Abstract

Our novel nonlinear detection system is based on a pseudocorrelator. The basic operation of the system is as follows. A transparency containing a multitude of objects to be detected/discriminated against is placed at the input plane. After a plane wave is superimposed on the Fourier transform, the interference pattern is recorded by a television camera. Then, after some nonlinear operations on the above-mentioned pattern are performed, an appropriately real coded, phase-only filter is displayed on an spatial light modulator (SLM). Illumination by a plane wave of the SLM and multiplication by a spatial filter leads, after a Fourier transform, to the required correlation plane. Simulations and theoretical investigations of the above method indeed show promising results in terms of both detection and discrimination capability. We believe that we have an approach to pattern recognition that yields superior results. This system should provide an attractive detection system.

© 1990 Optical Society of America