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:
Apr. 22, 2003
Filed:
Feb. 07, 2001
Sithya S. Khieu, Eden Prairie, MN (US);
Gregory E. Gilligan, Hastings, MN (US);
Thomas R. Borden, Oakdale, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
The present disclosure relates to improved raised pavement markers having a totally-internal-reflective lens. The disclosure also relates to methods of manufacturing the raised pavement marker. The raised pavement markers described below include a housing connected to a totally-internal-reflective lens. The totally-internal-reflective lens includes a retroreflective element having a smooth surface generally opposite a plurality of cube corner elements. A film is attached to the retroreflective element at the apexes of the cube corner elements to form spaces, i.e., an air gap, between the film and the cubes. The film and retroreflective element cooperate to form the totally-internal-reflective lens. Light entering the retroreflective element through the smooth surface is retroreflected at the cube/air interface. Methods of manufacturing include, for example, forming a shell with the retroreflective element and attaching the film to the apexes of the cube corner elements.