Patent attributes
A planar lighting device according to an embodiment has a light source, a light guide plate, and a light shielding sheet. The light guide plate has an light-incident surface on one edge surface and a light-emitting surface on one main surface. The light guide plate emits light, which is emitted by the light source and entered from the light-incident surface, from the light-emitting surface. The light guide plate further has a plurality of through-holes that are spaced apart from each other in a direction intersecting a direction in which light emitted by the light source enters into the light-incident surface. The through-holes pass through the light guide plate in a thickness direction. The light shielding sheet is disposed so as to cover a portion on the light-emitting surface between adjacent through-holes.