Proximity sensor breakthrough: Detecting big targets increases capacitance, small targets no change.
A study looked at how a capacitive sensor detects objects by measuring changes in capacitance between its electrodes. The researchers found that when the sensor detects a target, the self-capacitance increases while the mutual capacitance decreases. For big targets, the overall capacitance between the electrodes slightly decreases, but for small targets, it remains the same.