Lens optical system

Abstract

A wide-angle lens optical system, including, in a sequence from an object side, a first lens group having a positive or negative refractive power, a stop, and a second lens group having positive refractive power, wherein the first lens group comprises, in a sequence from the object side, a front group having negative refractive power and a rear group having positive refractive power, and the wide-angle lens optical system satisfies the following Inequalities: 1.0 < f II f < 1.45 0.6 ≤  f Ia f Ib  < 1.5 where f denotes the overall focal distance of the lens optical system, fII denotes the focal distance of the second lens group, fIa denotes the focal distance of the front group of the first lens group, and fIb denotes the focal distance of the rear group of the first lens group.

Dependencies are inferred from the claim text.