| 摘要 |
PROBLEM TO BE SOLVED: To obtain a display device in which the efficiency of time use can be increased and a bright display with high contrast can be obtained for the display screen of animated images, and for the display of static images, the content of the display can be held with no or a little power supply without repeatedly writing or continuously applying a bias voltage. SOLUTION: The cholesteric liquid crystal used has a selective reflection wavelength region in the visible region, to which a black dichroic dye is added. A light-reflecting layer to reflect the light in the selective reflection wavelength region of the cholesteric liquid crystal is formed on the opposite side of the cholesteric liquid crystal layer to the observation side. In the animation mode, a driving signal S1 consisting of a selecting signal to change the cholesteric liquid crystal into homeotropic alignment or focal conic alignment and a holding signal to hold the aligned state selected by the selecting signal are applied on the colesteric liquid crystal layer in each frame. When the static image mode is switched from the animation mode, the voltage on the cholesteric liquid crystal layer is reduced to zero. Therefore, the liquid crystal is subjected to transition from the homeotropic alignment to planar alignment, and the content of the display can be held without power supply by the bistability of the planar alignment and focal conic alignment. |
