CN102923942B - The preparation method of large-scale optical fiber prefabricating stick - Google Patents
The preparation method of large-scale optical fiber prefabricating stick Download PDFInfo
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- CN102923942B CN102923942B CN201210435105.0A CN201210435105A CN102923942B CN 102923942 B CN102923942 B CN 102923942B CN 201210435105 A CN201210435105 A CN 201210435105A CN 102923942 B CN102923942 B CN 102923942B
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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]
- C03B37/01446—Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/50—Glass production, e.g. reusing waste heat during processing or shaping
- Y02P40/57—Improving the yield, e-g- reduction of reject rates
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Abstract
The present invention relates to a kind of preparation method of large-scale optical fiber prefabricating stick, comprise the steps: adopt axial vapor deposition method and prepare transparent solid quartz pushrod through subsequent disposal, described transparent solid quartz pushrod comprises sandwich layer and part of clad; Transparent solid quartz pushrod is set in high-purity thick-wall quartz tube and shortens the uniform elementary preform of a root architecture into by high temperature melting; The rod using this elementary preform as target, with Outside Vapor deposition method SiO
2surrounding layer, after having deposited, is sintered into transparent preform.Present invention obviates many intermediate step that tiretube process prepares optical fiber, effectively can not only improve the production efficiency of preform, reduce costs, and processing performance is stablized, Fiber Optical Parametric is excellent, is convenient to large-scale production.
Description
Technical field
The present invention relates to a kind of preparation method of large-scale optical fiber prefabricating stick, belong to optic fibre manufacturing technology field.
Background technology
Preform preparation is the master operation of optic fibre manufacturing technology.Adopt large-scale optical fiber prefabricating stick wire drawing effectively can improve utilization rate of raw materials, can effectively save the production time simultaneously and enhance productivity, large-scale optical fiber prefabricating stick has become Vehicles Collected from Market main trend.Current large-scale optical fiber prefabricating stick is divided into: large size solid preform and sleeve pipe add plug prefabricated rods form.
The current method accounting for the large-scale preformod of optical fiber with low water peak of main flow is tiretube process, as US005837334A, US007089765B2.Current tiretube process first produces plug, then this plug is inserted the quartz glass tube of size match, plug and sleeve pipe synchronously melted merge prolongation to become photoconductive fiber through heat.Tiretube process has the following disadvantages: the geometric accuracy that large-sized sleeve pipe requires is high, and manufacturing process is complicated, and the material unaccounted-for (MUF) in the sleeve pipe course of processing causes cost to increase.The interface of plug and sleeve pipe adds the complexity of drawing optical fibers technique, the cleaning at interface and drying become stricter, and interface adds the probability of mechanical fiber optic strength weak link generation, add the possibility of unit length fibercuts, interface also has a negative impact to optical fiber water peak (because hydroxyl absorption peak within the scope of 1360nm ~ 1460nm is called water peak in Optical Fiber Transmission), the production cost that the technical process waiting elimination interface added influence to add adds prefabricated rods is washed in plasma erosion, and sleeve pipe is expensive.
OVD method is by the SiO of multiple blowtorch by hydrolysis
2particle deposition rotation and on the plug of relative movement.Sedimentation rate is high, but this deposition method easily forms shape of threads or corrugated surface, and plug two ends are uneven makes whole deposition rod form fusiform, and then the optical fiber geometric parameter causing whole rod to be drawn into and the uneven instability of optical parametric.
VAD method and OVD method have identical flame hydrolysis mechanism.Sedimentation rate is the greatest drawback of VAD slowly, but its advantage is process stabilizing, deposit obtain loosening body composition structure and geometrical dimension even.
In pipe, method PCVD and MCVD is suitable for preparing high-precision complex construction, but both sedimentation rates are lower, less than 3g/min, and in pipe, method cannot prepare separately the prefabricated rods of large gauge, reach 99.9999% to the purity requirement of unstripped gas, high cost makes application be restricted.
APVD sedimentation rate is higher, but its raw material high-purity natural quartz sand is with high costs and homogeneity is wayward makes the not easily widespread use of this technique.
terms more of the present invention are defined as:
Deposition: the technological process that physicochemical change generates silica glass occurs starting material under certain conditions;
Refractive index profile: the relation curve of prefabricated rods/plug/between fiber glass specific refractory power and its radius;
Thick-wall quartz tube: the quartz glass tube of wall thickness relative tubular diameter large percentage, ratio is greater than 10% usually, and wall thickness is greater than 3mm usually;
VAD: axial vapor deposition;
OVD: Outside Vapor deposits.
Summary of the invention
Technical problem to be solved by this invention is the deficiency that exists for above-mentioned prior art and provides a kind of preparation method of large-scale optical fiber prefabricating stick; it effectively can not only improve the production efficiency of preform; reduce costs; and processing performance is stablized; Fiber Optical Parametric is excellent, is convenient to large-scale production.
The technical scheme that the problem that the present invention is the above-mentioned proposition of solution adopts is:
The method comprises the following steps: adopt axial vapor deposition method (VAD) and prepare transparent solid quartz pushrod through subsequent disposal, described transparent solid quartz pushrod comprises sandwich layer and part of clad; Transparent solid quartz pushrod is set in high-purity thick-wall quartz tube and shortens the uniform elementary preform of a root architecture into by high temperature melting; Using this elementary preform as target, rod, deposits SiO by Outside Vapor sedimentation (OVD)
2surrounding layer, after having deposited, is sintered into transparent preform.
By such scheme, the covering/sandwich layer diameter ratio (b/a) of described transparent solid quartz pushrod is 1.8 ~ 3.
By such scheme, the subsequent disposal of described axial vapor deposition method is that loosening body axial vapor deposition method made changes transparent stuffed quartz rod into after dehydration sintering, then Shape correction is carried out, comprise melting, stretching, grinding, polishing, chemolysis, cleaning, make its uniform diameter, any surface finish, transparent solid quartz pushrod surfaceness is less than or equal to 20 μm.
By such scheme, the SiO that described axial vapor deposition legal system is standby
2the part more than 2/3 that loosening body useful length in the axial direction accounts for the axial overall length of loosening body is significant part, and the diameter fluctuation scope of this significant part is less than 4%.
By such scheme, described high-purity thick-wall quartz tube inner bore surface roughness is less than or equal to 20 μm, and hydroxy radical content is less than or equal to 100ppb, and external diameter is 1.5 ~ 1.8 with the ratio of diameter of bore.
By such scheme, described preform diameter D is 120 ~ 200mm.
By such scheme, described optical fiber prefabricating nose is through fused biconical taper process, and make optical fiber prefabricating nose coning or approximate circle taper, conical height H is 0.2 ~ 1.1 with the ratio H/D of preform diameter D, and comparatively ratio of greater inequality value is 0.3 ~ 0.4.
By such scheme, Outside Vapor deposition method SiO
2the diameter fluctuation of the transparent optical fiber preform sintered into after surrounding layer for significant part except tapering is less than 1mm.
Beneficial effect of the present invention is: the advantage 1, combining VAD method and OVD method, wherein VAD sedimentation rate is moderate, be easy to control the hydroxy radical content in prefabricated rods, maximum fiber core layer material weight can be obtained, OVD method sedimentation rate is the highest, and preparation requires that lower surrounding layer part makes prefabricated rods cost reduce.Avoid both shortcomings with thick-wall quartz tube suit fusion process, not only effectively improve the production efficiency of preform, reduce costs, and processing performance is stablized, Fiber Optical Parametric is excellent, is convenient to large-scale production; 2, by the covering of transparent solid quartz pushrod/sandwich layer diameter ratio (b/a) controls 1.8 ~ 3, adopt high-purity thick-walled quartz to overlap the mode of the thickness of pipe simultaneously, although many molten contracting operations of suit together, but more sandwich layer glass weight can be obtained, hydroxyl is avoided to spread the core covering introducing transparent solid quartz pushrod, make final preform can weigh 70 kilograms, obtain the large-scale optical fiber prefabricating stick of better quality; 3, the shaping of tapering, preform front end can save Wire Drawing time and materials cost further.The technical solution used in the present invention avoids many intermediate step that tiretube process prepares optical fiber, preform manufacturing cost is down to minimum.
Accompanying drawing explanation
Fig. 1 is the process flow diagram of preform preparation method of the present invention.
Fig. 2 is the axial sectional structure schematic diagram of preform of the present invention, and 1 represents the sandwich layer part that VAD method deposits, and 2 represent the clad section that VAD methods deposit, and 3 represent the silica glass member that thick-walled tubes are corresponding, and 4 represent that OVD method deposits the silica glass member of preparation.D value represents the diameter of the finished product preform, and H represents the height of prefabricated rods cone.
Fig. 3 is the radial sectional structure schematic diagram of preform of the present invention, a and b in figure represents sandwich layer and clad section diameter respectively, and D value represents the diameter of the finished product preform.
Embodiment
Below in conjunction with drawings and Examples, the present invention is further illustrated.
The present invention is suitable for preparing large-scale preformod of optical fiber with low water peak, composition (the Ge of unstripped gas is set in described VAD method, F, Cl) silica glass of various doping composition can be obtained, in thick-walled tube, mix F, Cl, P etc. can obtain different melt viscosity and specific refractory power, thus the refractive index profile structure (RIP) of preform can be adjusted, this is apparent concerning those skilled in the art.Hereafter in conjunction with several typical large prefabricated optical fiber bar manufacture method, technical solution of the present invention is specifically described.
embodiment one: matched cladding low water peak single mode fiber prefabricated rods.
Transparent solid quartz pushrod is prepared with VAD, comprise sandwich layer and part of clad, loosening body prepared by VAD changes transparent stuffed quartz rod into after dehydration sintering, then Shape correction is carried out, after this transparent solid quartz pushrod shaping, covering/sandwich layer diameter is 2.9 ~ 3 than b/a, significant part length reaches 2/3 of total length, and significant part diameter fluctuation scope is less than 4%, and transparent solid quartz pushrod surfaceness is less than 20 μm.It is a quartz pushrod that the high-purity thick-wall quartz tube this quartz pushrod and external diameter 45mm, internal diameter 28mm, inside surface roughness being less than 20 μm is set with molten shortening into, and obtain the elementary preform of even structure, the hydroxy radical content of this thick-walled tube is less than 100ppb.Using this preform as target, rod, deposits SiO by outside method (OVD)
2surrounding layer, after having deposited, is sintered into the transparent optical fiber preform of diameter 120mm.The rear end of this prefabricated rods connects extension tube as drawing wire machine feeder clamping, front end is suspension end, start for ease of wire drawing, this suspension end is through fused biconical taper and be shaped to approximate circle taper by grinding and polishing, and the height of cone and the ratio H/D of preform diameter are 1.1.Afterwards this preform drawing is become matches criteria covering low water peak single mode fiber, the effective length of string of continuous print is about 1000km, and optical fiber is 0.268dB/km at the reduction coefficient of 1383nm window.
embodiment two: covering single-mode fiber prefabricated rods of sinking.
Prepare transparent solid quartz pushrod with VAD, comprise sandwich layer and part of clad, this covering contains F, and after this transparent solid quartz pushrod shaping, covering/sandwich layer diameter is 2.4 than b/a.The high-purity thick-wall quartz tube this quartz pushrod and external diameter 45mm, internal diameter 28mm, inside surface roughness being less than 20 μm is set with fusion becomes a quartz pushrod, and obtain the elementary preform of even structure, the hydroxy radical content of this thick-walled tube is less than 100ppb.Using this preform as target, rod, deposits SiO by outside method (OVD)
2surrounding layer, after having deposited, is sintered into the transparent optical fiber preform of diameter 150mm.This prefabricated rods one end is suspension end, and start for ease of wire drawing, this suspension end is shaped to approximate circle taper through fused biconical taper and by grinding and polishing, and the height of cone and the ratio of basal diameter are 0.2.This preform drawing become standard to sink covering low water peak single mode fiber afterwards, the effective length of string of continuous print is about 1400km, and optical fiber is 0.274dB/km at the reduction coefficient of 1383nm window.
embodiment three: low water peak bend resistant single moded fibers prefabricated rods.
Prepare transparent solid quartz pushrod with VAD, comprise sandwich layer and part of clad, after this transparent solid quartz pushrod shaping, cored is 1.8 than b/a.It is a quartz pushrod that the high-purity thick-wall quartz tube this quartz pushrod and external diameter 50mm, internal diameter 30mm, inside surface roughness being less than or equal to 20 μm is set with molten shortening into, obtain the elementary preform of even structure, this thick-walled tube contains F and hydroxy radical content is less than 50ppb.Using this preform as target, rod, deposits SiO by outside method (OVD)
2surrounding layer, after having deposited, sintered into the transparent optical fiber preform of diameter 200mm, the diameter fluctuation of its significant part is less than 1mm.This prefabricated rods one end is suspension end, and this suspension end is shaped to approximate circle taper through fused biconical taper and by grinding and polishing, and the height of cone and the ratio of basal diameter are 0.3 ~ 0.4.Apparently, this prefabricated rods also can carry out melting, stretching, grinding, polishing, chemolysis, cleaning Shape correction as required to meet the requirement of fiber drawing furnace cavity internal diameter.Afterwards this preform is carried out wire drawing and make the counter-bending single-mode fiber in low water peak, the effective length of string of continuous print is about 2400km, optical fiber is 0.277dB/km at the reduction coefficient of 1383nm window, and under the condition of 1550nm window 10mm diameter 1 circle, additional macrobending loss is 0.08dB.
Claims (5)
1. a preparation method for large-scale optical fiber prefabricating stick, is characterized in that comprising the steps:
Adopt axial vapor deposition method and prepare transparent solid quartz pushrod through subsequent disposal, described transparent solid quartz pushrod comprises sandwich layer and part of clad; Transparent solid quartz pushrod is set in high-purity thick-wall quartz tube and shortens the uniform elementary preform of a root architecture into by high temperature melting; The rod using this elementary preform as target, with Outside Vapor deposition method SiO
2surrounding layer, after having deposited, is sintered into transparent preform; Covering/sandwich layer the diameter of described transparent solid quartz pushrod is 1.8 ~ 3 than b/a; Described high-purity thick-wall quartz tube inner bore surface roughness is less than or equal to 20 μm, and hydroxy radical content is less than or equal to 100ppb, and external diameter is 1.5 ~ 1.8 with the ratio of diameter of bore; The subsequent disposal of described axial vapor deposition method is that loosening body axial vapor deposition method made changes transparent stuffed quartz rod into after dehydration sintering, then Shape correction is carried out, comprise melting, stretching, grinding, polishing, chemolysis, cleaning, make its uniform diameter, any surface finish, transparent solid quartz pushrod surfaceness is less than or equal to 20 μm; Described preform diameter D is 120 ~ 200mm.
2. the preparation method of large-scale optical fiber prefabricating stick according to claim 1, it is characterized in that the part more than 2/3 that the standby loosening body useful length in the axial direction of described axial vapor deposition legal system accounts for the axial overall length of loosening body is significant part, the diameter fluctuation scope of this significant part is less than 4%.
3. the preparation method of large-scale optical fiber prefabricating stick according to claim 1, it is characterized in that described optical fiber prefabricating nose is through fused biconical taper process, make optical fiber prefabricating nose coning or be similar to taper shape, conical height H is 0.2 ~ 1.1 with the ratio H/D of preform diameter D.
4. the preparation method of large-scale optical fiber prefabricating stick according to claim 3, is characterized in that conical height H is 0.3 ~ 0.4 with the ratio H/D of preform diameter D.
5. the preparation method of large-scale optical fiber prefabricating stick according to claim 3, is characterized in that: Outside Vapor deposition method SiO
2the diameter fluctuation of the transparent optical fiber preform sintered into after surrounding layer for significant part except tapering is less than 1mm.
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| CN109081575A (en) * | 2017-06-14 | 2018-12-25 | 中天科技精密材料有限公司 | Preform and its manufacturing method |
| CN112279504B (en) * | 2020-11-30 | 2023-09-26 | 江苏亨通光导新材料有限公司 | Preparation device and preparation method of optical fiber preform |
| CN113998880B (en) * | 2021-10-08 | 2023-02-24 | 富通集团（嘉善）通信技术有限公司 | Manufacturing method of core rod, preform rod and optical fiber |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1760150A (en) * | 2005-08-17 | 2006-04-19 | 长飞光纤光缆有限公司 | Method for preparing preformod of optical fiber with low water peak in large size |
| CN1765789A (en) * | 2005-09-15 | 2006-05-03 | 长飞光纤光缆有限公司 | Method for making low water peak optical fiber preformrod adopting plasm outward spraying method |
| CN102276145A (en) * | 2011-07-12 | 2011-12-14 | 成都富通光通信技术有限公司 | Manufacturing method of optical fiber perform with uniform optical waveguide axial direction |
| CN102757179A (en) * | 2012-08-02 | 2012-10-31 | 长飞光纤光缆有限公司 | Method for preparing large-size optical fiber preform |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1760150A (en) * | 2005-08-17 | 2006-04-19 | 长飞光纤光缆有限公司 | Method for preparing preformod of optical fiber with low water peak in large size |
| CN1765789A (en) * | 2005-09-15 | 2006-05-03 | 长飞光纤光缆有限公司 | Method for making low water peak optical fiber preformrod adopting plasm outward spraying method |
| CN102276145A (en) * | 2011-07-12 | 2011-12-14 | 成都富通光通信技术有限公司 | Manufacturing method of optical fiber perform with uniform optical waveguide axial direction |
| CN102757179A (en) * | 2012-08-02 | 2012-10-31 | 长飞光纤光缆有限公司 | Method for preparing large-size optical fiber preform |
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