According to one embodiment, a display device includes a first substrate including a first insulating substrate, a second substrate including a second insulating substrate, a light modulation layer, a first electrode of a strip shape extending in a first direction, a plurality of conductive wiring lines extending in a second direction crossing the first direction, configured to selectively transmit a desired polarized light component of incident light, a second electrode configured to optically change the light modulation layer in cooperation with the first electrode, and a detection circuit configured to detect a change in capacitance between the first electrode and the conductive wiring lines.