Patent ID: 7768490

Claim:
A liquid crystal display for receiving and displaying an image signal, wherein the image signal comprises a horizontal line signal with a plurality of pixel data, and two adjacent pixel data of the pixel data have opposite polarities, the liquid crystal display comprising: a timing controller, comprising: a lookup table having a plurality of built-in common voltage compensation values; a data analyzer for performing an analysis of a gray scale distribution of the horizontal line signal and providing a value control signal from the lookup table according to an analysis result based on a comparison between an amount of the even pixel data and an amount of the odd pixel data having a gray scale value in a gray scale value range, wherein the value control signal corresponds to one of the common voltage compensation values; and a polarity selector for providing a polarity control signal according to the analysis result of the data analyzer; a compensation circuit for providing a common voltage compensation signal according to the value control signal and the polarity control signal; and a display panel for receiving the horizontal line signal and the common voltage compensation signal, and compensating a common voltage by the common voltage compensation signal to display the horizontal line signal.