広領域シュリーレン法と歪および主応力測定への応用

抄録

Several methods of filtering the Fraunhofer diffraction plane in the double diffraction system have been studied to measure the optical phase distribution of large variation at one time. “Sine amplitude filter” and “grid cut off filter of gradient pitch” are found to be suited for “widerrangeschlieren method.” These methods are more excellent on the range width and accuracy of measuring the optical phase distribution than conventional schlieren or interference method. They are applied to analyses of strain and principal stress. Using reflection and transmission arrangements placed a polarizer before a sample can discriminate the effect due to variation of absolute refractive indices of a strained material from the effect due to variation of its thickness.