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Measurement of reflectance at normal incidence R and its fractional change ΔR/R caused by a change of the angle of incidence from 0 to a small angle ϕ (ϕ≲ 20°) permits explicit determination of both the refractive index n and extinction coefficient k of an isotropic absorbing medium. The medium of incidence (ambient) is assumed to have a known refractive index (e.g., =1 for vacuum or air), and the incident light is either p or s linearly polarized.

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Journal of the Optical Society of America (1917-1983)


This paper was published in Journal of the Optical Society of America (1917-1983) and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.