Patent ID: 8760419

Claim:
A touch substrate comprising: a base substrate; a first sensing element which senses a first light, wherein the first sensing element comprises: a first active pattern disposed on the base substrate; a first sensing source electrode disposed on the first active pattern; a first sensing drain electrode disposed on the first active pattern and spaced apart from the first sensing source electrode; and a first sensing gate electrode disposed on the first sensing source electrode and the first sensing drain electrode; and a first variable voltage part which provides at least one of a first sensing gate voltage and a second sensing gate voltage to the first sensing gate electrode of the first sensing element based on reception of the first light, wherein a level of the second sensing gate voltage is higher than a level of the first sensing gate voltage, wherein the first variable voltage part comprises a first variable source electrode, a first common drain electrode and a second variable source electrode spaced apart from one another on a first common active pattern, the first sensing gate electrode electrically connected to the first common drain electrode.