| 摘要 |
PURPOSE:To deposit a porous optical fiber preform having a prescribed compositional distribution on a starting material, by eliminating fluctuation of flame in the production of a porous optical fiber preform by the deposition of glass soot formed by the flame-hydrolysis of a glass raw material on a starting material in a reaction vessel. CONSTITUTION:The production apparatus of porous optical fiber preform has the following construction. (1) A reaction vessel 11 in which a gas is passed in uniform and straightened state. (2) A means connected to the reaction vessel 11 and generating gas flow in the reaction vessel 11. (3) A rod-shaped starting material 2 reciprocably extending in the reaction vessel 11 along a direction traversing said gas stream and acting as a substrate for the deposition of porous glass. (4) A rotating means to rotate the starting material 2 (holding the starting material 2 with a rotary chuck). (5) A burner 5 placed opposite to the starting material 2 and generating glass soot to be deposited on the starting material 2. The flame of the burner 5 is stabilized e.g. by supplying the vessel 11 with a gas stream of air or nitrogen, etc., filtered with a filter 12 to remove dusts and uniformly straightened in a manner shown by arrows. |
