Patent ID: 8094382

Claim:
A zoom lens system comprises a negative first lens group, a positive second lens group and a positive third lens group, in this order from an object, wherein upon zooming from the short focal length extremity to the long focal length extremity, each of said negative first lens group, said positive second lens group and said positive third lens group is moved along the optical axis of said zoom lens system; wherein said negative first lens group comprises a negative first lens element, a negative second lens element, and a positive third lens element, in this order from the object; wherein said positive second lens group comprises a cemented lens comprising a positive first lens element and a negative second lens element in this order from the object, and a meniscus lens element having the concave surface facing toward the image, in this order from the object; and wherein said zoom lens system satisfies the following conditions: −0.4 <f 23 /f 24<0.4 0.7 <f 3 /ft <1.3 wherein f 23 designates the combined focal length of the cemented lens of said positive second lens group; f 24 designates the focal length of said meniscus lens element, of said positive second lens group, having the concave surface facing toward the image; f 3 designates the focal length of said positive third lens group; and ft designates the focal length of the entire zoom lens system at the long focal length extremity.