According to one embodiment, a display device comprises a collimating layer including first to third openings, first to third color filters overlaid on the first to third openings, respectively, a first sensor outputting a first detection signal corresponding to light made incident through the first opening and the first color filter, a second sensor outputting a second detection signal corresponding to light made incident through the second opening and the second color filter, and a third sensor outputting a third detection signal corresponding to light made incident through the third opening and the third color filter.