Hydrophones ultrasonic field measurements

Ide, M., Ohdaira, E. and Ohtsuka, M. (1980) Miniature hydrophones for the measurement of ultrasonic field. Proceedings of the Tenth International Congress on Acoustics, Sydney, Australia, 19 20 July 1980, paper F-7.1. 

Ide, M. and Ohdaira, E. (1981) Wide frequency range miniature hydrophone for the measurement of pulse ultrasonic field, Jpn. J. App. Phys., 20, 205. ... 

Piezoelectric polymer hydrophones have been proposed as probes (or mapping ultrasonic fields and determining acoustic field parameters in both water and biological media. Among the several PVDF hydrophones developed, the most widely used have been the original hoop membrane configuratioo (spot-poled membrane supported by means of a hoop) (40] and the needle-type probe (41]. While both can be used to assess ultrasonic field patterns in water, only the needle-type probe can be used for bioacoustic measurements, such as in vitro and in vivo evaluatkm of tissue properties. 

Harris, G.R. (1988) Hydrophone measurements in diagnostic ultrasound fields, IEEE Trans. Ultrason. Ferroelec. Freq. Contr., 35, 87 101. 

G. R Harris. E. F. Carome. and H. D. Dardy, An analysis of poised ultraaonic fields as measured by PVDF spot-poled membrane hydrophone. IEEE Trans. Soaks and Ultrasonics, SU-3[Pg.732]

Besides interest in low-frequency shock wave hydrophones, there have also been investigations of shock wave hydrophones for ultrasonic applications. Focused fields of ultrasonic pulses occurring in lithotripsy can be measured using ferroelectric polymer sensors. A Study in a water-filled tank has led to the development of a 2S-p,m PVDF hydrophone. The sensitivity of this sensor is 20 mV/MPa with a bandwidth of 20 MHz. More than 100,000 focused shock wave pulses of 20 MPa have been recorded successfully without a significant decrease in acoustic sensitivity [14],... 

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