Optical flip-flops and sequential logic circuits using a liquid crystal light valve.

This paper is concerned with the application of optics to digital computing. A Hughes liquid crystal light valve is used as an active optical element where a weak light beam can control a strong light beam with either a positive or negative gain characteristic. With this device as the central element we have demonstrated the ability to produce bistable states from which different types of flip-flop can be implemented. In this paper we first present some general comments on digital computing as applied to optics. This is followed by a discussion of optical implementation of various types of flip-flop. These flip-flops are then used in the design of optical equivalents to a few simple sequential circuits such as shift registers and accumulators. As a typical sequential machine, a schematic layout for an optical binary temporal integrator is presented. Finally, a suggested experimental configuration for a optical master—slave flip-flop array is given.

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