Patent ID: 7869142
Filing Date: 2011-01-11
Classification: G02B

Abstract:
1. An optical lens system for taking image comprising, in order from the object side to the image side: a first lens element with positive refractive power having a convex object-side surface; a plastic second lens element with negative refractive power having a concave object-side surface and being provided with at least one aspheric surface; a plastic third lens element with negative refractive power having a concave object-side surface and being provided with at least one aspheric surface; a fourth lens element with positive refractive power having a concave image-side surface, inflection points being formed on the fourth lens element; and an aperture stop being located between an object to be photographed and the second lens element, an on-axis distance between the first lens element and the second lens element being T in the optical lens system for taking image, the number of the lens elements with refractive power being limited to four.