| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a backlight device with distance from a center of a light source to a diffusion plate short, and capable of reducing illuminance unevenness without deterioration of the illuminance even in the case of reducing the number of optical sheets. <P>SOLUTION: Illumination light emitted from a light source 3 is condensed and scattered by a diffusion plate with a prism 11 with projection prisms 13 formed at a predetermined interval on a surface. Next, the illumination light is condensed and emitted by a condensing sheet with a prism 12 with a prism 15 formed on a surface. Here, the projection prisms 13 and the prism 15 are formed in an emission direction of the illumination light, and bottom angles of the projection prisms 13 are in a range between 50 degrees or more and 70 degrees or less. <P>COPYRIGHT: (C)2011,JPO&INPIT |
