1. An image display device, comprising: a plurality of pixels; a pixel detection unit configured to detect first pixels having same R, G, and B gray scale values for a predetermined time or more among the plurality of pixels, using an image data supplied from an outside source of the image display device; a gray scale value calculation unit configured to calculate average gray scale values of the respective R, G and B of the first pixels and average gray scale values of corresponding R, G and B of second pixels, the second pixels being included in a predetermined area around the first pixels, using the image data; a data correction unit configured to correct the R, G and B gray scale values of the first pixels included in the image data, using the calculated average gray scale values of the respective R, G and B of the first pixels and the average gray scale values of the corresponding R, G and B of the second pixels; and a data driver configured to receive the corrected R, G and B gray scale values of the first pixels, to generate corrected image data with the corrected R, G and B gray scale values of the first pixels, and to supply the corrected image data to each pixel of the plurality of pixels.