BANDWIDTH-MAINTAINING MULTIMODE OPTICAL FIBER

PROBLEM TO BE SOLVED: To provide an optical fiber having specified design parameters, i.e., controlled refractive index design ratios and dimensions which render the optical fibers largely immune to moderate severe bends. SOLUTION: The multimode optical fiber comprises: a core region having a first radius a1and a profile alpha; an inner cladding extending radially from a1to a second radius a2; a trench extending radially from the second radius a2to a third radius a3; and an outer cladding extending to a fourth radius a4, wherein the maximum refractive index d1of the core region, a refractive index d2of the inner cladding, a refractive index d3of the trench and a refractive index d4of the outer cladding have specified values. Accordingly, the modal structure in the optical fiber can remain essentially unimpaired without being substantially unaffected by bending. COPYRIGHT: (C)2010,JPO&INPIT