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:
Sep. 23, 2003
Filed:
May. 10, 2001
Keith M. Kotchick, St. Paul, MN (US);
Ikuko Ebihara, St. Paul, MN (US);
Gregory E. Gilligan, Hastings, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A polarizer has low color shift and is particularly well suited to use in an LCD display. The polarizer has a double pass color shift of |&Dgr;x|≦0.005 and |&Dgr;y|≦0.005 for illumination by a C-illuminant, and a double pass contrast modulation of at least 90%. The display includes two or more layers stacked together, at least one of the layers being an absorbing polarizer having a double pass color shift of |&Dgr;x|≦0.005 and |&Dgr;y|≦0.005 for illumination by a C-illuminant. A polarizer with a selected color shift is also used with a rear projection screen having a dispersing layer stacked together with first absorbing polarizer. The polarizer has a single pass color shift with at least one of &Dgr;x and &Dgr;y being negative under illumination by a C-illuminant, and a polarization co-efficiency greater than 90%.