| 摘要 |
A surface illuminant device includes a surface illuminant (1) having a light distribution characteristic with no directivity relative to specific directions, and a prism sheet (P, W) having a plurality of prisms each having a predetermined apical angle. The prism sheet is placed on the light emission side (a) of the surface illuminant (1). One side of the prism sheet (P, W) on which a plurality of prisms are placed is opposite to the light emission side (a) of the surface illuminant (1). Accordingly, light can be emitted in a plurality of specific directions in concentrative manner to enhance luminance in that plurality of directions. Further, the surface illuminant device includes an optical sheet (S) which condenses the incident light. In the luminance distribution (light distribution characteristic) thus obtained, the luminance gently decreases in the vicinity of the directions in which light is emitted in concentrative manner. <IMAGE>
|
