一、前言材料为蓝宝石的球面声透镜,是扫描声显微镜的核心元件。它利用一端面的凹球面把另一端面上换能器发射的平面波折射后,在其外部的耦合媒质中得到一个焦点,其原理如图1所示。为了避免声波衰减幅度过大,对声透镜体聚焦凹球面的球面半径有较严格的限制。如500MHz的声透镜,其球面半径 First, the foreword Sapphire spherical acoustic lens is the core component of the scanning acoustic microscope. It utilizes the concave spherical surface of one end to refract the plane wave emitted by the transducer on the other end surface and obtains a focal point in the coupling media outside thereof. The principle is shown in FIG. 1. In order to avoid excessive amplitude attenuation of acoustic waves, the spherical radius of the focused spherical concave surface of the acoustic lens has more strict restrictions. Such as 500MHz acoustic lens, the spherical radius