Patent ID: 9207441
Filing Date: 2015-12-08
Classification: G02B

Abstract:
1. A zoom lens comprising, in order from the object side: a first lens unit having a negative refractive power; a second lens unit having a positive refractive power; and a third lens unit having a positive refractive power, wherein the first lens unit comprises a negative lens and a positive lens, a total number of moving lens units in the zoom lens is 3, a total number of lenses in the first lens unit is 2, and the zoom lens satisfies the following conditional expressions (1) and (4): where Σd 13 is the total sum of the thickness of the lenses included in the first to third lens units of the zoom lens on the optical axis, and f t is the focal length of the entire zoom lens system at the telephoto end, where f w is the focal length of the entire zoom lens s stem at the wide angle end and m 2G is the amount of shift of the second lens unit on the optical axis during zooming from the wide angle end to the telephoto end.