A cellular phone has a black-and-white LCD that displays characters and communication
information and a color LCD that displays an image. The image and the characters
are displayed on the separate LCDs. Thus, the characters are not superimposed on
the image, and they are easy to see. When the image is not needed (the user is
not using the phone or the user is talking on the phone), only the black-and-white
LCD displays the characters and the color LCD is turned off to save energy.