Patent ID: 7782279

Claim:
An organic light emitting diode display device, comprising: a pixel unit including a plurality of pixels to display an image by receiving a plurality of scan signals, a plurality of light emitting controlling signals, and a plurality of data signals; a scan driver to transmit the scan signals and the light emitting controlling signals to the pixel unit; a data driver to generate the plurality of data signals using video data and to transmit the data signals to the pixel unit; a brightness controller to output a brightness control signal controlling a brightness limiting range of the pixel unit based on the light emitting area of the pixel unit in accordance with a frame data which is the sum of the video data input in a frame; and a gamma correcting unit to control a ratio of brightness to gray scale using any one of a first gamma correcting value and a second gamma correcting value, the gamma correcting unit comprising a first register to store the first gamma correcting value and a second register to store the second gamma correcting value and to select one of the first register and the second register according to the brightness controller.