Air-coupled ultrasound acoustic field measurements using laser Doppler vibrometers
WU Qiao;ZHOU Yuxuan;LIAN Guoxuan;WANG Xiaomin;State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences;University of Chinese Academy of Sciences;
An experimental research of acoustic field measurement is carried out aiming at the weakness aircoupled signal. Using the laser Doppler vibrometer, the variation of refractive index of the media along the laser path can be measured, which is caused by acoustic waves. The temporal acoustic pressure signals in air or solid media can thus be obtained. By measuring the radiated acoustic power, a direct assessment method of the sensitivity of single air-coupled transducer is given. Leaky Lamb wave of K9 glass plate in the air excited by air-couple transducers is given. The temporal acoustic pressure signals of the direct and reflective waves in the air, the leaky Lamb wave both in solid and air are observed. The experimental measurement of low amplitude acoustic waves in air or solid media is achieved, providing a direct procedure for the characterization and assessment of air-coupled transducers and the measurement of the acoustic field of air-coupled testing systems.