PRODUCTION OF HIGH-PURITY GLASS BODY

摘要

PURPOSE:To obtain easily the titled high-purity glass body having high dimensional accuracy and a deposit having specified thickness by forming a specified glass fine-particle deposit while keeping the ratio of the weight of the deposit to the parallel travel at a specified value and lifting the deposit. CONSTITUTION:A seed rod 7 is fixed to a load cell 5 through a chuck 6 and made rotatable and vertically movable. A raw gas such as SiCl4 is mixed into an oxyhydrogen burner 4 and introduced over the outer periphery of a starting base material 2 at the lower end of the seed rod 7 to deposit the formed fine- particle glass body 1 in a semisintered state to form a glass fine-particle deposit 3. At the same time, the weight omega of the seed rod 7 plus the deposit or the change rate in weight omega dot is measured through a chuck base 8 and an output converter 11 of the dots omega and omega. Meanwhile, a parallel travel (l) between the base material 2 and the burner 4 or the parallel traveling velocity dot is detected by a detector 9 and the (l) dot is controlled by a controller 10 so that the omega/l or omega dot/l dot is made constant at all times and simultaneously the rod is lifted to form the deposit 3 which is sintered at bout 1,650 deg.C and vitrified.