A method of adjusting color balance includes writing first to third adjustment video signals on first to third pixels, respectively to obtain first to third monochromatic data, updating the first to third adjustment video signals based on the first to third monochromatic data, writing the updated first to third adjustment video signals on the first to third pixels to obtain a mixed color data, updating the first to third adjustment video signals in the case where the mixed color data is within a tolerance and the power consumption exceeds a predetermined upper limit, and setting the first to third adjustment video signals updated finally as the maximum values of the video signals to be written on the first to third pixels, respectively.