The method of making blanks for fibers based on silica glass
(57) Abstract:The method used for the production of elements of fiber-optic communication lines (fiber collimators radiation devices docking fiber, spectral filters, optical isolators and sensors of physical quantities. To increase the occurrence of nitrogen in a quartz glass to the level required to provide the required difference n the refractive indices of the core and the shell, the support tube serves a mixture of molecular gas reagents containing atoms of nitrogen, oxygen and silicon. Molecular gas reagents are mixed so that each silicon atom has no more than five atoms of oxygen, and for every 1000 atoms of oxygen have at least 1 nitrogen atom. In the support tube excite the microwave discharge. The products flowing in the reaction mixture are deposited on the inner surface of the support tube. 4 C.p. f-crystals, 1 Il. The invention relates to fiber optics, in particular to the production technology of optical fibers, and is industrially applicable in fiber-optic communication lines, fiber collimators radiation devices docking fiber, the spectral filters, opticare glass, doped with germanium (Optical communication systems). Gower, English Translation edited by A. Larkin, I. - M.: Radio and communication, 1989, S. 98). Germanium is introduced into the glass core of the fiber to increase the refractive index of the glass and thereby create radial profile of the refractive index with the maximum in the core. The drawback of such optical fibers is a relatively high cost of Germany and insufficient radiation resistance of germanium silicate glass. The latter circumstance does not allow to use germanium-silicate optical fibers in conditions of high radiation background.Known fiber optic cable in which the core consists of undoped quartz glass, and as the shell of the use of quartz glass with a lower refractive index, for example, doped with fluorine (Biryukov, A. C., K. Golant M, Dianov E. M., Corobov Century A., shahani A. C. high-purity substances, No. 1, 1992, S. 19). Such fibers more radiation rack. Their disadvantage, however, is repressirovannaya structure of the refractive index, which makes the light-sensitive microshell and therefore is a source of additional optical loss. To minimize such losses required great technology billets.Known fiber optical fibers based on silica glass doped with nitrogen (V. A. Bogatyrjov, E. M. Dianov, K. M. Golant, R. R. Khrapko, A. S. Kurkov, Silica fibers with silicon oxynitride core fabricated by plasmachemical technology, OFC'95, San Diego, California, Technical Digest, vol. 8, p. 266). They combine the radiation resistance, which is close to the optical fibers with pure silica core and a fluorine-silicate shell, and the structure of the refractive index without depression characteristic of germanium-silicate fiber light guides. Their advantage is the absence of expensive alloying elements in the composition of quartz glass. Numerical aperture and the associated positive effect achieved by the use of such fibers is greater, the greater the concentration of nitrogen.The known method for manufacturing of optical fibers based on silica glass, including serving in a support tube of a mixture of molecular gas reagents contain oxygen atoms and silicon and the deposition of products flowing in the reaction mixture on the inner surface of the support tube (Handbook of fiber optic communication lines / Andrushko L. M., ascension Century A., Rink Century B. and others edited Svechnikova S. and Andrushko L. M. - Kyiv: Tekhnika, 1988, S. 69). The disadvantage of this speechmikes decision to declare a known method of manufacturing preforms for fiber based on silica glass, doped with nitrogen, including serving in a support tube of a mixture of molecular gas reagents containing atoms of nitrogen, oxygen and silicon, the excitement in her microwave discharge and precipitation products flowing in the reaction mixture on the inner surface of the support tube (E. M. Dianov, K. M. Golant, R. R. Kharpko, A. S. Kurkov, A. L. Tomashuk. Lowhydrogen silicon oxynitride optical fibers prepared by SPCVD. IEEE Journal of Lightwave Technology, 1995, vol. 13, No. 7, pp. 1471-1474). It is based on the formation of the core of the fiber preform by chemical synthesis layers of silica glass doped with nitrogen, on the inner wall of the support tube made of quartz glass by SPCVD technology (patent France Monique Moisan, Dominique Pavy, Marie Eve Davoust, Serge Saada, Patrick Chollet N 2628730, Dispositif de fabrication de preformes pour fibre optiques, class C 03 B 37/018, publ. 1988).The disadvantage of the prototype is that it does not define the ratio of silicon to oxygen entering the reactor, the gas mixture. This makes it impossible according to the prototype to ensure that the process mode of occurrence of nitrogen in a quartz glass to obtain a given refractive index difference between the core and the shell n.With the help of the claimed invention solves the problem of finding a technological regime is required to ensure="ptx2">The problem is solved in that in the known method of manufacturing preforms for fiber based on silica glass doped with nitrogen, including serving in a support tube of a mixture of molecular gas reagents containing atoms of nitrogen, oxygen and silicon, the excitement in her microwave discharge and precipitation products flowing in the reaction mixture on the inner surface of the support tube, molecular gas reagents supplied in the supporting tube, mix so that each silicon atom has no more than five atoms of oxygen, and for every 1000 atoms of oxygen have at least 1 nitrogen atom.In particular, as a mixture of molecular gas reagents used at least one of the mixtures SiCl4+ O2+ N2, SiCl4+ O2+ NO2, SiCl4+ O2+ N2O3, SiCl4+ O2+ N2O4, SiCl4+ O2+ N2O, SiCl4+ O2+ NO and/or SiCl4+ O2+ NH4.In particular, the temperature of the support tube is 900 - 1300oC; the power required for excitation in the support tube of the microwave discharge is 0.1 - 10 kW; pressure molecular gas reagents inside the supporting MESI molecular gas reagents inside the supporting tube increases the nitrogen content in the blanks and, the result is the desired value of n.the drawing shows a device that implements the inventive method.The drawing shows a reference quartz tube 1, a mixture of molecular gas reagents 2, the area of deposition 3, the microwave power 4 supplied through waveguide 5 in the annular gap 6, the surface plasma wave 7, the matching device 8 with the piston and the plasma column 9.The molecular gas mixture of reagents 2 arrives in the support tube 1 made of quartz glass under pressure of several mm RT.article On the opposite side to the tube is supplied microwave power of 4, under the action of which in the mixture is maintained stationary discharge, forming a plasma column 9. As reagents 2 use the dried oxygen and nitrogen with silicon tetrachloride. Reagents 2, falling into the region of the plasma column 9, experiencing chemical transformations due to the appearance in the mixture of active radicals, which are "acquired" in a mixture of unexcited molecules during their interaction with the "hot electrons" plasma. As a result, the silicon tetrachloride is converted into silicon oxide, which is adsorbed by the walls of the support tube and doukissis in the heterogeneous reaction with usuarios glass. Changing the length of the plasma column 9 by changing the applied microwave power of 4, you can implement the scanning mode of the deposition zone 3 along the support tube 1 and thereby to carry out the mode layer-by-layer deposition of glass on the inner surface.For the manufacture of wood fiber fiber with a cladding of undoped quartz glass, the core glass doped with nitrogen, and the value n=0,02 support tube 1 with a diameter of 20 mm and a wall thickness of 2 mm is heated to a temperature of 1250oC. In the support tube 1 serves a mixture of 2 composition SiCl4+O2+N2with the full pressure of 1 mm RT.article Microwave power 4 change in the range of 1 to 5 kW. The desired doping level glass nitrogen is obtained when the mass ratio of expenses [SiCl4] :[O2] = 0.92 and [O2]:[N2] = 0,5. When this attitude coming into the reactor per unit time of oxygen atoms and silicon is 2.2, and nitrogen and oxygen is - 2.For the manufacture of wood fiber fiber with a cladding of undoped quartz glass, the core glass doped with nitrogen, and the value of n=0.01 to the support tube 1 with a diameter of 20 mm and a wall thickness of 2 mm is heated to a temperature of 1250oC. In the support tube 1 pod is e 1 - 5 kW. The desired doping level glass nitrogen is obtained when the mass ratio of expenses [SiCl4]:[O2]=0,76 and [O2]:[N2]=0,5. When this attitude coming into the reactor per unit time of oxygen atoms and silicon is 2.6, and nitrogen and oxygen is - 2.Thus, examples of specific performance indicate the solution of the problem. 1. The method of making blanks for fibers based on silica glass doped with nitrogen, comprising heating the support tube, the flow in the reference tube molecular gas mixture of reagents containing atoms of nitrogen, oxygen and silicon, the excitement in her microwave discharge and precipitation products flowing in the reaction mixture on the inner surface of the support tube, wherein the molecular gas reagents supplied in the supporting tube, mix so that each silicon atom has no more than five atoms of oxygen, and for every 1000 atoms of oxygen have at least one nitrogen atom.2. The method according to p. 1, characterized in that as the molecular gas mixture of reagents used at least one of the mixtures SiCl4+O2+N2, SiCl4+O2O, SiCl4+O2+NO and/or SiCl4+O2+NH4.3. The method according to p. 1, characterized in that the molecular gas mixture flow of reagents in the support tube, it is heated to 900 - 1300oC.4. The method according to p. 1, characterized in that the power required for excitation in the support tube of the microwave discharge is 0.1 - 10 kW.5. The method according to p. 1, characterized in that the gas pressure of the reactants inside the supporting tube is 0.05 - 50 mm RT.article
FIELD: optical fibers production techniques.
SUBSTANCE: the invention is dealt with optical fibers production techniques. For production of optical fiber billets particles of a glass first are synthesized in the oxygen-hydrogenous torch flame. Production a porous billet is made by settling the particles in a radial direction on the external surface of the parent element with following sintering of the porous billet. At that definite ratio between the speed of flow of a starting gaseous material or a gas mixture consisting of the starting gaseous material and an additive gas and a speed of flow of a noble gas should be maintained. The torch has four channels for feeding of gases. The sizes of channels of the torch ensure the definite ratio of the indicated speeds.
EFFECT: The invention ensures an increase of quality of the optical fiber billets.
4 cl, 2 dwg
FIELD: methods of optical fibers production.
SUBSTANCE: the invention is pertaining to the methods of production of optical fibers and may be used in production of quartz fiber light guides. The device represents installed on a frame in a protective jacket following components: a mandrel and a holder, a unit of rotation and reactor of spraying. On the frame also there are guides and the lower mobile platform. The second guides limited from above by a small frame are fixed on the upper base of the frame. On the second guides there are two more fixed mobile platforms. All three platforms are coupled by a common combined shaft enabling the platforms to move synchronously or with different ratios of speeds. One of the mobile platforms - the upper one - is mounted on the upper part of the frame and contains an assembly of fixation of the mandrel and the holder, one of the bases of which has the form of a polyhedron and contacts to the unit of rotation; another platform is supplied with a dehydration furnace. The protecting jacket is made in the form of a couple of the flutes mounted on the both sides of the upper platform and consists of two parts of the similar volume. The similar jacket is fixed on the lower mobile platform and has a docking unit of coupling with the reactor of spraying or with a glazing furnace. The invention ensures an increase of the final length of the light guides and an increased yield of the product.
EFFECT: the invention ensures an increased final length of the light guides and the increased yield of the product.
FIELD: fiber-optic communication; medicine; opto-and- microelectronics; methods of production of quartz blanks of the fiber light guides.
SUBSTANCE: the invention is pertaining to the methods of production of quartz blanks of fiber light guides by a deposition from a gas phase and may be used in various systems of a fiber-optic communication, medicine, opto-and- microelectronics. The method is based on a deposition of layers of a shell and a core on an exterior surface of a support quartz pipe made out of engineering quartz glass, which in the further is etched out in the process of a collapse into a stud-plank in the result of passing through it of a mixture of the chemically reactive gases (for example, SF6) with oxygen. At that the support quartz pipe is tightly set on a metal pipe forming a metal-dielectric wave-guiding structure necessary for excitation and propagation along it of an UHF-discharge on a surface wave. Relocation of the front of the UHF-discharge is carried out by modulation of the fed to the metal-dielectric wave-guiding structure of the UHF-power. The method ensures a capability of shaping of blanks of the light guides practically of any types and compositions, and also allows to refuse the high-quality and high-expensive quartz pipes, to reduce the prime cost of the produced blanks, to increase the factory length of the light guides due to an increase of diameter of molded blank.
EFFECT: the invention allows to shape the light guides blanks of any types and compositions, to refuse the high-quality and high-expensive quartz pipes, to reduce the prime cost of the produced blanks, to increase their factory length.
FIELD: optical engineering.
SUBSTANCE: single-mode optical fiber has light-conducting part (4) of core, internal part (3) of envelope which surrounds part 4 of core and area of coating which surrounds the internal part (3) of envelope. Refractivity factor of core part 4 excesses refractivity factors of area 1 and 3 of envelope which are almost equal. Internal part (3) of envelope is made of SiO2 which includes doping fluoride in amount of 0,1-8,5 mass percent which results to compressing axial force of part 4 of core along its whole cross-section. Internal part 3 of envelope is additionally provided with doping additives to increase refraction and to get refractivity factor being practically equal to refractivity factor of area 1 of coating. Tube base is made of silicon dioxide and the base functions as area of coating. Internal part of envelope and area of core are formed by means of one or several reaction-capable gases. After they are formed the tube of base is subject to shrinkage and elongation to single-mode optical fiber. Single-mode optical fiber produced has low hydrogen-induced attenuation at 1500 nm wavelength.
EFFECT: lower hydrogen-induced attenuation.
15 cl, 8 dwg
FIELD: fiber optics; manufacture of single-mode fiber light conduits at high double refraction used in information transmission systems and interferometric sensors of physical fields.
SUBSTANCE: proposed method increases ellipticity of straining envelope and high-temperature treatment of blanks. Proposed method includes obtaining blanks of fiber light conduits by application on inner surface of quartz tube layers of quartz glass alloyed with P2O5 together with fluorine by chemical vapor-phase deposition method, straining envelope, insulating envelope and layer of core, collapsing tube into molding fillet, abrasive treatment of diametrically opposite outer sides of blank-molding fillet by cutting symmetrical grooves along axis over entire length, 0.3-1 mm deep at depth sufficient for penetration in layer of protective envelope so that gap between bottom of groove and straining envelope is formed; then it is subjected to holding in hydrofluoric acid solution till width of groove in layer of protective envelope increases by 2-2.5 times after which blank is subjected to rounding and light conduits are drawn. Prior to drawing light conduits, blanks shall be annealed in air atmosphere at temperature of 900-1000°C for 4-10 h.
EFFECT: enhanced retaining of radiation polarization; reduced optical losses of light conduits.
2 cl, 2 dwg, 1 ex
FIELD: glass industry; methods of manufacture of the optical glass.
SUBSTANCE: the invention is pertaining to the field of glass industry, in particular, to the method of manufacture of the optical glass. The invention provides that the number of the remained bubbles with the diameter of 0.3 mm and more makes 0.005 pc/cm3 or less per the unit of the volume of the optical glass. Such optical glass is produced at regulation of the temperature of the torch butt surface for the synthesis of glass In the process of deposition of the glass particles by regulation of the ratio of the speed of the flow or the volume of the flow between the combustible gas and the gas, which is sustaining combustion. The technical problem of the invention is prevention of destruction of the torch used for the synthesis of the optical glass and provision of manufacture of the optical glass of the stable quality.
EFFECT: the invention ensures prevention of destruction of the torch used for the synthesis of the optical glass and provision of manufacture of the optical glass of the stable quality.
4 cl, 4 ex, 4 dwg
FIELD: glass industry; methods of production of the optical fibers used for the high-speed data transmission.
SUBSTANCE: the invention is pertaining to the field of glass industry, in particular, to the method of manufacture of the optical fibers used for the high-speed data transmission. The method includes the following stages: i) feeding of one or several source substances for production of the glass and possibly the additive compound in the quartz tube-substrate; ii) creation of the plasma in the quart tube-substrate for provision of the reaction in the chemically active mixture for production of the glass layers, which may include or not include the additive compound on the internal side of the tube-substrate; iii) the collapse of the tube-substrate produced at the stage ii) into the billet at heating; iv) drawing the optical fiber from the billet at heating. The glass layers are settled on the section having the greatest diameter of 10 microns in the center of the drawn optical fiber. At least one of the indicated layers has the greatest area of the surface of 2 micron2, and the value of the index of refraction inside each layer is increasing in the direction to the center of the fiber. The technical result of the invention is development of the optical fiber capable to transmit information with the speed exceeding 1 Gigabit per a second.
EFFECT: the invention ensures development of the optical fiber capable to transmit the data with the speed exceeding 1 gigabit per a second.
9 cl, 1 tbl, 4 ex
FIELD: production of fiber-optic light conduits.
SUBSTANCE: proposed method includes settling of glass-forming oxides on seed bead by delivery of vapor-gas mixture of halogenides of respective elements to flame of burner which moves along bead. Vapor-gas mixture is fed to circular clearance between seed bead and tube located coaxially relative to it and mounted together with burner on movable support of machine. Tube moves in synchronism with burner and vapor-gas mixture is fed at angle of 10-60° to axis of seed bead. Width of circular clearance is set between 0.8D and 1.5D, where D is diameter of jet of vapor-gas mixture at circular clearance inlet; length of tube is set between 10h and 30h, where h is width of circular clearance.
EFFECT: enhanced efficiency of settling of aerosol oxides on blank of fiber-optic light conduit.
FIELD: glass industry; methods of manufacture of the optic fibers.
SUBSTANCE: the invention is pertaining to glass industry, in particular, to the method of manufacture of the optic fiber. The offered method of manufacture of the optic fiber is pertaining to field of production of the fiber light guides used in the optical cables for transmission of information. The technical result of the invention is simplification of the process of manufacture of the optic fiber, decrease of the dimensions of the fibers and the optical cable. The purpose of the presented method is production of the light guide cladding and the light guide core by irradiation of the blank of the optic fiber made out of the homogeneous chemical substance, predominantly - silicon dioxide, with the neutron flux with the strictly set depth of their absorption.
EFFECT: the invention ensures simplification of the process of manufacture of the optic fiber, the decreased dimensions of the fibers and the optical cable.
8 dwg, 2 tbl
FIELD: glass industry; other industries; methods and the devices of production of the optical fibers.
SUBSTANCE: the invention presents the method and the device for manufacture of the billet of the optical fiber with usage of the simultaneous plasma deposition on the internal and external surfaces of the initial tube. At rotation of the initial tubular element conduct the selective injection of the chemicals in the plasma torch and the chemicals flowing through the cavity of the tube. The plasma torch is moved along the tubular element for the simultaneous deposition of the carbon-black on the internal and external surfaces. The carbon-black on one or both surfaces can be condensed into the layer of quartz glass after its deposition. Then the plasma torch again is moved for deposition of the additional carbon-black and-or for consolidation of the before deposited carbon-black on one or both surfaces. The process is repeated until enough silicon dioxide is deposited on the tubular element. After that the tubular element is flattened. The additional plasma deposition can be made during this flattening or after it. The technical problem of the invention is to increase productivity at production of the billets of the optical fibers and the fibers of the big diameter.
EFFECT: the invention ensures the increased productivity at production of the billets of the optical fibers and the fibers of the big diameter.
35 cl, 7 dwg