BURNER FOR PROCESSING OPTICAL FIBER PREFORM

摘要

PROBLEM TO BE SOLVED: To improve a burner not to cause deposition of oxides of the metal burner on a preform by plating at least the top end of the burner with gold. SOLUTION: An optical fiber preform is produced by dehydrating a soot preform in a chlorine gas atmosphere and sintering in an inert gas atmosphere till the preform changes into transparent glass. The preform is processed into a form having a diameter convenient for drawing by using a lathe for glass to stretch while heating with a burner. By plating the burner made of stainless steel or the like with gold, no oxides due to heating are produced on the top end of the burner even when the temp. of the top end of the burner becomes high as 400 to 700 deg.C. Gold plating of the burner is performed by electroplating, vapor deposition or the like so as to coat at least the top end of the burner. The thickness of the gold plating film is properly determined considering the temp. of the top end of the burner and other conditions.