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. 17, 1990
Filed:
Mar. 14, 1989
Dale R Flowers, Atlanta, GA (US);
Kevin P Goffinet, Cary, NC (US);
Anthony W Miles, Raleigh, NC (US);
John T Rowe, Jr, Raleigh, NC (US);
Kevin H Vorhees, Raleigh, NC (US);
IBM Corporation, Armonk, NY (US);
Abstract
A touch sensing display apparatus having improved electrical signal processing is described. A plurality of signal threshold comparison levels are employed by the electronic signal calculating and processing unit to identify actual touch signals and to exclude extraneous vibration and offset signal components. Static thresholds of comparison are utilized at lower signal levels and a dynamic, signal tracking threshold is utilized at higher signal levels. The apparatus is particularly effective for use in designs employing a suspended CRT display or other display device in which the screen of the display device is directly touched by a user to record selections of information presented or to input graphical or handwritten information.