Patent ID: 6570716
Filing Date: 2003-05-27
Classification: G02B

Abstract:
A zoom lens optical system having a zoom ratio of 3 or greater and comprising, in order from an object side thereof, a first lens group having positive refracting power and a second lens group having negative refracting power in which, for zooming from a wide-angle end to a telephoto end of the zoom lens optical system, the respective lens groups move toward the object side with a decreasing spacing between the first lens group and the second lens group, wherein:said first lens group consists of, in order from an object side thereof, a first lens component (U1) having negative refracting power, a second lens component (U2) having positive refracting power and a third lens component (U3) having positive refracting power wherein each lens component consists of a single lens or a doublet, and satisfies the following: 0.35G1/f12<1.5â€ƒâ€ƒ(1) where fG1 is a focal length of the first lens group, and f12 is a focal length of the second lens component.