Ultrasonic wave transducer system and ultrasonic wave transducer

An ultrasonic transducer for harmonic imaging, comprising:

• a transmitting ultrasonic vibrator including a transmitting piezoelectric resonator, for transmitting a fundamental ultrasound having a center frequency f0;
• and
• a receiving ultrasonic vibrator including a receiving piezoelectric resonator, for receiving a harmonic signal having a center frequency nf0 (n is an integer of 2 or more),
• wherein said transmitting piezoelectric resonator has an annular band shape, said receiving piezoelectric resonator has a disc shape, said receiving piezoelectric resonator is disposed inside said transmitting piezoelectric resonator, and said transmitting piezoelectric resonator and said receiving piezoelectric resonator have different thicknessess.

An ultrasonic transducer for harmonic imaging, comprising:

• a plurality of transmitting ultrasonic vibrators for transmitting a fundamental ultrasound having a center frequency f0, each of said transmitting ultrasonic vibrators comprises a transmitting piezoelectric resonator and an acoustic lens disposed in front of the transmitting piezoelectric resonator, said transmitting ultrasonic vibrator further comprises a damping layer disposed on the back surface of the transmitting piezoelectric resonator;
• and
• a plurality of receiving ultrasonic vibrators for receiving a harmonic signal having a center frequency nf0 (n is an integer of 2 or more) , each of said receiving ultrasonic vibrators comprises a receiving piezoelectric resonator and an acoustic lens disposed in front of the receiving piezoelectric resonator, the acoustic lens of the receiving ultrasonic vibrator having a curvature radius smaller than a curvature radius of the acoustic lens of the transmitting ultrasonic vibrator, said receiving ultrasonic vibrator further comprises a damping layer disposed on the back surface of the receiving piezoelectric resonator, where the damping layers have different thickness values,
• wherein said transmitting ultrasonic vibrators and said receiving ultrasonic vibrators are alternately disposed in radial form.

An ultrasonic transducer for harmonic imaging, comprising:

• a transmitting ultrasonic vibrator for transmitting a fundamental ultrasound having a center frequency f0 in response to input of an electric signal;
• and
• a receiving ultrasonic vibrator for receiving a harmonic signal having a center frequency nf0 (n is an integer of 2 or more) generated in an object by the fundamental ultrasound,
• wherein said transmitting ultrasonic vibrator comprises a transmitting piezoelectric resonator, said receiving ultrasonic vibrator comprises a receiving piezoelectric resonator, the transmitting piezoelectric resonator and the receiving piezoelectric resonator are disposed on the same plane, and the transmitting piezoelectric resonator and the receiving piezoelectric resonator satisfy (g33r·Vr·Qr)/(g33t·Vt·Qt)≧n·(1+R), in which g33t and Vt denote a voltage output coefficient and a sound velocity of the transmitting piezoelectric resonator, g33r and Vr denote a voltage output coefficient and a sound velocity of the receiving piezoelectric resonator, n denotes a harmonic order, R denotes an opening area ratio (an opening area of the receiving piezoelectric resonator/an opening area of the transmitting piezoelectric resonator), and Qt and Qr denote resonance sharpness of the transmitting ultrasonic vibrator and the receiving ultrasonic vibrator, respectively.

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 in response to input of an electric signal and a receiving ultrasonic vibrator for receiving a harmonic signal having a center frequency nf0 (n is an integer of 2 or more) generated in an object by the fundamental ultrasound, said transmitting ultrasonic vibrator comprising a transmitting piezoelectric resonator, said receiving ultrasonic vibrator comprising a receiving piezoelectric resonator, said transmitting piezoelectric resonator and said receiving piezoelectric resonator being disposed on the same plane, said transmitting piezoelectric resonator and said receiving piezoelectric resonator satisfying (g33r·Vr·Qr)/(g33t·Vt·Qt)≧n·(1+R), in which g33t and Vt denote a voltage output coefficient and a sound velocity of the transmitting piezoelectric resonator, g33r and Vr denote a voltage output coefficient and a sound velocity of the receiving piezoelectric resonator, n denotes a harmonic order, R denotes an opening area ratio (an opening area of the receiving piezoelectric resonator/an opening area of the transmitting piezoelectric resonator), and Qt and Qr denote resonance sharpness of the transmitting ultrasonic vibrator and the receiving ultrasonic vibrator, respectively;
• and
• drive control means for driving/controlling the ultrasonic transducer,
• wherein said drive control means generates an ultrasound in which at least a component of 2f0 is inhibited in the transmitting ultrasonic vibrator.