Process of drawing optical fiber.

摘要

There is provided a process of melt drawing an optical fiber (119) from a preform (101) therefor in which a heating furnace (1) comprising a muffle tube (2) inside thereof through which the optical fiber (119) is passed is provided immediately below a melt drawing furnace (105) to further draw the optical fiber (119) while heated, and an interior of the muffle tube (2) is kept in an atmosphere selected from the group consisting of an inert atmosphere, an atmosphere comprising oxygen gas and an atmosphere comprising hydrogen gas.