激光超声是一项新兴的技术，可应用于非接触检测。本文作者研制的探测超声微振动的激光外差干涉仪，该装置具有结构简单，不必采用复杂的反馈回路，只要采用简单的滤波就可以消除外界环境引起的干扰，更重要的是它的测量结果与干涉仪的初相无关，为实际应用提供了很大方便。 Laser ultrasound is a new technology that can be applied to non-contact detection. The laser heterodyne interferometer with ultrasonic vibrations, which is developed by the author in this paper, has the advantages of simple structure and no need of complicated feedback loop. As long as the simple filtering can eliminate the interference caused by the external environment, more importantly, its measurement result Has nothing to do with the initial phase of the interferometer, for the practical application provides a great convenience.