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. 09, 2002
Filed:
Mar. 31, 2000
Applicant:
Inventors:
Neal T. Strand, Woodbury, MN (US);
David G. Freier, St. Paul, MN (US);
Ellen O. Aeling, St. Paul, MN (US);
Assignee:
3M Innovative Properties Company, St. Paul, MN (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F21V 1/114 ;
U.S. Cl.
CPC ...
F21V 1/114 ;
Abstract
An illuminated sign system provides uniform illumination over the lamp face by using partially transmissive lamp masks located between the lamps and the sign face. The sign face itself also diffusely reflects at least a majority of light incident on its second surface back towards the interior of the sign. The lamp spacing ratio in the illuminated signs can be increased, e.g., to a ratio of 3:1 or more, and, possibly, to a ratio of 4:1 or more.