Patent ID: 8638503

Claim:
A zoom lens comprising: a first lens group having a positive refractive power; a second lens group having a negative refractive power; a third lens group having a negative refractive power and comprised of a single negative meniscus lens with a concave surface on an object side, to move along an optical axis for focusing; a fourth lens group having a positive refractive power; a fifth lens group having a positive refractive power, the first to fifth groups being arranged along the optical axis in order from an object side; and an aperture stop disposed between the third lens group and the fourth lens group, wherein: when zooming from a wide angle end to a telephoto end, the zoom lens is moved so that an interval between the first and second lens groups increases, an interval between the second and third lens groups increases, an interval between the third and fourth lens groups decreases, and an interval between the fourth and fifth lens groups decreases; and the fourth and fifth lens groups are set to have a combined lateral magnification to satisfy the following condition, when an object distance is infinite at a telephoto end: −0.041<β 45T /Ft<− 0.025 where Ft is a focal length of the entire zoom lens at the telephoto end and β 45T is combined lateral magnification of the fourth and fifth lens groups.