2026-04-17T02:43:38Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1707192025-11-19T11:00:01Zcom_2072_1057col_2072_478821col_2072_478917

Pattern detection using a modified composite filter with nonlinear joint transform correlator Vallmitjana i Rico, Santiago Juvells Prades, Ignacio Carnicer González, Arturo Campos Coloma, Juan Reconeixement òptic de formes Òptica de Fourier Optical pattern recognition Fourier optics A simple method for optical implementation of a composite filter in a joint transform correlator is presented. A composite filter in object space is a real function, but by adding an appropriate constant value, only positive values are obtained. As a drawback, the bias introduced decreases the relative height of the correlation peaks in the recognition process. Non-linear effects in a joint transform correlator are used to increase discrimination by using positive composite filters. Digital simulation and optical implementation of the process has been carried out, achieving the non-linearities by means of saturation effects on the intensity detection process. 2020-09-22T11:30:56Z 2020-09-22T11:30:56Z 1991 2020-09-22T11:30:56Z info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Reproducció del document publicat a: https://doi.org/10.1117/12.49717 Proceedings of SPIE, 1991, vol. 1564, p. 266-274 https://doi.org/10.1117/12.49717 (c) Society of Photo-Optical Instrumentation Engineers (SPIE), 1991 info:eu-repo/semantics/openAccess Society of Photo-Optical Instrumentation Engineers (SPIE) Articles publicats en revistes (Física Aplicada)