Optical signal processing using waveguide type acousto-optic switch

It is shown that waveguide type acoustooptic (A-O) switches with wavelength-independent control capability can be applied to optical signal processing and optical computing. Optical switching occurs as a result of collinear interaction between two channel waveguides using guided SAW (surface acoustic waves). The multiplexing number is inversely proportional to the interaction length, and multiplexing of more than 150 wavelengths is possible. Using an integrated A-O switch, matrix multiplication can be performed. As applications of the matrix multiplier, optical implementations of neural networks are discussed. As examples, an implementation of J.J. Hopfield´s (1986) model and an error back-propagation learning model are described