| 摘要 |
PURPOSE:To obtain the porous glass preform having an uniform outer diameter and with the craze and crack reduced by controlling the travel of an oxyhydrogen flame burner while a glass rod makes one revolution to the length almost equal to the diameter of the raw material nozzle. CONSTITUTION:The oxyhydrogen flame burner is opposed to a rotating core glass rod and reciprocated in parallel with the rod, and the glass particles generated by the burner are blown against the periphery of the glass rod to produce a glass particle layer on the glass rod one by one, the process is repeated, and a porous glass preform for the optical fiber is produced by external vapor deposition. In this case, the travel of the burner while the glass rod makes one revolution is controlled to the length almost equal to the diameter of the raw material nozzle of the burner. The spiral deposition of the glass particles is prevented by this method, hence the glass particles are uniformly deposited on the obtained porous glass preform, and the craze and crack of the preform are reduced. |
