Optical Switches

Abstract Extensive research has been focused on constructing the next‐generation all‐optical broadband IP networks. The design goal is to avoid having any optical‐electrical‐optical conversions in a signal path. Therefore, the optical switches are to be the core part of all‐optical networks. An optical switch may cover optical cross connects and optical add‐drop multiplexers. In this article, we focus on the design of large‐scale optical cross connects (OXCs). There are passive and active OXCs. The path settings in networks are pre‐configured if passive OXCs, made with arrayed waveguide gratings (AWGs), are used. Active OXCs enable networks to set up paths dynamically. There are several new and promising technologies developed for the active OXCs. This article is focused on micro‐electromechanical systems (MEMS), liquid crystals and thermo‐bubble‐based switches. Their future deployments will definitely have a considerable impact on all‐optical IP networks.