Thomas H. BARNES,¹ Jeffrey A. DAVIS² and Timothy G. HASKELL³

¹Department of Physics, University of Auckland, Private Bag 92019, Auckland, New Zealand, ²Department of Physics, San Diego State University, San Diego, CA 92182, USA, ³Industrial Research Ltd., P.O. Box 31310, Lower Hutt, New Zealand

(Accepted September 6, 1994)

We describe two-input optical logic gates implemented using grating interferometrers. AND, OR, and XOR logic functions are easily implemented with the same optical system, simply by changing the relative spatial phase of the gratings. We also describe an extension of this idea in which a four-grating interferometer is used as an optical half-adder, and demonstrate its operation with experimental results.

Key words : optical logic, optical half-adder, grating interferometer