一、引言 一个声信号都能同时提供振幅和相位这两个信息。在许多场合发现,相位检测往往比幅度检测更有效。例如,利用光声信号的相位信息来进行材料表面的无损检测、光声成象[1]、测定材料的相变[2]、测定材料的热导率[3]等,比利用光声信号的幅值来检测更灵敏些。然而在这些测定 I. INTRODUCTION An acoustic signal can provide both amplitude and phase information. It has been found on many occasions that phase detection is often more effective than amplitude detection. For example, using the phase information of photoacoustic signals for non-destructive testing of the surface of a material, photoacoustic imaging [1], determination of the phase transition of a material [2], determination of the thermal conductivity of a material [3] The amplitude to detect more sensitive. However, in these assays