| 摘要 |
<p>A method of stretching an optical fiber base material comprising the step of gripping the opposite ends in a length-wise direction of an optical fiber base material with a pair of grip tools and moving one or both of the pair of grip tools in a first direction parallel to the above length-wise direction to thereby pull the optical fiber base material while moving a heating device relatively to the optical fiber base material in a second direction opposite to the first direction; and a device therefore; wherein the above optical fiber base material is stretched while the above relative moving speed Vb(x) is changed according to the expression (1): Vb.[Dmax/D(x)] 2 <= Vb(x) <= Vb.[Dmax/D(x)]3 (1), in the expression, Vb denotes a reference speed, Dmax the maximum outer diameter of the optical fiber base material, D(x) the outer diameter of the optical fiber base material at a heated position x, and Vb(x) the moving speed of a heating device relative to the optical fiber base material when the optical fiber base material is at a heated position x.</p> |
