An optical fiber for use in optical energy transmission system has improved
mode coupling in one embodiment thereof and both improved mode coupling
and selective attenuation of unwanted modes in another embodiment. The
optical fiber includes a plurality of particles of refractive index
differing from that of the fiber core, in which the particles are
distributed, and from that of the fiber cladding in which, in one
embodiment, particles are distributed.
In fabricating the fiber, the particles are introduced into the preform
from which the fiber is drawn, and, in a co-extrusion process, they are
also introduced into the polymer prior to its being extruded with the core
material.
