Method for sintering a porous-glass preform for an optical fibre

摘要

A method for sintering a porous-glass material (12) to form a glass base material, which is a base material for an optical fiber, comprising: preparing a ring heater (26) having an opening, through which the porous-glass material (12) passes, for heating the porous-glass material (12); selecting the porous-glass material (12) having an outer diameter (d) within a predetermined range, the predetermined range being determined based on an inner diameter (D) of the opening of the ring heater (26) ; and heating the porous-glass material (12) in an atmosphere of dehydration gas and inert gas with the ring heater (26).