Abstract
A new optical logic operation technique is proposed that is based on spatial encoding and superposition of a decoding mask with the coded input patterns. Sixteen logical functions of two logical variables can be realized. In the present method, a space-variant logic operation is realized, that is, different logical operations are performed in parallel. The new method is the space-variant extention of the optical shadow-casting logic of Tanida and Ichioka, which is based on a space-invariant logic-gate array. Simple examples are given.