Optical computing based on a selector logic

Optical logic operations based on a selector logic are proposed. Based on the parallelism of optics, the selector logic is realized by data beam selections through a polarization switching device and a birefringent plate. The optical selector unit proposed here is composed of a pair of 90° twisted nematic liquid crystal cells, a birefringent crystal plate, and a mask. Several logic gates (AND, OR, XOR, and XNOR gates) and a full adder are demonstrated based on the proposed optical selector logic. The parallelism of optics makes it easy to implement the selector logic. As a result, optical parallel logic operations are performed by cascading the selector units and the interconnection problems for a large scale logic circuits can be avoided.