Abstract
Previously, we proposed a method to determine simultaneously the true temperature and the emissivity of a plane object. It uses a non-linear emissivity modification brought by the multiple-reflection occuring when a half mirror is put closely and parallel to the object. It is assumed that the distance between the object and the half mirror is negligibly small in comparison with the size of them.
In the previous method, an estimation error is caused by incomplete multiple-reflection of radiation between the half-mirror and the object which takes place when the condition is not satisfied.
In this paper, the modified emissivity is modeled as a function of the ratio of the distance to the radius of a circular object and scattering property of its surface. This model is empirically found to be applicable when the ratio is less than ∼0.6.
The original method is refined and the error is corrected by an algorithm based on the model. Its validity is confirmed by the experiment.
