| 摘要 |
PURPOSE:To produce the titled preform substituted with OD, easily, economically, at a low cost, by passing D2O vapor in a quartz tube during the step to form a glass thin film on the inner surface of the quartz tube and the step to collapse the tube. CONSTITUTION:The oxyhydrogen burner 3 is reciprocated along the quartz tube 1 supported rotatably with the rotary chuck 2 while heating the outer surface of the quartz tube 1 with the oxyhydrogen flame 4. Keeping the above state, gaseous raw materials consisting of SiCl4 or GeCl4 is introduced at a controlled flow rate through the line 9 into the quartz tube 1 together with the carrier O2 gas, and at the same time, the vapor of D2O is sent through the line 8 into the tube 1 at a controlled flow rate together with the carrier O2 gas. The flow rate of the D2O is controlled by the temperature controller 7 and the flow rate of the carrier O2 gas. An OD-substituted preform of optical fiber can be manufacture easily, without necessitating particular treatment process. |
