Patent ID: 8340488

Claim:
A multimode optical fiber, comprising: a glass-based, graded-index central core having a radius r 1 of less than about 40 microns and an alpha refractive index profile, said central core having a maximum refractive index n max and, at said central core's radius r 1 , a minimum refractive index n min ; and a glass-based, core-contiguous cladding immediately surrounding said central core, said core-contiguous cladding having a radius r 2 and a maximum refractive index n cladding ; wherein, at said central core's radius r 1 , the central core's minimum refractive index n min is at least 2×10 −3 greater than the core-contiguous cladding's maximum refractive index n cladding ; and wherein, for two turns around a radius of curvature of 15 millimeters at a wavelength of 850 nanometers, the optical fiber exhibits a bending loss of less than 0.1 dB.