STRESS APPLYING BASE MATERIAL FOR OPTICAL FIBER MAINTAINING POLARIZATION

摘要

PURPOSE:To obtain an optical fiber transmitting linearly polarized light independ ently of external scattering for a long distance by adding GeO2 and SiF4 to SiO2 glass so that the resulting base material has a refractive index which is equal to or lower than that of SiO2 glass. CONSTITUTION:A stress applying part 4 is placed around an SiO2 glass-base core 1 with a buffer layer 2 of SiO2 glass in-between, and an SiO2 glass clad 3 is formed around the layer 4 to obtain an optical fiber maintaining polarization. At this time, a stress applying base material for forming the stress applying part 4 is obtd. by adding GeO2 and SiF4 to SiO2 glass so that the resulting base material has a refractive index which is equal to or lower than SiO2 glass. The viscosity of the part 4 can be made close to that of SiO2 glass, so the deformation of the part 4 during drawing is prevented, and the part 4 can be provided with high symmetry.