A method for producing a glass particulate deposit, said method comprising using siloxane as a raw material for glass, discharging the siloxane gasified in a vaporizer and a combustion gas from a burner and combusting, and thus forming a glass particulate deposit in a reaction vessel, wherein: after producing a good section of the glass particulate deposit, the supply of the siloxane that is the raw material for glass to the burner is ceased while continuously supplying the combustion gas to the burner; then the glass particulate deposit is taken out from the reaction vessel; a raw material gas port from the vaporizer to the burner is purged by flowing an inert gas therethrough; and, when a color derived from the combustion of the siloxane gas is not observed any more in the flame of the burner, then the supply of the combustion gas is ceased.

An apparatus for manufacturing glass preforms for optical fibers includes a reaction chamber surrounding a deposition region, a holding device for holding a target rod within said deposition region, one or a plurality of deposition burners positioned below said deposition region and configured to direct a high temperature flow of forming glass particles toward said target rod, a hood positioned opposite to the deposition burners with respect to said holding device and configured for discharging soot of un-deposited glass particles, said hood including at least one exhaust port provided at a first end portion thereof and side panels extending from a second end portion thereof toward said first end portion. At least a portion of the side panels of the hood is gas permeable.

A method for manufacturing an optical fiber preform includes: producing a core preform including a core portion made of transparent glass and a first cladding layer obtained by adding fluorine to the core portion; and forming, on an outer periphery of the first cladding layer, a second cladding layer made of glass having a refractive index higher than that of the first cladding layer. Further, a refractive index profile is formed in the first cladding layer due to a fluorine concentration profile, the refractive index profile being provided at least near a boundary surface with the second cladding layer and having a profile such that a refractive index difference between a refractive index of the first cladding layer and a refractive index of the second cladding layer decreases in accordance with a reduction in a distance from the boundary surface with the second cladding layer.

A method for processing strands of optic fiber in which a box containing one or more pairs of wheels either crush, cut or bend and break the strands of optic fiber before being transported to a separator. The separator can be positioned to deposit material onto a conveyor belt, into a storage container or into a separate structure known as a step-cleaner. The box can contain a pair of cutting and anvil wheels, a pair of drive wheels or a pair of wheels featuring teeth that cut, crush or bend the strands of optic fiber prior to a suction force removing them from the box and transporting them to the separator. A step cleaner contains one or more rotating wheels with tines that agitate and move the cut, broken or crushed fibers. The suction force is created by a blower operably connected to a passage that communicates with the separator.

To provide a fabrication method for a porous glass base material for optical fiber, the method including performing deposition of glass fine particles generated by using a burner for glass fine particle synthesis to form a porous glass base material, and heating this porous glass base material to be transformed into transparent glass to obtain a glass base material hardly containing any air bubbles. Provided is a fabrication method for a porous glass base material for optical fiber by depositing glass fine particles, which is generated in flame formed by ejecting a glass raw material gas and a combustible gas from a burner, on a rotating starting material, in which the burner continuously ejects inert gas for at least a predetermined period immediately after the end of the deposition of the glass fine particles.

The present disclosure provides a method for modification of surface of an initial optical fiber preform. The initial optical fiber preform is manufactured using at least one preform manufacturing process. The surface of the initial optical fiber preform is treated with 50-70 liters of chlorine per square meter of the surface of the initial optical fiber preform. The surface of the initial optical fiber preform is flame polished using a flame polishing module. The treatment of the surface of the initial optical fiber preform with chlorine and flame polishing of the surface of the initial optical fiber preform collectively converts the initial optical fiber preform into a modified optical fiber preform.

A manufacturing apparatus for an optical fiber porous preform includes a reaction chamber configured to accommodate a starting material; at least one main burner provided in the reaction chamber, the at least one main burner being configured to be supplied with a gas containing at least a source gas and a flammable gas, such that particulates are to be generated from reaction of the source gas and the flammable gas and deposited on the starting material; at least one auxiliary burner configured to be directed toward an end portion of the starting material on which the particulates are to be deposited; and an airflow guide provided such that at least part of the airflow guide is located across the at least one auxiliary burner from the starting material.

An optical fibre, for use in the field of distributed measurement of temperature or deformation by optical reflectometry in the frequency domain using the Rayleigh backscattered signal in the fibre, includes a core doped with nanoparticles for example formed from gold particles covered with zirconium oxide, and can be subjected to high temperatures during the measurement. A method for producing the optical fibre includes a step of heat treatment during which the optical fibre is subjected, for a duration of at least one hour, to a heat treatment temperature higher than a maximum temperature to which it will be subjected during a measurement.

This burner for producing a fine glass particle deposited body is provided with a metallic gas-feed pipe that forms a burner body, and a cover for covering the gas-feed pipe, wherein: the gas-feed pipe and the cover are integrally formed; the gas-feed pipe has connected thereto a piping through which material gas, oxyhydrogen gas, and seal gas are supplied; and the cover covers, in the axial direction of the burner over a prescribed length and in a given constant outer diameter, the gas-feed pipe and a connection part of the piping connected to a lateral surface of the gas-feed pipe.

A lathe system for producing an optical fiber preform, the lathe system including a rotating bait rod, a burner box configured to deposit silica-containing soot on the rotating bait rod, a hood configured to direct airflow within the lathe system through an exhaust, and a perforated floor configured to expel air within the lathe system as a plurality of air jets from a bottom portion of the lathe system to a top portion of the lathe system.