【摘要】 为了获得物体内部清晰的三维图像,提高激光扫描声学显微镜的分辨能力,在激光扫描声学显微镜原理的基础上,阐述了层析扫描声学显微镜的结构和工作方式。结合层析技术并且根据超声波在介质中的传播规律介绍了三种层析算法:频域内的插值算法;往返传播算法;滤波反向传播算法。最后通过理论和实验比较,结果表明:往返传播算法通过对滤波函数进行改进,在有限孔径的前提下,应用于层析扫描声学显微镜时比其它两种算法可以获得更好的重建图像效果。更多还原

【Abstract】 The operation principle and structure of scanning tomographic acoustic microscope(STAM) are explained based on laser scanning acoustic microscope for resolution improvement.Three tomographic algorithms are described on the basis of ultrasound propagation in a medium.These are interpolation algorithm in the frequency domain,back-and-forth propagation algorithm,and the filtered back-propagation algorithm.By comparison of the three algorithms theoretically and experimentally,it is shown that back-and-forth propagation algorithm can be improved with a filter function,under the condition of a finite aperture,and better reconstruction than the other two al-gorithms may be obtained更多还原