| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain: a document reader of small size; and a high-angle-of-view document reading lens which is used for the document reader, and is sufficiently corrected in various aberrations such as curvature of field. Ž<P>SOLUTION: The document reader includes: the document reading lens that forms an image of image information on a document surface illuminated with a luminous flux from a light source means; and a reading means disposed on the image forming surface of the document reading lens, in which a plurality of pixels for photo-electrically converting image information are arranged in a one-dimensional direction. The final lens closest to the reading means in the document reading lens has at least one anamorphic face. If the curvature radius of the anamorphic face in the direction of the bus line in the position where the principal ray furthest outside the axis passes is represented by R(y), its curvature radius in the direction of a child line is represented by r(y), the focal length of the entire system of the document reading lens is represented by f, the image forming magnification is represented by β, and the maximum value of the image reading height on the document surface is represented by Y, the document reader satisfies conditional formulae expressed by 1.51<r(y)/R(y)<2.50 and -1.2<Y×β/f<-.0.8. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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