Applications of polymeric photorefractive material to reversible data storage and information processing

A polymeric photorefractive composite was prepared from a mixture of carbazole-substituted polysiloxane as a photoconducting medium, 2,4,7-trinitro-9-fluorenone as a photosensitizer, and 2-{3-[(E)-2-(dibutylamino)-1-ethenyl]-5,5-dimethyl-2-cyclohexenyliden} malononitrile as an optically nonlinear chromophore. This polymeric composite, with a thickness of 100 mum, exhibited a high diffraction efficiency of 92% at a low applied electric field of 30 V/mum, which corresponded a refractive index modulation of 3 x 10(-3). Applications of this polymeric composite to reversible holographic data storage and pattern recognition were demonstrated. The three-dimensional image was recorded on our photorefractive film at an applied field of 30 V/mum, and subsequently, a high quality image was reconstructed in a real-time operation. Pattern recognition was successfully demonstrated based on a joint-transform optical correlation. (C) 2003 Wiley Periodicals, Inc.