| 摘要 |
PURPOSE:To enable the deposition of silica soot on a porous quartz glass preform in high efficiency, by introducing air into a reactor through the secondary air inlet opened at the center of the reactor top and having a specific opening and discharging the reaction gas from plural exhaustion ports opened to the upper and lower parts of the reactor. CONSTITUTION:A seed rod 12 is placed in a reactor furnished with an exhaustion port 14 having an exhaustion apparatus 20. A silicon compound supplied from the tank 4 is subjected to the flame hydrolysis in an oxyhydrogen flame 9 to effect the deposition and growth of silica soot on the seed rod to form a long preform 13 having large diameter. In the above process, air is introduced into the reactor through the secondary air inlet 16 opened at the center of the reactor top and having a specific opening and the reaction gas is discharged from the exhaustion ports 14, 15 opened at the upper and lower parts of the reactor. |
