A measurement system for continuous wave ultrasound fields.

A measurement system for evaluating ultrasound fields is presented. The system utilizes a PVDF hydrophone and a mechanical scanning device. For continuous wave (CW) ultrasound, a high sensitivity is achieved by using a narrow band technique. The high sensitivity is demonstrated in a recording of the beam profile from an air transducer. Recordings from fetal Doppler equipment shows that, due to interference between the multiple transmitters, a high spatial resolution is needed in the field measurements in order to obtain correct values for peak intensities.