OPTICAL MODULATOR AND METHOD FOR DRIVING THE SAME

PROBLEM TO BE SOLVED: To provide an optical modulator with which images are recorded on both the front and the rear surfaces thereof, with only the exposure from either the front or the rear surfaces, while being a comparatively simple structure, and to provide a method for driving the same. SOLUTION: The optical modulator is characterized in that it includes at least a set of optical modulation unit composed of: a pair of display layers 7, 8 each having a lower threshold value which is the operating threshold, with respect to a voltage applied from the outside bringing about a change from a planar phase to a focal conic phase and an upper threshold value, which is an operating threshold, with respect to a voltage applied from the outside bringing about a change from a focal conic phase or a planar phase to a homeotropic phase different from each other, and each constituted of at least a cholesteric liquid crystal; a photoconductive layer 10 interposed and disposed between the pair of display layers 7, 8; and a pair of electrode layers 5, 6 respectively disposed on the surfaces of the pair of display layers 7, 8 opposite to the photoconductive layer 10 side. COPYRIGHT: (C)2007,JPO&INPIT