Patent ID: 8103143

Claim:
A single-mode optical fiber, comprising: a central core having an index difference Dn 1 with an outer optical cladding; a first intermediate cladding having an index difference Dn 2 with the outer optical cladding; a first depressed cladding having an index difference Dn 3 with the outer optical cladding that is about −5×10 −3 or less; a second intermediate cladding having an index difference Dn 4 with the outer optical cladding; and a second depressed cladding having a negative index difference Dn 5 with the outer optical cladding; wherein, at a wavelength of 1310 nanometers, the optical fiber has a mode field diameter (MFD) between about 8.6 microns and 9.5 microns; wherein, at a wavelength of 1625 nanometers, the optical fiber has bending losses of about 0.1 dB/10 turns or less for a bending radius of 15 millimeters; and wherein, at a wavelength of 1625 nanometers, the optical fiber has bending losses of about 0.5 dB/turn or less for a bending radius of 7.5 millimeters.