SINGLE MODE OPTICAL FIBER WITH ELECTRON VACANCIES

摘要

The invention provides a single mode optical fiber suitable for high speed/large capacity optical communications and optical wiring. A single mode optical fiber comprises a first cladding whose refractive index is uniform, a core whose refractive index is higher than that of the first cladding, and a second cladding consisting of four or more electron vacancies disposed in the region of the first cladding. Optimization can be achieved when the distance from the center of the core to the electron vacancy is 2-4.5 times the core radius and the electron vacancy radius is 0.2 or more times the core radius. Further, it is preferable that the core radius be 3.2-4.8 mum, that the specific refractive index difference of the core with respect to the first cladding be 0.3-0.55%, and that the mode field diameter at a wavelength of 1310 nm be 7.9-10.2 mum. It is also preferable that the specific refractive index difference be 0.12% or less and that the effective core radius from the center of the core to the outermost periphery of the electron vacancy be 23-28 mum.