CN114966949A - Metal/dielectric terahertz hollow fiber and continuous preparation method and device thereof - Google Patents

Metal/dielectric terahertz hollow fiber and continuous preparation method and device thereof Download PDF

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Publication number
CN114966949A
CN114966949A CN202210380807.7A CN202210380807A CN114966949A CN 114966949 A CN114966949 A CN 114966949A CN 202210380807 A CN202210380807 A CN 202210380807A CN 114966949 A CN114966949 A CN 114966949A
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metal
medium
optical fiber
resin
coating
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Chinese (zh)
Inventor
敬承斌
刘晟
程浩淼
余烁颖
鲁学会
赵强
褚君浩
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East China Normal University
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East China Normal University
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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
    • G02B6/02295—Microstructured optical fibre
    • G02B6/023—Microstructured optical fibre having different index layers arranged around the core for guiding light by reflection, i.e. 1D crystal, e.g. omniguide
    • G02B6/02304—Core having lower refractive index than cladding, e.g. air filled, hollow core
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • 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
    • G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
    • G02B6/4401—Optical cables
    • G02B6/4429—Means specially adapted for strengthening or protecting the cables
    • G02B6/443—Protective covering
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P11/00—Apparatus or processes specially adapted for manufacturing waveguides or resonators, lines, or other devices of the waveguide type
    • H01P11/001—Manufacturing waveguides or transmission lines of the waveguide type
    • H01P11/002—Manufacturing hollow waveguides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P3/00—Waveguides; Transmission lines of the waveguide type
    • H01P3/12—Hollow waveguides
    • H01P3/127—Hollow waveguides with a circular, elliptic, or parabolic cross-section

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  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Manufacturing & Machinery (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)

Abstract

The invention discloses a metal/medium terahertz hollow optical fiber and a continuous preparation method and a device thereof, and is characterized in that the method comprises the steps of pretreating a medium tube, depositing a metal coating on the outer surface of the medium tube, coating protective layer resin on the outer surface of the metal coating, finishing rolling and the like, and a metal high-reflection film can be deposited and grown on the outer surface of the medium tube with continuous length, so that the large-scale preparation of metal/medium terahertz hollow waveguides is realized. Compared with the prior art, the method has the advantages of good bending performance, low transmission loss, simple process and the like, effectively enhances the bonding performance between the dielectric layer and the metal layer, improves the weather resistance and the transmission effect of the optical fiber, realizes large-scale continuous preparation of the metal/dielectric terahertz hollow optical fiber with unlimited length, effectively improves the production efficiency, reduces the production cost, enlarges the application range of the metal/dielectric terahertz hollow optical fiber, and has a wide application prospect.

Description

Metal/dielectric terahertz hollow fiber and continuous preparation method and device thereof
Technical Field
The invention relates to the technical field of optical fiber preparation, in particular to a metal/medium terahertz hollow optical fiber and a continuous preparation method and a continuous preparation device thereof.
Background
With the rapid development of terahertz technology, the application requirements of terahertz technology in the fields of imaging, detection, sensing, communication and the like are increasing day by day, the transmission of terahertz waves is an important link in terahertz technology, and the terahertz wave transmission is widely concerned, so that the development of high-reliability optical fibers for terahertz wave transmission is greatly necessary. To date, researchers have developed a variety of terahertz optical fibers including hollow-core metal waveguides, dielectric tube waveguides, photonic crystal fibers, and metal/dielectric hollow-core fibers. Among them, the metal/dielectric terahertz hollow optical fiber has the excellent characteristics of simple structure, no end surface reflection, adjustable low-loss transmission window and the like, and has received great attention. The traditional preparation of metal/medium hollow optical fiber is that reaction liquid is introduced into a fixed capillary structure tube, and a metal reflecting film is deposited on the inner surface of the tube, and the thickness of the film has gradient change (non-uniformity) to a certain extent along the length direction of the capillary tube, which becomes one of the factors limiting the development length of the optical fiber.
At present, a plurality of documents report that the metal/medium hollow-core optical fiber is prepared by using a chemical liquid deposition method, but the transmission performance of the optical fiber is limited to a certain extent due to the poor combination effect between the medium layer and the metal layer. The plasma is used for processing the outer surface of the medium tube, so that the bonding performance between the metal layer and the medium layer can be effectively enhanced, and the weather resistance and the transmission effect of the optical fiber are improved. However, none of the published reports disclose a method and apparatus for making metal/dielectric hollow-core optical fibers that can be mass produced in a continuous manner in unlimited lengths. The preparation cost of the existing metal/medium hollow optical fiber is high, the production efficiency is extremely low, and meanwhile, the length of the optical fiber also limits the prospect of large-scale application.
Disclosure of Invention
The invention aims to design a metal/medium terahertz hollow optical fiber and a continuous preparation method and a device thereof aiming at the defects of the prior art, a medium pipe with the inner diameter of 1-10 mm is adopted as a medium layer of the hollow optical fiber, a metal coating and a resin protective layer are sequentially arranged on the outer surface of the medium pipe to form the metal/medium terahertz hollow optical fiber, a metal coating is deposited on the outer surface of the medium pipe, the protective layer resin is coated on the outer surface of the metal coating, and the winding is completed, so that a metal high-reflection film is deposited and grown on the outer surface of the medium pipe with continuous length, the production device for continuously preparing the metal/medium terahertz hollow waveguide on a large scale can realize continuous production without limitation on length, has the advantages of simple process, low production cost, high production efficiency, good bending performance, low transmission loss and the like, better solves the problem of poor bonding performance between the medium layer and the metal layer, and is difficult to realize large-scale continuous production, and has wide application prospect.
The purpose of the invention is realized as follows: a metal/medium terahertz hollow-core optical fiber is characterized in that a medium pipe with the inner diameter of 1-10 mm is used as a medium layer of the hollow-core optical fiber, a metal coating and a resin protective layer are sequentially arranged on the outer surface of the medium pipe to form the metal/medium terahertz hollow-core optical fiber, and the medium layer is low-absorption-rate terahertz polypropylene, polytetrafluoroethylene, polypropylene ethylene or cyclic olefin copolymer; the metal coating is made of a terahertz wave high-reflectivity metal material of silver, copper or gold; the resin protective layer is made of silicon rubber resin or acrylic resin; the thickness of the dielectric layer is 10-500 mu m; the thickness of the metal coating is 100-2000 nm; the thickness of the resin protective layer is 100-2000 mu m.
A continuous preparation method of a metal/medium terahertz hollow-core optical fiber is characterized by comprising the following steps:
a, step a: cleaning and drying the medium pipe with continuous length and pretreating with plasma gas, and sealing two ends of the pretreated medium pipe with sealing materials;
b, step (b): continuously passing the pretreated medium pipe through a dynamic liquid phase chemical deposition reaction zone, and depositing a metal coating on the surface of the medium pipe;
c, step (c): introducing the medium pipe plated with the metal layer into a drying area, uniformly coating adhesive resin glue solution on the outer surface of the metal coating after drying, and curing to obtain a resin protective layer;
d, step: and removing the seals at the two ends of the medium pipe and rolling to finish the preparation of the metal/medium terahertz hollow optical fiber.
The medium pipe is a polypropylene, polytetrafluoroethylene, polypropylene ethylene or cycloolefin copolymer pipe with the inner diameter of 1-10 mm, and the wall thickness of the medium pipe is 10-500 mu m; the metal coating is made of silver, copper or gold metal materials, and the thickness of the coating is 100-2000 nm; the resin protective layer is made of silicone rubber resin or acrylic resin, and the thickness of the protective layer is 100-2000 mu m; the plasma gas is hydrogen, oxygen, argon or nitrogen.
A continuous preparation device of a metal/medium terahertz hollow optical fiber is characterized in that a liquid phase deposition metal reaction unit, a resin coating unit and a wire spool are adopted to form the continuous preparation device of the metal/medium terahertz hollow optical fiber, a pretreated medium pipe sequentially enters the liquid phase deposition metal reaction unit and the resin coating unit through a guide wheel to deposit a metal coating and coat the resin of a protective layer, and the liquid phase deposition metal reaction unit comprises: a deposition reaction cavity, a drying area, a peristaltic pump and reaction liquid; the resin coating unit includes: a resin coating cavity and a resin curing area; the medium pipe is sent into the liquid phase deposition metal reaction unit by the guide wheel, metal particles are deposited on the surface of the medium pipe in the deposition reaction cavity and the liquid phase deposition solution sent into the reaction cavity by the peristaltic pump, and after a metal coating is formed, the medium pipe is sent into a drying area for hot air drying; the resin coating unit is used for uniformly coating the resin glue solution on the surface of the metal coating in the resin coating cavity by the fed medium tube to form a resin protective layer and then feeding the resin protective layer into a resin curing area, wherein the cured medium tube is a metal/medium terahertz hollow optical fiber and is wound by a winding disc, so that the continuous production of the metal/medium terahertz hollow optical fiber with unlimited length is realized.
Compared with the prior art, the method has the advantages of good bending performance, low transmission loss, simple process, long continuous production length and the like, effectively enhances the bonding performance between the dielectric layer and the metal layer by performing plasma treatment on the dielectric tube, improves the weather resistance and the transmission effect of the optical fiber, can realize large-scale continuous preparation of the metal/dielectric terahertz hollow optical fiber with unlimited length, effectively improves the production efficiency, reduces the production cost, further increases the application range of the metal/dielectric terahertz hollow optical fiber, and has a wide application prospect.
Drawings
FIG. 1 is a schematic diagram of a metal/dielectric terahertz hollow core optical structure;
FIG. 2 is a process flow diagram of a method for manufacturing a metal/medium terahertz hollow-core optical fiber;
FIG. 3 is a schematic diagram of a device for manufacturing a metal/dielectric terahertz hollow-core optical fiber.
Detailed Description
Referring to fig. 1, a medium tube with an inner diameter of 1-10 mm is used as a medium layer 110 of a hollow-core optical fiber, a metal plating layer 120 and a resin protection layer 130 are sequentially arranged on the outer surface of the medium tube to form a metal/medium terahertz hollow-core optical fiber, and the medium tube 110 is a terahertz low-absorption polypropylene, polytetrafluoroethylene, polypropylene or cyclic olefin copolymer tube; the metal plating layer 120 is made of a terahertz-wave high-reflectivity metal material of silver, copper or gold; the resin protection layer 130 is silicon rubber or acrylic resin.
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Referring to fig. 2, the continuous preparation of the metal/dielectric terahertz hollow-core optical fiber of the invention specifically comprises the following steps:
s1: and (3) pretreating the outer surface of the medium pipe, including cleaning, drying and plasma treatment.
In the step, the inner diameter of the preferred medium pipe is 1-10 mm, the thickness of the medium layer is 100-500 μm, the gas used in the plasma treatment includes, but is not limited to, hydrogen, oxygen, argon and nitrogen, and the plasma treatment time is 3-30 min.
S2: and preparing a metal coating on the outer surface of the medium tube by adopting a chemical liquid phase deposition method and drying.
In the step, reaction liquid is introduced into the reaction cavity by using a peristaltic pump, and the reaction liquid reacts in the reaction cavity to generate metal atoms which are deposited on the outer surface of the medium pipe to form a metal coating; the reaction waste liquid is discharged from the lower end of the cavity, and the medium pipe deposited with the metal layer enters the drying area through the lower end of the cavity; and drying the sample in a drying area by heating, ventilating and the like.
S3: and coating a resin protective layer on the outer surface of the metal coating, and curing and drying.
In the step, a medium pipe with a metal layer deposited on the surface is dried and then enters a protective layer resin coating cavity, and a sample with the protective layer resin coated on the surface enters a protective layer resin curing area through the lower end of the cavity; and the curing area is used for curing and drying the sample in modes of ultraviolet curing, heating, ventilation and the like.
S4: and rolling and finishing the preparation of the metal/medium terahertz hollow optical fiber.
Referring to fig. 3, the continuous preparation device of the metal/dielectric terahertz hollow-core optical fiber of the invention comprises: a liquid-phase deposition metal reaction unit 310, a protective layer resin coating unit 320, and a wire spool 330; the pretreated medium tube 350 passes through the guide wheel 340 and then enters the liquid phase deposition metal reaction unit 310, the medium tube 350 deposits a metal coating on the surface and then enters the protective layer resin coating unit 320 after drying, and the protective layer resin is coated successfully and then wound by the wire spool 330 after being cured, so that the preparation of the metal/medium terahertz hollow optical fiber is completed.
The liquid phase deposition metal reaction unit 310 includes: a deposition reaction cavity 311, a drying area 312, a peristaltic pump 313 and a reaction liquid 314; the peristaltic pump 313 pumps the reaction liquid 314 into the deposition reaction cavity 311, and the outer surface of the medium pipe 350 deposits a metal coating in the deposition reaction cavity 311 and is dried by the drying area 312.
The protective layer resin coating unit 320 includes: a resin coating cavity 321 and a resin curing zone 322; the dried medium pipe 350 with the metal layer plated on the surface enters the resin coating cavity 321, the protective layer resin glue solution is uniformly coated on the surface of the metal layer, and then the medium pipe enters the resin curing area 322 for curing and drying.
The action mechanism and the advantages of the metal/medium terahertz hollow-core optical fiber are as follows: the outer surface of the medium tube is treated by the plasma, so that the bonding performance between the medium layer and the metal layer is greatly improved, and the performance of the optical fiber is enhanced. In addition, aiming at the structure of the metal/medium terahertz hollow optical fiber, the traditional preparation method and the preparation system are that reaction liquid is introduced into a capillary structure tube in a fixed state to deposit a metal reflecting film on the inner surface of the capillary structure tube, and the film thickness of the metal reflecting film is changed (uneven) along the length direction of the capillary tube in a certain degree of gradient, so that the metal/medium terahertz hollow optical fiber becomes one of the factors for limiting the development length of the optical fiber.
The above-described embodiments are merely illustrative of the best mode of carrying out the invention, and the description is in detail and specific, but not construed as limiting the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (8)

1. A metal/medium terahertz hollow-core optical fiber is characterized in that a medium tube with the inner diameter of 1-10 mm is used as a medium layer of the hollow-core optical fiber, a metal coating and a resin protective layer are sequentially arranged on the outer surface of the medium tube to form the metal/medium terahertz hollow-core optical fiber, and the medium tube is a polypropylene, polytetrafluoroethylene, polypropylene ethylene or cyclic olefin copolymer tube with low terahertz absorption rate; the metal coating is made of a terahertz wave high-reflectivity metal material of silver, copper or gold; the resin protective layer is made of silicon rubber or acrylic resin.
2. A continuous preparation method of the metal/medium terahertz hollow-core optical fiber disclosed by claim 1 is characterized by comprising the following steps of:
a, step: cleaning and drying a continuous length of medium tube and pretreating with plasma gas
b, step (b): continuously passing the pretreated medium pipe through a dynamic liquid phase chemical deposition reaction zone, and depositing a metal coating on the surface of the medium pipe;
c, step (c): introducing the medium pipe plated with the metal layer into a drying area, uniformly coating adhesive resin glue solution on the outer surface of the metal coating after drying, and curing to obtain a resin protective layer;
d, step: and removing seals at two ends of the medium tube and rolling to finish the preparation of the metal/medium terahertz hollow optical fiber.
3. The continuous preparation method of the metal/medium terahertz hollow-core optical fiber according to claim 2, wherein the medium tube is a polypropylene, polytetrafluoroethylene, polystyrene or cyclic olefin copolymer tube with an inner diameter of 1-10 mm, and the wall thickness of the medium tube is 10-500 μm.
4. The continuous preparation method of the metal/medium terahertz hollow-core optical fiber according to claim 2, characterized in that the thickness of the metal coating is 100-2000 nm; the thickness of the resin protective layer is 100-2000 mu m.
5. The continuous preparation method of the metal/dielectric terahertz hollow-core optical fiber according to claim 2, wherein the plasma gas is hydrogen, oxygen, argon or nitrogen.
6. A continuous preparation device of a metal/medium terahertz hollow-core optical fiber as claimed in claim 1, characterized in that the device is composed of a liquid phase deposition metal reaction unit, a resin coating unit and a wire spool, a pretreated medium pipe sequentially enters the liquid phase deposition metal reaction unit and the resin coating unit through a guide wheel to perform deposition of a metal coating and resin coating of a protective layer, the liquid phase deposition metal reaction unit comprises: a deposition reaction cavity, a drying area, a peristaltic pump and reaction liquid; the resin coating unit includes: a resin coating cavity and a resin curing area; the medium pipe is conveyed into the liquid phase deposition metal reaction unit by the guide wheel, and metal particles are deposited on the surface of the medium pipe in the deposition reaction cavity together with the liquid phase deposition solution conveyed into the reaction cavity by the peristaltic pump to form a metal coating and then conveyed into a drying area for hot air drying; the resin coating unit is used for uniformly coating the resin glue solution on the surface of the metal coating in the resin coating cavity by the fed medium tube to form a resin protective layer and then feeding the resin protective layer into a resin curing area, and the cured medium tube is wound into the metal/medium terahertz hollow optical fiber by a wire spool, so that the continuous production of the metal/medium terahertz hollow optical fiber with unlimited length is realized.
7. The continuous manufacturing device of the metal/dielectric terahertz hollow-core optical fiber according to claim 6, wherein the drying zone comprises a heating device and a ventilation device, and the resin curing zone comprises an ultraviolet curing device, a heating device and a ventilation device.
8. The continuous preparation device of the metal/medium terahertz hollow-core optical fiber according to claim 6, wherein the contact areas of the deposition reaction cavity and the resin coating cavity with the medium tube are provided with elastic pressure buffering liners.
CN202210380807.7A 2022-04-12 2022-04-12 Metal/dielectric terahertz hollow fiber and continuous preparation method and device thereof Pending CN114966949A (en)

Priority Applications (1)

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CN202210380807.7A CN114966949A (en) 2022-04-12 2022-04-12 Metal/dielectric terahertz hollow fiber and continuous preparation method and device thereof

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Application Number Priority Date Filing Date Title
CN202210380807.7A CN114966949A (en) 2022-04-12 2022-04-12 Metal/dielectric terahertz hollow fiber and continuous preparation method and device thereof

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CN114966949A true CN114966949A (en) 2022-08-30

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