Patent ID: 7755847
Filing Date: 2010-07-13
Classification: G02B

Abstract:
1. A zoom lens system, in order from the object side to the image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power, the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element, in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and the following conditions (1), (I-2) and (5) are satisfied: (wherein, 3.2<f where, αi n n r r d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element, ω f f