| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent occurrence of luminance unevenness caused by patterns formed in a transmittance distribution layer, and suppress optical absorption in the transmittance distribution layer, and to stably maintain characteristics of the transmittance distribution layer. <P>SOLUTION: A diffusion plate 121 diffuses incident light inside and transmit it. A light source part 110 includes a plurality of LEDs 111 arranged on the light source surface and emits light toward the incident face of the diffusion plate 121. A reflection sheet 113 makes reenter the reflection light from the incident face of the diffusion plate 121 to the incident face by reflection. A transmittance distribution sheet 122 made of a transparent material is arranged opposed to the emitting face of the diffusion plate 121, has a flat face and a structure face, and a plurality of fine structure parts formed on the structure face are arranged to form a plurality of groups corresponding to each of the plurality of LEDs 111. In the respective groups formed, the shape of the individual fine structure parts is established according to the distance from the light sources corresponding to the groups, and the shape becomes closer to flat as the distance increases. <P>COPYRIGHT: (C)2012,JPO&INPIT |
