Patent · US Expired

Electrooptical focusing apparatus for photographic cameras

US4200786A · kind A · utility

2Cited by
4References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 24, 1978
Grant dateApr 29, 1980
Priority date
Expiry dateJan 24, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B7/36
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An apparatus for electrooptically focusing the objective in a single lens reflex camera provided with a focusing screen and a split image wedge rangefinder, where focus detectors are used in which an image segment is scanned in an image plane. The focusing window of the focusing screen provided with a split image wedge rangefinder (5) is followed by a pentaprism (8) having a first plane reflecting surface which is partly reflecting. The scanning grating (14) and the photoelectric detector system (17,18) are mounted in the direction of the light beam behind this plane surface of the pentaprism and along the optical axis deflected by one of the wedges (5a) and an optics (11) is present along the optical axis to image the plane of one of the wedges (5a) into that plane where the scanning takes place.

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