There is a great need of fast temporal-spatial light modulators (TSLMs) for optical processing using coherent beams. Recently we have suggested a fast all-optical spatial-temporal light modulator based on modulation of the reflection band in the dye-doped cholesteric liquid crystal. This fast response (～10{sup}(-9) sec) in the doped cholesteric liquid crystal modulator is due to the fast electronic transitions during absorption of photon by the impurity molecules. This mechanism of temporal light modulation was verified in optical limiters and optical switches in the dye-doped liquid crystals-a five component mixture of cyano- and alcoxy-biphenils with a related chiral additive, with absorbing impurities-ketocyanic dye derivatives. Here we suggest another scheme of fast TSLM based on photoinduced hexagonal array of photorefractive waveguides. It was found, that in some thick photorefractive crystals, counterpropagating laser beams in the presence of a scattering seed develop highly regular hexagonal arrays both in the near and far fields. This phenomenon observed in a 1-cm-thick photorefractive crystal KnbO{sub}3 was explained as the formation of self-induced waveguides, which create the near-field hexagonal pattern by optical channeling. There are two possible modes of operation for TSLM: static and dynamic. In the static mode (most likely in LiNbO{sub}3) long enough exposure, or temperature annealing should fix the hexagonal pattern, created by counterpropagating beams along the c-axis. After fixing, we expect an array of photoinduced waveguides, each of them containing reflection-type gratings. We may consider this structure as an array of optical fibers with imprinted reflection gratings. It is known that fiber-gratings have been successfully tested as new very effective sensors of any tiny changes of the refractive index. In our case, the hexagonal array of light induced waveguides may be considered as an array of "pixels" with imprinted refractive-index gratings as the sensitive elements which would convert an incoming incoherent image into spatial modulation of the near-field channeling pattern.
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