Nematic liquid crystals as media for real-time holography

We report on a novel type of orientational photorefractive devices consisti ng of dye-doped or pure nematic liquid crystals. These systems can be emplo yed as the recording media for real-time (dynamic) holography. Optical addr essing of liquid crystal molecules is facilitated due to the natural tenden cy of molecular self-assembling in nematics and their easy reorientation up on action of an electric field. This field can be produced by incoming ligh t via photoconductivity either in the bulk or at the surface of the nematic liquid crystal layer. We present an experimental study of dynamic self-dif fraction of light on thin phase holograms formed in a nematic liquid crysta l panel. Optically addressed spatial light modulators designed by us can be the active elements of image processing systems and in this communication we demonstrate the optical correlator performing image recognition.