Abstract
A method and an apparatus for determining the dynamic response of a microstructure by using a pulsed broad bandwidth ultrasonic transducer as a bulk acoustic wave hammer are disclosed. A piezocomposite ultrasonic transducer device formed of a piezoelectric material and a polymer material around said piezoelectric ceramic material is used to provide a pulsed bulk acoustic wave having a bandwidth of at least 20% to excite a microstructure. The microstructure is attached onto the transducer, and the pulsed bulk acoustic wave generated through the transducer in response to a pulse voltage excites the microstructure to vibrate. Meanwhile, the dynamic response of the microstructure can be monitored by a laser Doppler vibrometer, and shown by an oscilloscope.