| 摘要 |
PROBLEM TO BE SOLVED: To provide an illumination optical system capable of suppressing generation of color unevenness in the illumination optical system using a white LED light source having an LED chip, and a first phosphor which emits light by being excited by light of the LED chip as a light source and an image reader using the same. SOLUTION: The illumination optical system is constituted so that a curved mirror 22 is used, a dichroic coat layer 22D (first reflection part) is formed on the front surface 22b of the curved mirror 22, a reflection layer 22M (second reflection part) is formed on the rear surface 22c of the curved mirror 22, and the illumination optical system has long pass filter characteristics as the dichroic coat layer 22D. Furthermore, since curvature radius R2 of the rear surface 22c of the curved mirror 22 is considered as the one shorter than curvature radius R1 of the front surface 22b of the curved mirror 22, it becomes possible to irradiate an irradiated part 24 by making blue right and yellow light into approximately equivalent illuminance, and to appropriately suppress the generation of the color unevenness by the curved mirror 22. COPYRIGHT: (C)2011,JPO&INPIT
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