Structural changes caused by the optically induced helical inversion in the cholesteric liquid crystal cells with homeotropic anchoring are studied. In a one-step exposure, a sequence of structural transformations "lying left-handed helix - unwound homeotropic state - lying right-handed helix" is realized. In this process, smooth expansion of a left-handed helix, transition to an unwound state, emergence and smooth compression of a right-handed helix was observed. The unwound state was maintained over a rather wide range of exposures. Well-oriented and highly periodic fingerprint textures capable of the above mentioned structural changes were obtained by rubbing the aligning substrates. This allowed for obtaining photo-tunable diffraction gratings and using them to demonstrate new beam steering principle. Also, pitch reversal suggested new options for optical recording, in particular contrast reversal and edge enhancement.

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Microwrinkles generated by thin film buckling on elastic substrates serve as reconfigurable microgrooves that can align nematic liquid crystals (NLCs). Through rapid switching of the groove direction to generate controlled perturbation in surface-induced NLC alignment, we studied the dynamical behavior of the surface memory effect. Combined with annealing that resets the alignment memory, the time-dependent response to groove switching indicates that substantial memory develops in a few seconds after contact between the surface and the nematic phase.

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Liquid crystal polarizers are prepared by using a common linear polarizer, a nematic liquid crystal and PVA-coated glass substrates. The surface of one substrate is treated for unidirectional molecular orientation and the other substrate is treated for concentrically circular molecular orientation. The liquid crystal cell has axially symmetrical polarization properties, that is, a concentrically circular or radial polarization can be achieved.