Optical fiber with enhanced mode coupling

摘要

Optical fibers having enhanced mode coupling produced by an asymmetric refractive index profile that varies periodically along the length of the fiber are described. The prescribed variations are obtained by means of a fabrication process that includes periodically varying the source of at least one of the fiber materials in a direction transverse to the fiber-drawing direction. This transverse periodicity is translated into the desired longitudinal periodicity along the fiber by the fiber-drawing process.