High accurate multi-angular polarized spectrum thermometry for smooth surface

Abstract

A new multi-angular polarized spectrum thermometry based on the optimal inversion wavelength selection method was proposed to accurately measure the surface temperature of optically smooth opaque surface. The surface temperature was inverted from the multi-angular polarized spectral radiance of sample by the least square method. The optimal inversion wavelength was iteratively determined by using the relation of λTS=2410 μm·K. The optimal inversion model was proved to be inverting the refractive index and the extinction coefficient by the ratio model P/S firstly and then calculating the surface temperature by the non-ratio model P+S. A proof-of-principle experiment with a high-purity SiC sample was carried out to validate the reliability of the inversion method. The result shows that the relative deviation of temperature is less than 1% at the optimal wavelength for the calculation performed by the optimal inversion model.