Emissivity-compensated radiation thermometry method using a concave mirror

In this work, a method to simultaneously measure the temperature and emissivity of any specimen, including metals and semiconductor materials, was developed using a concave mirror and a polarized radiometer. The ratio of the enhanced radiance after reflection off the mirror to the original radiance of a specimen allowed for emissivity determination in the range 0.1-0.9, with a variation of 8%. The combined standard uncertainty, u_c, of the temperature measurement by the current method is estimated to be 6.0 K at a temperature of 800 K. This was realized via classification of the parameter α into only three categories that were closely related to the surface roughness. Furthermore, it should be emphasized that the polarized spectral radiance measurements were carried out at a zenith angle of 75°, which contributed significantly to the success of this method.