Majority of people use ‘Transducer’ as an exchange of “sensor” and the reverse. But technically, we use ‘Transducer’ as word for collective used term form for both Sensors (which sense movements, electrical signals…) and Actuators. Actuators convert the eco into a pulse of electrical signal.大多数人使用换能器作为交换传感器，反之亦然。但从技术上讲，我们使用“换能器”作为传感器（感知运动、电信号……）和致动器的统称。执行器将生态信号转换成脉冲电信号。
The piezoelectric element is an essential part of the transducer to generate ultrasonic waves. On both sides of the piezoelectric element electrodes are affixed and a voltage is applied. The element then oscillates by repeatedly expanding and contracting, generating a sound wave. When the element is externally applied with vibration (or an ultrasonic wave) in turn, it generates a voltage.压电元件是产生超声波的换能器的重要组成部分。在压电元件的两侧贴上电极并施加电压。然后，该元件通过反复膨胀和收缩而振荡，产生声波。当元件在外部依次施加振动（或超声波）时，它会产生电压。
Among the several types of piezoelectric elements, piezoelectric ceramic (PZT: lead zirconatetitanate) is most commonly used because of its high conversion efficiency.在几种类型的压电元件中，压电陶瓷（PZT：锆钛酸铅）因其转换效率高而最常用。