| 摘要 |
An image reading lens is provided and includes: first, second and third lens groups arranged on the object side with respect to the aperture stop; and fourth, fifth and sixth lens groups arranged on the image side. At least all positive lenses, in each lens group, satisfy conditional expression (1) below. At least two positive lenses of the first to third lens groups and at least two positive lens of the fourth to sixth lens groups satisfy the conditional expression (2) below. In the conditional expressions, vd represents Abbe number at the d-line, and Deltatheta<SUB>g,d </SUB>represents abnormal dispersion. <?in-line-formulae description="In-line Formulae" end="lead"?>vd>60.0 (1)<?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>Deltatheta<SUB>g,d</SUB>>0.015 (2)<?in-line-formulae description="In-line Formulae" end="tail"?>
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