Mode Coupling Effects in Plastic Optical Fibers

Abstract

In optical fibers for data transmission applications, a most important characteristic along with total attenuation is the optical bandwidth that defines the limit of information carrying capacity.1 Besides compensation for modal dispersion through a parabola-like graded index profile, mode coupling is a mechanism important to increased fiber bandwidth performance. Mode coupling changes the length dependence of the bandwidth, or equivalently, the inverse pulse broadening, from linear to square root behavior, usually through extrinsic features which might include micro bends, diameter variations, micro voids, cracks etc. In this paper, we report the observations of mode coupling effects in plastic optical fibers (POFs) using time-domain bandwidth measurements of high quality step index (SI) POF.2-4 Our results are directly verified by independent measurements of the far-field radiation patterns.