高温均化处理工艺，利用缓慢的高温蠕变与退火特性，可以有效改善预制棒石英玻璃中局部的结构不均匀性及各层边界上的微缺陷与应力，同时，实现边界区域内掺杂扩散，缓解各层边界上因掺杂不同热膨胀系数不同引起的微应力；再者，利用真空+加压+真空方式，来促使石英玻璃中的气泡排移出棒体，消除棒体内的微小气泡。
在本申请中，所述由室温升温的时间优选为2.5小时，升温的温 度优选为1300～1450℃，更优选为1350～1400℃，恒温时间优选为12～18h，更优选为14～16h，真空度优选为-0.4～-0.5bar；充入N 2使压力保持优选为0.3～0.4bar，恒温温度优选为1200～1400℃，更优选为1250～1350℃，最优选为1300℃，恒温时间优选为5h。
在本申请中，所述再次抽真空的真空度优选为-0.4～-0.5bar，恒温温度优选为1300～1450℃，更优选为1350～1400℃，恒温时间优选为16～20h。在本申请中，所述降温的速度优选为2～6℃/min，更优选为3～5℃/min，最优选为4℃/min。
在本申请中，所述外包层的制备方法优选为气相沉积法或在芯棒外面组装套管。本申请对所述气相沉积法或组装套管的方法没有特殊的限制，采用本领域技术人员熟知的上述方法制备外包层即可，如将上述高温处理后的芯棒放置在OVD机台上进行沉积，达到目标重量或棒径后，沉积结束，再进行烧结，得到外包层；或将上述高温处理后的芯棒直接装入二氧化硅套管内组装，得到外包层。
本申请对所述涂覆层的制备方法没有特殊的限制，采用本领域技术人员熟知的涂覆层的制备方法制备得到上述成分及厚度的涂覆层即可。
本申请通过设计预制棒的剖面结构，使其剖面中光学包层渐变式设计，有利于提高光纤的MFD值，使之与标准光纤接近或相等；凹陷层渐变式结构设计，保证光纤宏弯要求的同时，也利于控制光纤的截止波长，满足光纤传输要求。
另外，本申请采用高温均化处理工艺，能够有效改善预制棒石英玻璃中局部的结构不均匀性及各层边界上的微缺陷与应力，缓解各层边界上因掺杂不同热膨胀系数物质引起的微应力；同时，有效消除棒体内的微小气泡。本申请可广泛应用于石英玻璃加工行业。
附图说明
为了更清楚地说明本申请实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍，显而 易见地，下面描述中的附图仅仅是本申请的实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据提供的附图获得其他的附图。
图1为本申请实施例1制备的细径光纤折射率剖面示意图；
图2为本申请实施例2制备的细径光纤折射率剖面示意图；
图3为本申请实施例3制备的细径光纤折射率剖面示意图；
图4为本申请实施例4制备的细径光纤的剖面分布图；
图5为本申请实施例提供的高温处理温度示意图；
图6为本申请提供的细径光纤横截面的结构示意图；
图7为本申请比较例1制备的细径光纤的剖面分布图；
图8为本申请比较例2制备的细径光纤折射率剖面示意图。
具体实施方式
下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
实施例1
采用VAD+OVD工艺，以SiCl 4、GeCl 4、C 2F 6为原料，在制作过程中通过改变气体流量和比例，以及反应区的移动速度和沉积趟数制备出符合光纤预制棒剖面设计要求的芯层、光学包层、凹陷层；其中，制备的粉末棒，在烧结过程中通过氯气进行脱羟处理，最终形成透明玻璃棒。
将上述制备的玻璃棒放置在特定的真空高温室内，进行高温均化处理：2h内，由室温升至1250℃后，恒温20h，炉内真空度保持在-0.3bar；然后，充入N 2使炉内压力保持0.5bar、恒温6h，温度1250℃下运行；二次真空阶段，压力保持在-0.3bar，1250℃，恒温24h；结束后，按2℃/min进行缓慢降温至1000℃后，进行自然冷却。
最后，采用OVD工艺，根据设定的外包重量制备外包层，获得成品预制棒，然后进行两层涂层涂覆，得到细径光纤；拉丝时，细径光纤内涂层的弹性模量在0.5MPa，外涂层的弹性模量在1000MPa。
采用美国Interfiber公司提供的IFA-100型号的光纤折射率测试仪，测试本申请实施例1制备的细径光纤的折射率剖面数据(其折射率剖面示意图如图1所示)，检测结果如表1所示(△n1为芯层相对折射率差，△n2为光学包层相对折射率差，△n3为凹陷层相对折射率差，r1为芯层半径，r2为光学包层半径，r3为凹陷层半径，r4为外包层半径，d为裸光纤(不含图涂覆层)直径，D为细径光纤直径)。
采用美国PK公司的OTDR、PK2200、色散仪，测试本申请实施例1制备的细径光纤的光学性能；采用两点弯曲法(按照GB/T15972.31-2008《光纤试验方法规范第31部分：机械性能的测量方法和试验程序—抗张强度》标准方法)，测试本申请实施例1制备的细径光纤的力学性能，检测结果如表2所示。
实施例2
采用VAD+OVD工艺，以SiCl 4、GeCl 4、SiF 4为原料，在制作过程中通过改变气体流量和比例，以及反应区的移动速度和沉积趟数制备出符合光纤预制棒剖面设计要求的芯层、光学包层、凹陷层；其中，制备的粉末棒，在烧结过程中通过氯气进行脱羟处理，最终形成透明玻璃棒。
将上述制备的玻璃棒放置特定的真空高温室内，进行高温均化处理：3h内，由室温升至1500℃后，恒温10h，炉内真空度保持在-0.6bar；然后，充入N 2使炉内压力保持0.5bar、恒温4h，温度1400℃下运行；二次真空阶段，压力保持在-0.6bar，1350℃，恒温24h；结束后，按4℃/min进行缓慢降温至1000℃后，进行自然冷却。
最后，采用OVD工艺，根据设定的外包重量制备外包层，获得预制棒，然后涂覆两层涂层，得到细径光纤。拉丝时，细径光纤内涂层的弹性模量在0.5MPa，外涂层的弹性模量在2000MPa。
按照实施例1的方法，测试本申请实施例2制备的细径光纤的折射率剖面数据(其折射率剖面示意图如图2所示)，检测结果如表1所示。
按照实施例1的方法，测试本申请实施例2制备的细径光纤的光学性能和力学性能，检测结果如表2所示。
实施例3
采用MCVD工艺，以SiCl 4、GeCl 4、SF 6、Cl 2为原料，在制作过程中通过改变气体流量和比例，以及反应区的移动速度和沉积趟数制备出符合光纤预制棒剖面设计要求的芯层、光学包层、凹陷层，通过收缩形成透明玻璃棒。
将上述制备的玻璃棒放置特定的真空高温室内，进行高温均化处理：3h内，由室温升至1350℃后，恒温15h，炉内真空度保持在-0.5bar；然后，充入N 2使炉内压力保持0.4bar、恒温6h，温度1350℃下运行；二次真空阶段，压力保持在-0.5bar，1250℃，恒温15h；结束后，按6℃/min进行缓慢降温至1000℃后，进行自然冷却。
最后，采用石英套管匹配，组装获得预制棒，涂覆两层涂层，得到细径光纤。拉丝时，细径光纤内涂层的弹性模量在3MPa，外涂层的弹性模量在2000MPa。
按照实施例1的方法，测试本申请实施例3制备的细径光纤的折射率剖面数据(其折射率剖面示意图如图3所示)，检测结果如表1所示。
按照实施例1的方法，测试本申请实施例3制备的细径光纤的光学性能和力学性能，检测结果如表2所示。
实施例4
采用OVD工艺，以SiCl 4、GeCl 4、SiF 4为原料，在制作过程中通过改变气体流量和比例，以及反应区的移动速度和沉积趟数制备出符合光纤预制棒剖面设计要求的芯层、光学包层、凹陷层；其中，制备的粉末棒，在烧结过程中通过氯气进行脱羟处理，最终形成透明玻 璃棒。
将上述制备的玻璃棒放置特定的真空高温室内，进行高温均化处理：3h内，由室温升至1350℃后，恒温20h，炉内真空度保持在-0.5bar；然后，充入N 2使炉内压力保持0.2bar、恒温4h，温度1350℃下运行；二次真空阶段，压力保持在-0.3bar，1350℃，恒温24h；结束后，按4℃/min进行缓慢降温至1000℃后，进行自然冷却。
最后，采用石英套管匹配，组装获得预制棒，涂覆两层涂层，得到细径光纤。拉丝时，细径光纤内涂层的弹性模量在1.5MPa，外涂层的弹性模量在1500MPa。
采用美国Interfiber公司提供的IFA-100型号的光纤折射率测试仪检测实施例4制备的细径光纤剖面分布，检测结果如图4所示，从图形看边界处连接顺畅，无可见缺陷。
按照实施例1的方法，测试本申请实施例4制备的细径光纤的折射率剖面数据，检测结果如表1所示。
按照实施例1的方法，测试本申请实施例4制备的细径光纤的光学性能和力学性能，检测结果如表2所示。
比较例1
采用OVD工艺，以SiCl 4、GeCl 4、SiF 4为原料，在制作过程中通过改变气体流量和比例，以及反应区的移动速度和沉积趟数制备出符合光纤预制棒剖面设计要求的芯层、光学包层、凹陷层；其中，制备的粉末棒，在烧结过程中通过氯气进行脱羟处理，最终形成透明玻璃棒。
将上述制备的玻璃棒采用石英套管匹配，组装获得预制棒，涂覆两层涂层，得到光纤。拉丝时，光纤内涂层的弹性模量在1.5MPa，外涂层的弹性模量在1500MPa。
按照实施例4的方法检测本申请比较例1制备的光纤的剖面分布，检测结果如图7所示，从图形看边界处存在缺陷。
按照实施例1的方法，测试本申请比较例1制备的细径光纤的折 射率剖面数据，检测结果如表1所示。
按照实施例1的方法，测试本申请比较例1制备的细径光纤的光学性能和力学性能，检测结果如表2所示。
比较例2
采用VAD+OVD工艺，以SiCl 4、GeCl 4、SiF 4为原料，在制作过程中通过改变气体流量和比例，以及反应区的移动速度和沉积趟数制备出符合光纤预制棒剖面设计要求的芯层、光学包层、凹陷层；其中，制备的粉末棒，在烧结过程中通过氯气进行脱羟处理，最终形成透明玻璃棒。
将上述制备的玻璃棒，采用OVD工艺，根据设定的外包重量制备外包层，获得预制棒，涂覆两层涂层，得到光纤。拉丝时，光纤内涂层的弹性模量在0.5MPa，外涂层的弹性模量在2000MPa。
按照实施例1的方法，测试本申请比较例2制备的细径光纤的折射率剖面数据(其折射率剖面示意图如图8所示)，检测结果如表1所示。
按照实施例1的方法，测试本申请比较例2制备的细径光纤的光学性能和力学性能，检测结果如表2所示。
表1 本申请实施例和比较例制备的光纤折射率剖面数据
Figure PCTCN2020142343-appb-000001
表2 本申请实施例和比较例制备的光纤的性能数据
Figure PCTCN2020142343-appb-000002
Figure PCTCN2020142343-appb-000003
从表1和表2可以看出，采用折射率渐变的光学包层更有利于提高MFD(模场直径)值；凹陷层渐变设计的光纤，在保证宏弯的同时，其缆波长可略低于非渐变折射率剖面光纤的缆波长。同时，通过高温均化处理后，光纤的抗拉强度优于非高温处理的光纤强度。
由以上实施例可知，本申请提供了一种细径光纤，包括：裸光纤；包覆在所述裸光纤外层的涂覆层；所述裸光纤包括：芯层；包覆在所述芯层表面的光学包层；包覆在所述光学包层表面的凹陷层；包覆在所述凹陷层表面的外包层；所述光学包层的相对折射率差从内向外渐变，渐变范围为+0.05～-0.10％。本申请通过设计预制棒的剖面结构，使其剖面中光学包层渐变式设计，有利于提高光纤的MFD值，使之与标准光纤接近或相等；进一步的，凹陷层渐变式结构设计，保证光纤宏弯要求的同时，也利于控制光纤的截止波长，满足光纤传输要求。

Claims (10)

  1. 一种细径光纤，包括：
    裸光纤；
    包覆在所述裸光纤外层的涂覆层；
    所述裸光纤包括：
    芯层；
    包覆在所述芯层表面的光学包层；
    包覆在所述光学包层表面的凹陷层；
    包覆在所述凹陷层表面的外包层；
    所述光学包层的相对折射率差从内向外渐变，渐变范围为+0.05～-0.10％。
  2. 根据权利要求1所述的细径光纤，其特征在于，所述凹陷层的相对折射率差从内向外渐变，渐变范围为-0.6～0％。
  3. 根据权利要求1所述的细径光纤，其特征在于，所述芯层的相对折射率差为0.3～0.35％。
  4. 根据权利要求1所述的细径光纤，其特征在于，所述芯层的半径为3～5微米。
  5. 根据权利要求1所述的细径光纤，其特征在于，所述光学包层的厚度为5～20微米。
  6. 根据权利要求1所述的细径光纤，其特征在于，所述凹陷层的厚度为5～15微米。
  7. 根据权利要求1所述的细径光纤，其特征在于，所述外包层的相对折射率差为0。
  8. 根据权利要求1所述的细径光纤，其特征在于，所述凹陷层区域面积与芯层区域面积的比值为2～6。
  9. 一种权利要求1所述的细径光纤的制备方法，包括：
    制备得到芯层；
    在所述芯层表面制备光学包层；
    在所述光学包层表面制备凹陷层，得到芯棒；
    将所述芯棒进行高温均匀化处理；
    在所述高温均匀化处理后的芯棒表面制备外包层，得到预制棒；
    在所述预制棒表面制备涂覆层，得到细径光纤。
  10. 根据权利要求9所述的方法，其特征在于，所述高温均匀化处理的方法，包括：
    在2～3h内由室温升温至1250～1500℃后恒温10～20h，真空度保持-0.3～-0.6bar；然后充入N 2使压力保持0.2～0.5bar在1150～1450℃恒温4～6h；
    再次抽真空使真空度保持-0.3～-0.6bar，在1250～1500℃恒温12～24h；然后降温至1000℃以下再进行自然冷却。
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113625390A (zh) * 2021-10-14 2021-11-09 长飞光纤光缆股份有限公司 一种色散优化弯曲不敏感光纤
CN116589174A (zh) * 2023-05-09 2023-08-15 中天科技光纤有限公司 石英预制件、光纤及光纤制备方法

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111323872B (zh) * 2020-02-18 2022-09-06 中天科技精密材料有限公司 一种细径光纤及其制备方法
NL2026285B1 (en) * 2020-07-07 2022-03-11 Corning Inc Optical fiber with inverse triangular trench design
WO2022010667A1 (en) * 2020-07-07 2022-01-13 Corning Incorporated Optical fiber with inverse triangular trench design
CN113698092B (zh) * 2020-12-14 2022-12-16 深圳纤亿通科技有限公司 一种光纤及其制备方法
CN113292241B (zh) * 2021-05-26 2024-05-14 中天科技光纤有限公司 光纤拉丝炉、光纤制备装置、光纤制备方法及细径光纤
CN114236674A (zh) * 2021-12-27 2022-03-25 江苏亨通光纤科技有限公司 一种超高强度细直径抗弯曲光纤
CN114349327A (zh) * 2022-01-18 2022-04-15 江苏亨通光导新材料有限公司 一种弯曲不敏感单模光纤的低成本加工工艺
CN115417593A (zh) * 2022-09-20 2022-12-02 中天科技光纤有限公司 光纤预制棒、光纤拉丝装置以及光纤拉丝方法
CN115490419B (zh) * 2022-09-30 2023-10-17 中天科技光纤有限公司 光纤及其制备方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007298885A (ja) * 2006-05-02 2007-11-15 Hitachi Cable Ltd 分散補償光ファイバ
CN101770051A (zh) * 2008-12-19 2010-07-07 三星光通信株式会社 低弯曲损耗光纤
CN109081575A (zh) * 2017-06-14 2018-12-25 中天科技精密材料有限公司 光纤预制棒及其制造方法
KR20190057939A (ko) * 2017-11-21 2019-05-29 한국광기술원 낮은 굽힘손실을 갖는 광섬유
CN110045456A (zh) * 2019-03-01 2019-07-23 江苏永鼎股份有限公司 一种超低损耗大有效面积的单模光纤及其制备方法
CN110794509A (zh) * 2019-09-29 2020-02-14 法尔胜泓昇集团有限公司 一种单模光纤及其制备方法
CN111323872A (zh) * 2020-02-18 2020-06-23 中天科技精密材料有限公司 一种细径光纤及其制备方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4127868C2 (de) * 1991-08-22 1994-11-10 Rheydt Kabelwerk Ag Einmoden-Faser mit rampenförmigem Brechzahl-Profil
US6717721B2 (en) * 2001-12-21 2004-04-06 Corning Incorporated Large effective area erbium doped fiber optical amplifier
US8666214B2 (en) * 2011-11-30 2014-03-04 Corning Incorporated Low bend loss optical fiber
US9110220B2 (en) * 2013-07-16 2015-08-18 Corning Incorporated High bandwidth MMF and method of making
CN106517759B (zh) * 2016-10-18 2019-06-21 中国科学院上海光学精密机械研究所 稀土掺杂石英玻璃棒的均化制备方法

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007298885A (ja) * 2006-05-02 2007-11-15 Hitachi Cable Ltd 分散補償光ファイバ
CN101770051A (zh) * 2008-12-19 2010-07-07 三星光通信株式会社 低弯曲损耗光纤
CN109081575A (zh) * 2017-06-14 2018-12-25 中天科技精密材料有限公司 光纤预制棒及其制造方法
KR20190057939A (ko) * 2017-11-21 2019-05-29 한국광기술원 낮은 굽힘손실을 갖는 광섬유
CN110045456A (zh) * 2019-03-01 2019-07-23 江苏永鼎股份有限公司 一种超低损耗大有效面积的单模光纤及其制备方法
CN110794509A (zh) * 2019-09-29 2020-02-14 法尔胜泓昇集团有限公司 一种单模光纤及其制备方法
CN111323872A (zh) * 2020-02-18 2020-06-23 中天科技精密材料有限公司 一种细径光纤及其制备方法

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113625390A (zh) * 2021-10-14 2021-11-09 长飞光纤光缆股份有限公司 一种色散优化弯曲不敏感光纤
CN113625390B (zh) * 2021-10-14 2021-12-31 长飞光纤光缆股份有限公司 一种色散优化弯曲不敏感光纤
CN116589174A (zh) * 2023-05-09 2023-08-15 中天科技光纤有限公司 石英预制件、光纤及光纤制备方法

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