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. 01, 2013
Filed:
Oct. 03, 2011
Osamu Yoshikawa, Tokyo, JP;
Osamu Yoshikawa, Tokyo, JP;
SMK Corporation, Tokyo, JP;
Abstract
Changes of the stray capacitances of a large number of sensing electrodes can be detected simultaneously. Further, even if a stray capacitance changes slightly, an input operation to a sensing electrode can be detected based on elapsed time until the electric potential of the sensing electrode becomes the same as a threshold potential. The stray capacitance of a sensing electrode and a resistor of the sensing electrode form a CR time constant circuit. Charge or discharge of the stray capacitance of the sensing electrode is controlled while a rest time in a predetermined time ratio is set. A stray capacitance that slightly increases in response to an input operation made near a sensing electrode can be detected by detecting the stray capacitance in extended elapsed time until the electric potential of the sensing electrode becomes the same as the threshold potential.