Focusing piezoelectric ultrasonic medical diagnostic system

摘要

There is disclosed an ultrasonic piezoelectric transducer consisting of two separate transducer elements bonded together. The individual elements may be similar or different in size, thickness, and/or material. The material which bonds the two elements together may serve as one electrode, and two other electrodes coat the outer surfaces of the two individual elements. By switching the electrodes which are connected to the transmit and receive circuits of an ultrasonic medical scanning apparatus, the single transducer may be used for imaging with high resolution at one frequency, and for pulse Doppler velocity measurements at a different frequency. The two elements may be driven individually or in combination, in order to achieve different operating frequencies and focusings.