Abstract

High bandwidth in graded-index multimode fibers can only be realized with well-defined refractive- index profiles. Calculations predict that deviations of the order of a few percent, which are typical in manufacturing processes, lead to a drastic reduction in bandwidth of an order of magnitude or more. However, fluctuations in the distortions over the fiber length partially reduce the effects of the profile defects.^1-3 As a result of the inherent properties of the PCVD process, experimentally well-defined profile defects can be reliably prepared. Thus the quality of the lightguiding structure and the application of model calculations to real fibers can be experimentally verified.

© 1983 Optical Society of America