Patent ID: 8330684

Claim:
An organic light emitting display comprising: a pixel portion, including a plurality of pixels, to express images corresponding to a scan signal, an emission control signal, and a data signal; a scan driver to transfer the scan signal and the emission control signal to the pixel portion; a data driver to generate and transfer a plurality of data signals to the pixel portion using video data; a frame memory to store only one frame of video data and transfer the video data in frame periods to the data driver; a luminance controller to control pulses of the emission control signal using frame data, the frame data being a sum of video data stored in the frame memory; and a power supply unit to supply voltages of first and second power sources to the pixel portion; wherein the luminance controller controls the number and widths of the pulses of the emission control signal in accordance with the sum of the video data and controls an emission time and a non-emission time of the pixel portion according to a range of luminance of the pixel portion, when the range of luminance is below a predetermined value the emission time and non-emission time of the pixel portion are increased, decreasing the number of pulses of the emission control signal and increasing the width of the pulses of the emission control signal, and when the range of luminance is above the predetermined value the emission time and non-emission time of the pixel portion are decreased, increasing the number of pulses of the emission control signal and decreasing width of the pulses of the emission control signal, wherein both the increase of the emission time and non-emission time of the pixel portion and the decrease of the emission time and non-emission time of the pixel portion are accomplished using the luminance controller, said luminance controller being a single driver circuit consisting solely of a data summing unit, a look-up table and a luminance control signal driver, wherein the video data includes red, green, and blue components, wherein the data summing unit sums the video data stored in the frame memory to generate the frame data, wherein the look-up table designates the number and widths of pulses in the emission control signal corresponding to the video data, and wherein the luminance control signal driver generates a luminance control signal in accordance with the number and widths of the pulses in the emission control signal.