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:
Jan. 24, 2017
Filed:
Feb. 11, 2014
3m Innovative Properties Company, St. Paul, MN (US);
Audrey A. Sherman, Saint Paul, MN (US);
Marie A. Boulos, West Saint Paul, MN (US);
Kevin R. Schaffer, Woodbury, MN (US);
Michael A. Meis, Stillwater, MN (US);
Thu-Van T. Tran, Maplewood, MN (US);
Ellen O. Aeling, Oakdale, MN (US);
Soemantri Widagdo, Depok, ID;
3M INNOVATIVE PROPERTIES COMPANY, Saint Paul, MN (US);
Abstract
Disclosed herein is an optical device having a light source, a viscoelastic lightguide and a retroreflective film suitable for retroreflecting light. Light from the light source enters the viscoelastic lightguide and is transported within the lightguide by total internal reflection. The transported light is extracted from the lightguide and retroreflected at a structured surface of the retroreflective film. The optical device may have a 'front lit' or a 'back lit' configuration depending on the relative positioning of the lightguide and the retroreflective film. The retroreflective film may include prismatic retroreflective sheeting, holographic film or film structured with diffraction gratings. The optical device may be used, for example, as a sign or marking, a license plate assembly, a tail light assembly for vehicles, a security laminate for protection of documents against tampering, or an illumination device.