Holographic Interferometry in Experimental Mechanics

Book excerpt: This monograph deals with diverse applications of holographic interferome try in experimental solid mechanics. Holographic interferometry has experienced a development of twenty years. It has enjoyed success and suffered some disappointments mainly due to early overestimation of its potential. At present, development of holo graphic interferometry is progressing primarily as a technique for quantita tive measurements. This is what motivated us to write this book - to ana lyze the quantitative methods of holographic interferometry. The fringe patterns obtained in holographic interferometry are graphi cally descriptive. In the general case, however, because they contain infor mation on the total vectors of displacement for points on the surface of a stressed body, the interpretation of these interferograms is much more complicated than in typical conventional interferometry. In addition, the high sensitivity of the method imposes new requirements on the loading of the objects under study. New approaches to designing loading fixtures are needed in many cases to ensure the desired loading conditions. The wealth of information obtained in holographic interferometry necessitates the use of modern computational mathematics. Therefore, practical implementation of the various methods of holographic interferometry must overcome sub stantial difficulties requiring adequate knowledge in diverse areas of science such as coherent optics, laser technology, mechanics, and applied mathe matics. Experimental methods play a significant role in solid mechanics.