Patent · US Expired

Full/fill flash control system for cameras

US4772910A · kind A · utility

13Cited by
17References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 19, 1988
Grant dateSep 20, 1988
Priority date
Expiry dateJan 19, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B7/16
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An artificial illumination control system for controlling the energization of an electronic flash device during a photographic exposure interval in a camera automatically operates in a full flash mode whenever the ambient light level is too low for a proper daylight exposure and the camera-to-subject distance does not exceed a maximum distance suitable for a full flash exposure. Moreover, it automatically operates in a fill flash exposure whenever the ambient light level is bright enough that areas of the subject may be substantially shadowed and the camera-to-subject distance does not exceed a maximum distance small enough to ensure that the fill flash output will lighten the shadowed areas. The maximum distance for a fill flash exposure is always less than the maximum distance for a full flash exposure.

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