The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 28, 1977
Filed:
May. 10, 1976
AGFA-Gevaert, A.G., Leverkusen, DT;
Abstract
An exposure control for still cameras wherein a first portion of a diaphragm shutter is movable from cocked position to one of several second positions for effecting admission of scene light to an unexposed film frame, and a second portion of the shutter is movable from a first to a second position subsequent to movement of first shutter portion from the cocked position to terminate the exposure. The aperture size and the exposure time can be varied within a first range of light intensities which is monitored by a first photoresistor. The exposure time, at a selected aperture size, can be varied within a second range of light intensities which is monitored by a second photoresistor. The second range is contiguous to and merges gradually into the first range. The characteristic of the second photoresistor within the second range of light intensities can be changed by a wedge-like filter which is mounted in front of the second photoresistor and whose position can be changed by a pivotable or rotary selector of f/stops. The selector, or the first portion of the shutter, can actuate a switchover device which connects the first photoresistor in parallel with a first fixed resistor when the selector selects a first f/stop, and which connects the first photoresistor in parallel with a second resistor when the selector selects a different f/stop. The characteristic of the second photoresistor within the second range of light intensities can be varied by the filter in such a way that a curve which is indicative of variations of resistance of the second photoresistor within the second range of light intensities in a first position of the selector is substantially parallel to a curve which is indicative of variations of resistance of the second photoresistor within the second range of light intensities in a different position of the selector.