Luminance Imaging Measurements for Façades With Asymmetrical Light Reflection

The subject of the research is to reduce light pollution produced by architectural lighting, by decreasing the luminous flux reflected to the sky, but without diminishing the visibility of façades at night. The article is a continuation of the authors' previous article, which showed that a façade with asymmetric reflection can be obtained when using only ordinary materials with diffuse reflection. The method consists of the use of horizontal decorative microprofiles (fins), with dimensions that are easy to achieve technologically. The optimization of the geometry of these profiles is the objective of this article. For optimization, generalized modeling of light reflection in MATLAB is used, through original scripts. These scripts also automatically generate the mesh necessary for the discretization of the façade, for profiles whose angle is modified for the whole range of technologically feasible values. Based on numerical simulations, an optimal domain is identified, based on which the experimental program of effective measurements of the luminance of the façade is optimized, by using imaging.