Transducer for medical imaging which transmits a first harmonic and predominantly receives second harmonics

摘要

The piezoelectric transducer (10) is active at two different frequencies. A piezoelectric arrangement has a series of piezoelectric layers (12) extending from a first to a second piezoelectric surface and electrodes (14B) between adjacent layers. First and second electrodes (14A,14C) contact the first and second surfaces and apply a voltage difference across the piezoelectric arrangement, which is connected to a transmission/reception line. A first changeover switch switches between the two frequencies.