| 摘要 |
PURPOSE:Raw materials different in composition are blown out of a pluraity of burners which are directed toward the axis of the supporting rod, onto the surface of the supporting rod covered with a glass-forming raw material, thus producing a basic material for optical-communication glass fiber with a desired refractive index distribution with high reproducibility. CONSTITUTION:A supporting rod of quarts 12 is supported with the supporter 11 in the tightly sealed reacter 17 so that the rod can feely move up and down and rotate. As the rod 12 is rotated about 20rpm, raw materials for glass such as SiCl4, GeCl4 and POCl3 are fed from the lower burner 13 using an oxygen gas as a carrier gas and simultaneously a hydrogen gas is fed from the outside nozzle of the burner 13 to form an oxyhydrogen flame. The raw materials for glass are hydrolyzed to stick around the supporting rod 12 to form a porous glass core rod 14. Then, as the rod is moved up and down and rotated, glass formation materials different in composition are blown out of a pluraity of burners 15 and the operation is repeated to produce the basic material for optical-communication with a desired refractive index distribution with high reproducibility. |
