| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an apparatus for producing a porous quartz glass preform in which leak of a gas such as hydrogen chloride from a reaction furnace synthesizing a porous quartz glass is prevented, and also, the intrusion of a foreign matter from the outside of the reaction furnace can be prevented, and to provide a method for producing the porous quartz glass preform. <P>SOLUTION: A supply and exhaust device 10 includes: a pipe line 11 for gas feed for feeding clean gas to the inside of the supply and exhaust device 10; and a pipe line 9 for gas exhaust for exhausting the gas leaked out to the inside of the supply and exhaust device 10 from the reaction furnace 101. Here, an ascending air current is discharged from a gap 17 formed between an opening part 7 disposed at the upper face of the supply and exhaust device 10 and a seed rod 108 pierced through the opening part 7, to the outside. <P>COPYRIGHT: (C)2012,JPO&INPIT |
