Acoustic Sensors

Abstract

Basic concepts of transducers for sound and vibration are reviewed in this article. Discussions on the frequency and magnitude range of applications of the transducers are presented, followed by introductions of commonly used acoustic sensors and measurement methods such as microphones, ultrasonic transducers and laser Doppler velocimetry. The frequency range spreads from 10 Hz to 10 GHz, while the sound pressure from 10 μPa to 1 MPa. This article presents well-established conventional technologies as well as novel methods for measuring sound/vibration and new applications of the acoustic sensor devices. Various kinds of signal processing technique developed for detection and localization of sound/vibration source, and noise suppression are out of the scope of this review paper. Sensor devices utilizing sound and vibration are not included in this review.