Patent ID: 6443900
Filing Date: 2002-09-03
Classification: B06B,G01S,G10K

Abstract:
An ultrasonic transducer system for harmonic imaging, comprising:an ultrasonic transducer comprising a transmitting ultrasonic vibrator for transmitting a fundamental ultrasound having a center frequency f0, and a receiving ultrasonic vibrator for receiving a harmonic signal having a center frequency nf0 (n is an integer of 2 or more); and control means for controlling the ultrasonic transducer, wherein said transmitting ultrasonic vibrator comprises a transmitting piezoelectric resonator, said transmitting piezoelectric resonator comprises a pair of electrodes, said receiving ultrasonic vibrator comprises a receiving piezoelectric resonator, said receiving resonator comprises a pair of electrodes, the transmitting piezoelectric resonator and the receiving piezoelectric resonator are superposed and disposed in layers, and said control means supplies a drive signal to the transmitting piezoelectric resonator only for a time t1, holds a state between electrodes of the receiving piezoelectric resonator in a low resistance state including a short circuit for a predetermined time t2 (>t1) after the drive signal is supplied, and holds the state between the electrodes of the transmitting piezoelectric resonator in a high resistance state including an open circuit after an elapse of the predetermined time t2, until the next drive signal is supplied to the transmitting piezoelectric resonator.