PURPOSE: To provide the method for drawing an optical fiber for production of the high-quality optical fiber having a uniform shape.
CONSTITUTION: The image of the foremost end 62a of a perform 62 for the optical fiber melted to a meniscus form by heating in a heating furnace 68 is picked up by a CCD camera 2 and its area is calculated by an image processing section 4, by which the volume of the molten foremost end 62a is estimated. Whether the calculated area is a prescribed value or not is compared in an image recording and comparing section 6 which outputs a differential signal S6 to a speed controller 5. This speed controller 5 controls a motor 74 at the feed speed R based on the differential signal S6 and regulates the transporting speed of the preform 62 for the optical fiber to be introduced into the heating furnace 68.
INABA SHIGEO
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