PRODUCTION DEVICE AND METHOD FOR OPTICAL FIBER

摘要

A fiber drawing device (1) has a fiber drawing furnace (11), a heating furnace (21) and a resin curing unit (31). An He gas supply passage (15) from a supply unit (14) is connected to a furnace tube (13) of the fiber drawing furnace (11), for supplying an He gas. An optical fiber (3) heat-drawn in the fiber drawing furnace (11) is fed to a heating furnace (21), and a preset portion of the optical fiber (3) is gradually cooled at a preset cooling speed. An N2 gas supply passage (25) from an N2 gas supply unit (24) is connected to a furnace tube (23) of the heating furnace (21), for supplying an N2 gas. Later, a UV resin (39) is applied to the optical fiber (3) by a coating die (38) and then is cured at the resin curing unit (31) to produce an optical fiber strand (4).