Optical probing of the mechanical impulse response of a transducer

Abstract
The mechanical impulse response of a piezoelectric transducer has been plotted by using an optical interferometric heterodyne probe. The sensitivity of this Mach–Zehnder type probe is better than 10−4 Å/(Hz)1/2. Transient displacements of a few angstroms have been detected in a single sweep with a 20-MHz bandwidth.