OPTICAL-INTENSITY FILTERS FOR PATTERN-RECOGNITION

All the shape information of an object is preserved in its quarter-spe ctrum (QS). Some new uses of optical filters for pattern recognition b ased on QS are introduced. These filters are intensity functions sc th at amplitude modulating spatial light modulators or photographic film can be used. Some of the new filters yield better correlation performa nces than the phase-only filter and the amplitude-encoded phase-only f ilter. Computer simulations and optical experiments show the results.