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:
Jul. 17, 1990
Filed:
Aug. 30, 1989
Applicant:
Inventors:
Karl Felle, Oberkochen, DE;
Heinz Krastel, Oberkochen, DE;
Assignee:
Carl-Zeiss-Stiftung, Heidenheim/Brenz, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ; G03B / ;
U.S. Cl.
CPC ...
3542341 ; 354 65 ; 354254 ;
Abstract
The invention is directed to a shutter wherein the rotary discs thereof are accelerated out of a standstill start position for each exposure operation and are again brought to standstill at the end of the exposure operation. The start position is computed such that a constant access time results for all exposure times. An electronic control circuit for the shutter includes a position-control circuit and a speed-control circuit. During each exposure operation, the drive for the rotary discs of the shutter are switched between the two control loops.