Study on the Effect of Target Conductor on the Capacitance between Proximity Capacitive Sensor Electrodes

Capacitive sensor detects its target through the change of capacitance between the electrodes. To two-electrode capacitive sensor, the changes of the self-capacitance, mutual capacitance and equivalent one are discussed respectively for detection of big and small target conductor. From the research, it can be concluded that when the proximity capacitive sensor detects target, the self-capacitance will increase, while the mutual capacitance will decrease. When big target is detected, the equivalent natural capacitance between electrodes will decrease slimly; when small conductor is detected, it will not change.