| 摘要 |
PURPOSE:To control the thickness of piled soot in good reproducibility by controlling the traverse speed to a source generating glass fine powder, center member, in a specified range, in an outside VAD(Vapor Axis Deposition) method. CONSTITUTION:The soot 2 is attached around a rod 1 to be a core of optical fiber prepd. in advance by a VAD method, etc., by suspending the rod 1 in a chamber 4 for the outside VAD method with a supporting device 6, by hydrolyzing in a flame generated with raw material gas such as SiCl4 and fuel gas such as H2 and O2 through burners 31, 32-3n while rotating and traversing the rod 1 upward. At that time, before starting to pile the soot 2, the traverse speed of the rod 1 to the source generating the soot is determined according to the amt. of the soot 2 to be piled, basing on the correlative curve prepd. in advance of traverse speed-amt. of piled soot and after setting the initial condition, the soot 2 is started to pile up while controlling the speed through a controller 7. |
