According to one embodiment, a detection device includes a substrate, a light detector, a light emitter. The substrate is light-transmissive. The light emitter is provided between the substrate and the light detector. The light emitter includes a first electrode, a light-emitting layer, and a plurality of second electrodes. The first electrode is provided between the light detector and the substrate. The first electrode is light-transmissive. The light-emitting layer is provided between the light detector and the first electrode. The second electrodes are provided between the light detector and the light-emitting layer.
