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:
Oct. 06, 1992
Filed:
Jan. 30, 1991
David A Siefer, Orange, CT (US);
Alexander M Purcell, Wallingford, CT (US);
Summagraphics Corporation, Seymour, CT (US);
Abstract
A digitizer tablet is provided in which the working surface is illuminated by a light source which includes optical structure located over the grid or electrode array of the position determining structure of the digitizer to provide a surface-lit tablet, or beneath the grid or electrode array to provide a back-lit tablet. Preferably, a space is provided adjacent the working surface to reduce undesirable lighting effects. A fiber optics panel or an electroluminescent panel may be used as the optical structure placed above or beneath the grid to illuminate the working surface. The position determining structure and the optical structure may be integrated into a single unit to form a digitizer with an illuminated working surface, or the optical structure may be provided as a separate unit for use with a digitizer to provide an illuminated working surface for the digitizer.