Wide-angle photographic lens system enabling correction of distortion

Abstract

A wide-angle photographic lens system enabling correction of distortion composed of four lenses, in which a first lens, an iris, a second lens, a third lens and a fourth lens sequentially arranged along an optical axis from an object, wherein the first lens has weak refractivity, the second lens has positive refractivity, the third lens has strong positive refractivity, and the fourth lens has negative refractivity, wherein the lens system satisfies relations, |f1/f|>4, f3/f<1.5, and te/tc<0.5, wherein f1 is a focal length of the first lens, f is a total focal length of all the lenses, f3 is a focal length of the third lens, to is a lens thickness on an effective diameter of a rear surface of the third lens, and tc is a center thickness of the third lens.

Dependencies are inferred from the claim text.