US 8,014,645 B2 · Dispersion shifted optical fiber

Abstract

A 1.55 μm band dispersion shifted optical fiber is provided which has a low loss and low dispersion slope. A core region “a” is heavily doped with GeO2 . A core region “b” is composed of pure SiO2 glass. A cladding section is arranged around the core region. The cladding section has a lot of holes extending in the longitudinal direction of the optical fiber. The holes of the cladding section are not located at random, but have a honeycomb structure composed of regular hexagons which have a side length of Λ, and serve as a primitive lattice. The center of the core section has a region having a refractive index higher than that of the periphery of the core section. The core section has the refractive index distribution in which the group velocity dispersion at the operation wavelength of the region becomes the normal dispersion.

Claims9

Dependent claims

A dispersion shifted optical fiber comprising:

a cladding section including a plurality of holes extending in a longitudinal direction and arrayed geometrically;
and
a core section having at its center a region whose refractive index is higher than a refractive index in a periphery of said core section, said core section being configured to have a propagation mode and a normal dispersion at an operation wavelength of 1.55 μm if no holes were present in the cladding section, and said cladding section being configured with the plurality of holes to compensate the normal dispersion of the core section at the operation wavelength and further configured with a positive dispersion slope at the operation wavelength to increase confinement effect and decrease loss at higher operation wavelengths.

Dependencies are inferred from the claim text.

Dispersion shifted optical fiber

Life of this patent

Dispersion shifted optical fiber

Life of this patent

Abstract

Claims9