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:
Sep. 06, 1994
Filed:
Apr. 29, 1991
Waldo L Landmeier, Phoenix, AZ (US);
CalComp, Inc., Anaheim, CA (US);
Abstract
In order to determine without ambiguity the grid sections on which the pointer is located in a cordless electromagnetic digitizer having x and y locating grids, a third, 'phase' grid has conductors that form elongated, narrow open loops, spaced so that each location on the work surface is enclosed by loops formed by a minority of the phase grid conductors. Any phase grid conductor with sufficient induced voltage can serve as a phase reference to determine the relative phases of the signals induced in all of the phase grid conductors. A phase grid conductor determined to have the relative phase of the minority can then serve as phase reference to identify the locating grid section unambiguously, and digitize the pointer location.