Patent ID: 6456442
Filing Date: 2002-09-24
Classification: G02B

Abstract:
A zoom lens system comprising a positive first lens group, a positive second lens group, and a negative third lens group, in this order from an object;wherein each of said three lens groups is independently moved, along the optical axis, upon zooming so that the distances therebetween become shorter; and wherein said zoom lens system satisfies the following relationships: 0.03d12Wâˆ’d12T)/fW<0.15 16.64&lE;KF<20 â€ƒwherein d12W designates the distance between the most image-side surface of said first lens group and the most object-side surface of said second lens group, at the short focal length extremity; d12T designates the distance between the most image-side surface of said first lens group and the most object-side surface of said second lens group, at the long focal length extremity; fW designates the focal length of the entire zoom lens system at the short focal length extremity; KF=(fT/fFT)2 fT designates the focal length of the entire zoom lens system at the long focal length extremity; and fFT designates the resultant focal length of said first lens group and said second lens group at the long focal length extremity.