Patent ID: 7460315

Claim:
A lens system comprising, in the order from the object side: a positive refractive power first lens; a negative refractive power second lens; and a negative refractive power third lens, wherein the lens system satisfies the following conditions: D/TTL> 1.2; (1) 4.5 >R 1 R/R 1 F> 2.2; and (2) f/R 1 F> 3, (3) wherein, D is the diameter of a maximal image circle of the lens system on an image plane of the lens system, TTL is a distance from a surface of the first lens facing the object side of the lens system to the image plane, R 1 R is the radius of curvature of a surface of the first lens facing the image side of the lens system, R 1 F is the radius of curvature of the surface of the first lens facing the object side of the lens system, and f is a focal length of the lens system.