Patent ID: 8723899

Claim:
A liquid crystal display comprising: a liquid crystal display panel on which data lines and gate lines cross each other; a data driving circuit configured to convert data of an input image into positive and negative analog data voltages and output the positive and negative analog data voltages to the data lines; a gate driving circuit configured to sequentially supply a gate pulse synchronized with the data voltages to the gate lines; and a timing controller configured to supply the input image data to the data driving circuit, control an operation timing of each of the data driving circuit and the gate driving circuit, compare the input image data with a previously stored reference data pattern, and decide whether the input image data is the same as the reference data pattern, wherein when the input image data is the same as the reference data pattern, the timing controller recognizes the input image data as a first problem pattern, disables an operation for counting data of a white gray level, and controls horizontal polarities of the data voltages output from the data driving circuit in a horizontal 1 dot inversion scheme, wherein when the input image data is not the same as the reference data pattern, the timing controller recognizes the input image data as a second problem pattern, enables the operation for counting the data of the white gray level, decides a shift of a common voltage based on a count value, and controls the horizontal polarities of the data voltages output from the data driving circuit in a horizontal 2 dot inversion scheme so as to minimize the shift of the common voltage.