Patent · US Expired

Focus detecting system using multiple portions of the image to be focussed

US4857720A · kind A · utility

17Cited by
4References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 27, 1988
Grant dateAug 15, 1989
Priority date
Expiry dateDec 27, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B7/346
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A focus detecting system which comprises photoelectric transducer element arrays for sensing standard and reference light fluxes which have passed respectively through different areas of an exit pupil of a photo-taking lens. The photoelectric transducer element arrays are comprised of a plurality of photoelectric transducer element arrays different in at least position or direction, some of the photoelectric transducer element arrays being arranged at a position containing the optical axis of the photo-taking lens whereas the remaining photoelectric transducer element arrays are arranged at a position which does not contain the optical axis. The direction of the photoelectric transducer element arrays is substantially perpendicular to the imaginary line which is drawn to connect between the optical axis and the position at which the photoelectric transducer element arrays outside the optical axis are arranged.

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