07205777 is referenced by 59 patents and cites 10 patents.

A capacitive proximity switch for detecting the change in the capacitance relative to a setpoint capacitance by the approach or retreat of an object in the sensitive area of a proximity switch, especially for use in the door handle of a motor vehicle, provides reliable error detection and error suppression at a fundamentally high sensitivity of the capacitive proximity switch by utilizing an evaluation unit that evaluates a measured value of the change in capacitance over time and depending on the time behavior of the measured value activates changes the operating threshold from a first threshold (which can be caused by a false object coming into or out of the sensitive area of the proximity switch) to a higher second threshold which can be reached only at a relatively greater change in capacitance caused by a target object coming into or out of the sensitive area of the proximity switch.

Title
Capacitive proximity switch
Application Number
10/913498
Publication Number
7205777 (B2)
Application Date
August 9, 2004
Publication Date
April 17, 2007
Inventor
Gianni Uselli
Velbert
DE
Martin Witte
Ahaus
DE
Bernd Steegmann
Heiligenhaus
DE
Heidrun Richter
Wertingen
DE
Gerhard Heilig
Waldburg
DE
Joerg Schulz
Lustenau
AT
Agent
David S Safran
Assignee
Huf Huelsbeck & Fuerst & Co KG
DE
i f m electronic
DE
IPC
G08B 21/00
B60R 25/10
B60L 3/00
G01R 27/26
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