Method of producing a rod containing fluorine.

摘要

A method for producing an optical fiber preform (1) comprising injecting a glass raw material, a gaseous fluorine-containing material and oxygen gas from a first nozzle, (3) inactive gas from a second nozzle (4) which surrounds the first nozzle (3) and hydrogen gas from a third nozzle (5) which surrounds the second nozzle (4), flame hydrolyzing the glass raw material to synthesize fine glass particles and depositing the fine glass particles on a tip of a rotating seed rod to produce the optical fiber preform (1) containing fluorine.