Patent ID: 8443581

Claim:
A method of producing an optical fiber in which, in a path where an optical fiber is reeled out from a supply bobbin, taken up by take-up means, and wound by a winding bobbin, twists are alternately imparted to the optical fiber by a twist imparting portion, wherein a zone where a high tension load is allowed to be applied to the optical fiber without affecting winding tension of the winding bobbin is disposed, a twist is imparted in the zone, and, when tension immediately before the twist imparting portion is indicated by T (g), a free path length is indicated by L, a twisting amount is indicated by R (turns/m), and a and b are constants, the tension and free path length by which the twisting amount approximated by “R=a×T×L b ” is made “2” or more are set.