The Measurement of Large Optic Axial Angles with the Universal Stage

M. Munro
Department of Geology and Mineralogy, University of Aberdeen

Summary: A comparison has been made of the relative speed, accuracy, and precision of several methods of measuring large optic axial angles with the universal stage. It is concluded that a method based on the direct location of a single optic axis and the application of the Biot-Fresnel law will frequently be the most satisfactory when only the standard, low refractive index centre plate for the stage is available. If a centre plate of high refractive index is employed, however, good results can normally be obtained by using the more rapid method based on the direct location of both optic axes.

Mineralogical Magazine; March 1966 v. 35; no. 273; p. 763-769; DOI: 10.1180/minmag.1966.035.273.12
© 1966, The Mineralogical Society
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