| 摘要 |
PURPOSE:To prevent the dissipation of a trace component and to easily obtain a base material for a functional optical fiber contg. the trace component in a high concn. by preliminarily forming a porous body by a VAD method and subjecting the same to a dehydration treatment, heat treatment, etc., then adding the high melting point trace component thereto. CONSTITUTION:The porous glass body is produced by the VAD method and is subjected to the dehydration treatment preferably at <=1,400 deg.C in an inert gaseous atmosphere contg. a gas for dehydration (e.g.; gaseous chlorine). After said body is subjected to the heat treatment preferably at <=1,400 deg.C in the inert gaseous atmosphere, the porous body is vitrified to transparent glass in the inert gaseous atmosphere contg. the high boiling point trace component (e.g.; NdCl3), by which the trace component is added to the porous body and the objective base material for the functional quartz optical fiber is obtd. The base material for the functional quartz optical fiber having high performance is thereby easily produced and since the porous body is produced by the VAD method, the large-sized base material is easily produced. |
