| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a zoom lens which offers a high zoom ratio, compactness of the entire system, and superior optical performance throughout an entire zoom range.SOLUTION: A zoom lens includes, in order from the object side to the image side, first through third lens groups having positive, negative, and positive refractive power, respectively. At the telephoto end, the first lens group is located further on the object side and the second lens group is located further on the image side relative to respective positions at the wide-angle end. Distance between each adjacent pair of lens groups changes when zooming. A distance Dt23 between the second lens group and the third lens group at the telephoto end, focal lengths fw, ft of the entire system at the wide-angle end and telephoto end, a focal length f2 of the second lens group, displacement M2 of the second lens group in an optical axis direction when zooming from the wide-angle end to the telephoto end, and a focal length f3 of the third lens group are each set appropriately.</p> |
