Process for producing a glass preform for an optical fiber and apparatus for the same

摘要

The present invention relates to a process for producing a porous glass preform for an optical fiber and an apparatus for conducting such a process. According to the process, fine glass particles are produced by heating and reacting vaporous starting materials in a reaction vessel. The resulting fine glass particles are thereafter deposited to obtain the porous glass preform. An exhaust gas containing non-deposited fine glass particles is exhausted through an exhaust duct at a velocity above 15 m/sec. Preferably, pressure fluctuation in the reaction vessel is minimized by supplying air from outside of the reaction vessel to the exhaust duct. In accordance with the present invention, the exhaust duct is less likely to become obstructed by non-deposited fine glass particles. As a result, the preform can be produced without interruption over an extended period of time.