超声检测技术讲座　第一讲　超声检测的物理基础

Lecture One: the Physical basis of Ultrasonic Detection

简要介绍了波与振动的关系，超声波的分类，超声波的传播特性与声场特征量。同时介绍了超声波换能器（探头）及其等效电路。

This lecture simply introduces the relation between wave and vibration, the classification of ultrasonicwave, the trarsmission character of ultrasonicwave and the sonic field characteristic parameters. It also introduces ultrasonic transducer and its equivalent circuit.