PRODUCTION OF OPTICAL FIBER PREFORM

摘要

PURPOSE:To provide the method for producing an optical fiber preform so that rare earth elements may be uniformly distributed in the radial direction thereof. CONSTITUTION:The whole parent material 15 composed of a porous glass is immersed in a solution prepared by dissolving erbium chloride in ethyl alcohol and allowed to stand for about 2hr to sufficiently impregnate the parent material 15 composed of a porous glass with the solution. The parent material 15 composed of a porous glass is subsequently pulled out of the solution surface at a rate of about 5mm/min. While pulling up the parent material 15 composed of a porous glass, the solvent contained therein is evaporated by a hot air heated by a heater 13 and the parent material 15 composed of a porous glass is dried. Sintering is then carried out to form a transparent glass, thus obtaining the objective an optical fiber preform.