CN1197798C - Method for producing fibre-optical precast stick - Google Patents
Method for producing fibre-optical precast stick Download PDFInfo
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- CN1197798C CN1197798C CN 02138036 CN02138036A CN1197798C CN 1197798 C CN1197798 C CN 1197798C CN 02138036 CN02138036 CN 02138036 CN 02138036 A CN02138036 A CN 02138036A CN 1197798 C CN1197798 C CN 1197798C
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- Prior art keywords
- density
- sio
- plug
- optical fiber
- high temperature
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- 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]
- C03B37/01413—Reactant delivery systems
-
- 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
- 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]
- C03B37/0148—Means for heating preforms during or immediately prior to deposition
-
- 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
- C03B37/01807—Reactant delivery systems, e.g. reactant deposition burners
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/20—Doped silica-based glasses doped with non-metals other than boron or fluorine
- C03B2201/28—Doped silica-based glasses doped with non-metals other than boron or fluorine doped with phosphorus
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/30—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi
- C03B2201/31—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi doped with germanium
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
Abstract
The present invention relates to a method for manufacturing an optical fiber prefabricated rod, which comprises the following steps that in the internal vapor phase deposition method, a coating layer and a core layer deposit in a pure quartz tube firstly; quartz glass with the deposited core layer is melt and shrunk into a solid core rod at the high temperature of 2100 to 2300 DEG C; oxyhydrogen flame with the high temperature of 2000 to 2100DEG. C is used for carrying out surface polishing to the solid core rod; in the external vapor phase deposition method, a fundamentally uniform quartz material is coated outside the core rod to form a prefabricated rod of a loose body; the loose body is slowly heated at high temperature and is sintered into a large-sized transparent optical fiber prefabricated rod. The refractivity of an outer coating layer is close to that of the pure quartz tube. The method of the present invention combines the internal method and the external method and provides practical technological conditions. The preparation cost of the present invention is 60% lower than that of the sleeve pipe method. The present invention can be used for producing a single mold optical fiber prefabricated rod which can be used for drawing a single mold optical fiber conforming to the quality standard.
Description
One, technical field
The present invention relates to a kind of preparation method who is used as preform, promptly adopt the chemical vapor deposition method and OVD (the Outside Vapor Deposition) outside vapor deposition of MCVD (Modified ChemicalVapor Deposition) improvement, make the method for single-mode fiber prefabricated rods.
Two, background technology
Preform is a mother metal of producing optical fiber, and the optical parametric of optical fiber and geometric parameter all are closely related with each parameter of mother metal.The method of at present popular production preform is promptly produced the plug of optical fiber earlier, the method for producing covering then outside two-step approach.
The method of producing plug can be divided into internal law and outside method by the process characteristic branch.Internal law has the chemical vapor deposition method (MCVD) of plasma chemical vapor deposition method (PCVD) and improvement; Outside method has VAD (VAD) and outside vapour phase chemical deposition (OVD).Internal law is controlled well to the precision of prefabricated rods waveguiding structure, and the optical fiber that the suitable for making variations in refractive index is comparatively complicated is as G655; Outside method is relatively poor to the precision control of prefabricated rods waveguiding structure, but production cost is low, sedimentation effect is high.
The method of producing surrounding layer has outside vapour deposition process (OVD), VAD (VAD), plasma spraying (Plasma Spray), tiretube process (Rod-In-Tube), sol-gel method methods such as (Sol-Gel).
Above-mentioned two kinds of methods respectively have its characteristics, but two kinds of methods are combined the cooperation that needs processing condition, have had not yet to see ripe available reported in literature.
Three, summary of the invention
The present invention seeks to: relate in one aspect to a kind of method of making preform.This method is made plug in conjunction with the advantage of MCVD method and two kinds of technologies of OVD method with the MCVD legal system, and the optical fibre refractivity control of production accurately, moisture is low, loss is little; The object of the invention also is: the method for the lower manufacturing preform of a kind of preparation cost is provided, and the single-mode fiber of the production length of using.Certainly the object of the invention also comprises the method for the Er-doped fiber prefabricated rods that a kind of preparation cost is lower.
The objective of the invention is to realize with following method:
The preparation method of preform comprises the following steps:
A) with inner vapour deposition method earlier at pure silica tube interior from inwall to center deposition covering and sandwich layer,
B) silica glass that will deposit sandwich layer molten solid plug that shortens under 2100-2300 ℃ of high temperature;
C) with 2000-2100 ℃ high temperature oxyhydrogen flame the solid plug is carried out surface finish;
D) coat basic quartz material uniformly in the outside of plug with outer vapour deposition method, form loose body prefabricated rods;
E) this loose body is carried out heat slowly, sinter transparent large prefabricated optical fiber bar into, the specific refractory power of surrounding layer is near the specific refractory power of pure silica tube.
Above-mentioned plug making method adopts the high temperature oxyhydrogen flame, and the chemical vapor deposition method so that the MCVD method promptly improves also can adopt the plasma chemical vapor deposition method.Above-mentioned the molten solid plug that shortens into is carried out the thermal-flame polishing, the thermal source that is adopted is that hydrogen-oxygen flame blowtorch or high frequency plasma flame are as thermal source.Above-mentioned outside chemical vapor deposition method is the OVD method of raw material for adopting with the silicon tetrachloride.In the above-mentioned depositing operation, sedimentary at first one deck or which floor have the density of a SiO2 during external sediment, and all the other each layers have the density of the 2nd SiO2, and the concentration of a SiO2 will be significantly higher than the density of the 2nd SiO2.
Characteristics of the present invention are: internal law and two kinds of methods of outside method are combined, and practical processing condition are provided.Make surrounding layer with the OVD legal system, preparation cost compares low 60% with tiretube process.With the high temperature oxyhydrogen flame solid plug being carried out surface finish between two kinds of methods especially acts on bigger; Coat basic quartz material uniformly in the outside of plug and have the density of two kinds of SiO2 with outer vapour deposition method again, form loose body.The present invention can produce the single-mode fiber prefabricated rods more than 300 kilometers in practice, and draws the single-mode fiber that conforms with quality standard with this rod, has obtained great economic benefit.
Four, description of drawings
Fig. 1 represents to use the MCVD method, and promptly Gai Liang chemical vapor deposition method prepares plug
Fig. 2 represents plug is carried out the thermal treatment of flame polish
Fig. 3 represents to use the OVD method, promptly outer gas-phase deposition, directly deposition glass dust on plug
Fig. 4 represents through the transparent preform of agglomerating
Fig. 5 represents the cross section of optical fiber
Fig. 6 is a graphic representation, and expression OH ion is at the distribution plan of optical wand cross section, i.e. a hydroxy radical content footpath distribution plan (Φ 62.5)
Fig. 7 is a graphic representation, the distribution plan of the density of SiO2 in the expression external sediment process
The shelf 6 of the chuck 3 on oxygen-hydrogen torch 1, quartz glass tube 2, MCVD lathe both sides, glass work lathe 4, oxygen-hydrogen torch 5, OVD lathe, OVD blowtorch 7, SiO2 dust stream 8, the loose body prefabricated rods 9 of plug.
Five, embodiment
The one, when adopting the MCVD method, at first is clipped in a purity quartz glass pipe for high 2 on the chuck 3 on MCVD lathe both sides and rotation as shown in Figure 1,, heats along parallel the moving of silica tube with certain speed as thermal source with oxygen-hydrogen torch 1.A series of gas chemistry mixture (SiCl4, GeCl4, POCl3 etc.) under the drive of current-carrying oxygen, by bubble systems (Bubbler), and by accurate mass flow controller dominant discharge and some other reactant gases (He, Cl2 and O2 etc.), temperature about 1400-1800 ℃ of oxyhydrogen flame issues biochemical reaction, generates superfine little particle deposition in silica tube inside.During every deposition one deck, the glass granules that flame all will just be deposited on the downstream is melt into the very thin glass of one deck.Deposition is in layer gone down like this, and the deposition covering deposits sandwich layer more earlier.After deposition finished, the high temperature with 2100-2300 ℃, became a solid glass plug with the Glass tubing burning shrinkage by for example 2200 ℃.The type of heating of burning shrinkage has: oxygen-hydrogen torch, graphite furnace, plasma flame etc. are several all can.
The 2nd, detects plug with PK2600.Emphasis is to measure parameters such as refractive index profile pattern, core diameter 2a, inner cladding diameter 2b, plug external diameter 2B, refractive index contrast Δ n and useful length L.It is pointed out that the optical fiber that adopts inside deposition prepared of the present invention has center religion high refractive index n1, the size of the inner cladding n2 that relative refractive index is lower and 3, three specific refractory poweres of parent tube layer refractive index n satisfies n1＞n3＞n2.Refractive index contrast Δ n=(n1 wherein
2-n2
2)/(2*n1
2) be the of paramount importance value of the influence optical fiber parameter that draws.According to the data that record, be calculated as the weight that needs external sediment that reaches final qualified optical fiber.With polarimeter plug is carried out the inspection of bubble, surface quality, will when taking over the baton, remove when finding to have problem such as bubble.
The 3rd. as shown in Figure 2, be clipped on the glass work lathe 4, connect bundle of spheres hand and straight grip at its two ends, then it is carried out the thermal treatment of surface finish detecting good plug.Heat treated thermal source is an oxygen-hydrogen torch 5.
Owing to will on plug, directly deposit and sintering in the future, so the cleanliness factor on the interface is very important.When mandrel surface in processes such as detection, after mandrel surface has small breakage or is stained with impurity, it is even to form space or density unevenness on every side at impurity during external sediment, cause the loose body around impurity to grill thoroughly, what have then is nucleus with impurity, generates a crystallisate and form bubble there around impurity.
Therefore, need handle the impurity on the surface of plug.In the present method, the present invention adopts oxygen-hydrogen torch that plug is handled.Owing to contain various glass compositions in the plug, GeO2 (this is the doping agent of the most widely used raising specific refractory power) is wherein arranged, the polish temperature of core should not surpass 1725 ℃ (this is the decomposition temperature of GeO2).The key of polishing is temperature and arranges in pairs or groups between the treatment time.Temperature is too high, just the residence time oversize, can influence plug quality, increase loss, increase OH
-Be diffused into the chance of sandwich layer.Temperature is too low, does not have surperficial heat treated effect.
The present invention adopts oxyhydrogen flame, and with big flow, the method for high translational speed is polished, and can effectively remove surface impurity, optimizes the quality of Watch glass simultaneously.According to the needs of polish temperature, control flame.
The 4th. as shown in Figure 3, polished plug is clipped in above the shelf 6 of OVD lathe, earlier light oxyhydrogen flame plug is carried out preheating with special OVD blowtorch 7, then SiCl4 is fed in the oxyhydrogen flame of blowtorch, through flame hydrolysis, generate SiO2 dust stream 8 and be deposited on above the mandrel surface,, finally obtain the loose body prefabricated rods 9 of uniform outer diameter through about 6-9 hour deposition.Sedimentary at first one deck or one deck to five are layer with interior density with a SiO2 during external sediment, purpose is will allow avoid density variation excessive and cause sliding phenomenon when sintering between glass and the loose body, and all the other each layers, density with the 2nd SiO2, overflow to help bubble, be deposited on outmost loose volume density uniformity as far as possible.The density of the one SiO2 will be significantly higher than the density of the 2nd SiO2, the density of a general SiO2 is got 0.9-1.1, the density that is significantly higher than the 2nd SiO2 is got 0.4-0.7, density control realizes that by the flow of rate of flame travel and silicon tetrachloride Fig. 7 shows the density distribution situation of the SiO2 in the external sediment process easily.
The 5th. as shown in Figure 4, the loose body prefabricated rods that deposition is good is with the speed rotation of 10rpm and hang in the sintered pipes 12, and sintered pipes has and is used to protect prefabricated rods not contaminated, makes the functions such as sintering of the stable and safety of barred body.Sintered pipes is as for the center of the electric furnace 10 that evenly heats around Si-Mo rod.Furnace temperature is warmed up to earlier about 1100-1200 ℃, allows dry gas, the mixture as the gases such as helium of the chlorine of 0.6lpm and 2lpm slowly dewaters approximately 1-3 hour from the bottom to top by prefabricated rods.Temperature is raised to 1400-1600 ℃ then, increases the flow of chlorine and helium, carry out sintering, allow loose SiO2 particle fusion at high temperature, discharge gas inside, loose like this body has just become transparent glass preform 11.In one embodiment, loose body prefabricated rods is heated to 1400-1600 ℃ and carries out sintering, send speed nearly 12mm/min down, and velocity of rotation is 10rpm.
In some cases, can contain bubble and impurity on the interface of the plug of finished product prefabricated rods and surrounding layer.Some bubble is a visible, and size wherein comprises helium and/or other rare gas elementes about 0.5mm, in some cases, also contain aerobic, and optical fiber can rupture or diameter changes during wire drawing.Some bubble is minimum, is because the chlorine in the parent tube is diffused on the interface under agglomerating high temperature.Situation about also having is exactly the impurity that deposition gets in the deposition process outside, and this type of impurity is generally fewer.Therefore, adopting suitable temperature and the following speed of sending is to reduce the effective means of interface bubble.
The 6th. the transparent prefabricated rods that will sinter places in the annealing furnace heat-treats, and the structure and the sintering oven of annealing furnace are roughly the same.Each part all will be heated to sufficiently high temperature through the high-temperature zone, and will continue for some time, so that allow helium and other possible gases of remaining in the rod have time enough to overflow.The time length that stops will be judged according to the diameter and the degree of depth of bubble in rod of rod.
In an example, earlier the glass dust is deposited on the plug, make the loose body prefabricated rods of the column with first external diameter, have the transparent prefabricated rods of second external diameter through forming behind the dehydration sintering, again rod is drawn into prefabricated rods, and the 3rd external diameter is less than second external diameter with the 3rd external diameter.If in the discovery rod bubble is arranged, can segmentation slice off the back wire drawing.
The 7th. adopt the geometric parameter and the optical parametric of PK2600 and polarimeter measuring optical fiber prefabricated rods.As shown in Figure 5, qualified prefabricated rods has following size and parameter.
Diameter
Core diameter 13 4.5-6.0mm
Inner cladding diameter 14 12.05-16.2mm
Parent tube layer diameter 15 21.15-28.2mm
Surrounding layer diameter 16 63-84mm
Claims (3)
1. method of making preform may further comprise the steps:
A) deposit covering and sandwich layer in the inside of pure silica tube earlier with inner vapour deposition method,
B) silica glass that will deposit sandwich layer molten solid plug that shortens under 2100-2300 ℃ of high temperature;
C) with 2000-2100 ℃ high temperature oxyhydrogen flame the solid plug is carried out surface finish;
D) coat uniform quartz material with outer vapour deposition method in the outside of plug, form loose body prefabricated rods, in the depositing operation that is adopted, sedimentary at first one deck or which floor have a SiO during external sediment
2Density, and all the other each layers have the 2nd SiO
2Density, a SiO
2Density to be significantly higher than the 2nd SiO
2Density;
E) this loose body is carried out heat slowly, sinter transparent large prefabricated optical fiber bar into, the specific refractory power of surrounding layer is near the specific refractory power of pure silica tube.
2, the method for making preform as claimed in claim 1, it is characterized in that earlier the glass dust being deposited on the plug, make the loose body prefabricated rods of the column with first external diameter, has the transparent prefabricated rods of second external diameter through forming behind the dehydration sintering, again rod is drawn into prefabricated rods, and the 3rd external diameter is less than second external diameter with the 3rd external diameter.
3, make the method for preform according to claim 1, sedimentary at first one deck or one deck to five layer have a SiO with interior when it is characterized in that external sediment
2Density, all the other each layers have the 2nd SiO
2Density, a SiO
2Density to be significantly higher than the 2nd SiO
2Density, a SiO wherein
2Density get 0.9-1.1, the 2nd SiO
2Density get 0.4-0.7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02138036 CN1197798C (en) | 2002-07-29 | 2002-07-29 | Method for producing fibre-optical precast stick |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02138036 CN1197798C (en) | 2002-07-29 | 2002-07-29 | Method for producing fibre-optical precast stick |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1472150A CN1472150A (en) | 2004-02-04 |
| CN1197798C true CN1197798C (en) | 2005-04-20 |
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| CN 02138036 Expired - Fee Related CN1197798C (en) | 2002-07-29 | 2002-07-29 | Method for producing fibre-optical precast stick |
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Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4789689B2 (en) * | 2006-04-18 | 2011-10-12 | 信越化学工業株式会社 | Low loss optical fiber preform manufacturing method |
| ATE532752T1 (en) * | 2007-01-02 | 2011-11-15 | Draka Comteq Bv | EXTENDED BAKING PROCESS FOR QUARTZ GLASS DEPOSITION TUBE |
| JP5213116B2 (en) * | 2008-09-05 | 2013-06-19 | 信越化学工業株式会社 | Method for manufacturing preform for optical fiber |
| CN101538113B (en) * | 2009-04-27 | 2011-08-03 | 中天科技精密材料有限公司 | Method for preparing a microgap sleeve optical fiber prefabrication bar and method for drawing and preparing an optical fiber by microgap sleeve optical fiber prefabrication bar |
| CN102621629B (en) * | 2012-04-11 | 2014-02-12 | 江苏法尔胜光子有限公司 | 980-nanometer optical fiber for coupler and production method thereof |
| JP6158731B2 (en) * | 2013-04-08 | 2017-07-05 | 信越化学工業株式会社 | Manufacturing method of glass preform for optical fiber and glass preform for optical fiber |
| CN105859119B (en) * | 2016-03-31 | 2018-06-26 | 杭州富通通信技术股份有限公司 | The processing method of optical fiber |
| CN107357004B (en) * | 2017-07-04 | 2020-04-21 | 长飞光纤光缆股份有限公司 | Low-attenuation single-mode optical fiber and preparation method thereof |
| CN110357411B (en) * | 2019-07-29 | 2021-09-21 | 富通集团有限公司 | Preform manufacturing process |
| CN113480162B (en) * | 2019-07-29 | 2022-11-04 | 富通集团有限公司 | Prefabricated excellent processing equipment |
| CN112794639B (en) * | 2021-03-30 | 2021-08-03 | 藤仓烽火光电材料科技有限公司 | Method and equipment for regulating and controlling rod external gas phase deposition |
| CN115010360B (en) * | 2022-07-14 | 2024-04-09 | 中天科技精密材料有限公司 | Preparation method of optical fiber preform, optical fiber preform and optical fiber |
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- 2002-07-29 CN CN 02138036 patent/CN1197798C/en not_active Expired - Fee Related
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