Patent ID: 8075151

Claim:
A surface light source device comprising: a diffusing member which diffuses light; a reflective member which reflects light; plural light sources provided aligned in a flat manner between the diffusing member and the reflective member; and a light control member provided between the plural light sources and the reflective member as well as arranged in a state that a gap is imposed between the reflective member and the light control member, which has a light-guiding function of guiding part of light emitted from respective light sources in an alignment direction of the light sources, and wherein the light control member has a rugged structure portion in which geometric shapes in cross section are continuously formed on at least one surface, wherein the light control member has the rugged structure portion at a surface of a side facing the reflective member, and wherein the light control member is arranged in the state that apexes of convex portions included in the rugged structure portion are allowed to abut on a reflective surface of the reflective member.