发明名称 |
Lighting device, image-reading device, color-document reading apparatus, image-forming apparatus, projection apparatus |
摘要 |
A lighting device includes an illumination face having a length and a width; a light-emitting element having a light-ray-releasing face the maximum length of which is equal to or less than the width of the illumination face; and a light-source unit that has an optical element which changes the direction of light rays released from the light-emitting element to be directed to the illumination face. The optical element has a concave-face reflecting unit having a cross section that is shaped into a quadratic curve or a pseudo quadratic curve, which is placed at least on one portion thereof, and a luminance distribution on the illumination face has a flat portion that is equal to or not less than a predetermined width.
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申请公布号 |
US7438443(B2) |
申请公布日期 |
2008.10.21 |
申请号 |
US20040942908 |
申请日期 |
2004.09.17 |
申请人 |
RICOH COMPANY, LIMITED |
发明人 |
TATSUNO HIBIKI;NISHINA KIICHIRO |
分类号 |
F21V7/00;G03B27/54;G02B9/34;G06T1/00;H01L33/50;H01L33/58;H01L33/60;H04N1/028;H04N1/04 |
主分类号 |
F21V7/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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