| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a variable power optical system that has an appropriate vibration-proofing function. <P>SOLUTION: A variable power optical system S1 includes first and second lens elements that can shift so as to include vertical components with respect to an optical axis, and when varying power from a wide-angle end state to a telephoto end state, any one of first or second lens elements shifts so as to include vertical components with respect to the optical axis according to a change in the focal distance and performs image plane correction to satisfy conditions of the following expressions. ¾fB¾<¾fA¾, fw≤fh≤(¾fB¾/¾fA¾)×ft×1.50, (¾fB¾/¾fA¾)×ft×0.05≤fk≤ft [where, fA: the focal distance of the first lens element, fB: the focal distance of the second lens element, fw: the focal distance of the whole variable power optical system under a wide-angle end state, ft: the focal distance of the whole variable power optical system under a telephoto end state, fh: the focal distance of the whole variable power optical system in performing image plane correction by the first lens element, fk: the focal distance of the whole variable power optical system in performing image plane correction by the second lens element]. <P>COPYRIGHT: (C)2012,JPO&INPIT |
