Patent ID: 8711489

Claim:
A zoom lens of a fixed total length comprising: a first lens group having a negative refractive power; a second lens group having a negative refractive power; a third lens group having a positive refractive power; a fourth lens group having a negative refractive power; and a fifth lens group having a positive refractive power; arranged in the above mentioned order from the object side to the image side; wherein, at the time of changing the magnification from the wide-angle end toward the telephoto end; the first lens group is anchored; while the second lens group is moved; and the third lens group and the fourth lens group are moved so as to be located at the object side of the telephoto end relative to the wide-angle end; in such a way that the interval between the second lens group and the third lens group is decreased at the telephoto end relative to the wide-angle end; the interval between the third lens group and the fourth lens group is increased at the telephoto end relative to the wide-angle end; and the interval between the fourth lens group and the fifth lens group is increased at the telephoto end relative to the wide-angle end; and, at the time of focusing a near object point from a remote object point, the second lens group is moved; and, the zoom lens satisfies the conditional formula (1-1) shown below: 0.5<( d 45 T−d 45 W )/ fW< 2.0 (1-1), where d45W is the interval between the fourth lens group and the fifth lens group at the wide-angle end on the optical axis; d45T is the interval between the fourth lens group and the fifth lens group at the telephoto end on the optical axis; and fW is the focal length of the entire zoom lens system at the wide-angle end.