CIE x048-OP54 PDF

Road safety is determined by the distribution of luminance created by asphalt concrete surfaces. On the one hand, experimental determination of the bidirectional reflectance distribution function is laborious, on the other hand, for some angles this task is difficult. The authors propose to use both analytical and statistical models of the luminance factor, which allow determining the luminance factors or coefficients for arbitrary angles of incidence and sighting. The models are based on the idea of a plane-parallel layer, in the volume of which radiation scattering occurs. With correctly selected optical properties of the layer (the optical thickness of the medium, the albedo of single scattering, the phase function of the particles included in the composition), the models allow obtaining reliable results, which was confirmed when compared with the measurement results. The models can also be applicable not only for asphalt concrete pavements, but also for any other surfaces.