METHOD OF PRODUCING OPTICAL-FIBER COUPLER

摘要

The invention provides a method for producing an optical-fiber coupler with a preset branching ratio. The present invention relates to a method in which part of a plurality of optical fibers are made to closely contact with each other so as to form a coupler. The coupler is heated to thereby obtain a predetermined branching ratio; the flow rate of a gas to be supplied to a heat source is increased/decreased by a quantity proportional to a difference between the drawing speed and a preset drawing speed while predetermined tension is applied to the optical fibers.