Patent ID: 6362925
Filing Date: 2002-03-26
Classification: G02B

Abstract:
A zoom lens system of three-group construction comprising, in order from an object side thereof:a first lens group consisting of one single lens formed of a homogeneous medium and having positive refracting power; a second lens group consisting of one single lens formed of a homogeneous medium and having negative refracting power; and a third lens group consisting of one single lens formed of a homogeneous medium and having positive refracting power, wherein, for zooming from a wide-angle end to a telephoto end of said zoom lens system, at least said second lens group is adapted to be moved from said object side toward an image side of said zoom lens system; wherein, the three-group zoom lens system shall satisfy the following relation: fW3Tâ€ƒâ€ƒ(1) where fW is a focal length at which said zoom lens system has the shortest focal length, fT is a focal length at which said zoom lens system has the longest focal length and f3 is a focal length of the third lens group.