Patent ID: 7423817
Filing Date: 2008-09-09
Classification: G02B

Abstract:
1. An image pickup lens comprising three lenses, characterized in that the lenses comprise a first lens L 1 having a convex surface facing a subject side and positive refracting power, an aperture S, a second lens L 2 having a convex surface facing an image side and and having a negative refracting power, and a third lens L 3 having positive refracting power, which are disposed sequentially from the subject side as well as all the lens surfaces are composed of an aspheric surface and the following conditional formulas (A0) and (A1) are satisfied: where, f: focal length of the overall lens system f2: focal length of the second lens L R21: radius of curvature of the subject side lens surface of the second lens L R22: radius of curvature of the image surface side lens surface of the second lens L 2 .