Exposimetry of unfocused pulsed ultrasound

摘要

Therapeutic applications of unfocused pulsed ultrasound havenrecently been identified and require specialized exposimetry. Spatialndistributions of pressure and several measures of intensity arenpresented for an unfocused pulsed ultrasound field produced by a PZT-4ntransducer with diameter 3.8 cm and center frequency 2 MHz.nDistributions of pressure Itp and Im werenadequately uniform over a 4-cm2 area in a transverse plane atnan axial distance of 7 cm, but not so for Ita and Ipan, which both exhibited off-axis asymmetric maxima