A method of estimating ultrasound fields at full power using infrared and hydrophone system

The acoustic characterization of ultrasound fields is not only important for the safety and efficiency of clinical treatment, but also for therapy planning. In this paper, a method to estimating the ultrasound fields at full power using hydrophone and uncooled infrared system was developed. The method includes four steps. The amplitude absorption coefficient of the medium can be measured through the first two steps. Through the second and third steps, we can estimate the ratio of absorber´s heat capacity per unit volume to absorber´s ultrasonic amplitude absorption coefficient. This ratio will be used to in step four, in order to estimate the intensity of HIFU at high driving voltage. This method made it is possible to determine the intensity of HIFU driving with high voltage, and there were no need to know the thermal and acoustic parameters of acoustic absorber.