SURFACE LIGHT SOURCE DEVICE

PROBLEM TO BE SOLVED: To suppress luminance irregularity of a surface light source device.SOLUTION: A surface light source device 100 includes a first light guide plate 10a, a second light guide plate 10b, a reflection sheet 12, a first light source 8a, a second light source 8b, and a light source drive circuit 19. The first light guide plate has a light guide part 23a and a first optical control part 16a which is provided on a farther side from the first light source than the light guide part and deflects light in a specific direction to emit it from the first light guide plate. The second light guide plate has a second optical control part 16b deflecting light in a specific direction and emitting it from the second light guide plate and a translucent part 23b provided on a farther side from the second light source than the second optical control part. The first light guide plate and the second light guide plate are arranged in the way that the first optical control part overlaps the translucent part in its lamination direction and the second optical control part overlaps the light guide part, and in a planar view, are arranged so that at least no gap appears between one end sides of the first optical control part and the second optical control part.SELECTED DRAWING: Figure 1 【課題】面光源装置の輝度ムラを抑制すること。【解決手段】面光源装置１００において、第１導光板１０ａ、第２導光板１０ｂ、反射シート１２、第１光源８ａ、第２光源８ｂおよび光源駆動回路１９を含む。第１導光板は、導光部２３ａと当該導光部よりも第１光源から遠い側に設けられており光を特定方向へ偏向させて第１導光板から出射させる第１光学制御部１６ａを有する。第２導光板は、光を特定方向へ偏向させて第２導光板から出射させる第２光学制御部１６ｂと当該第２光学制御部よりも第２光源から遠い側に設けられた透光部２３ｂを有する。第１導光板と第２導光板は、その積層方向において、第１光学制御部と透光部とが重なるとともに第２光学制御部と導光部とが重なるように配置されており、かつ、平面視において第１光学制御部と第２光学制御部の各々の一端側同士の間に少なくとも隙間が生じないように配置されている。【選択図】図１