Patent ID: 8428410

Claim:
A multimode optical fiber, comprising: a central core having (i) a radius r 1 , (ii) an alpha-index profile, and (iii) at said radius r 1 , a negative refractive index difference Δn end with respect to an outer cladding of greater than about −1×10 −3 ; an inner cladding positioned between said central core and said outer cladding, said inner cladding having (i) a radius r 2 , (ii) a width w 2 , and (iii) a refractive index difference Δn 2 with respect to said outer cladding; and a depressed trench positioned between said inner cladding and said outer cladding, said depressed trench having (i) a radius r out , (ii) a width w 3 , (iii) a refractive index difference Δn 3 with respect to said outer cladding of between about −15×10 −3 and −3×10 −3 , and (iv) a volume v 3 .