Theoretical and experimental investigations on an incoherent optical correlator

We demonstrate the function of a nonlinear optical element based on photoan isotropy in ate-dye doped polymers for incoherent image processing. This el ement allows the realization of a matched filter which performs the multipl ication of the Fourier transform of a transparency E-1 with the squared abs olute value of the Fourier transform of a second transparency E-1. Both tra nsparencies are illuminated by a plane wave. The back-transform yields an i ntensity distribution equivalent to convolution of E-1 with the autocorrela tion function of E-2. The main:advantage of this method is the use of two m utually incoherent light beams. A theoretical description and an experiment al verification of this element are presented. (C) 2000 Elsevier Science B. V. All rights reserved.