Patent ID: 7301516

Claim:
A display device, comprising: a comparing portion extracting a minimum value and a maximum value of red, green, blue source image data signals; a first extracting portion extracting an intermediate signal from the minimum value and extracting a white image data signal from the intermediate signal; a second extracting portion extracting a red image data signal from the intermediate signal, the maximum data signal, and the red source image data signal; a third extracting portion extracting a green image data signal from the intermediate signal, the maximum data signal, and the green source image data signal; fourth extracting portion extracting a blue image data signal from the intermediate signal, the maximum data signal, and the blue source image data signal; and display panel having a plurality of pixels including red, green, blue, and white sub-pixels supplied with the red, green, blue, and white image data signals, respectively, wherein the first extracting portion includes a fifth extracting portion extracting the intermediate signal using a first function, W=f(MIN), wherein W is a value of the intermediate signal and MIN is the minimum value of the red, green, blue source image data signals, and the a sixth extracting portion extracting the white image data signal using a second function, Wo=f(W), wherein Wo is a value of the white image data signal and W is a value of the intermediate signal.