MULTICORE FIBER AND MANUFACTURING METHOD THEREFOR

摘要

A multicore fiber comprising a plurality of unit multicore fibers, wherein the unit multicore fibers comprise a plurality of core parts, and a cladding part that is formed on an outer periphery of the core parts, the cladding part having a refractive index lower than the maximum refractive index in the core parts. The plurality of core parts have approximately the same refractive index profile and mutually different group delays at the same wavelength and the same propagation mode. A core part of the multicore fiber is composed of a cascade connection of the core parts of the plurality of unit multicore fibers. The maximum value of the group delay difference between the core portions of the multicore fiber is smaller than the maximum value of the group delay difference between the core parts of the unit multicore fibers, when converted for the length of the multicore fiber.