Method and apparatus for manufacturing of silica optical Fuaiba

摘要

PURPOSE: To efficiently obtain a silica optical fiber doped with a metal oxide by combining a supporting tube which forms silica powder by bringing low- vapor-form reactants and an inner tube which forms the vapor of a metal halide to be used as a doping agent in a specific composition. ;CONSTITUTION: This apparatus has the supporting tube TQ and the silica and doping agent are generated by the reaction between the vaporform reactors in this tube TQ and are deposited on the inside surface of the supporting tube. The tube TQ is rotated around its axis by two joints consisting of stationary parts FA, FB and rotating parts RA, RB (one thereof is for reactant injection and the other is for depleted gas discharge). The apparatus has a heat source which encloses the annular area of the supporting tube TQ and is movable in an axial direction). The inner tube TD is arranged in the axial position in the supporting tube TQ and the diameter thereof is fairly smaller than that of the supporting tube TQ. The inner tube, has a slit FE. The length of the slit is equal to that of the silica deposition area and the width thereof increases in the direction of the flow of the gaseous mixture arriving from the outer side in the inner tube TD. High-purity wool MA of the metal to be the desired oxide is packed into the inner tube TD.;COPYRIGHT: (C)1990,JPO