Patent ID: 6307685
Filing Date: 2001-10-23
Classification: G02B

Abstract:
A zoom lens, comprising:a plurality of lens groups, wherein the plurality of lens groups consists of, in the order named from an object side:(a) a first lens group having a positive focal length;(b) a second lens group having a negative focal length and at least one positive lens; and(c) a third lens group having a positive focal length,wherein a magnification is changed by moving said second and third lens groups in an optical axis direction of said zoom lens, and wherein the following condition is satisfied,3.0<Lt/(LZ)<6.0where Lt represents a distance between a lens surface closest to the object side of said first lens group and an image plane, L represents a diagonal length of the image plane, and Z represents a variable magnification ratio showing a ratio of a focal length at a wide angle end to a focal length at a telephoto end.