OPTICAL FIBER PRODUCTION METHOD

摘要

S OF THE DISCLOSURE Disclosed is a method for manufacturing carbon coated optical fiber including the steps of removing adherent foreign material from a surface of a bare optical fiber, and forming at least one carbon layer on the surface thereof using a chemical vapor deposition method. The first step is performed by heating and drying the surface of the bare optical fiber in predetermined temperature region to vaporize the adherent, foreign material while supplying an inert gas to the surface thereof so as to substitute the inert gas for the vaporized adherent foreign material. The second step is performed by thermally decomposing at least one hydrocarbon compound to obtain a thermal decomposate of the hydrocarbon, and depositing the thermal decomposate on the surface of the bare optical fiber. Also, disclosed is a method for manufacturing carbon coated optical fiber including the steps of cooling a surface of a bare optical fiber to a temperature no higher than 50 .degree.C, and forming at least one carbon layer on the surface thereof using a chemical vapor deposition method. The cooling step is performed by supplying a cooled inert gas to the surface of the bare optical fiber.