METHOD FOR MANUFACTURING OPTICAL FIBER PREFORM

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a rare earth-doped optical fiber preform by which the water content in the core part can be removed by an easy method and intrusion of bubbles can be prevented. SOLUTION: A quartz rod 2 doped with Er and Al is inserted into a quartz tube 1 and fixed. SF6gas is made to flow through the space between the quartz tube 1 and the quartz rod 2 to etch the surface of the quartz rod 2 to remove the water content present thereon. Then the quartz tube 1 is externally heated to smoothen the surface of the quartz rod 2. While further the tube is heated, the space is evacuated by a vacuum pump to collapse the quartz tube 1 to weld with the quartz rod 2. COPYRIGHT: (C)2003,JPO