Patent ID: 8350835
Filing Date: 2013-01-08
Classification: G01J,G02F,G06F,H01L,H04N

Abstract:
1. A display device provided with an active matrix substrate, and comprising: a photosensor provided on the active matrix substrate; sensor driving bus line connected to the photosensor; a sensor driving circuit that supplies a sensor driving signal to the photosensor via the sensor driving bus line; an amplifier circuit that amplifies sensor output that has been read out from the photosensor in accordance with the sensor driving signal, and outputs the amplified sensor output as a photosensor signal; and a signal processing circuit that processes the photosensor signal that has been output from the amplifier circuit, wherein the photosensor includes a photodiode, a capacitor that is connected to the photodiode, the capacitor including a semiconductor junction or a Schottky junction, and at least one switching element, the sensor driving bus line includes at least reset signal bus line that supplies a reset signal to the photosensor, and readout signal bus line that supplies a readout signal to the capacitor, due to the sensor driving circuit switching ON the readout signal after a predetermined time has elapsed since switching ON the reset signal, a photosensor signal that is in accordance with an amount of light received by the photosensor in the predetermined time is output to the signal processing circuit, and wherein the sensor driving circuit is configured to vary the capacitance of the capacitor through changing the bias voltage across the capacitor between a bias potential higher than a threshold potential determined by the junction in the capacitor and a bias potential lower than the threshold potential.