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. 10, 2002
Filed:
Nov. 30, 1999
Gary T. Boyd, Woodbury, MN (US);
Richard A. Miller, Stillwater, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A cavity diffuses light received from a light source so as to produce a uniform light output. The cavity is formed from a unitary structure having one or more portions that diffusely reflect light within the cavity and another portion that transmits the uniform light output. The cavity is a unitary structure, formed from an optically diffusive material, that defines a diffusing cavity having an access aperture. A portion of the unitary structure defines diffusely reflective walls and another portion of the unitary structure defines a diffusely transmitting screen. A portion of the diffusely reflecting walls has a portion that has a thickness being greater than a thickness of the diffusely transmitting screen. The diffusely reflective walls reflect and mix light within the diffusing cavity. The diffusing cavity may be employed in an illuminated display device, having a light source and an imaging device which imposes an image on light received from the cavity.