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:
Jan. 11, 2000
Filed:
May. 27, 1997
Hans Baumann, Raisdorf, DE;
Raytheon Anschutz G.m.b.H., , DE;
Abstract
The invention refers to a method of shortening the closure time of shutters in cinema projectors of the type in which film is intermittently advanced one frame at a time into registry with an image window in the projector, and wherein each time the film is advanced a shutter in the projector closes the image window during the time that the film is being advanced. According to the invention, an optical compensation of the film motion is effected by determining the rate at which each image of the film begins and ends, respectively, its advance into registry with the image window of the projector, generating a control signal proportionate to the rate, and positioning between the image window and the associated projection screen a movable plane-parallel plate which is adjsuted by the control signal to shorten the closure time of the image window during each film advance, thereby to increase the luminous efficiency factor of the projector.