Title :
Measurement of shock waves in the focus of a lithotripter
Author :
Granz, B. ; Holzapfel, R. ; Köhler, G.
Author_Institution :
Siemens AG, Erlangen, West Germany
Abstract :
For the measurement of ultrasonic shock waves with amplitudes near 40 MPa, two different hydrophones were constructed. The first is a high-bandwidth PVDF membrane hydrophone with a capacitively coupled signal. The second is a small acousto-optic fiber hydrophone which measures the shock-wave-induced variation of the refractive index of a liquid at the front end of the fiber. The properties of the hydrophones are compared. The first, with a sensitivity of 6 mV/MPa, demonstrates high durability and a 20-MHz bandwidth. The second has equally good characteristics and additionally measures the creation and the time dependence of cavitation bubbles in the liquid
Keywords :
biomedical ultrasonics; hydrophones; radiation therapy; shock waves; ultrasonic measurement; 20 MHz; 40 MPa; acousto-optic fiber hydrophone; capacitively coupled signal; cavitation bubbles; high-bandwidth PVDF membrane hydrophone; liquid refractive index variation; lithotripter focus; shock-wave-induced variation; ultrasonic shock waves measurement; Bandwidth; Biomembranes; Dielectric liquids; Electrodes; Fiber optics; Lithotripsy; Refractive index; Shock waves; Sonar equipment; Ultrasonic variables measurement;
Conference_Titel :
Ultrasonics Symposium, 1989. Proceedings., IEEE 1989
Conference_Location :
Montreal, Que.
DOI :
10.1109/ULTSYM.1989.67137
