四光束载波全息光弹性法的研究及应用

Four Beam Carrier Holo-photoelastic Method and Its Application

本文同时利用一台激光器的相干性和两台无位相联系的激光器间的非相干特性,提出了一种新的全息光弹性法,并用于等和线的测量上.该方法具有载波频率连续可调,一次曝光给出某一载荷下的等和载波条纹图的优点;通过滤波解调,能方便地给出模型受力过程中任意两个载荷下的差载等和线,为不能重复性实验(如裂纹扩展)提供了新的实验研究方法。

A new holo-photoelastic method for measuring isopachies is proposed by using the coherence of a laser beam and the incohernce of two laser beams without phase relation simultaneously.The spatial carrier frequency f_0 can be continuously adjustde.It is interesting to note that only one exposure is needed to obtain acarrier isopachic fringe pattern under certain load,and a clear load difference isopachics under two arbitrary loads can be given through fil- tering.This provides a new way of test for nonrepeatable experiments such as crack extension.