Spectral Directional Emissivity Measuring Technology Research Of The Infrared Stealth Material

With the development of the military stealth technology, the measuring device used to study the material emissivity and the devices with high measuring accuracy have been largely needed in recent years. The spectral emissivity of infrared stealth materials is a key parameter for the assess the performance of infrared stealth weapon systems。This article aims to establish a set of standard measurement device for the infrared stealth materials spectral emissivity. Based on the emissivity definition and the relevant national standards, the absolute measurement method with application of the dual optical path system is established. Through the comparison of the various measurement methods of the spectral emissivity, the Fourier transform spectrometer is adopted to measure the spectral emissivity.On the basis of previous work, a set of emissivity measurement device aiming at infrared stealth materials with temperature limits of-30～70℃ is established. The Fourier transform infrared spectroscopy is introduced for the measurement of the spectral emissivity and the spectral directional emissivity. The testing system has the temperature range of-30-70℃ and the spectral range of 3～5μm and 8～14μm angle rang is 0～60°. The system concludes Fourier transform infrared spectroscopy, low-temperature blackbody, sample heating furnace, optical system and etc. The furnace system based on the multi-stage thermoelectric cooler is designed. The background radiation compensation method of the Fourier transform infrared spectrometer emissivity measurement is also studied. At last, the experiments of the emissivity and the calculation of the uncertainty is carried out, showing that the feasibility of the measuring system.