Patent ID: 7898747
Filing Date: 2011-03-01
Classification: G02B

Abstract:
1. A thin type optical lens system for taking image comprising three lens elements with refractive power, from the object side to the image side: a first plastic lens element with positive refractive power having a convex aspheric object-side surface and a convex aspheric image-side surface; an aperture stop; a second plastic lens element with negative refractive power having a concave aspheric object-side surface and a convex aspheric image-side surface; a third plastic lens element with negative refractive power having a convex aspheric object-side surface and a concave aspheric image-side surface, and the third lens element being formed with at least one inflection point; wherein an on axis distance between the second lens element and the third lens element is T23, a center thickness of the third lens element is CT3, and they satisfy the relation: a radius of curvature of the object-side surface of the first lens element is R1, and a radius of curvature of the image-side surface of the first lens element is R2, and they satisfy the relation: