PROCESS FOR PRODUCING OPTICAL FIBER BASE AND APPARATUS THEREFOR

摘要

A process for producing an optical fiber base in which a porous glass base can be dehydrated and sintered without fouling or damaging it; and an apparatus for the process. The process for optical fiber base production is characterized by comprising: a porous-glass-base formation step in which fine glass particles are accumulated to form a porous glass base; a vessel preparation step in which a vessel is prepared which employs a composite tube comprising a synthetic-quartz glass tube formed from a melt of a soot accumulation obtained by accumulating fine glass particles yielded by hydrolyzing a silicon compound with an oxyhydrogen flame and a natural-quartz glass tube formed from natural quartz melted with an electric furnace, the former glass tube being jacketed with the latter glass tube; a gas introduction step in which a dehydrating reactant gas and an inert gas are introduced into the vessel; a heating step in which the vessel having the dehydrating reactant gas and inert gas introduced therein is heated; and a dehydration/sintering step in which the porous glass base is inserted in the heated vessel and then dehydrated and sintered therein.