Patent ID: 8044900

Claim:
A liquid crystal display device (LCD), comprising: a liquid crystal panel having a plurality of gate lines, a plurality of data lines, and a plurality of common voltage supply lines, wherein the liquid crystal panel is divided into a plurality of blocks, each having at least two common voltage supply lines; a plurality of gate driver integrated circuits (ICs) connected to the plurality of gate lines; a plurality of data driver ICs connected to the plurality of data lines; a plurality of common voltage compensators configured to supply compensated common voltages to the common voltage supply lines of the corresponding blocks; a common voltage generator connected to the common voltage compensators and configured to generate a predetermined common voltage directly supplied to the common voltage compensators, wherein each common voltage compensator includes an input terminal connected to one of the at least two common voltage supply lines and an output terminal connected to another of the at least two common voltage lines, and wherein each compensated common voltage has a phase opposite to that of a distorted common voltage from the one common voltage supply line with respect to the predetermined common voltage from the common voltage generator, and is supplied to the another common voltage supply line, wherein the input terminals of the common voltage compensator are respectively connected to both the common voltage generator and the last common voltage supply line of each block, the output terminal of the common voltage compensator is connected to the first common voltage supply line of each block, wherein the common voltage compensator generates the compensated common voltage as comparing the distorted common voltage supplied from the last common voltage supply line with a predetermined common voltage supplied from the common voltage generator, and then the common voltage compensator supplies the compensated common voltage to the first common voltage supply line of each block, wherein the common voltage compensator includes an operational amplifier, wherein the distorted common voltage is supplied to the inversion input terminal of the operational amplifier and the predetermined common voltage is supplied to the non- inversion input terminal of the operational amplifier, and then the compensated common voltage is generated from the output terminal of the operational amplifier, wherein each of the common voltage compensators is built into each of the corresponding gate driver ICs or data driver ICs, and wherein the distorted common voltage is supplied to each common voltage compensator through the last common voltage supply line of each block before the start of a second frame.