PatentDOI
Laser velocimetry detection of underwater sound
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TLDR
In this paper, an apparatus for determining the velocity of sound waves in a liquid medium having a plurality of gas bubbles is presented. But it is not suitable for the detection of the acoustic wave through the fluid medium.Abstract:
An apparatus for determining the velocity of sound waves which includes a liquid medium having a plurality of gas bubbles. In the liquid medium, a laser transmits a light pulse to interact with the bubbles excited by the sound wave. Backscattered light from the interaction of the light pulse is received. A processor is then responsive to the detector to provide detection of the acoustic wave through the fluid medium.read more
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References
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Fiber optic sound velocity profiler
TL;DR: In this article, a steerable array of transducers sends a pulse of sound in the direction of the optical cable while broadband pulses of light are directed down the optical fiber, selectively reflected back according to the spacing between the Bragg gratings.
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Laser hydrophone and virtual array of laser hydrophones
TL;DR: In this paper, a laser beam is focused upon a small "focal" volume of water in which natural light scattering matter is suspended and which matter vibrates in synchronism with any sonic waves present.
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Dual beam doppler shift hydrophone
TL;DR: In this paper, a dual beam hydrophone with a reference laser beam and a signal laser m are modulated simultaneosuly by the movement of reflecting surfaces responding to pressure variatrions due to an impinging acoustic wave.
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TL;DR: In this paper, an apparatus and method for determining the velocity of sound propagation of a fluid as a function of position in the fluid along an axis is presented, where a wave of acoustic energy is transmitted along the axis to produce a disturbance, which moves in the medium at the speed of sound.
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