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. 27, 1987
Filed:
Oct. 18, 1984
Terry G Sherbeck, Hillsboro, OR (US);
Tektronix, Inc., Beaverton, OR (US);
Abstract
A touch panel input apparatus including two arrays of light detectors placed on the opposite sides of the display device screen and four light sources, each of which is placed at a corner and at angle to illuminate at least the entire array of the light detectors on the opposite side. The light detectors are scanned in synchronization with the selection of the light beam sources. A controlling microprocessor has stored in its memory four sets of data, one for each light source, regarding ambient light condition and beam interrupt thresholds for the light detectors. By software, two equations representing a line are determined and solved to obtain a cross point which corresponds to X-Y position of the finger on the screen.