Ultrasonic sensors are classified into transmitter and receiver according to the operating theory
When alternating current signals are input into the transmitter, the oscillator made up of piezoelectric ceramic slice and sheet metal makes resonances and releases ultrasonic waves through the cone-shaped radiant plate
When the ultrasonic gets to the receiver via the transmit of air, it is collected by the cone-shaped plate and makes its vibrations resonate
Corresponding alternating current signals are produced because of piezoelectric effects
Various kinds of control applications may be realized
With these features, ultrasonic sensors are widely used in products such as toys, remote controls, distance measurement, automatic doors and burglar alarms
