Fibers for Optical Communications

Low‐loss optical fibers based on silica now have a transmission loss value approaching the theoretical limit, and thus attention has turned to other materials. Fibers for optical communications are reviewed in general, and the methods of loss reduction in silica‐based fibers are discussed. Advanced materials and new processing technologies are described for active fibers, in which the light is intentionally modified as it propagates along the fiber, as well as for ultra‐low‐loss passive fibers.