Image rendering of spatial light modulators (SLMs) is often degraded by various effects. Some efficient methods to get around nonuniformity, nonlinearity, and remanence and improve image rendering are presented. Optical laboratory results are presented for an analog ferroelectric liquid-crystal SLM using a high-speed camera. Focus is made on a preprocessing compensation method, using a spatial-dependant correction table. A high-speed "on-the-fly" implementation is also suggested.
One coherent processor and one incoherent processor, both including an active contour optical implementation were constructed and are presented. The coherent processor consists of a complete optical target tracking processor combining a Joint Transform Correlator with an optical implementation of a segmentation method based on active contours or "snakes". The incoherent processor is an optoelectronic multichannel processor that is able to segment an object in a real image. The process is based on an active contour algorithm that has been transposed to optics in order to accelerate image processing. The correlator, in its multichannel version, speeds up the overall frame rate of the optoelectronic processor. Experimental results for both processors are presented.
We present the implementation of dynamic Diffractive Optical Elements on three different types of commercially available liquid crystal spatial light modulators, each of them featuring a different modulation capability. The one using Twisted-Nematic liquid crystal exhibits coupled amplitude and phase modulation, the one using analog Ferroelectric liquid crystal a pure amplitude modulation and the one using Nematic liquid crystal a pure phase modulation. Based on experimental results, the performance of these three devices is compared.
This paper presents an incoherent optoelectronic processor which is able to segment an object in a real image. The process, based on active contours (snakes), consists in correlating adaptive binary references with the scene image or with a preprocessed version of the scene image. The proposed optical implementation of algorithms which are already operational numerically opens attractive perspectives as far as speed is concerned. Furthermore, this experiment is a new application for optical processors.