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Capaciflector cameraA capacitive type proximity sensor having improved range and sensitivity between a surface and an intruding object in the vicinity of the surface having a voltage source, a number of outer electrical conductors on the surface with each forming one electrode of a number of sensor capacitors, the other electrode for each sensor capacitor being the object. The outer conductors are made from thin sheets of conductive material covered with insulation. An intermediate electrical conductor is located between the outer conductors and the surface and is of a size larger than the outer conductors to act as a shield for reducing the parasitic capacitance between the outer conductors and the surface. The intermediate conductor is also made from a thin sheet of conductive material covered with insulation. The outer conductors and the intermediate conductor are attached to the surface with no gap between the insulation on the conductors and no gap between the surface and the insulation on intermediate conductor, the outer conductors and the intermediate conductor conjoining with each other and with the surface, with the surface acting as a ground plane. A current-measuring voltage follower circuit is connected to the voltage source for coupling in phase and amplitude the instantaneous voltage at the voltage source to the outer electrical conductors and the intermediate electrical conductor. This circuit is responsive to the change in capacitance of the sensor capacitors and generates a number of output signals.
Document ID
20080004799
Acquisition Source
Headquarters
Document Type
Other - Patent
Authors
Vranish, John M.
Date Acquired
August 24, 2013
Publication Date
December 13, 1994
Subject Category
Electronics And Electrical Engineering
Report/Patent Number
Patent Number: US-PATENT-5,373,245
Patent Application Number: US-PATENT-APPL-SN-090230
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-PATENT-5,373,245
Patent Application
US-PATENT-APPL-SN-090230
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