DRIVING METHOD OF STACKED TYPE OPTICAL MODULATOR, AND DRIVING APPARATUS OF STACKED TYPE OPTICAL MODULATOR

摘要

PPROBLEM TO BE SOLVED: To provide a driving method and a driving apparatus of a stacked type optical modulator enlarging an operation margin and achieving stable threshold shift driving while incorporating sufficient reflectance into each display layer. PSOLUTION: In the stacked type optical modulator, a plurality of selective reflection layers 7a and 7b comprising cholesteric liquid crystals which selectively reflect visual beams having mutually different wavelengths and have both upper and lower operation thresholds to external application voltage different from each other are stacked and electrodes 5 and 6 are disposed on the outer side thereof. For recording an image in the stacked type optical modulator, the driving method and the apparatus include (1) a first writing step for applying voltages having the same frequency and at least two or more heights and including a voltage V1 between the electrodes 5 and 6 to perform selective driving of the upper thresholds in the respective selective reflection layers 7a and 7b and (2) a second writing step for applying voltages having the same frequency different from that of the voltage V1 and at least two or more heights and including a voltage V2 between the electrodes 5 and 6 to perform selective driving of the lower thresholds in the respective selective reflection layers 7a and 7b. PCOPYRIGHT: (C)2007,JPO&INPIT