Patent ID: 6904218

Claim:
An optical fiber communications system, comprising: at least one source of optical energy; an optical fiber cable comprising an optical fiber having a positive dispersion and a positive dispersion slope, the optical fiber cable being coupled to said at least one source of energy, the optical fiber having a core region and a cladding region surrounding the core region, the fiber having an effective area, A eff , that is equal to or greater than approximately 80 micrometers squared (μm 2 ) at a wavelength of approximately 1310 nm and having a cable cutoff wavelength less than or equal to approximately 1310 nm, wherein the core region is segmented into at least first and second refractive index portions, the first and second refractive index portions having first and second relative indexes of refraction n 1a and n 1b , respectively, that are different from each other, and wherein the first and second relative indexes of refraction are positive.