Abstract

An equation of the form nλ=2t+fλ is necessary to represent multiple-beam fringes of equal chromatic order. Experimental values of f are reported for several silver coatings of various reflectivities and ages in the working range. The experimental values of f for new coatings are independent of λ in the range 4500A to 6300A. The experimental values of f for aged coatings with reflectivities greater than 60 percent agree reasonably well with a value estimated from the known optical constants of bulk silver. The systematic error inherent in the result of determining a thickness or a change in thickness when using the elementary equation nλ=2t is of the order of one percent in the working range of age, reflectivity, and order of interference.

© 1953 Optical Society of America

Multiple-Beam Fringes of Equal Chromatic Order. Part III. The Cleavage of Topaz

W. F. Koehler and A. Eberstein
J. Opt. Soc. Am. 43(9) 747-749 (1953)

Multiple-Beam Fringes of Equal Chromatic Order. Part II. Mechanism of Polishing Glass

W. F. Koehler
J. Opt. Soc. Am. 43(9) 743-747 (1953)

Multiple-Beam Fringes of Equal Chromatic Order. Part IV. Use of Multilayer Films

W. F. Koehler
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W. F. Koehler
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Multiple-Beam Fringes of Equal Chromatic Order. Part V. Fringe Fine-Structure

W. F. Koehler and W. C. White
J. Opt. Soc. Am. 45(11) 940-944 (1955)