It has been more than a decade since SPIE Press published the first book on shearography in 2003: Digital Shearography: Theory and Application of Digital Speckle Pattern Shearing Interferometry by Wolfgang Steinchen and Lianxiang Yang. That book has greatly contributed to enabling better understanding and improvement of the digital shearography technique. During the past 13 years, digital shearography has been widely applied by industry and accepted as a practical tool for nondestructive testing; at the same time, the technique itself has been greatly improved. This new book presents the principles and applications of phase shift digital shearography, especially spatial phase shift digital shearography, and reviews the state-of-the-art improvements and new developments of digital shearography for nondestructive testing and strain measurement. The authors provide a unified, self-contained treatment of the theory, practice, and applications of shearographic interferometry with problems and questions. The book will meet the requirements of graduate students, as well as be of assistance in research and industry applications.

It has been more than a decade since SPIE Press published the first book on shearography in 2003: Digital Shearography: Theory and Application of Digital Speckle Pattern Shearing Interferometry by Wolfgang Steinchen and Lianxiang Yang. That book has greatly contributed to enabling better understanding and improvement of the digital shearography technique. During the past decade, on one hand, digital shearography has been widely applied by industry and accepted as a practical tool for nondestructive testing; on the other hand, the technique itself has been greatly improved. Consequently, it is time to provide the reader with the recent developments and applications of digital shearography. This new book aims to present the principles and applications of phase shift digital shearography, especially spatial phase shift digital shearography, and review the state-of-the-art improvements and new developments of digital shearography for nondestructive testing and strain measurement.

During the last decade, the rapid development of micro-electronic technology and computer science has generated many new possibilities for digital shearography and has enabled the development of spatial phase shift shearography, which is a great improvement over earlier digital shearography techniques. Spatial phase shift shearography has great potential for high-speed measurements; it fills the gap in the measurement capability of shearography for quantitative dynamic measurement. In writing this book, we have attempted to provide a unified, self-contained treatment of the theory, practice (with problems and questions), and applications of shearographic interferometry. We present the subject in such a manner that the book will meet the requirements of graduate students as well as be of assistance to the experienced researcher.

Some contents of the book draw from research carried out with Dr. Yonghong Wang, Dr. Sijing Wu, Dr. Nan Xu, Mr. Xu Chen, Mr. Jianfei Sun, Mr. Xingya Gao, and Dr. Sheng Liu. All are (or were) research assistants in the Optical Laboratory of Oakland University and are gratefully acknowledged. We appreciate the help of Mr. Junrui Li, Mr. Tian Bai, Mr. Boyang Zhang, and Ms. Haley Linkous in the careful correction of the manuscript as well as the English. Special thanks go also to Mr. Bernard Sia of US TACOM in Warren, Michigan, who carefully and thoroughly read the manuscript and provided valuable criticism. We want to express our sincere thanks to Ms. Dara Burrows, a Senior Editor of the SPIE Press, who contributed immeasurably to this book through her excellent publishing experience and her generous personal cooperation and assistance. We also gratefully acknowledge the help, comments, and suggestions offered by Dr. Y. Y. Hung, a pioneer in shearographic research.

To Dr. Yang’s wife, Yang HU, to his son and daughter, Yang and Jessica, and to Xin Xie's wife, Xiaona LI, we offer love along with our appreciation of their support and patience.

Lianxiang Yang
Xin Xie
May 2016
Oakland University
Rochester, Michigan, USA