Patent ID: 9733290
Date: 2017-08-15
CPC Classifications: G01R,H03K

Claim:
1. Capacitive sensor device with an electrode system, comprising: a first transmitting electrode and a first reception electrode, wherein the first transmitting electrode is capacitively coupled with the first reception electrode, and a second transmitting electrode and a second reception electrode, wherein the second transmitting electrode is capacitively coupled with the second reception electrode, a signal generator for feeding the first transmitting electrode with a first electric alternating signal and the second transmitting electrode with a second electric alternating signal wherein the first and second reception electrode receive signals from the first and second transmitting electrodes, respectively and wherein the first reception electrode provides a respective first electric value and the second reception electrode provides a respective second electric value, and a signal processing device, which is coupled with the first reception electrode and with the second reception electrode, and wherein the signal processing device forms a first measurement variable from the difference between the first electric value and the second electric value and wherein the signal processing device further forms a second measurement variable from the sum of the first electric value and the second electric value, wherein the first electric variable substantially reduces the influence of interfering electric fields and the second electric variable is non-zero in response to an object to be detected approaching the first and second transmitting electrodes unevenly, and wherein the AC voltage component of the first electric alternating signal is inverse to the AC voltage component of the second electric alternating signal.