Precision ultrasonic wave measurements with simple equipment

Abstract

We describe the design and construction of a relatively simple, inexpensive laser interferometer system for accurate measurements of ultrasonic surface displacement waveforms in reasonably friendly environments. We show how analysis of a single waveform can provide both the calibration constant required for absolute measurements and an estimate of the uncertainty of these measurements. We demonstrate the performance of this interferometer by measuring ultrasonic waveforms generated by a novel conical-element ultrasonic transducer.