Measuring and traceable methods of spectral irradiance and ultraviolet irradiance

This paper mainly discusses the measuring and traceable methods of spectral irradiance and ultraviolet irradiance in order to advance the accuracy of the two quantities. The contents include: 1.The working principal of the primary standard apparatus of spectral irradiance and spectral radiance and the value transferring methods of spectral irradiance. 2. The traceable methods of ultraviolet irradiance to spectral irradiance primary standard apparatus. 3. Introduce the international comparison of spectral irradiance and the comparison of irradiance responsivity of UV detectors. 4. The influence factors that decrees measuring accuracy of UV radiometer and the capability evaluated methods. We put forward a fitting function of spectral irradiance of standard lamp and an optimizing method for parameters. The relative deviation of the fitting function is acceptable comparing to the uncertainty of national primary standard of spectral irradiance lamp. We also defined evaluated capabilities of UV radiometers to reflect the instrument condition and promote measuring accuracy.