【摘要】 本文提出了利用阴影法观察声光晶体中的超声驻波图像并利用该图像测量超声波在晶体中传播速度的方法,并将其与传统的声光衍射方法进行对比,分析了两者各自的优缺点。本方法可以直接观察到晶体内部由超声驻波造成的介质密度周期性分布图像。利用该方法测得的超声波波速与利用衍射方法测得的波速精确度相当,但这种方法使用的仪器更简单,并有利于更直观地理解超声驻波在声光晶体中的传播,同时也有助于加强实验者对阴影法的认识。更多还原

【Abstract】 The observation of ultrasonic standing wave in acousto-optic crystal with the method of shadowgraph,which leads to a new method in acoustic velocity measuring,is discussed in this paper.Besides,this new method is compared with the traditional way of measuring which is based on acousto-optic diffraction,and the pros and cons are analyzed in this paper.With this new method,the periodical distribution caused by the ultrasonic standing wave can be straightly observed in the crystal.The precision of this new method can match the traditional one based on diffraction phenomenon,but it takes simple devices and helps to have a more intuitive understanding of the spreading of ultrasonic standing wave in acousto-optic crystal,as well as the shadowgraph system.更多还原