Title :
Optical heterodyne detection of pulsed ultrasonic pressures
Author :
Jia, X. ; Quentin, G. ; Lassoued, M.
Author_Institution :
Paris Univ., France
Abstract :
An optical heterodyne interferometer was used for measuring short ultrasonic pulses in fluids. The optical phase shift of the probe beam, proportional to the acoustic pressure integrated along the light path, was demodulated quantitatively by electronic processing. The detection sensitivities of 10/sup -3/ (Pa/ square root Hz) in water and 10/sup -4/ (Pa/ square root Hz) in air were deduced. The experimental results obtained in water as well as in air show that this optical heterodyne technique offers a very sensitive way of measuring ultrasonic pressures in the low megahertz range even for very low pressures.<>
Keywords :
air; light interferometry; measurement by laser beam; pressure measurement; ultrasonic measurement; water; H/sub 2/O; acoustic pressure along light path; air; detection sensitivities; electronic processing; experimental results; low megahertz range; optical heterodyne interferometer; optical heterodyne technique; optical phase shift; probe beam; pulsed ultrasonic pressures; short ultrasonic pulses measurement; ultrasonic pulses in fluids; water; Acoustic pulses; Acoustic signal detection; Optical detectors; Optical interferometry; Optical mixing; Optical pulses; Optical sensors; Phase shifting interferometry; Pulse measurements; Ultrasonic variables measurement;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
