To provide a surface light source device in which luminance unevenness is efficiently reduced and which has uniform brightness and a high front luminance, and a transmission type display device equipped with the same.
The surface light source device is provided with a first optical control sheet 14 in which a plurality of first unit lenses 141 are arranged in vertical direction and a second optical control sheet 15 which is arranged on an outgoing light side rather than the first optical control sheet 14 and in which a plurality of second unit lenses 151 are arranged in horizontal direction. The second optical control sheet 15 is formed along the surface convex shape of the second unit lenses 151, and has a second scattering layer 152 to scatter light. The scattering characteristics by the scattering component other than the lens shape of the second unit lenses 151 of the second optical control sheet 15 is larger than the scattering characteristics by the scattering component other than the lens shape of the first unit lenses 141 of the first optical control sheet 14, and the thickness W2 of the second optical control sheet is formed thicker than the thickness W1 of the first optical control sheet 14. A transmission type display device 10 is equipped with this.
KODAMA DAIJIRO
Ryoichi Takaoka
Hayashi Ichiyoshi
Kiyoshi Kato