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. 03, 2002
Filed:
Jul. 14, 2000
Judson G. McDonnell, Farmington Hills, MI (US);
James G. Stanley, Novi, MI (US);
Automotive Systems Laboratory, Inc., Farmington Hills, MI (US);
Abstract
A sense electrode ( ) is driven by a first oscillatory signal ( ) and at least one control electrode ( ) is driven by a second oscillatory signal ( ). In first ( ) and second ( ) states ( ), the second oscillatory signal ( ) respectively has a first and second phase with respect to the first oscillatory signal ( ). The proximity of an electric-field-influencing media ( ) to the proximity sensor ( ) is responsive to the difference of third ( ) and fourth ( ) signals that are respectively measured when the second oscillatory signal ( ) is in respective first ( ) and second ( ) states. The proximity sensor ( ) is calibrated with a known capacitance operatively coupled to the sense electrode ( ) with a plurality of switches (S , S ) adapted so that the switches (S , S ) have a relatively small effect on the capacitance of the sense electrode ( ).