ANTIRADIATION OPTICAL FIBER, IMAGE FIBER AND PRODUCTION THEREFOR

摘要

PURPOSE:To provide optical fiber of high NA excelling in radiation resistance. CONSTITUTION:A core 1 constituting optical fiber consists of GeO2-F glass free from chlorine and whose Ge-bond defect is compensated by fluorine and a clad 2 consists of SiO2-F glass. Since the core contains no chlorine and the GeO2-bond defect is compensated, the deterioration of radiation property is prevented. Further, since the refractive index of GeO2 is higher than that of quartz glass by 10%, the conventional feature which the difference in specific refractive index between the core and the clad is made large to obtain optical fiber of high NA is not spoiled.