Optical logic with variable-grating-mode liquid-crystal devices

A liquid-crystal device that performs a two-dimensional intensity-to-spatial-frequency conversion has been investigated for use as an optical transducer. When such a device is used as the input transducer in an optical filtering arrangement, image-intensity levels can be easily manipulated by using appropriate Fourier plane filters. The variable-grating-mode liquid-crystal device is well adapted to performing binary logic operations on images. Results demonstrating the implementation of common logic operations are presented.