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:
Jul. 23, 2013
Filed:
Apr. 16, 2009
Reinhard Unterreitmayer, Gauting, DE;
Stefan Donat, Gilching, DE;
Reinhard Unterreitmayer, Gauting, DE;
Stefan Donat, Gilching, DE;
Ident Technology AG, Wessling, DE;
Abstract
An electrical hand-held device with proximity detection can be placed on a surface and has at least one transmission electrode, at least one reception electrode, and at least one compensation electrode between the transmission and reception electrodes. The transmission and compensation electrodes can be supplied with electric switching signals of predetermined frequency and amplitude. The electric switching signal at the compensation electrode is phase-delayed with respect to the electric signal at the transmission electrode. Alternating electric fields radiated at the transmission and compensation electrodes generate in the reception electrode a current that is representative of an approach of a hand to the hand-held device. The transmission and reception electrodes are arranged such that the impedance between the transmission and the reception electrodes exceeds a predetermined value suitable to keep the current generated in the reception electrode under a predetermined value.