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:
May. 17, 2005
Filed:
Feb. 14, 2001
John C. Wright, High Wycombe, GB;
Andrew M. Hicks, Reading, GB;
Bruno Mueller, Duesseldorf, GB;
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A light guide () comprises a housing () defining a light-guiding optical cavity having first and second opposed major faces (), and a light source () arranged to direct light into the cavity from one end, to be guided between the major faces. The first major face () comprises a window through which light can be emitted from the optical cavity to be used, for example, for illuminating a graphic display. To improve the light distribution across that first major face (), the second major face () comprises a sheet material () having a specularly-reflecting surface () that faces into the optical cavity and has diffusely-reflecting light-extraction elements () applied thereto in a predetermined configuration for causing light to be emitted from the optical cavity through the said window.