| 摘要 |
PURPOSE:To inhibit the damage and deterioration of a core tube made of carbon and to obtain glass for an optical fiber having a stabilized transmission loss by heating a quartz glass body in the core tube in an atmosphere of a gas having C-F bond. CONSTITUTION:A semi-sintered body, aggregate or porous body of fine SiO2 glass particles formed by VAD or other method is held in a core tube made of high purity carbon in a heat treating furnace and glass for an optical fiber is obtd. by heating in an atmosphere of a gas having C-F bond, preferably CF4, CCl2F2 or C2F6. |
