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:
Nov. 07, 2006
Filed:
Feb. 12, 2003
Richard C. Allen, Lilydale, MN (US);
Matthew B. Johnson, St. Paul, MN (US);
Fred J. Roska, Woodbury, 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);
John M. Klaeser, Greenville, SC (US);
Sebastian F. Zehentmaier, Greenville, SC (US);
Richard C. Allen, Lilydale, MN (US);
Matthew B. Johnson, St. Paul, MN (US);
Fred J. Roska, Woodbury, 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);
John M. Klaeser, Greenville, SC (US);
Sebastian F. Zehentmaier, Greenville, SC (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A process for making an optical film includes stretching a polyolefin film in a first direction and stretching the polyolefin film in a second direction different than the first direction forming a biaxially stretched polyolefin film. At least a portion of the stretching of the polyolefin film in the second direction occurs simultaneous with the stretching of the polyolefin film in the first direction. The biaxially stretched polyolefin film has a length and a width and substantially non-absorbing and non-scattering for at least one polarization state of visible light. The biaxially stretched polyolefin film 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.