Display device having a photosensor and a correction sensor

Abstract

It is an object of the present invention to allow a specified function to be readily selected in a mobile telephone or the like without performing a complicated operation. A liquid crystal () is sandwiched between a TFT substrate () and a color filter substrate (). A photosensor TFT () for selecting the function is disposed on the periphery of an effective screen of the TFT substrate (). A window () is provided in a portion of the color filter substrate corresponding to the photosensor TFT (), and the outside light is blocked as a result of the user touching a finger to the window. A signal from the photosensor is used for selecting the function. A correction sensor TFT () is disposed adjacent to the photosensor TFT (), to thereby eliminating noise caused by the temperature distribution, stray light, or the like, and erroneous operation of the photosensoris prevented.