Aspect insensitive incoherent optical pattern recognition Available to Purchase

An incoherent optical Correlation scheme is presented in which electronically edge-enhanced images are introduced using a high-brightness, narrow bandwidth CRT. Aspect insensitivity is achieved through use of a novel multiplexing technique. Several angular views of the object to be recognized are edge-enhanced and binary. Images arising from adjacent views are logically ANDed to remove highly angularly sensitive information. Resulting images are then logically ORed with others so that information from several angular ranges is included in this new image, which in turn is used for the construction of a holographic filter. This filter is designed for use in an incoherent correlator. This system offers advantages of compactness and alignment insensitivity compared to coherent filtering, as well as the fact that a spatial light modulator is not required. Similar incoherent experiments from a mailing label recognition project are discussed.