A Study on Characteristics of Fundamental Performances for Thermograph

Abstract

The noise equivalent temperature difference (NETD) and the minimum detectable size (MDS) as a spatial resolution, are most important performance indices of thermogrph. For such indices, a wide variety of standards and test / evaluation methods have been defined until now, but, it is very important to establish more objective standards for the quantificaton of thermographs. This paper presents two matters, one is a new method to obtain noise equivalent temperatue difference by standard deviation of radiance temperature at individual pixels in thermogram, and the another is the necessity to clarify the relationship between the size of an object to be measured and the temperature reading. In the former, we can treat the noise equivalent temperature difference quantitatively and objectively, as this method depends upon statistical treatment, while in the latter we can quantitatively measure the temperature of the measuring object in the detectable size.