| 摘要 |
An inexpensive low-attenuation optical fiber 1 suitable for use as an optical transmission line in an optical access network is a silica based glass optical fiber and includes a core 11 including the center axis, an optical cladding 12 surrounding the core, and a jacket 13 surrounding the optical cladding. The core contains GeO 2 and has a relative refractive index difference ”core, based on the optical cladding, greater than or equal to 0.35% and less than or equal to 0.50% and has a refractive index volume v greater than or equal to 0.045 µm 2 and less than or equal to 0.095 µm 2 . The jacket has a relative refractive index difference ”J greater than or equal to 0.03% and less than or equal to 0.20%. Glass constituting the core has a fictive temperature higher than or equal to 1400°C and lower than or equal to 1590°C. Residual stress in the core is compressive stress that has an absolute value greater than or equal to 5 MPa. |
