METHOD FOR PRODUCING GLASS PREFORM FOR OPTICAL FIBER

摘要

The present invention relates to a glass preform for use in fabrication of an optical fiber having no residual bubbles. The glass preform is produced by depositing glass soot on a periphery of a starting glass rod to form a porous glass preform, heating and sintering the preform in a helium atmosphere to consolidate the preform and then heating the sintered glass in an atmosphere containing an inert gas, except helium, having a partial pressure of the inert gas of not lower than 0.8 atm. A transparent glass preform is thereby obtained.