| 摘要 |
PROBLEM TO BE SOLVED: To provide a large-aperture, wide-angle imaging lens with little distortion aberration.SOLUTION: An imaging lens comprises a first lens group 1G having a positive refractive power, a second lens group 2G having a negative refractive power, a third lens group 3G having a positive refractive power, and a fourth lens group 4G having a positive refractive power. In zooming from the wide angle end to the telephoto end, each of the lens groups moves in such a way that a distance between the first lens group 1G and the second lens group 2G increases and a distance between the second lens group 2G and the third lens group 3G decreases, while a distance between the third lens group 3G and the fourth lens group 4G varies. The third lens group 3G comprises: a cemented triplet lens 31 comprising a positive lens 31a, a negative lens 31b, and a positive lens 31c sequentially arranged in this order; a positive lens 32 located on the object side of the cemented triplet lens 31; and a cemented doublet lens 33 which is located on the image side of the cemented triplet lens 31 and comprises a negative lens 33a and a positive lend 33b. |
