Infrared polarization model optimization and radiation characteristics of camouflage coatings

To investigate the polarization characteristics of the infrared radiation form camouflage a coating surface, an improved model for the two-component polarized bidirectional reflectance distribution function (pBRDF) is established. A new form of the geometric attenuation factor is used instead of the traditional Blinn shielding function, and diffuse scattering component caused by the rough surface is also taken into account in the micro mirro model. The expression of the degree of linear polarization (DOLP) of the infrared radiation is derived by using the optimized pBRDF, the valid of which is proved by experimental data. The numerical calculations results of DOLP of the three coatings are in good agreement with the experimental data. The expression is numerically evaluated and the influence of coating surface roughness, the effect of geometric attenuation diffuse scattering on the infrared DOLP is discussed. The greater the surface roughness of the coating is, the more obvious are the geometric attenuation effect and diffuse scattering effect caused by the roughness. These results provide theoretical and technical support for the realization of military camouflage, anti-camouflage, target recognition, and other fields.