Bend resistant multimode optical fiber

A multimode optical fiber comprising:

• a graded index glass core;
• and
• a glass cladding surrounding and in contact with the core, the cladding comprising a depressed-index annular portion;
• wherein the core has a maximum relative refractive index Δ1MAX, in %, at 850 nm;
• wherein the core and the cladding provide (a) a bandwidth of greater than 750 MHz-km at a wavelength of 850 nm, and (b) a 1 turn 10 mm diameter mandrel wrap attenuation increase at a wavelength of 1550 nm, in dB, of less than or equal to the product of two times (1/Δ1MAX)2.

A multimode optical fiber comprising:

• a graded index glass core extending from a centerline to a radius R1, wherein R1>20 microns;
• and
• a cladding surrounding and in contact with the core, the cladding comprising a depressed-index annular portion and an outer annular portion, wherein the depressed-index annular portion surrounds the core, and the outer annular portion surrounds and is in contact with the depressed-index annular portion;
• wherein the core has a maximum relative refractive index at 850 nm, Δ1MAX, less than or equal to 0.80%;
• wherein the depressed-index annular portion surrounds and is in contact with the core and has a minimum relative refractive index, Δ2MIN;
• and
• wherein Δ1MAX>0>Δ2MIN.

A multimode optical fiber comprising:

• a graded index glass core extending from a centerline to a radius R1;
• and
• a cladding surrounding and in contact with the core, the cladding comprising an inner annular portion, and a depressed-index annular portion;
• wherein:
• the inner annular portion surrounds the core;
• the depressed-index annular portion surrounds the inner annular portion;
• the core has a maximum relative refractive index Δ1MAX at 850 nm;
• the inner annular portion has a maximum relative refractive index Δ2MAX at 850 nm;
• the depressed-index annular portion has a minimum relative refractive index Δ3MIN at 850 nm;
• Δ1MAX>Δ2MAX>Δ3MIN;
• and the inner annular portion has a width W2>0.4 microns.