| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a planar light source device having a structure hardly causing luminance irregularity between planar light source units adjacent to each other. <P>SOLUTION: This planar light source device 40 illuminating a transmission type liquid crystal display device from the back is provided with a diffuser plate 61, and a light transmission control member 100 comprising a plurality of light transmission control member units 110. Each light transmission control member unit 110 is provided with a plurality of first inclined surfaces 111, a plurality of second inclined surfaces 112 and a plurality of optical thin films 113 of which the optical transmittance is changed depending on an incident angle of light. Light emitted from a light source 41 and directed toward the first inclined surfaces 111 penetrates the optical thin films 113 formed on the first inclined surfaces 111 and enters into the diffuser plate 61; at least a part of light directed toward an adjacent light transmission control member unit 110' is reflected by an optical thin film 113' in the adjacent light transmission control member unit 110', and returned into a planar light source unit 42. <P>COPYRIGHT: (C)2008,JPO&INPIT |
