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. 20, 2005
Filed:
Apr. 12, 2004
Simon Magarill, Cincinnati, OH (US);
Charles L. Bruzzone, Woodbury, MN (US);
Stephen K. Eckhardt, White Bear Lake, MN (US);
R. Edward English, Jr., Cincinnati, OH (US);
E. Gregory Fulkerson, Amelia, OH (US);
Jiaying MA, Maplewood, MN (US);
Todd S. Rutherford, Cincinnati, OH (US);
Simon Magarill, Cincinnati, OH (US);
Charles L. Bruzzone, Woodbury, MN (US);
Stephen K. Eckhardt, White Bear Lake, MN (US);
R. Edward English, Jr., Cincinnati, OH (US);
E. Gregory Fulkerson, Amelia, OH (US);
Jiaying Ma, Maplewood, MN (US);
Todd S. Rutherford, Cincinnati, OH (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A compound polarization beam splitter () for use with a reflective, polarization-modulating, imaging device (), e.g., a LCoS device, is provided. The compound PBS has: (a) an input prism (); (b) an output prism (), and (c) a polarizer (), which is located between the two prisms () and which may be a wire grid polarizer () or a multi-layer reflective polarizer (). Polarized illumination light () enters the input prism () through a first surface () and undergoes total internal reflection at a second surface () before being reflected from the polarizer () and polarization-modulated at the imaging device (). The polarizer's tilt angle (β) is less than 45°, which reduces astigmatism and the required back working distance of the system's projection lens ().