Phase changes of ultrasonic bulk waves through focusing measured using a noncontact ultrasonic method

摘要

Focusing an ultrasonic surface or bulk wave to a point can maximize the amount of ultrasonic energy at a point and increase the sensitivity of a measurement. Using a noncontact, ultrasonic method we focus an ultrasonic bulk wave pulse in a sample, using the surface profile of the sample itself to focus the wave. Experiments and modeling confirm that the wave pulse undergoes a phase shift on passing through the focal point.