US Patent 9057868 Optical lens system

An optical lens system includes an aperture stop and an optical assembly, the optical assembly includes, in order from an object side to an image side: a first lens element with a positive refractive power; a second lens element with a negative refractive power; a third lens element with a positive refractive power; a fourth lens element with a positive refractive power; a fifth lens element with a negative refractive power; the aperture stop is located between an image-side surface of the first lens element and an object to be photographed. The optical lens system satisfies the following conditions: 0.55<TD/CA52<0.73; 20<Vd3−Vd2<40; 80<FOV<100; and 1.0<TL/ImgH<1.6.