近几年迅速发展起来的激光布里渊散射(Brillouin scattering)是研究固体、液体、气体中低频元激发的有力工具。在它的众多应用中,声速及其各向异性的测量是最基本的和最重要的。 我们应用最近组建起来的布里渊散射谱仪测量了单晶LiNbO_3在几个方向上纵声波、横声波的声速,并与文献值进行了对比。初步实验表明,目前声速测量的精度为±1%,结果可靠,方法简便快速。也表明该布里渊散射谱仪是可靠的,可用的。 In recent years, the rapid development of laser Brillouin scattering (Brillouin scattering) is to study solid, liquid, gas, low-frequency element excitation powerful tool. In many of its applications, the measurement of sound velocity and its anisotropy is the most basic and important. We have used the newly-built Brillouin scattering spectrometer to measure the sound velocity of longitudinal and transverse acoustic waves in single direction LiNbO_3 in several directions, and compared with the literatures. Preliminary experiments show that the current sound velocity measurement accuracy of ± 1%, the result is reliable, the method is simple and fast. It also shows that the Brillouin scattering spectrometer is reliable and usable.