Ultrasonic sensor and method for manufacturing it

摘要

To measure the sound pressure amplitude in the area of the focus of a focussed ultrasonic shockwave, ultrasonic sensors are needed which withstand the mechanical stresses occurring in the area of the focus and have a largely angle-independent receiving sensitivity. According to the invention, the ultrasonic sensor contains a metallic wire (2), which is mounted in a holding device (10) and which is provided with a piezoelectric polymer layer (4) over some of its length and, at the same time, is used as inner electrode. As a counter electrode, an electrode (6) is provided which is arranged spatially separately from the polymer layer (4) on the holding device (10). Focus monitoring in lithotripters. <IMAGE>