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. 02, 2009
Filed:
Dec. 08, 2005
Charles L. Bruzzone, Woodbury, MN (US);
David J. W. Aastuen, Shoreview, MN (US);
Michael P. Keyes, Minneapolis, MN (US);
Charles L. Bruzzone, Woodbury, MN (US);
David J. W. Aastuen, Shoreview, MN (US);
Michael P. Keyes, Minneapolis, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A projection system includes an image-forming device and a polarizing beamsplitter. Illumination light illuminates the image-forming device via the first polarizing beamsplitter. A retardation element is disposed between the image-forming device and the polarizing beamsplitter. A bias controller applies a bias to pixels of the image-forming device in the dark state so as to substantially maximize contrast in image light reflected from image-forming device. In some arrangements, the volume between the polarizing beamsplitter and the image-forming device is sealed, with the retarding element being disposed within the sealed volume and being attached to either the polarizing beamsplitter or the image-forming device.