| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and an apparatus for drawing an optical fiber where the upper space of an optical fiber preform is kept almost uniform, an inert gas is supplied from the upper part of the optical fiber preform, the diameter of the optical fiber is not varied because of a stable gas flow and a preparing work is easily performed. SOLUTION: The optical fiber preform 1 hung and supported by being connected with a dummy rod 2 is placed so as to descend at the inside of a drawing furnace consisting of a heater 5, a furnace core tube 4 and a cylindrical tube 20 connected with the upper end of the furnace core tube and the optical fiber 1a is drawn by heating and melting the optical fiber preform 1. A quartz tube 22 whose outside diameter is between +10 and -20 mm to the outside diameter of the optical fiber preform 1 is arranged so as to stand in a row at the upper part of the optical fiber preform in the outside of the dummy rod 2 and the quartz tube is descended with the dummy rod 2 and the optical fiber preform 1. COPYRIGHT: (C)2011,JPO&INPIT |
