| 摘要 |
PROBLEM TO BE SOLVED: To provide an image reader thinned and miniaturized at low cost and enhancing the quality of fingerprint or read images in a document. SOLUTION: There are formed, in a first optical element part 14 and a second optical element part 15: respective first reflecting surfaces 14c, 14d, 15c, 15d for reflecting light rays emitted from LEDs 12a-12d and for converting the rays into approximately cylindrical wave-shaped light rays that diverge two-dimensionally; and respective second reflecting surfaces 14e, 15e for converting the light rays reflected by the first reflecting surfaces 14c, 14d, 15c, 15d into approximately plane wave-shaped reflected rays pointed in a certain direction. The first reflecting surfaces 14c, 14d, 15c, 15d of small areas converge the diffusion of the illuminating light rays in a one-dimensional direction before the light rays from the LEDs 12a-12d diffuse greatly three-dimensionally. The light rays are applied in such a manner that the illuminances per unit area of the second reflecting surfaces 14e, 15e become approximately equal. The light rays are then reflected in approximately parallel directions by the second reflecting surfaces 14e, 15e, are totally reflected, and applied to the subject of reading. COPYRIGHT: (C)2007,JPO&INPIT
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