COOLING APPARATUS FOR OPTICAL FIBER

摘要

PROBLEM TO BE SOLVED: To obtain a cooling apparatus for cooling the space in a cooling cylinder and capable of cooling the cooling cylinder to e.g. <=0 deg.C without causing the moisture condensation in the cylinder in the case of changing the step of an optical fiber. SOLUTION: An optical fiber 3 produced by drawing an optical fiber preform 2 heated in a heating furnace 1 is inserted into a cooling cylinder and a cooling gas is introduced into the cooling cylinder to cool the optical fiber 3 passing through the cylinder. The cooling cylinder of the optical fiber cooling apparatus 10 having the above construction is provided with a cooling means for cooling the cooling cylinder itself and with a heating means to heat the cooling cylinder to room temperature or thereabout.