Zoom lens and optical apparatus having the same

Abstract

A zoom lens of the rear-focus type includes, in order from an object side to an image side, a first lens unit of positive refractive power, a second lens unit of negative refractive power, a third lens unit of positive refractive power and a fourth lens unit of positive refractive power. The variation of magnification from a wide-angle end to a telephoto end is effected by moving the second lens unit toward the image side. Shifting of an image plane caused by the variation of magnification is compensated for by moving the fourth lens unit. Focusing is effected by moving the fourth lens unit. The second lens unit consists of, in order from the object side to the image side, a negative lens, a negative lens, a positive lens and a negative lens, the third lens unit comprises a plurality of positive lenses and a negative lens, and the fourth lens unit consists of a negative lens and a positive lens, and wherein the following condition is satisfied: 0.25<(Fm−Fw)/(Ft−Fw)<0.45 where Fm is a focal length of the entire zoom lens in a position where the fourth lens unit has moved a maximum distance during the variation of magnification with focusing on an infinitely distant object, Fw is a focal length of the entire zoom lens at the wide-angle end, and Ft is a focal length of the entire zoom lens at the telephoto end.

Dependencies are inferred from the claim text.