Patent · US Expired

Exposure factor setting device for a camera

US4121231A · kind A · utility

3Cited by
3References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 23, 1977
Grant dateOct 17, 1978
Priority date
Expiry dateFeb 23, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B7/087
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An exposure factor setting device for a photographic camera comprising manually adjustable shutter speed and diaphragm aperture setting components, an indicator cooperative with a shutter speed scale and capable of responding to either of the outputs of the shutter speed setting component and an exposure value computer, and first and second gates connected respectively between the shutter speed setting component and the indicator and between the computer and the indicator and arranged to be acted on alternately in sequence by a common pulse generator. When the previously selected combination of shutter speed and diaphragm aperture is not correct in conformity with the prevailing scene brightness, the indicator is caused to flicker between two positions for the automatic and manual shutter speed values. To attain correct adjustment of shutter speed and diaphragm aperture, the photographer may operate with either of the shutter speed and diaphragm aperture setting components until the amplitude of flickering of the indicator is reduced to zero, while looking through the finder as the indicator is visible in or adjacent the finder image field.

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