RESIN STRENGTH EVALUATION METHOD, OPTICAL FIBER MANUFACTURING METHOD, AND OPTICAL FIBER

摘要

PROBLEM TO BE SOLVED: To discriminate the presence or absence of a void V or cracks at a stress working region R2a while tensile stress (σr,σθ,σz) is being applied in a nearly uniform three-dimensional direction to the stress working region 2a. SOLUTION: In the evaluation method of the resin strength, a resin film R2 is cured so that the resin temperature of the resin film R2 becomes the resin temperature of a primary coating layer 9 in assumed covering layer curing. Then, the resin film R2 is placed under an observation environment of the same observation environmental temperature as an optical fiber usage environmental temperature being assumed along with a first restriction plate 3 and a second restriction plate 5. COPYRIGHT: (C)2004,JPO