| 摘要 |
PURPOSE:To easily form a glass deposited layer having a desired composition by introducing gaseous starting material with a high b.p. into a reaction tube from a feeding pipe through a movable type heat insulating feeding pipe internally provided with a heating means. CONSTITUTION:The gaseous starting material introducing end 21 of a reaction tube 1 with both ends attached to a rotating mechanism 2 is connected to one end of a gaseous starting material feeding pipe 22 through connecting members 23, 24 and a movable sealing part 25, and a movable type gaseous starting material feeding pipe 27 provided with a heating means 33 between the inner pipe 31 and the outer pipe 32 is placed through the member 23 at the end 21. The inner pipe 31 of the feeding pipe 27 is heated, and gaseous starting material with a high b.p. is introduced into the tube 1 from the pipe 22 through the pipe 27. At the same time, while moving a heating means 3 in the longitudinal direction of the tube 1, the tube 1 is heated to a high temp. to melt the reaction product deposited on the inner wall of the tube 1. Thus, a transparent glass layer is formed. |
