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:
Sep. 04, 2001
Filed:
Jun. 25, 1998
David G. Freier, St Paul, MN (US);
Neal T. Strand, Woodbury, MN (US);
Scott R. Kaytor, Minneapolis, MN (US);
Frank L. Deyak, Stillwater, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A low-loss, diffuser film is provided for translucent surface(s) of lighted signage. The film has little absorptivity and has partial transmissivity and partial reflectivity. Luminance efficiency and brightness are significantly improved over conventional films used in backlit signage. A luminance efficiency prediction equation is also provided to aid in selection of diffuser films and interior surfaces of the lighted sign cavity. A combination of effects of diffuser films and a diffuse reflective films lining the interior surfaces of the lighted sign cavity is unexpectedly greater than their sum of effects operating alone.