| 摘要 |
PURPOSE:To expand the transmission band of an optical fiber and to improve its radiation resistance by incorporating the SiO2 free of Cl and having a specified content of F into the fiber. CONSTITUTION:The alkoxysilane such as Si(CH3O)4. and alkoxygermanium such as Ge(CH3O)4 as the glass material are heated in a hydrogen flame to form a soot preform. The particle of SiO2 coated with GeO2 is deposited on the lower surface of the preform and grown to obtain a parabolic soot preform. The preform is dehydrated and sintered in the He and SiF6 atmospheres by an electric furnace, etc., the vitrified preform is drawn in a drawing furnace kept at high temp., and a radiation-resistant optical fiber free of Cl and with the core consisting of GeO2 and SiO2 contg. >=0.1wt.% F and the clad consisting of the SiO3 contg. F is produced. |
