Optical switch

In telecommunication, an optical switch is a switch that enables signals in optical fibers or integrated optical circuits (IOCs) to be selectively switched from one circuit to another. The word is used on several levels. In commercial terms (such as "the telecom optical switch market size") it refers to any piece of circuit switching equipment between fibers. The majority of installed systems in this category actually use electronic switching between fiber transponders. Systems that perform this function by physically switching light are often referred to as "photonic" switches, independent of how the light itself is switched. Away from the world of telecom systems, an optical switch is the unit that actually switches light between fibers, and a photonic switch is one that does this by exploiting nonlinear material properties to steer light.
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A switch that enables signals in optical fibers or integrated optical circuits (IOCs) to be selectively switched from one circuit to another. Note 1: An optical switch may operate by (a) mechanical means such as physically shifting an optical fiber to drive one or more alternative fibers, or (b) electro-optic effects, magneto-optic effects, or other methods. Note 2: Slow optical switches, such as those using moving fibers, may be used for alternate routing of an optical transmission path, e.g., routing around a fault. Fast optical switches, such as those using electro-optic or magneto-optic effects, may be used to perform logic operations.