Optical imaging of transient acoustic fields generated bypiezocomposite transducers

摘要

Transient surface displacements of 1-3 piezocomposite transducersnare measured and their correlative effects on the diffraction of thentransmitted pulses are studied. The displacements of the surface of an210 Μm pitch piezocomposite are probed with a heterodyne, opticalninterferometer. An animate sequence is then built from the storedntransient displacements so that each frame shows the instantaneous statenof the surface of the piezocomposite. Such an animation proves to be anpowerful analysing tool which provides a real insight into thenpiezocomposite's impulse behavior. Finally, the ultrasonic fieldntransmitted in water and measured by the same optical probe is comparednwith simulations based on the diffraction impulse theory. The results ofnthat comparison clearly show that, as far as diffraction is concerned, anpiezocomposite transducer behaves like a homogeneous material