This paper describes the principle and an application of a newly developed radiation thermometry, which can measure temperature and emissivity simultaneously, and also eliminate stray radiation coming from heat sources.
The system of the method is composed of a radiometer and a reflecting mirror which are disposed symmetrically at an angle θ with respect to the normal to the surface of a measured object. p value defined as a specular reflection factor is important and substantial for this method.
This system was applied to a continuous annealing furnace for cold rolled steel strips at Nagoya Works of Nippon Steel Corporation.
The accuracy was estimated to be within ±10°C.
