Size-speed trade-off in optical switching elements

The basic building blocks of an interconnection network are the switching elements. We examine two optical implementations for a basic switching element: (1) ferroelectric liquid-crystal light valves and (2) Fabry-Perot étalons. For these two examples we report a trade-off between the size, i.e., the number of input and output channels, and the switching speed. We speculate that it may be a general property of optical switching elements that size and speed cannot be optimized simultaneously.