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:
Dec. 14, 1999
Filed:
Jul. 27, 1998
Roland Krueger, Wolfenbuettel, DE;
Rollei Fototechnic GmbH, Braunschweig, DE;
Abstract
The invention relates to a method for controlling an electronically directly driven focal-plane shutter which has two lightproof curtains, each of which is associated with, and controlled by, an electric drive motor. The drive motors move the curtains across an image field. One curtain starts in a closed position, and the other curtain starts in an open position prior to taking the exposure. So as to achieve operating sequences of the two curtains which are as identical as possible, both drive motors initially are driven simultaneously in an 'open' direction. The curtain which starts in the open position first is pressed against a defined open-position stop. Then, by reversing the associated drive motor, that curtain is moved in the 'close' direction to complete the exposure.