Optical fiber with a multi-ring core and a large mode area

Abstract

An optical fiber with a multi-ring core and a large mode field, with constant power density across the cross-section of the output optical beam, wherein the refractive profile (core region) consists of multiple cylindrical silica layers, in which layers doped with compounds that increase the refractive index (type A) are separated by layers with a lower refractive index (type B). The layers are arranged in a manner in which the refractive index of the layers doped with compounds that increase the refractive index (type A) increases from the first layer closest to the optical fiber's axis of symmetry to the final layer, forming the core, which is farthest from its axis of symmetry, and the refractive index of the layers with a lower refractive index (type B) is constant or varies with increasing distance from the optical fiber's axis of symmetry.