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:
Jul. 29, 2008
Filed:
Feb. 12, 2003
Fred J. Roska, Woodbury, MN (US);
Richard C. Allen, Lilydale, MN (US);
Matthew B. Johnson, St. Paul, MN (US);
Steven J. Rhyner, St. Paul, MN (US);
William W. Merrill, White Bear Lake, MN (US);
Joan M. Strobel, Maplewood, MN (US);
Kevin M. Hamer, St. Paul, MN (US);
Gregory E. Gilligan, Hastings, MN (US);
Fred J. Roska, Woodbury, MN (US);
Richard C. Allen, Lilydale, MN (US);
Matthew B. Johnson, St. Paul, MN (US);
Steven J. Rhyner, St. Paul, MN (US);
William W. Merrill, White Bear Lake, MN (US);
Joan M. Strobel, Maplewood, MN (US);
Kevin M. Hamer, St. Paul, MN (US);
Gregory E. Gilligan, Hastings, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
An optical stack includes a first liquid crystal layer and a j-retarder disposed on the liquid crystal layer. The j-retarder includes a simultaneous biaxally stretched polymeric film being substantially non-absorbing and non-scattering for at least one polarization state of visible light. The j-retarder has x, y, and z orthogonal indices of refraction where at least two of the orthogonal indices of refraction are not equal, an in-plane retardance being 100 nm or less and an out-of-plane retardance being 50 nm or greater.