Patent ID: 8654110

Claim:
A display device of matrix type, comprising: photosensors, provided in a display region, each for outputting a signal corresponding to an intensity of light emitted to the photosensor; thin-film transistors of n-channel type, the thin-film transistors each serving as a source follower including a gate to which the signal is inputted; light intensity detecting means for detecting the intensity of the light by detecting an output of the source follower, which is the thin-film transistor; and a capacitor having a first end connected with the gate and a second end which is opposite to the first end, wherein each thin-film transistor includes a drain to which a first pulse signal having a first pulse is inputted, the first pulse rising from a low level to a high level in a state where the signal is inputted to the gate of the thin-film transistor, and the second end of the capacitor which is opposite to the first end is configured to receive a second pulse signal having a second pulse as an input, the second pulse rising from a low level to a high level before a timing at which the first pulse rises, and the second pulse falling from the high level to the low level after the timing at which the first pulse rises.