Patent ID: 7365912

Claim:
A zoom lens system consisting of: a first lens group having a negative refractive power; a second lens group having a positive refractive power; and a third lens group having a positive refractive power, wherein the first through third lens groups are sequentially arranged from an object side toward an image side, the first, second, and third lens groups move when magnification changes between wide-angle and telephoto, a refractive index G1n of at least one lens element of the first lens group satisfies 1.92<G1n<2.00, and wherein when a distance that the second lens group moves when the magnification changes from the wide-angle position to the telephoto position is represented by L II , a focal length of the zoom lens optical system at the wide-angle position is represented by f w , and the focal length of the zoom lens optical system at the telephoto position is represented by f t , 0.8 < L II f t ⁢ f w < 1.0 is satisfied.