METHOD OF AND DEVICE FOR PRODUCING GLASS PREFORM

摘要

PROBLEM TO BE SOLVED: To provide a glass preform capable of manufacturing a high efficiency and highly reliable optical fiber in which contamination in an interface between a core rod and a glass tube is prevented and the intrusion of an OH group is eliminated. SOLUTION: This production method for the glass preform is characterized by including a process for mounting a dummy pipe provided with a gas supply port (43) and its discharge port (44) at one end of a glass tube 31 into which a core rod 32 is inserted, and a process for gradually heating the glass tube from the other end thereof while letting a gas flow from the port (43) toward the port (44) to weld the core rod 32 and the glass tube 31. COPYRIGHT: (C)2003,JPO