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:
Dec. 22, 1992
Filed:
Apr. 15, 1992
Applicant:
Inventor:
Alexander M Purcell, Guilford, CT (US);
Assignee:
Summagraphics Corporation, Seymour, CT (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02F / ;
U.S. Cl.
CPC ...
359 85 ; 359 36 ;
Abstract
A digitizer system comprises a source of a light for producing an image, a shutter, and a transparent or translucent digitizer tablet. The source is positioned to direct the image to the tablet via the shutter. The shutter comprises a liquid crystal layer and transparent planar conductors on opposite surfaces of the layer. The system further comprises a source of an adjustable voltage connected between the planar conductors for adjusting the transmissivity of the shutters.