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. 07, 1998
Filed:
Mar. 01, 1995
Applicant:
Inventors:
Joseph F Perret, Jr, Silver Spring, MD (US);
Donald A Ice, Ellicott City, MD (US);
William J Kautter, Columbia, MD (US);
Assignee:
GTCO Corporation, Columbia, MD (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G08C / ; G09G / ;
U.S. Cl.
CPC ...
178 18 ; 178 19 ; 178 87 ; 345173 ; 345175 ; 345176 ;
Abstract
An illumination apparatus for a digitizer tablet includes a support structure and a solid sheet optical light guide supported by the support structure and having first and second opposing surfaces and a plurality of edges. Light sources are carried by the support structure and positioned to direct light into light-receiving edges of the light guide. Reflecting structure is disposed adjacent the first surface of the light guide. A predetermined pattern is disposed on the first surface of the light guide structured and arranged in accordance with distance from the light sources.