| 摘要 |
PURPOSE:To manufacture easily a base material capable of giving an optical fiber having a clad layer with a small transmission loss by a vapor axial deposition method in few stages by carrying out the manufacture of a base material for an optical fiber by a specified system using a burner having a quadruply tubed structure. CONSTITUTION:A quartz rod target 20 is suspended in a glass pipe 9 having an exhaust port, and a burner 1 having a quadruply tubed structure is placed so that it faces the target 20. GeCl4, Ar and H2 are fed to the central part of the burner 1, SiCl4, Ar and H2 are fed to the 1st layer at the outside of the central part, and Ar and O2 are fed to the 2nd layer at the outside of the 1st layer and the 3rd layer at the outside of the 2nd layer, respectively. Fine oxide particles produced by hydrolysis are deposited on the tip of the target 20 to grow a porous base material 10. At this time, an inert gas is spouted from glass pipes 6-8 arranged around a flame 25 from the burner 1 so as to provide a prescribed shape to the bottom of the material 10 by control. The state of the bottom during deposition is monitored with a television camera 26 and a display 27. |
