Patent ID: 6683591
Filing Date: 2004-01-27
Classification: G09G

Abstract:
A liquid crystal display device comprising:a matrix wiring of row wirings and column wirings; a liquid crystal pixel element at each cross point of the matrix wiring, the pixel element comprising a liquid crystal cell, switching transistor, and capacitor, a first terminal of the cell and a first terminal of the capacitor being connected at a joint point, which is in turn connected to one of the column wirings through the switching transistor, and a second terminal of the cell being connected to a reference potential; a video signal drive circuit for applying a video signal to each of the column wirings through a transfer switch; a selection signal drive circuit for applying a selection signal sequentially to each of the row wirings, the selection signal drive circuit, in cooperation with the video signal drive circuit, applying the video signal to the joint point of each pixel element through the transfer switch and the switching transistor to charge the capacitor of each pixel element by the video signal, wherein the video signal is a modified video signal derived from a normal video signal comprising an inverted video signal and a non-inverted video signal, said deriving occuring by shifting the DC level, or levels, of the inverted video signal and/or the non-inverted video signal so that the amplitude width of the modified video signal is narrower than that of the normal video signal; and a control circuit for applying a first potential to a second terminal of the capacitor at each pixel element in a first group for a first period, while the video signal is being applied to the joint point associated with each pixel in said first group, and for applying a second potential to the second terminal of the capacitor at each pixel element in a second group for at least part of a second period, while the video signal is not being applied to the joint point associated with each pixel element in said second group, wherein the first potential and the second potential are selected so that a charge built up in the capacitor at each pixel element in said second group provides a potential at the associated joint point which corresponds to the normal video signal by compensating for a DC shift in the second period.