Abstract

Adaptive resonance is a theory of unsupervised learning in neural networks.¹ We propose an invention that allows parallel execution of the most computationally intensive parts of the architecture by using optical hardware. The rest of the design is carried out in electronics. The basic configuration of the electro-optical ART unit is a two-lens optical correlator. A spatial light modulatoris configured as a binary phase-only filter and contains the two-dimensional Fourier transform of the input pattern. The plane of this device is between the two lenses. The template plane is to the left of the first lens. It contains multiple templates simultaneously. The lenses are chosen such that the paraxial approximation applies, and the template Fourier transforms will overlap. On the output plane, we have a charge-coupled device (CCD) camera. This plane will have correlation peaks corresponding to templates that closely match the input image. All electronic calculations and control of the spatial light modulators are done by a microVAX. This is also used to process the CCD camera output via a frame grabber.

© 1990 Optical Society of America