Patent ID: 8348446

Claim:
An area light source device, comprising: a plate-shaped light guide plate that has one surface that serves as a transmissive surface and another surface that is on the opposite side from the transmissive surface, the light guide plate being partitioned into a plurality of light-emitting areas, wherein the light-emitting areas are defined by lines joining a plurality of recessed portions, and; and are laid out by arranging the plurality of the light-emitting areas such that they abut one another such that the plurality of recessed portions are in the surface on the opposite side of the transmissive surface, and provided along the perimeters of the light-emitting areas, wherein the recessed portions are disposed at the vertices or midpoints of the sides of the light-emitting areas; and at least three light-emitting elements that are accommodated in each of the recessed portions, each light-emitting element having one planar light-emitting face whose plane extends in a direction that is normal to the direction in which the light guide plate extends and faces toward the central region of a light-emitting area; that emits light in a direction in which the light guide plate extends and in a direction orthogonal to the planar light-emitting face of the light-emitting element; and wherein planes of the three planar light emitting faces in the recessed portion are angularly oriented such that each of the three planes are facing non-opposing different directions.