OPTICAL FIBER WITH LARGE MODE FIELD DIAMETER AND LOW MICROBENDING LOSSES

摘要

Optical fibers having a mode field diameter at 1310 nm of at least 8.8 μm, wire mesh covered drum microbending losses at 1550 nm less than 0.03 dB/km, and a 2 m cutoff wavelength less than 1320 nm. The fibers may include a central core region, an inner cladding region, an outer cladding region, a primary coating with an in situ modulus less than 0.20 MPa and glass transition temperature less than −35° C., and a secondary coating with an in situ modulus greater than 1500 MPa. The fibers may further include a depressed index cladding region. The relative refractive index of the central core region may be greater than the relative refractive index of the outer cladding region may be greater than the relative refractive index of the inner cladding region. The fibers may be produced at draw speeds of 30 m/s or greater.

主权项

1. An optical waveguide fiber comprising:
a central core region having a radius r1 and a relative refractive index Δ1(r) in % measured relative to pure silica, said relative refractive index Δ1(r) having a maximum Δ1max; a cladding, said cladding including an inner cladding region surrounding said central core region and an outer cladding region surrounding said inner cladding region, said inner cladding region having an outer radius r2>8 μm and a relative refractive index Δ2(r) in % measured relative to pure silica, said relative refractive index Δ2(r) having a maximum Δ2max and a minimum Δ2min, said outer cladding region having a relative refractive index Δ4 in % measured relative to pure silica, said relative refractive index Δ4 being positive and less than said maximum Δ1max, said relative refractive index Δ4 exceeding said minimum Δ2min by at least 0.002%; a primary coating surrounding said outer cladding region, said primary coating having an in situ modulus of less than 0.20 MPa and an in situ glass transition temperature of less than −35° C.; and a secondary coating surrounding said primary coating, said secondary coating having an in situ modulus of greater than 1500 MPa.