Variable power optical system, imaging apparatus, and digital apparatus

摘要

A small high]-definition variable power optical system having a variable power ratio of about two to three times; an imaging apparatus including the variable power optical system; and digital equipment mounted with the imaging apparatus are provided. The variable power optical system, consisting of a plurality of lens groups, for performing variable power by changing the distance between each lens groups in an optical axis direction is configured by two or more lens groups, each having negative or positive optical power, arranged in such order from the object side. The first lens group is a cemented lens configured by at least one negative lens and at least one positive lens arranged in order from the object side. At least one aspherical surface is arranged to each of the first lens group and the second lens group. A third lens group having a positive optical power is arranged on the image plane side of the second lens group.