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:
May. 12, 1998
Filed:
May. 23, 1996
Yung-Ho Shih, Bellevue, WA (US);
Microsoft Corporation, Redmond, WA (US);
Abstract
A method for calibrating a touch panel display includes generating contact coordinates (x.sub.i, y.sub.i,i=1, . . . , N) indicative of N touch points of contact on the touch panel display, where N>3. The touch points can be selected at random on the touch panel, and are not constrained to specific, predefined locations. The contact coordinates (x.sub.i, y.sub.i) are related into screen coordinates (x.sub.i, y.sub.i,) according to the following mapping transformation: ##EQU1## This mapping transformation accounts for all possible two-dimensional transformations including transposition, rotation, and shearing. After N sets of digitizer and screen coordinates are found, values for the parameters a.sub.1, b.sub.1, c.sub.1, a.sub.2, b.sub.2, and c.sub.2 are derived. Preferably, the parameters are determined using an optimizing algorithm, such as a least square fitting algorithm. The parameters a.sub.1, b.sub.1, c.sub.1, a.sub.2, b.sub.2, and c.sub.2 are stored and thereafter used for all mapping transformations.