| 摘要 |
PURPOSE:To obtain optical fiber of glass having low loss sent from high-purity preform process, by pulling up a glass rod with the progress of precipitation of raw material to form a preform for a core, forming the preform for clad on the side of it. CONSTITUTION:By using the carbonic acid gas laser 8 for precipitating a core part, the gas nozzle 9 for feeding SiCl4, GeCl4, and O2, the carbonic acid gas laser 10 for precipitating a clad, and the gas nozzle 11 for feeding SiCl4 and O2, first the high silicate glass 12 (consisting essentially of SiO2, containing GeO2) to become the core is precipitated and grown from the tip of a starting rod. After the high silicate glass 12 to become the core is formed to a considerable degree, while the side face of the high silicate glass rod 12 is irradiated with the carbonic acid gas laser, a preform for a clad, namely the quartz glass 13 to become the clad, is precipitated on the surface. When the starting rod is pulled up while being rotated, the preform for optical fiber can be prepared continuously. Finally, it is sent to a drawer, so that optical fiber for long distance can be prepared. |
