The spatially-distributed recording of the composite filter using the pixelated liquid crystal display

A new recording method using a liquid crystal display (LCD) as an input dev ice to synthesize a composite filter is presented. The filter in the optica l correlator makes use of the multiple diffraction orders from the pixelate d structure of the LCD panel. During the recording stage, each training pat tern is sequentially recorded as a sub-filter at different diffracted order by holographic technology. After that, an input pattern could be simultane ously processed with all sub-filters in parallel such that the composite fi lter can be achieved. This recording method with spatial distribution could avoid the low efficiency of the conventional multi-exposure. The simulatio ns and experimental results show that this system can perform invariant cor relation as a composite filter. (C) 1999 Published by Elsevier Science B.V. All rights reserved.