Patent · US Expired

Automatic exposure control for automatic-focus cameras

US4466718A · kind A · utility

5Cited by

6References

1Claims

0Family size

Assignee

Agfa-Gevaert NV · BE

Inventors

Peter Lermann · Feldkirchen-Westerham, DE
Istvan Cocron · Munich, DE
Gunter Fauth · Unterhaching, DE

Key dates

Filing date	Nov 12, 1980
Grant date	Aug 21, 1984
Priority date	—
Expiry date	Nov 12, 2000

Classification

Technology area (CPC G)Physics
CPC primaryG02B7/30
WIPO fieldOptics
WIPO sectorInstruments

Abstract

When a trigger lever is depressed, both a focus adjuster ring and a control disk commence to rotate in unison, driven by a spring mechanism. Position-sensing switches receive signals indicating which subject-distance setting the focus adjuster ring should be arrested at, and furthermore are opened and closed by the control disk during movement of the latter. When the focus adjuster ring reaches the required subject distance setting, it is arrested and kept arrested, thereby completing an automatic focussing operation, but the control disk continues to turn on to its end position, at which it causes the shutter mechanism of the camera to open and furthermore the exposure-timing circuit of the camera to initiation a scene-light-dependent exposure-timing operation.

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