METHOD FOR MANUFACTURING OPTICAL FIBER PREFORM

摘要

PROBLEM TO BE SOLVED: To provide a method capable of manufacturing an optical fiber preform having a uniform shape in a longitudinal direction and small in the fluctuation of relative refractive index difference at the time of forming a soot preform by a VAD method. SOLUTION: The position of a burner 1 for core is moved so that a distance Lx between the center point of the tip part of the burner 1 and a core soot growth point in the X axis direction and a distance Ly therebetween in the Y axis direction are always kept constant by measuring the Lx and the Ly by a 1st image sensor 6 and a 2nd image sensor 7 mounted on the horizontal plane of a core soot growth point.