| 摘要 |
PURPOSE:To obtain a probe which can transmit and receive ultrasonic waves in the same position simultaneously and to improve the time resolution without lowering the sensitivity, by setting the operating frequency of an organic piezoelectric material to a value in the range of 0.4-2.4 times as high as the operating frequency of an inorganic piezoelectric material. CONSTITUTION:In case that an ultrasonic signal is transmitted to an object 10 to be examined, a signal such as impulse having signal components of the frequency band of ultrasonic waves is applied across electrodes 11 and 12, and then, piezoelectric elements 2 and 3 generate the ultrasonic signal. This ultrasonic signal is transmitted to the side of the object 10 and the side of a packing material 4, and the ultrasonic signal transmitted to the side of the packing material 4 is absorbed and attenuated by the packing meterial 4. Meanwhile, the ultrasonic signal having different center frequencies transmitted to the side of the object 10 is reflected and scattered on the acoustic boundary face (fault) in the object 10 to be examined. When reflected and scattered ultrasonic waves are incident to a probe 1, an electric signal (receiving signal) is generated between electrodes where each piezoelectric material break is interposed, and this electric signal is supplied to a measurer, an analyzer, etc. |
