Patent ID: 8564514
Filing Date: 2013-10-22
Classification: G09G

Abstract:
1. A method for driving a liquid crystal display device having a common electrode, a plurality of pixel electrodes distributed along each of a plurality of scanning lines, a liquid crystal material having spontaneous polarization sealed between the common electrode and the plurality of pixel electrodes, switching elements provided for the plurality of pixel electrodes, respectively, for controlling voltage application to the liquid crystal material, and a back-light for generating light, said method comprising the steps of: writing image data by applying a voltage in a first voltage application to the liquid crystal material corresponding to each of the plurality of pixel electrodes and a second voltage application to the liquid crystal material corresponding to each of the plurality of pixel electrodes, in each frame; and erasing the image data by applying a plurality of different voltages having different voltage levels discretely to the liquid crystal material corresponding to each of the plurality of pixel electrodes to make a voltage value of the liquid crystal material become zero, wherein during the erasure of image data, a single batch selection is performed by applying a gate signal to at least two or all of the plurality of scanning lines, and each of the different voltages is applied simultaneously to the pixel electrodes corresponding to the at least two or all of the plurality of scanning lines in a period of the single batch selection for erasing the image data and equalizing the voltages being applied to the liquid crystal material between the common electrode and each of the plurality of pixel electrodes, the batch selection being performed periodically, the different voltages are applied separately during the single batch selection, a first of the different voltages having a value not smaller than a maximum value of the voltage applied in writing the image data and a different polarity than the voltage applied in writing the image data, and the last of the different voltages having a same value as a voltage on the common electrode, the plurality of the scanning lines for erasing data are selected simultaneously during the erasure of the data, the back-light, within each frame, is turned on after the first voltage application and from substantially at an end of the second voltage application to the liquid crystal material corresponding to each of the plurality of pixel electrodes during the writing of the image date, and turned off at a start of the erasing of the image data, and wherein further during the erasure of the data image, a time of application of the last of the different voltages is set to be equal to or less than one tenth of a time of application of the first of the different voltages.