Incoherent optical correlators

The use of optical systems in signal processing applications can offer significant advantages over an equivalent electronic approach. These advantages stem chiefly from the high-speed analog multiply and parallel processing capability inherent in an optical system. This can be used to advantage in application areas requiring large quantities of data to be processed in near real time. Presented in this paper is a review of a variety of incoherent optical analog techniques for performing correlation and linear transform operations. Both scanning and nonscanning systems using spatial and/or temporal inputs are considered.