CN1111514C - A kind of method of making large prefabricated optical fiber bar - Google Patents
A kind of method of making large prefabricated optical fiber bar Download PDFInfo
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- CN1111514C CN1111514C CN00128165A CN00128165A CN1111514C CN 1111514 C CN1111514 C CN 1111514C CN 00128165 A CN00128165 A CN 00128165A CN 00128165 A CN00128165 A CN 00128165A CN 1111514 C CN1111514 C CN 1111514C
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- optical fiber
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Abstract
The present invention relates to a kind of method of making large prefabricated optical fiber bar, chemical vapor deposition method deposits core and clad material in comprising of this method: a, the usefulness pipe in quartz glass tube, b, the silica glass that will deposit core and clad material are put the molten plug that shortens under the high temperature, c, adopt silicon tetrachloride to deposit outsourcing layer on plug with outside chemical vapor deposition method, d, the plug that will deposit enough outsourcing layers sinter the transparent glass rod into.Processing method of the present invention is flexible, easy, and raw material sources are abundant, both can obtain the higher core of precision/covering optical waveguide structure, can realize high throughput rate again, can be suitable for making high-quality large prefabricated optical fiber bar.
Description
The present invention relates to a kind ofly make the processing method of large prefabricated optical fiber bar in conjunction with the chemical vapor deposition in outside, belong to optical fiber and make the field with chemical vapor deposition method in the pipe.
The optical fiber that is used for communications is to be made through wire drawing by preform, and the making of preform is an important step in the optical fiber production.Had the processing method of several production preforms in the prior art, as plasma chemical vapor deposition method (PCVD), correction chemical vapor deposition method (MCVD), VAD (VAD), OVD (OVD) etc.Wherein VAD method and OVD are owned by France in outside chemical vapor deposition method, can make large prefabricated optical fiber bar with two-forty, the common every meter excellent length of this large prefabricated optical fiber bar can be pulled out the optical fiber more than 100 kilometers, but outside chemical vapor deposition method is lower to the control accuracy of prefabricated rods waveguiding structure.PCVD method and MCVD owned by France in the pipe in chemical vapor deposition method, though it can produce the higher preform of waveguiding structure precision, but owing to be subjected to the restriction of substrate tube diameter/wall thickness, exist problems such as production cost height, sedimentation rate are lower when using separately, be difficult to make large prefabricated optical fiber bar.Usually the preform of 1 meter length making can only produce more than 20 kilometer optical fiber.And make large prefabricated optical fiber bar with two-forty is the key that improves optical fiber production speed comprehensively, reduces cost, strengthens the optical fiber production market competitiveness of enterprises.
Chemical vapor deposition method has had open source literature to introduce tiretube process with the higher large prefabricated optical fiber bar of two-forty manufacturing accuracy in the pipe in order to utilize.This tiretube process is to produce plug with chemical vapor deposition in the pipe earlier, this plug is inserted one ruler cun suitable quartz glass tube (sleeve pipe) again, uses heat, and plug and sleeve pipe are fused into one, and becomes large prefabricated optical fiber bar.This tiretube process has been used for conventional production, is and one of the most approaching technology of the present invention.But this tiretube process still has following weak point:
1. the core of prefabricated rods/optical fiber of being produced-covering concentricity is bigger;
2. used sleeve pipe, the geometric accuracy height that especially large-sized sleeve pipe requires is difficult to make, and costs an arm and a leg;
3. the telescopic size must be according to the apolegamy of the size of plug, because the telescopic size is that certain specification is arranged, often is difficult to the sleeve pipe that finds size suitable for the plug of the different size of producing.
In order to improve the deficiency of above-mentioned tiretube process, a kind of APVD technology is disclosed in " optical communication forum, the collection of thesis " published in December, 1999, this technology is to produce plug with chemical vapor deposition in the pipe earlier, again with the high frequency plasma blowtorch the molten plug outside of being formed on of mineral crystal powder, become large prefabricated optical fiber bar.This APVD technology has been used for conventional production.The APVD technology is and two of the most approaching technology of the present invention.This technology has remedied the weak point of tiretube process.But this technology still has following problem:
1, the purity of mineral crystal powder is limited, and wherein some impurity is influential to the tensile strength of optical fiber;
2, the mineral crystal powder is from high-quality mineral crystal mineral products, and the present China of this high-quality mineral crystal mineral products does not also have, and from the whole world, natural resource are always limited.
The objective of the invention is to overcome the deficiency that above-mentioned prior art exists and a kind of processing method that can make the high quality large prefabricated optical fiber bar with high productivity is provided.
Purpose of the present invention is realized by following technical scheme:
Chemical vapor deposition method deposits core and clad material in a, the usefulness pipe in quartz glass tube,
B, the silica glass that will deposit core and clad material place the molten plug that shortens under the 1800-2200 ℃ of high temperature,
C, adopt the silicon tetrachloride raw material on plug, to deposit outsourcing layer with outside chemical vapor deposition method,
D, the plug that will deposit enough outsourcing layers sinter the transparent glass rod into, promptly make required large prefabricated optical fiber bar.
Press such scheme, chemical vapor deposition method is for revising chemical vapor deposition method or plasma chemical vapor deposition method in the described pipe; Described outside chemical vapor deposition method is the OVD method.
Technical solution of the present invention further specify into:
The first, at first deposit core and clad material with chemical vapor deposition method in the pipe on the internal surface of quartz glass tube, quartz glass tube is installed on 2 synchronous rotary chucks of glass work lathe.As thermal source, this blowtorch heats quartz glass tube along the quartz glass tube longitudinal translation with controlled speed with hydrogen-oxygen flame blowtorch.One end of quartz glass tube links to each other with the chemical feedstocks supply system, so that with the chemical feedstocks (SiCl of various necessity
4, GeCl
4, POCl
3, O
2, Cl
2, He, CF
2Cl
2Or the like) mix and import quartz glass tube with the amount of control.The flow direction of chemical feedstocks mixture is consistent with the forward translation direction of blowtorch.Enter the hot-zone (1300-1800 ℃) of blowtorch heating when the chemical feedstocks mixture, chemical reaction promptly takes place, the little material of glass that generates sub-micron is deposited on the internal surface of quartz glass tube in downstream, hot-zone, is melt into the glassy membrane of one deck high optical quality subsequently.Blowtorch moves to the outlet side of quartz glass tube and just returns inlet end at a high speed, begins the 2nd layer of deposition, can carry out a lot of layer deposition successively.The chemical feedstocks the ingredients of a mixture that changes corresponding settled layer by production engineering specifications just can obtain necessary core/covering optical waveguide structure.Importantly: the deposition of core material wants enough big, makes the molten ratio C1 of core diameter (2A) and diameter of mandrel (2B) behind the plug that shortens into much larger than the core diameter (2a) of final optical fiber and the ratio C2 of optical fiber jacket diameter (2b).Be C1=2A/2B; C2=2a/2b; C1＞C2; C1 and C2 difference are big more, and prefabricated rods diameter in the future is just big more.For the single-mode fiber prefabricated rods, should make C1/C2 〉=2 at least.Also available microwave plasma substitutes hydrogen-oxygen flame blowtorch and manages interior deposition, and technological process and said process are basic identical.
The hyaline-quartz pipe that the second, will be deposit core and clad material in pipe places and moltenly under 1800-2200 ℃ the high temperature shortens a stuffed quartz glass stick into, is plug, and this plug has the necessary core/cladding structure of leaded light.The type of heating that adopts during molten contracting has multiple, as hydrogen-oxygen flame blowtorch, graphite furnace, high frequency plasma torch or the like.
Three, with opticinstrument the quality of plug is tested earlier.Emphasis is to measure C1 and diameter of mandrel 2B.Calculate the desired prefabricated rods diameter of the C2 value D that desires to reach final optical fiber according to the C1 value of measuring.Calculate the amount (thickness) of essential surrounding layer deposition material according to 2B and D.Use outside chemical vapor deposition method (OVD) on plug, to deposit outsourcing layer then, plug can be installed on the external sediment lathe, as the target rod; The silicon tetrachloride chemical raw material vapour is fed blowtorch with fuel gas with different pipelines, and the fuel of blowtorch is hydrogen or Sweet natural gas or methane and combustion-supporting oxygen, also can be high frequency plasma.The flame of blowtorch sprays to the frame target rod on the depositing lathe outside, i.e. plug, this plug along the longitudinal axis while rotating with the flame generation relative translation of blowtorch.Chemical reaction takes place in unstripped gas in torch flame, generate glass granules.These particulates are deposited on the target rod from level to level, form porous matter base rod.After having deposited enough glass granules materials, be that porous matter base rod moves into operation down together with sedimentary glass granules material with plug.
Four, during the porous matter base rod that will deposit enough glass granules materials was packed dehydration-sintering oven into, the temperature of this stove and atmosphere were controlled.At first, in stove, feed exsiccant oxygen and chlorine (or sulfur oxychloride or tetracol phenixin) at 800-1200 degree centigrade, progressively drive away contained organism, moisture and the various metallic impurity of porous matter base rod, then, use the zone sintering mode, at 1400-1600 degree centigrade, feeding exsiccant oxygen and helium sinter porous matter base rod into bubble-free transparent glass rod, i.e. large prefabricated optical fiber bar in stove.This large prefabricated optical fiber bar promptly can be used for drawing optical fiber in the wire-drawing process.
Characteristics of the present invention and positively effect are:
1, because OVD surrounding layer deposition is center with plug is that the axle center symmetry is sedimentary, so the concentricity of prefabricated rods/optical fiber is littler than tiretube process;
2, owing to directly make surrounding layer on plug, saved series of processes such as the necessary grinding of manufacturing sleeve pipe, polishing, trombone slide, measurement, manufacturing cost is lower than tiretube process;
3, because the sedimentary glass granules quantity of material of OVD surrounding layer is accurately controlled in technological process, how much just deposition how much, can be suitable for any plug, increased the handiness of technology.
4, because the used raw material of deposition surrounding layer is not the mineral crystal powder, but silicon tetrachloride, and the silicon tetrachloride material is the byproduct of semi-conductor industry, and domestic source is abundant, and adopts silicon tetrachloride, and complete processing is also comparatively easy;
5, the surrounding layer deposition material that is produced by silicon tetrachloride and oxygen reaction is a synthetic quartz glass, and the chemistry that has passed through again in sintering oven is removed impurity, and therefore, based on very high purity can be improved the tensile strength characteristic of optical fiber;
6, adopt the mode that chemical vapor deposition method combines with outside chemical vapor deposition method in the pipe, both can obtain the higher core of precision/covering optical waveguide structure, can reach high throughput rate again, can be suitable for making high-quality large prefabricated optical fiber bar, comprise multimode optical fibers and single-mode fiber prefabricated rods, in particular for making the single-mode fiber prefabricated rods of long Distance Transmission.
Below describe embodiments of the invention in detail.
Embodiment 1:
Make 62.5/125 μ m gradient multimode optical fiber preform, its C2=62.5/125=0.5.
Make plug with the quartz glass tube of 36mm * 2mm * 1500mm (external diameter * wall thickness * length) earlier, reaction tubes is heated to 1000-1300 ℃ with electric furnace, and keep certain constant temperature, feed the mixed airflow of a certain proportion of silicon tetrachloride vapor, germanium tetrachloride steam and high purity oxygen gas from an end of pipe in pipe, the other end of pipe is kept the interior negative pressure 5-200 torr of pipe with vacuum pump.Microwave with power 500-6000W makes the mixed airflow in the pipe form low pressure plasma, initiating chamical reaction, and at silica glass pipe internal surface formation silica glass depositing of thin film layer.Through after thousands of layers the deposition, use the molten excellent equipment that shortens into, with hydrogen-oxygen flame blowtorch, with very high temperature (2000-2200 ℃) inside deposition the quartz glass tube of core material melt and shorten a stuffed quartz glass stick into, be plug.Measure diameter of mandrel 2B=20mm, core diameter (2A)=14mm, the ratio C1=0.7 of core diameter (2A) and diameter of mandrel (2B), useful length L=1200mm obtains the prefabricated rods diameter D=28mm of requirement.In order to reach desired D, calculate the weight=664g of necessary sedimentary synthetic silica glass particulate in external sediment.The sedimentation rate data of gained rule of thumb, calculating need be carried out the time of external sediment.Parameters input program control computer, again this plug is installed on the external sediment lathe, have 2 hydrogen-oxygen flame blowtorch side by side on this external sediment lathe, silicon tetrachloride vapor feeds blowtorch with fuel gas with different pipelines, spout place at blowtorch is mixed, light blowtorch, just can deposit by preset program.The heat that the hydrogen-oxygen flame produces makes silicon tetrachloride vapor and oxygen generation chemical reaction, generates the synthetic silica glass granules of white, is deposited on the outside surface of plug, forms porous matter base rod.After deposition is finished, vertically insert in the special-purpose dehydration-sintering oven forming porous matter base rod, interior aerating oxygen 1000sccm of stove and chlorine 100sccm make furnace temperature rise to 1100 ℃ with the heat-up rate of 5 ℃/min, and constant temperature 1 hour with this understanding, drive away moisture and other various impurity; Then, to dewater-sintering oven top local heating to 1600 ℃, stop chlorine and oxygen, feed helium 1000sccm, upwards promote simultaneously the high-temperature zone of porous matter base rod to 1600 ℃ with certain speed, sintering process takes place during through 1600 ℃ of localized hyperthermia districts in porous matter base rod, loose porous matter base rod changes transparent preform into, and this prefabricated rods can be used for drawing more than 60 kilometer of multimode optical fibers.
Embodiment 2:
Make 8.5/125 μ mG.652 single-mode fiber prefabricated rods, i.e. C2=8.5/125=0.068.
Make plug with the quartz glass tube of 36mm * 2mm * 1500mm (external diameter * wall thickness * length) earlier, feed the mixed airflow of a certain proportion of silicon tetrachloride vapor, phosphorus oxychloride steam, germanium tetrachloride steam and high purity oxygen gas from an end of pipe in pipe, the other end usefulness rotary seal joint of pipe links to each other with the reaction end gas treatment system.Keep pressure-fired 10-20mm water column in the pipe.With semi-circular hydrogen-oxygen flame blowtorch heating quartz glass tube, temperature 1300-1500 ℃, initiating chamical reaction, and at silica glass pipe internal surface formation silica glass depositing of thin film layer.Through after the deposition of tens layers, use the molten excellent equipment that shortens into, with graphite furnace with very high temperature (2000-2200 ℃) inside deposition the quartz glass tube of core material melt and shorten a stuffed quartz glass stick into, be plug.Measure diameter of mandrel 2B=22mm, core diameter (2A)=6mm, the ratio C1=0.27 of core diameter (2A) and diameter of mandrel (2B), useful length L=1200mm obtains the prefabricated rods diameter D=6/0.068=88mm of requirement.In order to reach desired D, calculate the weight of necessary sedimentary synthetic silica glass particulate in external sediment.Rule of thumb the sedimentation rate data of gained calculate the time that need carry out external sediment.Parameters input program control computer, again this plug is installed on the external sediment lathe, have 2 hydrogen-oxygen flame blowtorch side by side on this external sediment lathe, silicon tetrachloride vapor feeds blowtorch with fuel gas with different pipelines, spout place at blowtorch is mixed, light blowtorch, just can deposit by preset program.The heat that the hydrogen-oxygen flame produces makes silicon tetrachloride vapor and oxygen generation chemical reaction, generates the synthetic silica glass particulate of white, is deposited on the outside surface of plug, forms porous matter base rod.After deposition is finished, vertically insert in the special-purpose dehydration-sintering oven forming porous matter base rod, interior aerating oxygen 1000sccm of stove and chlorine 100sccm make furnace temperature rise to 1100 ℃ with the heat-up rate of 5 ℃/min, and constant temperature 1 hour with this understanding, drive away moisture and other various impurity; Then, to dewater-sintering oven top local heating to 1600 ℃, stop chlorine and oxygen, feed helium 1000sccm, upwards promote simultaneously the high-temperature zone of porous matter base rod to 1600 ℃ with certain speed, sintering process takes place during through 1600 ℃ of localized hyperthermia districts in porous matter base rod, loose porous matter base rod changes transparent preform into, and this prefabricated rods can be used for drawing more than 590 kilometer of multimode optical fibers.
Claims (6)
1, a kind of method of making large prefabricated optical fiber bar, it is characterized in that: chemical vapor deposition method deposits core and clad material in a, the usefulness pipe in quartz glass tube, b, the silica glass that will deposit core and clad material are put the molten plug that shortens under the 1800-2200 ℃ of high temperature, c, adopt the silicon tetrachloride raw material on plug, to deposit outsourcing layer with outside chemical vapor deposition method, d, the plug that will deposit enough outsourcing layers sinter the transparent glass rod into, promptly make required large prefabricated optical fiber bar.
2,, it is characterized in that chemical vapor deposition method is for revising chemical vapor deposition method or plasma chemical vapor deposition method in the described pipe by the method for the described making large prefabricated optical fiber bar of claim 1.
3, by the method for claim 1 or 2 described making large prefabricated optical fiber bars, it is characterized in that described outside chemical vapor deposition method is the OVD method.
4,, it is characterized in that when fusing into plug, adopting hydrogen-oxygen flame blowtorch or graphite furnace or high frequency plasma torch as thermal source by the method for claim 1 or 2 described making large prefabricated optical fiber bars.
5, press the method for claim 1 or 2 described making large prefabricated optical fiber bars, be it is characterized in that vertically inserting in dehydration-sintering oven form porous matter base rod, aerating oxygen 1000sccm and chlorine 100sccm in the stove, heat-up rate with 5 ℃/min makes furnace temperature rise to 1100 ℃, and constant temperature 1 hour with this understanding, drive away moisture and other various impurity; Then, to dewater-sintering oven top local heating to 1600 ℃, stop chlorine and oxygen, feed helium 1000sccm, upwards promote simultaneously the high-temperature zone of porous matter base rod to 1600 ℃ with certain speed, sintering process takes place during through 1600 ℃ of localized hyperthermia districts in porous matter base rod, and loose porous matter base rod changes transparent preform into.
6, press the method for claim 1 or 2 described making large prefabricated optical fiber bars, the deposition that it is characterized in that core material wants enough big, makes the molten ratio C1 of core diameter (2A) and diameter of mandrel (2B) behind the plug that shortens into much larger than the core diameter (2a) of final optical fiber and the ratio C2 of optical fiber jacket diameter (2b).Be C1=2A/2B; C2=2a/2b:C1＞C2; C1 and C2 difference are big more, and prefabricated rods diameter in the future is just big more, for the single-mode fiber prefabricated rods, should make C1/C2 〉=2 at least.
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|---|---|---|---|
| CN00128165A CN1111514C (en) | 2000-12-28 | 2000-12-28 | A kind of method of making large prefabricated optical fiber bar |
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|---|---|---|---|
| CN00128165A CN1111514C (en) | 2000-12-28 | 2000-12-28 | A kind of method of making large prefabricated optical fiber bar |
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| CN1297856A CN1297856A (en) | 2001-06-06 |
| CN1111514C true CN1111514C (en) | 2003-06-18 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1300609C (en) * | 2003-10-28 | 2007-02-14 | 长飞光纤光缆有限公司 | High performance chromatic dispersion compensation optical fiber and its producing method |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100518057B1 (en) * | 2002-11-07 | 2005-09-28 | 엘에스전선 주식회사 | Method of Manufacturing an Optical Fiber Preform by MCVD |
| CN1323043C (en) * | 2003-04-23 | 2007-06-27 | 中国建筑材料科学研究院 | Process for synthesizing guartz glass by vertical silicon tetrachloride vapor deposition |
| JP4385681B2 (en) * | 2003-08-11 | 2009-12-16 | 住友電気工業株式会社 | Optical fiber preform manufacturing method and optical fiber manufacturing method |
| CN1847179B (en) * | 2005-04-13 | 2010-09-08 | 富通集团有限公司 | Production process of fiber preform rod |
| CN101182113B (en) * | 2007-11-20 | 2011-02-09 | 长飞光纤光缆有限公司 | PCVD method for making large-diameter fibre-optical mandrel |
| 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 |
| CN110078366B (en) * | 2019-03-11 | 2020-10-27 | 江苏永鼎股份有限公司 | High-core-coated-concentricity optical fiber and preparation method thereof |
| CN111029054B (en) * | 2019-12-09 | 2020-12-22 | 华南理工大学 | Prefabricated core rod of optical fiber composite insulator, mold and manufacturing method of prefabricated core rod |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN87105714A (en) * | 1986-07-03 | 1988-02-03 | 住友电气工业株式会社 | Method for manufacturing fiber preform for single mode optical fiber |
-
2000
- 2000-12-28 CN CN00128165A patent/CN1111514C/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN87105714A (en) * | 1986-07-03 | 1988-02-03 | 住友电气工业株式会社 | Method for manufacturing fiber preform for single mode optical fiber |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1300609C (en) * | 2003-10-28 | 2007-02-14 | 长飞光纤光缆有限公司 | High performance chromatic dispersion compensation optical fiber and its producing method |
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| CN1297856A (en) | 2001-06-06 |
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