Patent · US Expired

Measuring and control system for single lens reflex

US4118718A · kind A · utility

1Cited by

5References

2Claims

0Family size

Assignee

VEB Pentacon Dresden Kamera und Kinowerke · DE

Inventors

Werner Hahn · Dresden, DE
Heinz Schulze · Dresden, DE

Key dates

Filing date	Jun 21, 1977
Grant date	Oct 3, 1978
Priority date	—
Expiry date	Jun 21, 1997

Classification

Technology area (CPC G)Physics
CPC primaryG03B17/20
WIPO fieldOptics
WIPO sectorInstruments

Abstract

The exposure measuring system for single-lens reflex cameras, in which system the light passing through the objective lens is conveyed to the view finder eyepiece via a view finder reflex mirror, is provided with an additional mirror in the optical path of the camera, which additional mirror is partly translucent. A photo electric cell is pivotally mounted in order to be movable by linkage coupled with the reflex-mirror so that in one position during image viewing the cell receives light from the reflex mirror for light measurement and in another position during film exposure the cell receives light from the additional mirror for controlling exposure time.

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