CALCULATION AND APPLICATION OF INFRARED EMISSIVITY

Infrared emissivity is an important parameter to characterize the optical properties of materials in the fields of radiative cooling, photothermal conversion and infrared stealth. In this paper, the infrared emissivity and reflectivity in visible and near infrared bands of SiO₂/TiO₂ composite coating system with different phase volume fraction and thickness are calculated by combining optical matrix method and equivalent medium theory. The results indicated that this method could well predict the optical performance parameters such as infrared emissivity and reflectivity of optical composite coatings, effectively improve the optimization efficiency of process parameters such as phase volume fraction and film thickness of composite coatings, and reduce the experimental workload. It is of great significance to realize the spectral selective regulation of composite coatings.