In electrical engineering, capacitive sensing (sometimes capacitance sensing) is a technology, based on capacitive coupling, that can detect and measure anything that is conductive or has a dielectric different from air.

 

Capacitive proximity sensors are non-contact devices that can detect the presence or absence of virtually any object regardless of material.  They utilize the electrical property of capacitance and the change of capacitance based on a change in the electrical field around the active face of the sensor.

 

Capacitive sensing technology is often used in other sensing technologies such as: