Shock-wave measurement using a calibrated interferometric fiber-tip sensor

The results of shock-wave measurements using a calibrated fiber-tip sensor based on a Michelson interferometer are presented. A transfer function, obtained by an independent experiment that describes the properties of the sensor system, was used to correct the measured shock-wave data in the Fourier frequency domain. The phase of the transfer function was determined from its amplitude by a fitting procedure using minimum-phase terms. As an example of application, the acoustic output field of an electromagnetic lithotriptor was investigated, and the shock-wave source was reliably characterized. The measured data provide a basis for estimating the hazard to which a patient is exposed during shock-wave treatment and for optimizing a lithotriptor system to produce a sharply localized and effective acoustic field.