PROCESS FOR PRODUCING OPTICAL FIBER AND OPTICAL FIBER

摘要

A process for producing an optical fiber in which the optical fiber is twisted when the parent material of optical fiber is drawn by melting such that the range of length where the absolute differentiated value of spin profile becomes 5% or less of the maximum value falls within 10% of the overall length of the optical fiber. The optical fiber is arranged such that the range of length where the absolute differentiated value of spin profile becomes 5% or less of the maximum value falls within 10% of the overall length. The spin profile is preferably triangular. Its period is preferably shorter than the beat length of the optical fiber and the spin amplitude is preferably nπ/2 (n is a natural number).