Patent ID: 6961034

Claim:
A liquid crystal display device comprising: pixel electrodes; a common electrode; a plurality of data lines and a plurality of gate lines intersecting each other; a plurality of switchers, provided for the pixel electrodes, for supplying signals from the data lines to the pixel electrodes; a gate line driver for scanning the gate lines; a data line driver for driving the data lines, in accordance with the gradation to be displayed; and a controller for controlling the gate line driver and the data line driver, wherein the controller comprises a signal absence detector for detecting that at least one of a video signal, a horizontal synchronization signal, and a vertical synchronization signal is no longer being input to the liquid crystal display device, wherein in response to a detection by the signal absence detector that one of the signals is no longer being input while power is being supplied to the liquid crystal display, the controller outputs a signal to the gate line driver to make all the gate lines active for a predetermined time and the controller outputs a signal to the data line driver to supply the same electric potential as applied to the common electrode to all the data lines for the predetermined time, wherein, after discharging of the liquid crystal display, the controller outputs signals to the gate line driver and the data line driver for making the gate line driver and the data line driver return to a state before the discharging was performed, and wherein the predetermined time, during which time all the gate lines are active and during which time the same electric potential as applied to the common electrode is applied to all the data lines, is determined based on time constants of a resistor and a capacitor.