Patent · US Active

Optical lens system for taking image

US7692877B2 · kind B2 · utility

125Cited by

3References

20Claims

0Family size

Assignee

LARGAN PRECISION CO., LTD. · TW

Inventors

Hsiang-Chi Tang · Taichung, TW
Chun-Shan Chen · Taichung, TW

Key dates

Filing date	Aug 2, 2008
Grant date	Apr 6, 2010
Priority date	—
Expiry date	Nov 13, 2028

Classification

Technology area (CPC G)Physics
CPC primaryG02B13/18
WIPO fieldOptics
WIPO sectorInstruments

Abstract

An optical lens system for taking image comprises four lens elements from the object side to the image side: a first lens element with positive refractive power having a convex object-side surface; a second lens element with negative refractive power having a concave object-side surface and a concave image-side surface, at least one of the object-side surface and the image-side surface of the second lens element being aspheric, inflection points being formed on the image-side surface of the second lens element; a third lens element with positive refractive power having a convex object-side surface and a convex image-side surface; a fourth lens element with negative refractive power; and an aperture stop being located between the object side and the second lens element.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.