Optical Switches

Abstract

Optical switches are used in optical communications networks to switch signals optically, rather than electronically. As the signal is not converted to the electronic domain, optical switches can consume less power than electrical switches. Optical switches are also proposed as photonic packet switches and as a replacement core for electrical switches. Free-space optical switches are commercially deployed today in key applications such as wavelength selective switches in DWDM networks, and reconfigurable patch panels. Optical switches based on planar lightwave circuits in silicon-on-insulator technology are drawing attention of the research community due to their small size and fast switching time. As a result, practical optical packet switches are in development for the near future. This article summarizes optical switching technologies, their characteristics and key applications for metro networks and data centers, with granularity ranging from wavelength circuits, to flows, to packets.