Abstract

The Kubelka-Munk theory is applied to the thickness-dependent diffuse reflectance of black-painted samples in the mid-IR. The calculated absorption and scattering coefficients are wavenumber-dependent. The reflectance of the nonideal backing also shows spectral features, which is attributed to the reflections from the boundary surface between the scattering medium and the substrate. The spectral dependence of scattering penetration depth is caused by the scattering and absorption processes. At some wavenumbers, the diffuse reflectance is independent of layer thickness, because of particular values of the parameters of the applied theory. The application of the Kubelka-Munk function is discussed.

Applicability conditions of the Kubelka–Munk theory

William E. Vargas and Gunnar A. Niklasson
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Reflectance spectroscopy: application of the Kubelka-Munk theory to the rates of photoprocesses of powders

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Diffuse Scattered Radiation Theories of Duntley and of Kubelka–Munk

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Revised Kubelka–Munk theory. I. Theory and application

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Infrared Reflectance of Paints

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