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. 19, 2006
Filed:
Jul. 17, 2002
Cornelis Van Berkel, Hove, GB;
Cornelis van Berkel, Hove, GB;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
A combined passive and active object sensing system () employing electric field sensing is described. An electric field sensing transmission electrode () generates a first electric field () that induces a current in an electric field sensing reception electrode (). A passive object () is sensed from variation in this current. An active object () comprises a further electric field sensing transmission electrode () and generates a second electric field (). This may be generated by the active object () coupling with and applying a phase shift to the first electric field (). Alternatively the second electric field () may be generated at a different frequency to the first electric field (). Alternatively the second electric field () may be generated by the active object () coupling with an alternating magnetic field generated by a coil (). The second electric field () induces a current in the electric field sensing reception electrode () that varies with the position of the active object (). The separate currents are distinguished by virtue of their different phase or frequency.