| 摘要 |
[Problem] To design a four-group zoom lens so as to minimize the change in angle of view when zooming and also achieve a sufficiently small form factor, sufficiently low weight, and sufficiently high performance. [Solution] This zoom lens comprises first, second, third, and fourth lens groups (G1-G4) having positive, negative, negative, and positive refractive power, respectively. The first lens group (G1) comprises an eleventh lens group (G11) that has negative refractive power and remains fixed when focusing, a twelfth lens group (G12) that has positive refractive power and moves when focusing, and a thirteenth lens group (G13) that has positive refractive power and remains fixed when focusing. The eleventh lens group (G11) comprises negative meniscus lenses (L1, L2), the concave surfaces of both of which face the image side, and a cemented lens wherein a biconcave lens (L3) on the object side and a biconvex lens (L4) on the image side are cemented together. The focal length (f1) of the first lens group (G1) and the distance (D4) between the second negative meniscus lens (L2) and the cemented lens satisfy the relation 0.60 < D4/f1 < 2.0. |
