| 摘要 |
PURPOSE:To make the attenuation of an ultrasonic pulse waveform steep, to shorten the pulse width, and to improve resolution, by oscillating two piezoelectric oscillators, adhered together in such a way that their axes of polarization by a piezoelectric effect are in the same direction, in the opposite phases and thus suppressing the oscillation. CONSTITUTION:An ultrasonic probe is formed by forming electrode surfaces 24 and 25 on both outsides of an electrode surface 23 between piezoelectric oscillators 21 and 22, and is sticked. On the electrode surface 24, an acoustic matching layer 26 is formed and on the electrode surface 25, a damping layer 27 is formed. Driving pulses from a generator 31 are supplied to the electrode surfaces 23 and 24, and an oscillator 21 sends out ultrasonic pulses through the layer 26. The driving pulses are supplied to the control terminal of a switch circuit 34 through a timer circuit 37 to turn on the electrode surfaces 24 and 25. Therefore, an oscillator 22 starts oscillating in the opposite phase to the oscillator 21, and suppresses a composite oscillation voltage greatly to eliminate piezoelectric oscillation, namely, to damp it electrically. |
