Patent · US Expired

Image pickup lens system

US6466377B1 · kind B1 · utility

16Cited by
4References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 6, 2000
Grant dateOct 15, 2002
Priority date
Expiry dateSep 6, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B13/24
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An image pickup lens system according to the present invention includes a diaphragm, a first lens which has a convex fact formed on the side of an image surface in the vicinity of an optical axis and which has a positive power and radii of curvature at a center, whose signs are not opposite from each other, a second lens which has a convex face formed on the side of an object in the vicinity of the optical axis and which has a negative power and radii of curvature at a center, whose signs are not opposite from each other, and a third lens which has a convex face formed on the side of the image surface in the vicinity of the optical axis and which has a positive power. The diaphragm and the first, second and third lenses are disposed sequentially from the side of the object, and the first face of at least the second lens being formed into an aspherical shape. Thus, each of various aberrations can be corrected satisfactorily, while maintaining a desired optical performance and ensuring a wider angle of view, and the image pickup lens system can be produced easily.

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