A proposed electro-optical implementation of lateral inhibition with phase-only filters

This article describes a proposed electro-optical implementation of the lateral inhibition function and its simulation. Lateral inhibition is the most important adaptation property in sensory systems and with this mechanism, weak inputs to neurons are suppressed (inhibited) by strong inputs to neighboring neurons. The purpose of lateral inhibition is to enhance and emphasize boundaries. Two types of lateral inhibition filters were studied, both symmetric and antisymmetric. The antisymmetric are direction dependent and thus, four different directions were chosen. Since the electro-optic implementation relies on filtering input images in the Fourier plane, the inhibition filters used in the simulation are phase-only. The simulation takes into consideration performance of specific optical hardware components and was tested on signals that have very sharp directional edges in addition to a facial image with many contour line edges. © 1997 John Wiley & Sons, Inc. Microwave Opt Technol Lett 15: 98–102, 1997.