摘要 |
PURPOSE:To display a stable halftone by successively applying prescribed pulses to a display element, and controlling a high frequency AC pulse to be superposed on a display pulse in accordance with the gradation of display. CONSTITUTION:A pulse P1 including a DC pulse component is first applied to the display element to set ferroelectric liquid crystal to the saturation reverse response state, and a pulse where a high frequency AC pulse P2 is superposed on a DC pulse V, which is symmetrical to the DC pulse having a voltage -V and has the opposite polarity, is next applied to the display element to set ferroelectric liquid crystal to a desired response state including the halftone and the average voltage level applied to the display element is set to zero. Thereafter, the high frequency AC pulse P2 is applied to keep the desired response state. Thus, blackening of transparent electrodes, discoloring of bicolor coloring matters, and degradation of liquid crystal do not occur even if a device is driven for a long time, and the halftone is stably displayed.
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