Method and apparatus for studying vibrational modes of an electro-acoustic device

A method for studying vibrational modes of an electro-acoustic device comprising:

• driving the electro-acoustic device to produce at least one vibrational mode therein;
• collecting phase and amplitude data from the electro-acoustic device using optical interferometry by measuring the phase and amplitude data using an optical detector and homodyning an output signal from the optical detector and phase-detecting the homodyned output signal to determine the phase and amplitude data;
• and
• mapping the at least one vibrational mode based upon the collected phase and amplitude data.

An apparatus for mapping vibrational modes of an electro-acoustic device comprising:

• a signal source for driving the electroacoustic device to produce at least one vibrational mode therein;
• an optical interferometer for collecting phase and amplitude data from the electro-acoustic device;
• and
• a controller coupled to said signal source and said optical interferometer for controlling said signal source and mapping the at least one vibrational mode based upon the collected phase and amplitude data by processing the phase and amplitude data to provide an instantaneous three-dimensional view of the at least one vibrational mode and constructing a sequence of instantaneous three-dimensional views to form a motion picture of the at least one vibrational mode.