A lens system includes a first lens and a second lens formed in turn from an object side to an image side. The lens system satisfies the following conditions: 0.08.ltoreq.D2/D.ltoreq.0.14 (1) 4.ltoreq.h2/z2.ltoreq.12 (2) wherein, D2 is the distance along an optical axis of the lens system from the second surface of the first lens to the third surface of the second lens, D is the distance along an optical axis of the lens system from the first surface of the first lens to fourth surface of the second lens, h2 is the distance from the optical axis of the lens system to the outermost optically effective portion of the second lens surface of the first lens, and z2 is the distance along the optical axis of the lens system from the vertex of the second surface of the first lens to the point of the optical axis where h2 is measured.