Fundamental measurement problems in engineering, mechanics, manufacturing, and physics are now being solved by powerful optical methods. This book presents a lucid, up-to-date discussion of these optical methods. Beginning from a firm base in modern optics, the book proceeds through relevant theory of interference and diffraction and integrates this theory with descriptions of laboratory techniques and apparatus. Among the techniques discussed are classical interferometry, photoelasticity, geometric moire, spatial filtering, moire interferometry, holography, holographic interferometry, laser speckle interferometry, and video-based speckle methods. By providing a firm base in the physical principles and at the same time allowing the reader to perform meaningful experiments related to the topic being studied, the book offers a unique user-oriented approach that will appeal to students, researchers and practising engineers.

When it was learned that Professor Scholze was revising his classic work on the nature, structure, and properties of glass, it was natural to conceive the idea of translating the new edition into English. Professor Scholze enthusiastically endorsed this suggestion and asked for the concurrence of his publisher, Springer-Verlag. Springer-Verlag welcomed the idea and readily agreed to provide support. With the essential agreements in place, Professor Michael Lakin, Professor of German at Alfred University, was asked to do the transla tion, and I subsequently agreed to work with Professor Lakin to check for technical accuracy. I was happy to accept this task because of my respect for Professor Scholze and because of the value to glass scientists and engineers of having available an English edition of Glas. Professor Scholze died before publication ofthis English edition of his work. However, he had reviewed the entire English text and had approved it. Professor Lakin and I appreciated the confidence he placed in us, and we were gratified with his acceptance of our efforts. His scientific contributions were numerous and important; they will long serve as guideposts for research in many key areas. We hope this translation of Glas will help make his legacy accessible to more people. Professor Lakin and I have tried to provide a translation that is accurate and true to the original but that has a distinctive English "flavor"; that is, it is not just a literal translation.