WO1998018733A1 - Appareil et procede pour reduire la fracture des fibres etirees a partir d'ebauches - Google Patents

Appareil et procede pour reduire la fracture des fibres etirees a partir d'ebauches Download PDF

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Publication number
WO1998018733A1
WO1998018733A1 PCT/US1997/018041 US9718041W WO9818733A1 WO 1998018733 A1 WO1998018733 A1 WO 1998018733A1 US 9718041 W US9718041 W US 9718041W WO 9818733 A1 WO9818733 A1 WO 9818733A1
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WO
WIPO (PCT)
Prior art keywords
blank
environment
gas
contaminant
fiber
Prior art date
Application number
PCT/US1997/018041
Other languages
English (en)
Inventor
James E. Dickinson, Jr.
Julian L. Dunn
G. Scott Glaesemann
Bruce W. Reding
James A. Snipes
Donald J. Wissuchek, Jr.
Original Assignee
Corning Incorporated
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Corning Incorporated filed Critical Corning Incorporated
Priority to CA002267970A priority Critical patent/CA2267970A1/fr
Priority to EP97910815A priority patent/EP0963356A4/fr
Priority to JP52049298A priority patent/JP2001507663A/ja
Priority to AU48095/97A priority patent/AU734480B2/en
Publication of WO1998018733A1 publication Critical patent/WO1998018733A1/fr

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Classifications

    • 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
    • C03B37/01202—Means for storing or carrying optical fibre preforms, e.g. containers
    • 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]
    • C03B37/01446—Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering
    • C03B37/0146—Furnaces therefor, e.g. muffle tubes, furnace linings
    • 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
    • C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
    • C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
    • C03B37/027—Fibres composed of different sorts of glass, e.g. glass optical fibres
    • 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
    • C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
    • C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
    • C03B37/029—Furnaces therefor
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2205/00—Fibre drawing or extruding details
    • C03B2205/12—Drawing solid optical fibre directly from a hollow preform
    • C03B2205/16—Drawing solid optical fibre directly from a hollow preform the drawn fibre consisting of circularly symmetric core and clad

Definitions

  • the present invention relates to an apparatus and method for reducing breakage of a fiber dr-wn from a blank and, more particularly, to a holding oven and method that inhibit passive oxidation of a contaminant of a silica- containing blank and/or that minimize surface contamination of the blank.
  • Optical waveguide fibers are a transmission medium used in optical communication systems
  • Optical fibers are typically made by well known methods
  • Strength is an important characteristic of optical fibers. Particulate contaminants on the fiber surface often weaken the fiber and cause flaw initiation and fiber failure under tensile loading. Some optical fibers break under low stress due to such contaminants.
  • breaking fibers contain silicon carbide (SiC) and silicon nitride (Si. 3 N ), which are non-oxide, refractory contaminants. These contaminants are in the size range typical of airborne particles (less than 5 urn) and attach to the surface of the blank before or durir.g the drawing process, thus producing a draw trough on the surface of the fiber.
  • the passivation layer is a solid reaction product of passive oxidation.
  • the provisional application also discloses that the contaminants can be removed by active oxidation.
  • the active oxidation mechanism produces a gaseous reaction product and causes corrosion of the silicon carbide and silicon nitride contaminants.
  • the active oxidation mechanisms for silicon carbide and silicon nitride are represented by the following formulas:
  • the draw process described in the provisional application promotes active oxidation of the contaminants by providing a low-oxygen environment during drawing.
  • the environment of the manufacturing plant may contain particulate contaminants, such as airborne particles of zirconium (Zr) compounds such as zirconia (Zr0 2 ) and calcium (Ca) compounds, that may become attached to the surface of the blank while it is being transferred to the holding oven and/or while it is being held in the holding oven.
  • Zr zirconium
  • Ca calcium
  • S8KTmJTESBEET(KllE2 ⁇ ) typically about 5 to 10 ⁇ m and the contaminants of calcium
  • An object of the present invention is to improve the efficiency of the active oxidation drawing process.
  • SWSTITITEIIET(HIE2 ⁇ ) contaminants in the active oxidation drawing process is designed to improve the efficiency of the active oxidation drawing process by inhibiting passive oxidation of the contaminants and the corresponding formation of passivation layers, before commencement of the active oxidation drawing process.
  • the invention provides an improved method of storing a blank having a refractory contaminant before use in a drawing device in which a fiber is to be drawn from the blank, comprising the steps of disposing the blank in a holding device, and providing an environment in the holding device that inhibits passive oxidation of the refractory contaminant.
  • the invention provides an improved apparatus for storing a blank having a refractory contaminant before use in a drawing device in which a fiber is to be drawn from the blank, comprising a compartment for storing the blank, and a supply device that supplies gas to the compartment to provide an environment in the compartment that inhibits passive oxidation of the refractory contaminant.
  • the invention provides an improved method of storing a blank before use in a drawing device in which a fiber is to be drawn from the blank, comprising the steps of disposing the blank in a holding device, and flowing a gas against a surface of the blank
  • SWSTITIITESBeT(RUIf26) blank in the holding device at a rate sufficient to prevent an environmental contaminant from becoming attached to the surface of the blank.
  • FIG. 1 is a sectional view of a first embodiment of a holding oven according to the present invention.
  • FIG. 2 is a sectional view of a draw furnace.
  • FIG. 3 is a graphic illustration of the transition between the passive and active oxidation mechanisms for silicon carbide.
  • FIG. 4 is a graphic illustration of the growth of a passivation layer on silicon carbide.
  • FIG. 5 is a graphic illustration of the growth of a passivation layer on silicon nitride.
  • FIG. 6 is a sectional view of a second embodiment of a holding oven according to the present invention.
  • FIG. 7 is a top view of a top ring in the holding oven shown in FIG. 6.
  • a passivation layer formed on a silicon carbide or silicon nitride contaminant before a blank enters the draw furnace may inhibit corrosion of the contaminant by active oxidation in the active oxidation drawing process.
  • the passivation layer hinders the reaction by creating a diffusive barrier for oxidation reactants and products.
  • the reaction rate for the corrosion of silicon carbide and silicon nitride is governed by the rate of diffusion of ca r bon monoxide or nitrogen through the passivation layer.
  • SUBSTITUTE SHEET (RUlf 28) contaminant with its passivation layer. If the passivation layer is sufficiently thick, the active oxidation drawing process may not fully remove the contaminant or may remove it so slowly thjc the process is not practical.
  • FIG. 3 shows the boundary between the passive and active oxidation mechanisms depending on the oxygen concentration and temperature.
  • line 70 indicates the experimentally-determined boundary between the passive and active oxidation mechanisms for silicon carbide within specified ranges of partial pressure of oxygen (P 02 ) and temperature.
  • FIG. 3 also shows the results of an experiment that illustrate the active/passive transition. Samples of silicon carbide (greater than 99.9% pure processed mirror finish, Morton Advanced Materials,
  • SUBSTITUTE SHEET 0WLE 28 characteristic of passive oxidation (i.e., film growth).
  • the present invention inhibits the formation of a passivation layer by providing an environment in the holding oven that inhibits passive oxidation.
  • passive oxidation is inhibited by providing an environment that is substantially devoid of oxygen.
  • Such an environment can be provided, for example, by replacing ambient air with argon (Ar) or nitrogen (N 2 ) .
  • the dearth of oxygen causes the passive oxidation mechanism to become essentially inactive .
  • SUBSTITUTE SHEET (RULE 28) The following experiment illustrates this advantage of the present invention.
  • the conditions in a conventional holding oven were simulated by providing an environment, in an electrically heated oven, of ambient air at a constant temperature of 950°C.
  • Samples (each approximately 3 mm x 5 mm) of silicon carbide and silicon nitride were placed in the environment and were removed after hold times of 6 hours, 24 hours, 2 days, 3 days, and 5 days.
  • the silicon carbide samples had ⁇ )lor changes on their mirror surfaces due to thin film growth. After 6 hours, the film began to nucleate at grain boundaries on the silicon carbide surface. At 24 hours, the grain boundaries and several complete grains were covered. At 48 hours, approximately 90?> of the grains were completely oxidized.
  • the remaining grains remained unoxidized due to crystal orientation effects on oxide growth rate.
  • Film growth on the silicon nitride samples was not optically visible due to the matte finish of the samples, but was detected by other means.
  • the thicknesses of the films on the surface of the silicon carbide and silicon nitride samples were measured by depth profiling using electron spectroscopy for chemical analysis (ESCA) . This technique confirmed that the thin films were silica passivation layers.
  • the passivation layers were sputtered using an argon ion beam, and the sputtering continued until the carbon (for silicon
  • FIGS. 4 and 5 show the growth rates for the passivation layers formed on the silicon carbide and silicon nitride samples, respectively.
  • the parabolic growth rates of the passivation layers are typical of rates that are limited by diffusion of the reacting species across a thickening reaction layer.
  • the growth rate equations are:
  • r 0.166 /(t) (silicon nitride) where r is the thickness of the passivation layer in microns, and t is the hold time (at 950°C) in hours.
  • the conditions in holding ovens according to the present invention were simulated by providing environments substantially devoid of oxygen. Argon and nitrogen were each used as purge gases to provide the low-oxygen environments. Silica, silicon carbide, and silicon nitride samples were placed in flowing gas at 950°C for periods of 3 days and 6 days. Oxygen levels were monitored continuously during the experiment, with P 02 being less than 1 part per million (ppm) for the argon environment and approximately 80 ppm
  • holding oven 10 is a conventional holding oven that has been modified to provide an environment that inhibits passive oxidation of contaminants.
  • holding oven 10 includes a compartment for storing a blank, and a supply device that supplies gas to the con.:artment to provide an environment in the compartment that inhibits passive oxidation of a refractory contaminant of the blank .
  • the compartment 12 for storing blank 20 includes a muffle 14 that is centered by centering ring 16 and top seal 18.
  • the top of compartment 12 is covered by a top seal 18 and a cover 22.
  • a handle 24 extends through cover 22 to hold blank 20.
  • Heaters and insulation 26 maintain compartment 12 at an appropriate temperature, preferably about 950°C.
  • the supply device includes a pipe
  • Pipe 28 is connected to a gas reservoir 29 and supplies the gas from reservoir 29 to compartment 12, thereby creating an environment that inhibits passive oxidation of the contaminant.
  • the gas in reservoir 29 preferably is commercially pure argon, which has an oxygen concentration of less than 0.1 ppm.
  • Argon provides a clean environment by preventing other impurities from getting onto the blank.
  • argon has a higher density than air and, therefore, will remain in an uncovered compartment.
  • Other gases can be used if they are benign, i.e., will not react with the blank, and provide an environment in the compartment that is substantially devoid of oxygen, i.e., an amount of oxygen small enough to substantially inhibit passive oxidation.
  • commercially pure nitrogen which has an oxygen concentration of approximately 80 pnm, could be selected.
  • the gas in the compartment can be static or can flow through it. It is presently preferred to flow argon gas through the compartment at a constant flow rate of 0.5 to 1.0 standard liters per minute (slpm) . An appropriate flow rate can be chosen based on the particular gas selected.
  • FIG. 2 shows a preferred drawing device for use with the holding oven of the present invention.
  • the preferred drawing device is a conventional zirconia muffle furnace
  • the furnace 30 shown in FIG. 2 includes a drawing portion 32 for heating blank 20 to a fiber drawing temperature, which is typically about 2000°C.
  • the drawing portion 32 has a refractory, oxide component, which in the disclosed embodiment is a zirconia muffle 34 that distributes heat generated by a heating coil 36. Insulation 38 surrounds a portion of muffle 34.
  • the integrity of the environment in the drawing portion has been improved by providing a high temperature ceramic glue (CERAMABOND #503, Armco Products) that forms a gas-tight seal between a beaker top 40 and an upper muffle extension 42, and a flat, closed-cell silicone gask j 44 (Material No. 7204, Groendyk Mfg. Co.) that forms a gas-tight seal between a lower muffle extension 46 and an Elmer tube 48.
  • a high temperature ceramic glue CERAMABOND #503, Armco Products
  • a flat, closed-cell silicone gask j 44 (Material No. 7204, Groendyk M
  • a blank support rod 50 holds blank 20 in drawing portion 32.
  • An O-ring 52 forms a seal between a rod 50 and a sealing member 54, which is formed of metallic foil or the like. Sealing member 54 connects to an end cap 56, which itself is connected to an annular member 58.
  • the drawing device also has a supply device that supplies gas to the drawing portion to provide an environment in the drawing portion that causes active oxidation of the refractory contaminant and inhibits passive oxidation.
  • the supply device includes a pipe 60, which extends through annular member 58. Pipe 60 is connected to a gas supply 62 and supplies gas from gas supply 62 to the drawing portion 32.
  • Pipe 60 preferably flows gas through muffle 34 at a constant flow rate of 2 to 5 slpm.
  • the flow rate can be altered based on factors such as the flow :ate needed to maintain control of fiber attributes.
  • the environment of drawing portion 32 preferably causes active oxidation of the contaminants by providing a low concentration of oxygen.
  • the silicon carbide and silicon nitride contaminants corrode away due to active oxidation and are eliminated as break sources.
  • the gas supply 62 supplies a purge gas containing a reducing gas that reacts with oxygen to lower the oxygen concentration of the environment of the drawing portion 32.
  • the purge gas consists of helium (He) and carbon monoxide (CO) .
  • the carbon monoxide is a reducing agent that reacts with oxygen to produce carbon dioxide (C0 2 ) , thus reducing the oxygen concentration in the environment.
  • the gas supply 62 can be, for example, a reservoir of both helium and carbon monoxide or separate reservoirs of helium and carbon monoxide, the outputs of which are combined before or as they enter the draw furnace.
  • an external furnace that produces carbon monoxide by reaction and, therefore, renders unnecessary a reservoir of carbon monoxide.
  • Fig. 2 diagrammatically illustrates such an external furnace 71.
  • the external furnace 71 includes a reactive material 72 that reacts with at least a gas of a non-toxic gas mixture (provided by unillustrated gas reservoir ( s) ) to produce carbon monoxide.
  • the reactive material 72 can be a porous carbon or graphite material (such as a carbon honeycomb substrate manufactured by Corning Incorporated, e.g., part no. K2225) through which the non-toxic gas mixture can be passed.
  • the non-toxic gas mixture preferably contains helium and a reactive gas.
  • the reactive gas which can be, for example, carbon dioxide or oxygen, will react with the carbon material 72 to produce carbon monoxide.
  • the desired amount of carbon monoxide (preferably about 2% by volume) can be produced by manipulating th".
  • reactive gas concentration and the reaction temperature (the external furnace 71 preferably operates at atmospheric pressure) .
  • the reaction producing carbon monoxide is favored at high temperatures and low oxygen pressures.
  • thermodynamic equilibrium predicts that the CO:C0 2 ratio should be greater than 40:1. This ratio may be decreased if gas flow rates are fast enough to cause an incomplete reaction.
  • the typical flow rate or a zirconia draw furnace (4.5 slpm) is slow enough to ensure that the reaction is not kinetically limited. This is true when either carbon dioxide or oxygen is the reactive gas.
  • the external furnace 71 will preferably include a heating device.
  • the heating device can include a muffle 74 that distributes heat generated by a heating coil 76 to heat the gas to a preferred temperature of 1000°C.
  • the muffle 74 may be made with alumina, but car be any
  • S8BSTIT1ITE SHEET (RULE 28) material that will withstand relatively high temperatures and will not react with gas flowing through the external furnace 71.
  • the external furnace 71 can provide a purge gas containing carbon monoxide without the risks inherent in maintaining a reservoir of carbon monoxide.
  • the purge gas preferably contains only as much carbon monoxide as is necessary to provide an ox ,j en concentration that promotes active oxidation.
  • the amount of carbon monoxide required can be theoretically determined by, for example, calculating the amount of carbon monoxide required to cause P, ⁇ (after introducing carbon monoxide) to be greater than P 02 (before introducing carbon monoxide) .
  • Present zirconia muffle furnaces require approximately 2 to 5% carbon monoxide in the purge gas to meet this requirement.
  • the necessary amount of carbon monoxide can be determined by measuring the oxygen concentration in the drawing portion and adjusting the amount of carbon monoxide until the appropriate oxygen concentration is achieved. It is presently contemplated that a delta-F electrolyte detector can be used to measure the oxygen concentration in the drawing portion.
  • a conventional drawing mechanism (not shown) can be used to draw a fiber from the blank in the environment in the drawing portion.
  • FIG. 6 The second embodiment of a holding oven according to the present invention is shown in FIG. 6 and is designated generally by reference numeral 110.
  • gas flows through the holding oven 110 at a rate sufficient to prevent an environmental contaminant, such as particulate zirconium compounds or calcium compounds, from becoming attached to the surface of the blank 20 and, preferably, to dislodge an environmental contaminant that was lodged on the surface of the blank 20 before initiating the flow of gas.
  • an environmental contaminant such as particulate zirconium compounds or calcium compounds
  • the holding oven 110 includes a compartment 112 for storing the blank 20.
  • the compartment 112 includes a muffle 114, which is gripped and supported by clamps 115.
  • a top seal 18 and a cover 22 cover the top of the muffle 114, and a handle 24 extends through the cover 22 to hold the blank 20.
  • Heaters and insulation 26 maintain the compartment 112 at an appropriate temperature.
  • the holding oven 110 also includes a supply device 162 that supplies gas to the compartment 112.
  • the supply device 162 preferably includes a nozzle device 163 having a rubber O-ring seal 166, a metal top ring 164, a rubber O-ring seal 167, a glass plate 168, a rubber O-ring seal 170, and a metal bottom ring 172.
  • Bolts 174 urge the top and bottom rings 164 and 172 toward each other.
  • the supply device 162 also includes a pipe system 128 that supplies gas from a reservoir 129 to orifices 165
  • SUBSTITUTE SHEET (RULE 28) disposed at spaced locations in the top ring 164 (FIG. 7) .
  • the gas in the reservoir 129 preferably is commercially pure nitrogen, although other benign gase- such as argon can be used.
  • the gas supplied by the supply device 162 flows through the compartment 112, against a surface of the blank 20, and out of the compartment 112 through a gap 23 between the cover 22 and the handle 24.
  • the gas flows along the longitudinal direction of the blank 20, as shown by arrows in FIG. 6.
  • the supply device 162 supplies the gas to the compartment 112 at a rate sufficient to prevent an environmental contaminant from becoming at t ached to the surface of the blank 20.
  • the flowing gas forms a curtain that substantially prevents environmental contaminants in the compartment 112 from contacting the surface of the blank 20.
  • the gas should, of course, be free of environmental contaminants so it will not introduce such contaminants into the compartment 112.
  • the supply device 162 supplies the gas to the compartment 112 at a rate sufficient to dislodge an environmental contaminant that was lodged on the surface of the blank 20 before initiating the flow of gas. If the gas i'. flowed at a sufficient rate, the force of the gas will overcome the adhesion of the environmental contaminant to the blank
  • SUBSTITUTE SHEET (RUIE2(!) (e.g., as by static charge) and dislodge the environmental contaminant from the surface of the blank 20.
  • the gas will also prevent the environmental contaminant from resettling on the surface of the blank 20.
  • flowing gas through the compartment 112 at a constant flow rate of 10 to 15 slpm should be sufficient to prevent most particulate contaminants from becoming attached to the surface of the blank 20 and should also be sufficient to dislodge most particulate contaminants that may initially be lodged on the surface of the blank 20.
  • a constant flow rate of 30 slpm is presently preferred ' because such a high flow rate will better ensure removal of environmental contaminants from the surface of the blank 20.
  • a particular flow rate for a specific environment can be readily deterrr ned by one of ordinary skill in the art.
  • the average number of breaks per kilokilometer (kkm) in fiber drawn from the blanks that had been stored in the conventional holding oven was more than twice the average number of breaks per kkm in fiber drawn from the
  • the present embodiment can create an environment in the compartment 112 that inhibits passive oxidation of a refractory contaminant of the blank 20, such as silicon carbide or silicon nitride, in accordance with the principles described in connection with the first embodiment of the invention.
  • SUBSTITUTE SHEET (RULE 28) reference to environmental contaminants of particulate zirconia and calcium compounds, the invention may be used for other environmental contaminants.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (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)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)
  • Inorganic Fibers (AREA)
  • Preliminary Treatment Of Fibers (AREA)
  • Manufacture, Treatment Of Glass Fibers (AREA)

Abstract

Une ébauche de fibre (20) est contaminée par des contaminants tels que du nitrure de silicium ou du carbure de silicium. Une telle ébauche séjourne dans une chambre (10) à l'intérieur de laquelle est introduit un gaz réducteur (29). Ce gaz réducteur empêche l'oxydation des contaminants. Si ces derniers subissaient une oxydation, la résistance de la fibre résultante s'en trouverait réduite.
PCT/US1997/018041 1996-10-25 1997-10-03 Appareil et procede pour reduire la fracture des fibres etirees a partir d'ebauches WO1998018733A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
CA002267970A CA2267970A1 (fr) 1996-10-25 1997-10-03 Appareil et procede pour reduire la fracture des fibres etirees a partir d'ebauches
EP97910815A EP0963356A4 (fr) 1996-10-25 1997-10-03 Appareil et procede pour reduire la fracture des fibres etirees a partir d'ebauches
JP52049298A JP2001507663A (ja) 1996-10-25 1997-10-03 ブランクから引き伸ばされたファイバの破損を減少させる装置および方法
AU48095/97A AU734480B2 (en) 1996-10-25 1997-10-03 Apparatus and method for reducing breakage of fibers drawn from blanks

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US2931896P 1996-10-25 1996-10-25
US60/029,318 1996-10-25

Publications (1)

Publication Number Publication Date
WO1998018733A1 true WO1998018733A1 (fr) 1998-05-07

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PCT/US1997/018041 WO1998018733A1 (fr) 1996-10-25 1997-10-03 Appareil et procede pour reduire la fracture des fibres etirees a partir d'ebauches

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EP (1) EP0963356A4 (fr)
JP (1) JP2001507663A (fr)
AU (1) AU734480B2 (fr)
CA (1) CA2267970A1 (fr)
WO (1) WO1998018733A1 (fr)

Cited By (6)

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Publication number Priority date Publication date Assignee Title
EP1033321A2 (fr) * 1999-02-24 2000-09-06 Shin-Etsu Chemical Co., Ltd. Emballage et procédé d'emballage de préformes en verre
EP1050516A1 (fr) * 1999-05-06 2000-11-08 Lucent Technologies Inc. Procédé d étirage d une fibre optique en réduisant les défauts causés par des particules et préforme pour l utilisation dans le procédé
WO2001030712A1 (fr) * 1999-10-28 2001-05-03 Corning Incorporated Procede de protection d'une preforme creuse pour fibres optiques
US6546756B1 (en) 1999-12-27 2003-04-15 Corning Incorporated Method of making an optical fiber, with storage in a new bag
US6813908B2 (en) 2000-12-22 2004-11-09 Corning Incorporated Treating an optical fiber preform with carbon monoxide
US7089766B2 (en) 2000-04-28 2006-08-15 Corning Inc Method of forming optical fiber preforms

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US4854956A (en) * 1986-07-14 1989-08-08 U.S. Philips Corp. Method of manufacturing optical fibres having a core and a cladding of glass applying the rod-in-tube technique

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1033321A2 (fr) * 1999-02-24 2000-09-06 Shin-Etsu Chemical Co., Ltd. Emballage et procédé d'emballage de préformes en verre
EP1033321A3 (fr) * 1999-02-24 2001-03-14 Shin-Etsu Chemical Co., Ltd. Emballage et procédé d'emballage de préformes en verre
US7093412B1 (en) 1999-02-24 2006-08-22 Shin-Etsu Chemical Co., Ltd. Glass base material packing method
EP1050516A1 (fr) * 1999-05-06 2000-11-08 Lucent Technologies Inc. Procédé d étirage d une fibre optique en réduisant les défauts causés par des particules et préforme pour l utilisation dans le procédé
US6189341B1 (en) 1999-05-06 2001-02-20 Lucent Technologies Inc. Method of making an optical fiber with digestion of retracting particles on the preform
WO2001030712A1 (fr) * 1999-10-28 2001-05-03 Corning Incorporated Procede de protection d'une preforme creuse pour fibres optiques
US6266980B1 (en) 1999-10-28 2001-07-31 Corning Incorporated Centerline protection using heavy inert gases
US6546756B1 (en) 1999-12-27 2003-04-15 Corning Incorporated Method of making an optical fiber, with storage in a new bag
US7089766B2 (en) 2000-04-28 2006-08-15 Corning Inc Method of forming optical fiber preforms
US6813908B2 (en) 2000-12-22 2004-11-09 Corning Incorporated Treating an optical fiber preform with carbon monoxide

Also Published As

Publication number Publication date
EP0963356A4 (fr) 2000-06-14
AU734480B2 (en) 2001-06-14
AU4809597A (en) 1998-05-22
JP2001507663A (ja) 2001-06-12
CA2267970A1 (fr) 1998-05-07
EP0963356A1 (fr) 1999-12-15

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