CC BY 4.0Polywka, AndreasAndreasPolywkaCarmer, Carl Friedrich Graf vonCarl Friedrich Graf vonCarmer2025-04-232025-04-232025https://doi.org/10.24406/publica-4558https://publica.fraunhofer.de/handle/publica/48688410.24406/publica-4558An additive superposition approach is presented to model the effective directional surface reflectance of optically rough fine-textured planar surfaces. As examples, effective reflectance models for randomly droplet-occupied surfaces and for periodic two-dimensional sawtooth-like fine-structured surfaces are constructed and parameterised. Comparative ray-optical simulation results confirm the applicability of the approach to effective reflectance models of optically rough, finely structured surfaces.enReflectance modellingmacrostructuresnumerical simulationBRDFconference paper