声光效应实验研究

介绍声光效应的最新理论进展。采用光栅假设，对各向同性介质中的声光效应作了简要讨论，导出了第m级衍射光的衍射效率公式。研究和介绍一种新的声光效应实验装置。在实验中，应用线阵CCD光强分布测量仪等，通过改变超声波的频率和功率，分别实现了对激光束方向的控制和强度的调制；定量给出了声光偏转量的关系曲线和声光调制测量的关系曲线。实验表明，在布喇格衍射下，通过固定超声波功率，测量衍射光相对于零级衍射光的相对光强与超声波频率的关系曲线，不仅可以计算声速，还可以确定声光器件的带宽和中心频率。

Experimental investigation of acoustooptic effect

The new theoretic development on acoustooptic interaction is introduced.Adopting the tentation of raster,the acoustooptic interaction in isotropic medium is discussed,and the formula of diffractive efficiency for the diffractive beam is deduced.A new experiment equipment on acoustooptic interaction is developed.By means of a linear array CCD light-intensity distribution measuring system,via the variation of the frequency and the power of ultrasonic wave,the direction control and the intensity modulation for the laser beam can be carried out.The relation curve between acoustooptic deflexion and modulation measurement is given.The experimental result shows that as the power of ultrasonic wave is fixed,and the relation curve of the diffractive light-intensity relative to zero-order diffractive light and ultrasonic frequency is measured,not only the sound velocity can be calculated,but also the bandwidth and the centric frequency of an acoustooptic element can be confirmed under Bragg diffraction.