ZOOM LENS AND IMAGING APPARATUS

摘要

The zoom lens consists essentially of a positive first lens group, a negative second lens group, an aperture stop, a third lens group, a positive fourth lens group and a fifth lens group in this order from the object side. The first, third, and fifth lens groups are fixed while the second and the fourth lens groups move when changing magnification from the wide angle end to the telephoto end, and the fourth lens group moves when focusing is performed. The fifth lens group consists essentially only of a single cemented lens having a meniscus shape with a convex surface toward the image side, and conditional formulas (1), (2) are satisfied when the maximum image height is Y, the air equivalent back focus is Bf and the distance along the optical axis from the aperture stop to the peak of the most-image-side lens surface is Lsr:;0.05

主权项

1. A zoom lens consisting essentially of a first lens group having a positive refractive power, a second lens group having a negative refractive power, an aperture stop, a third lens group, a fourth lens group having a positive refractive power, and a fifth lens group in this order from the object side, wherein
the first, third, and fifth lens groups are fixed while the second and fourth lens groups move when changing magnification; the fourth lens group moves when focusing; the fifth lens group consists essentially only of a single cemented lens which has a meniscus shape with a convex surface toward the image side; the refractive index of a medium which constitutes the object-side lens of the cemented lens is greater than that of the image-side lens of the cemented lens; and the zoom lens satisfies conditional formulas (1) and (2) below:
0.05