Patent ID: 6744564
Filing Date: 2004-06-01
Classification: G02B,H04N

Abstract:
A zoom lens comprising, in order from an object side thereof, a first lens group having negative refracting power, a second lens group having positive refracting power and a third lens group having positive refracting power, wherein for zooming from a wide-angle end to a telephoto end of the zoom lens upon focused on an infinite object point, the second lens group moves toward the object side alone and the third lens group moves in a locus different from that of the second lens group with a varying spacing between adjacent lens groups, wherein:the second lens group comprises two lens components, i.e., an object side-lens component and an image side-lens component, one of which is composed of a cemented lens component consisting of a positive lens element and a negative lens element and the other consists only of a positive single lens component, and the object side-lens component satisfies condition (1): 0.62FR/R2FF<1.05â€ƒâ€ƒ(1) where R2FF is an axial radius of curvature of an object side-surface of the object side-lens component in the second lens group, and R2FR is an axial radius of curvature of an image side-surface of the object side-lens component in the second lens group.