Patent ID: 8054260

Claim:
A driving method of a stacked light modulating device for recording an image therein, the stacked light modulating device comprising a plurality of selective reflection layers each comprising an operationally cholesteric liquid crystal stacked without an electrode intervening between the selective reflection layers, and a pair of electrodes disposed outside stacked layers, the selective reflection layers each reflecting light with different wavelengths within a visible range, and being different in a lower threshold value, which is an operation threshold value of texture change from a planar texture to a focal conic texture with respect to an externally applied voltage, and an upper threshold value, which is an operation threshold value of texture change from the focal conic texture to a homeotropic texture with respect to the externally applied voltage, and the selective reflection layers being different from each other in resistance and capacitance, the driving method comprising: a first step including applying simultaneously, between the pair of electrodes, voltages V 1 and V 2 that each have a first frequency, the voltage V 1 exceeding the upper threshold value of each of a first selective reflection layer and a second selective reflection layer and the voltage V 2 exceeding the upper threshold value of the first selective reflection layer and being less than the upper threshold value of the second selective reflection layer; and a second step including applying simultaneously, between the pair of electrodes, voltages V 3 and V 4 that each have a second frequency, the voltage V 3 being less than the lower threshold value of each of the first selective reflection layer and the second reflection layer and the voltage V 4 exceeding the lower threshold value of the first selective reflection layer and being less than the lower threshold value of the second selective reflection layer, wherein the first frequency is different than the second frequency, the first step sets the texture of the second selective reflection layer when at steady state, and the second step sets the texture of the first selective reflection layer when at steady state, the second frequency is smaller than the first frequency, and the second frequency is in a range of 0 to 100 Hz.