Patent · US Expired

Focus detection condition display device for camera

US4812912A · kind A · utility

30Cited by
5References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 18, 1987
Grant dateMar 14, 1989
Priority date
Expiry dateMay 18, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N23/635
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A focus detection condition display device suitable for use in a camera provided with an electronic viewfinder. The pattern signal corresponding to a focus detection zone on which focus detection is conducted by a focus detecting system is superimposed on the video signal of the object field and said signal is output to an electronic viewfinder. When the focus detection has become impracticable for such reason as lack of contrast of the object field, or focusing has become impracticable because of the object coming too close to the camera, an alarm is issued by the pattern corresponding to a focus detection zone displayed on the electronic viewfinder displaying in a manner different from that ordinarily used.

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