Patent ID: 7138972

Claim:
A drive method for a liquid crystal device during a frame period comprising the steps of: (a) applying a scanning signal to each of a plurality of scanning electrodes, said scanning signal including a selection signal during a selection period and a non-selection signal during a non-selection period; and (b) applying a data signal to each of a plurality of signal electrodes based on the waveform of said scanning signal and on display data representing an image having a gray scale to be displayed by the liquid crystal device; wherein step (a) further includes the step of: (1) grouping the plurality of scanning electrodes into p groups, wherein p is an integer of at least two; (2) applying the selection signal substantially simultaneously to the plurality of scanning electrodes in one of the p groups and applying the non-selection signal substantially simultaneously to the plurality of scanning electrodes in one of the p groups immediately after applying the selection signal thereto, wherein the selection signal is sequentially applied to succeeding groups of the scanning electrodes, wherein the non-selection signal is sequentially applied to succeeding groups of the scanning electrode groups immediately after applying the selection signal thereto, wherein each of the scanning signals has N selection periods and N non-selection periods per frame, wherein N is a integer of at least two, and applying the selection signal to each of the scanning electrodes in each of the N selection periods; and (c) applying a weighted voltage in accordance with the display data in each of the selection periods; wherein the display data comprises q bits, q being a positive integer, wherein each of the N selection periods is divided further into k portions, k being a positive integer greater than q, and wherein at least one of the k portions is allocated to the display data corresponding to one of the bits to reduce the number of applied voltage levels.