发明授权
- 专利标题: Optical device, light-condensing backlight system, and liquid crystal display
- 专利标题(中): 光器件,聚光背光系统和液晶显示器
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申请号: US10556688申请日: 2004-04-15
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公开(公告)号: US07593079B2公开(公告)日: 2009-09-22
- 发明人: Kentarou Takeda , Naoki Takahashi , Kazutaka Hara , Takahiro Fukuoka
- 申请人: Kentarou Takeda , Naoki Takahashi , Kazutaka Hara , Takahiro Fukuoka
- 申请人地址: JP Ibaraki-shi
- 专利权人: Nitto Denko Corporation
- 当前专利权人: Nitto Denko Corporation
- 当前专利权人地址: JP Ibaraki-shi
- 代理机构: Westerman, Hattori, Daniels & Adrian, LLP.
- 优先权: JP2003-140444 20030519
- 国际申请: PCT/JP2004/005386 WO 20040415
- 国际公布: WO2004/104653 WO 20041202
- 主分类号: G02F1/1335
- IPC分类号: G02F1/1335 ; G02F1/13
摘要:
An optical element of the invention comprises at least three laminated circular-polarization-type-reflection polarizers (a) whose wavelength bands for selective reflection of polarized light overlap one another; a layer (b1) which is placed between at least a pair of the circular-polarization-type-reflection polarizers (a) and has a front retardation of substantially zero (in the normal direction) and a retardation of at least λ/8 with respect to incident light inclined by at least 30° relative to the normal direction; and a layer (b2) which is placed between at least another pair of the circular-polarization-type-reflection polarizers (a) and has a front retardation of substantially zero (in the normal direction) and a retardation of at most λ/2 with respect to incident light inclined by 60° relative to the normal direction. The optical element condenses or collimates incident light from a light source and can control transmission of light at large incident angles relative to the normal direction, increase front brightness and reduce coloration.