| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens, suitable for an image pickup device using a solid-state image pickup element by fully separating an exit pupil from an image surface over the entire variable power region. SOLUTION: This zoom lens has a 1st group having negative refractive power, an aperture diaphragm, a 2nd group having positive refractive power and a 3rd group having positive refractive power, in this order starting from an object side; and varying power from a wide angle end to a telephoto end, the space between the 1st group and the aperture diaphragm is narrowed, the space between the aperture diaphragm and the 2nd group is narrowed, and the space between the 2nd group and the 3rd group is widened. The 1st group has a negative meniscus lens, whose concave surface faces an image side and a positive meniscus lens whose convex surface faces the object side. The 2nd group has at least one positive lens and at least one negative lens; and furthermore, the zoom lens satisfies each of the conditional expressions, if Dw represents the space between the aperture diaphragm and the 2nd group at the wide angle end, Dt represents the space between the aperture diaphragm and the 2nd group at the telephoto end and fw represents a focal distance at the wide angle end.
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