Patent ID: 7986286

Claim:
An organic electro-luminescent display comprising: a pixel unit to display an image corresponding to a scan signal, a light emission control signal, and a data signal, the image comprising frames; a scan driver to supply the scan signal and the light emission control signal to the pixel unit, according to a luminance control signal; a data driver to generate the data signal from video data and to supply the data signal to the pixel unit; a luminance control unit to control a pulse width of the light emission control signal using frame data values, which are sums of the video data input to each of the frames; and a power supply unit to supply a first voltage and a second voltage to the pixel unit, wherein the luminance control unit comprises: a data sum-up unit to generate the frame data values; a look-up table to store the frame data values and pulse widths of the light emission control signals corresponding to the frame data values; an operator unit to generate the look-up table comprising steps of luminance reduction, by using one of the frame data values corresponding to a beginning step of luminance reduction, one of the frame data values corresponding to a final step of luminance reduction, one of the pulse widths corresponding to the beginning step of luminance reduction, and one of the pulse widths corresponding to the final step of luminance reduction; and a luminance control signal driver to output the luminance control signal, corresponding to one of the pulse widths stored in the look-up table, to the scan driver, wherein the operator unit calculates a pulse width variation of the light emission control signal by using the frame data value corresponding to the beginning step of luminance reduction, the frame data value corresponding to the final step of luminance reduction, the pulse width corresponding to the beginning step of luminance reduction, and the pulse width corresponding to the final step of luminance reduction, wherein the operator unit calculates pulse widths corresponding the steps of luminance reduction other that the beginning step and the final step, using pulse width variation, and wherein the operator unit stores the calculated pulse widths in the look-up table, and the pulse width variation is determined by the following Equation 1, Pulse final - Pulse beginning Value final - Value beginning , Equation ⁢ ⁢ 1 wherein Pulse final represents the pulse width corresponding to the final step of luminance reduction, Pulse beginning represents the pulse width corresponding to the beginning step of luminance reduction, Value final represents the frame data value corresponding to the final step of luminance reduction, and Value beginning represents the frame data value corresponding to the beginning step of luminance reduction.