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Interferometry. W. H. Steel, ix -f271 pages. Cambridge University Press, 32 E. 57th St., New York, Ν. Υ. 10022. 1967. $11.SO Reviewed by John Strong, Univer sity of Massachusetts, Amherst, Mass. 01003
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ANALYTICAL CHEMISTRY
This review of "Interferometry" by W. A. Steele, is an advertisement, fash ioned from the reader's viewpoint. The book supplements Candler's "Modern Interferometers," of 1951. It treats of many theoretical moderniza tions that are now part of practice ; al though some of its mathematical review is more bibliographic than didactic. The mathematical technics include the van Cittert-Zernikc treatment of coher ence, and its expanded modern applied forms. On the practical side, interferometry has been advanced mainly by develop ment of optical fabrication procedures: various new thermal evaporation pro cedures, to produce optical surfaces; and a new urgent usefulness, to meet escalating requirements of precision in industry. New or fresh treatments in the books include: the spherical Fabry-Perot in terferometer; Fourier spectroscopy; in terference imaging; lasers and holo grams; and even the latest: hologram interferometry. These fresh treatments cover new and useful concepts such as multiplexing, étendu, etc. This book is just the kind of selective epitome that the research man appreciates. Unfortunately, many items of current or burgeoning importance are absent. For example, on the instrumental side, Koester's prism (it will undoubtedly soon be an article of commerce) is not mentioned. And although Zermike's third beam method "to convert intensity to amplitude" in a fringe pattern is mentioned. Fleischmann's beautiful applications of the third beam, with a third Young's slit, was ignored. And Sinton's stellar interferometer, using achromatized fringes, is missing. The book will be particularly useful to those beginning work in interference spectroscopy; or in radio astronomy. It is certainly a must for the collector who prides himself on a selective library of useful scientific books.
