| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a direct backlight device capable of attaining a high uniformity ratio of luminance by suppressing periodically uneven luminance of a light emitting surface while maintaining a high effective utilization factor of light flux, by devising the components of the direct backlight device. <P>SOLUTION: In this direct backlight device equipped with a plurality of linear light sources disposed side by side, a reflector, a light diffusing plate, and a prism sheet, it is preferable that the light diffusing plate has prism bar lines having serrate cross-sections on its one side further away from the light source, the vertical angle of the prism is not less than 60° and not more than 170°, and its pitch is not less than 20μm and not more than 700μm, and it is also preferable that the prism sheet has prism bar lines having serrate cross-sections on its one side further away from the light diffusing plate, the vertical angle of the prism is not less than 70° and not more than 120°, and its pitch is not less than 20μm and not more than 700μm. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
