The ultrasonic cutter is composed of a “transducer” that generates vibration and an “oscillator” that drives the transducer. A piezoelectric element is used for the transducer. When voltage is applied, the piezoelectric element displaces the transducer by a few micrometers. Periodically applying voltage generates vibration. Each object has its special frequency, by which the object is stable and easy to vibrate. By adding an external force that corresponds to that special frequency, a small force can obtain a large vibration. This phenomenon is called resonance.

In the ultrasonic cutter, the piezoelectric element generates a force that resonates the whole body, from the transducer to the blade tip, generating a large vibration at the tip. The oscillator periodically generates voltage to resonate and drive the transducer. Using a component of the ultrasonic cutter called the horn to wring the cross-sectional area, from the piezoelectric element to the blade tip, can obtain a larger vibration.