P1B-4 Characterization of a HIFU Field at High Intensity

Accurate quantification of HIFU fields has been hampered by the inability of traditional hydrophones to survive the high pressures encountered. We present a set of data at high intensities taken with a hydrophone capable of surviving this environment, which included 5 MPa maximum rarefactional pressure, pulse-average-spatial-peak intensity of 3760 W/cm², and a total power of 101 Watts. Comparisons are made to predictions of a KZK model and an independent measurement of total power via radiation force balance, and are found to be favorable. Beamplots show more than 50% reduction in the -3 dB beam area measured at low power, in agreement with KZK predictions.