| 摘要 |
PURPOSE:To eliminate deterioration due to a DC component by making the width of a voltage pulse applied to liquid crystal invariably constant during a nonselection period and also setting the mean value of DC components of positive and negative voltages pulses to zero. CONSTITUTION:Scanning electrodes 23 and signal electrodes 24 are provided in a lattice shape on the opposite surfaces of a couple of substrates 21 and 22, and liquid crystal is oriented. The liquid crystal is ON in a selection period t10 and OFF in t20. In the selection periods, the 1st voltage pulses V2.t13 and (V2-V4).t24 larger than a saturation value are applied firstly. Then, the 2nd voltage pulse (V1-V4).t14 larger than the saturation value in one polarity direc tion in the ON state or (V1-V3).t24 less than the threshold value of the liquid crystal in the OFF state is applied. Further, the 3rd voltage pulses are applied in a selection period t15(t25). In nonselection periods t11 and t21, on the other hand, the ON or OFF waveform of a signal electrode waveform 202 in t10 or t20 is applied. Consequently, there is neither a contrast decrease nor a flicker as shown by optical response 204.
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