A method of determining internal temperatures within a semitransparent nonscattering slab is discussed. The appropriate equations and boundary conditions are reviewed and are valid for both arbitrary angles and the effects of polarization. A numerical procedure for recovering the internal temperature profile from experimentally determined, externally observable intensities is presented and shown to be both accurate and efficient. Two illustrative examples indicate the possible effects of inaccurate intensity data and how the use of polarization and various viewing angles can be useful.
Richard A. McCann,
"Determination of Internal Temperatures within Semitransparent Media by Means of Emitted Radiation," Optical Engineering 15(1), 150139 (1 February 1976). https://doi.org/10.1117/12.7971905