Patent ID: 7171090

Claim:
An optical waveguide fiber comprising comprising: a core with a refractive index profile having, a radius, an alpha and a relative refractive index characterized by delta % that varies along said radius; at least one cladding surrounding said core; wherein said alpha is less than 2.5, peak refractive index delta % in said core is between 0.34% and 0.4%, said relative refractive index is less than 0.01% for all radii greater than 7 μm, and said optical waveguide fiber having a mode field diameter MFD at a wavelength of 1310 nm of no more than 9.54 μm, and attenuation less than: (a) 0.329 dB/km at a wavelength of 1310 nm, (b) 0.290 dB/km at a wavelength of 1383 nm, (c) 0.255 dB/km at a wavelength of 1410 nm, and (d) 0.189 dB/km at a wavelength of 1550 nm.