[Principles in the design of surface temperature measurement method via radiation approach]

The fundamental issues in the design of surface temperature measurement method via radiation approach are discussed in this article, such as the spectral and directional complicacy of thermal radiation, the optical design, and the electrocircuit design. A generalized equation for the analysis of temperature measurement method via radiation approach is proposed. The method of absolute value and relative value is compared. Calibration should be made in the absolute value method but not in the relative value method. The former method is not suitable for the measurement of temperature fields while the latter method is.