Photographic lens system

摘要

A single focal length lens system has a first negative lens element and a last negative lens element. The first negative lens element is disposed at an object side end of the lens system and the object side surface thereof is concave. The last negative lens element is disposed at an image side end of the lens system. The lens system fulfills the following condition: <IMAGE> wherein phi f represents the refractive power of the first negative lens element; and phi 1 represents the refractive power of the last negative lens element.