Patent ID: 7903918

Claim:
A bend resistant optical fiber which is multi-moded at 1300 nm comprising a core, an inner cladding, a low index ring and an outer cladding, wherein: the core is formed from silica-based glass and comprises a graded index of refraction with a core alpha profile where 1.9≦α C ≦2.1, a maximum relative refractive index percent Δ 1Max % relative to the outer cladding, and a numerical aperture NA of greater than 0.23; the inner cladding surrounds and is in direct contact with the core, the inner cladding having a maximum relative refractive index percent Δ 2Max % relative to the outer cladding, a minimum relative refractive index percent Δ 2Min % relative to the outer cladding, and a radial thickness of at least 0.5 microns, wherein Δ 1Max % is greater than Δ 2Max %; the low index ring that surrounds and is in direct contact with the inner cladding such that the low index ring is spaced apart from the core, the low index ring having a relative refractive index percent Δ 3 % relative to the outer cladding, a radial thickness of at least 0.5 microns and a profile volume with an absolute magnitude of greater than 50%-μm 2 , wherein the minimum relative refractive index percent Δ 2Min % of the inner cladding is greater than or equal to Δ 3 %; and the outer cladding surrounds and is in direct contact with the low index ring, the outer cladding comprising a relative refractive index percent Δ 4 % relative to pure silica glass, wherein Δ 1Max %>Δ 4 %≧Δ 2Max %.