To make a display without a flicker, lowering. etc., in a contrast ratio possible and to make high picture quality and low power consumption possible by changing a frame frequency according to a response speed of a display element in a liquid crystal display device simultaneously selecting several pieces of scanning lines among plural pieces of scanning lines and driving the display element.
For lowering the frame frequency, multi-line drive is performed, and the power consumption is reduced. An ATP method (a) including a regular liquid crystal making the frame frequency 45Hz and with the response speed 200ms is compared with the case (b) of the multi-line drive driving four pieces of scanning lines by simultaneous selection. In the ATP method (a), since a selection period is once in one frame, a change in transmissivity at an ON time is violent, and since the frame frequency is late also, a remarkably large flicker is observed. Further, the mean transmissivity at the ON time is reduced remarkably also. On the contrary, in the case (b) using a four line simultaneous selection method at the frame frequency of 45Hz, the selected number of times become four times to be dispersed uniformly to the whole frame period, and a voltage is applied to the liquid crystal uniformly.
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