Patent ID: 8243005

Claim:
An apparatus for driving a lamp of a liquid crystal display device comprises: a plurality of lamps to irradiate light to a liquid crystal display panel; a lamp driver supplying a high voltage alternating current (AC) signal to, and controlling brightness of the plurality of lamps of the liquid crystal display panel, wherein the lamp driver comprises: an inverter to receive: an external direct current (DC) signal and a pulse generated from a Pulse Width Modulator controller, wherein the inverter converts the external direct current signal into the high voltage alternating current signal, wherein the Pulse Width Modulator controller controls and adjusts based on a feedback signal, at least one of a duty cycle ratio and an amplitude of the high voltage alternating current signal to correspond to a specified reference brightness in accordance with a characteristic of the liquid crystal display panel during a scanning period, wherein the scanning period is prior to a picture implementing period; and a timing controller to generate a brightness variation signal based on a brightness determination of input video signal, and supplies the brightness variation signal to the Pulse Width Modulator controller during the picture implementing period, wherein the brightness variation signal causes the Pulse Width Modulator controller to adjust the at least one of the duty cycle ratio and the amplitude of the high voltage alternating current signal based on a high and a low brightness of a picture implemented by the liquid crystal display panel: wherein during the scanning period, the lamp driver allots a value corresponding to a specific reference brightness in accordance with the characteristic of the liquid crystal display panel, wherein the apparatus compensates for a delay time within the scanning period by supplying a voltage to a liquid crystal material to uniformly activate the liquid crystal display panel in advance, wherein during the scanning period, if the on-time duty cycle ratio of the pulse generated from the Pulse Width Modulator controller is small or the on-time duty cycle ratio of the pulse is unchanged, increase the amplitude of the pulse to correspond to the specific reference brightness, and if the on-time duty cycle ratio of the pulse is large, decrease the amplitude of the pulse, wherein the specific reference brightness is determined by an experimental result and a statistical result in accordance with the characteristic of the liquid crystal display panel, wherein the brightness of the lamp can be compensated to correspond to the specific reference brightness, wherein during the scanning period, after determining a specific output power in accordance with the specific reference brightness, adjust the amplitude of the pulse of the Pulse Width Modulator controller to correspond to the determined specific output power, and wherein during the scanning period, if the on-time duty cycle ratio of the pulse is unchanged, adjust the amplitude of the pulse to correspond to the determined specific output power.