Patent · US Expired

Photographic camera with focussing system which time-multiplexes the signals from plural photodetectors

US4221474A · kind A · utility

6Cited by

3References

22Claims

0Family size

Assignee

Agfa-Gevaert NV · BE

Inventors

Peter Lermann · Feldkirchen-Westerham, DE
Istvan Cocron · Munich, DE
Eduard Wagensonner · Aschheim, DE
Kurt Borowski · Aschheim, DE
Theodor Huber · Munich, DE

Key dates

Filing date	Jan 22, 1979
Grant date	Sep 9, 1980
Priority date	—
Expiry date	Jan 22, 1999

Classification

Technology area (CPC G)Physics
CPC primaryG02B7/32
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

An infrared measuring beam is emitted from the camera towards the subject, and reflected back as a tiny light spot projected, by an optics which transversely shifts in dependence upon exposure-objective subject-distance setting, onto one, the other or both of two infrared photodiodes. The signals from the two photodiodes are transmitted in processed form to two output flip-flops through the intermediary of a single, shared signal-processing stage, employing time-division-multiplexed transmission of the two photodiode signals, to assure that the signal processing of the two photodiode output signals be as identical as possible.

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