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Scintillator- and ï¬bre-based particle detectors are an indispensable tool in high-energy par-\nticle physics, medical physics and other ï¬elds of application. The potentially very low light\nyield, down to a few photons, of the optical detector components in combination with the\ninevitable light transport to photodetectors necessitate an optimal design and detailed un-\nderstanding of such detectors. Thus, very detailed simulations are needed, which require\na very accurate modelling of the optical physics (optics, scintillation, wavelength-shifting\neï¬ects,...), of the optical material properties, and of the optical components. To allow for\na reliable usage also by less experienced users, the necessary complexity and ï¬exibility of\na suitable simulation framework must not lead to an increasing danger of user mistakes.\nAdditionally, the required eï¬ort for creating or modifying a detailed simulation has to be\nminimised in order to allow for the fast creation of ï¬exible simulation setups.\n\nIn the scope of this thesis, these challenges have been addressed by developing the general\nsimulation framework GODDeSS. It is an extension of the particle-physics simulation tool\nGeant4 and allows for the easy simulation of optical detector components, especially com-\nbinations of scintillators, optical ï¬bres, and photodetectors. To achieve this, the creation of\nsimulated setups is automated as much as possible: The material properties of the optical\ndetector components are speciï¬ed via easy-to-read text ï¬les and new object classes allow\nfor an easy creation of scintillator tiles, optical ï¬bres, reï¬ective wrappings and paints, and\nphotodetectors with basically a single line of code per created object. This results in an\nincrease of ï¬exibility and at the same time in a reduction of complexity. The user can create\nextensive setups within a few lines of code and typical mistakes are avoided, as the pecu-\nliarities of Geant4 regarding the conï¬guration of the optical physics processes are treated\nautomatically by the GODDeSS framework. All this makes GODDeSS an excellent approach\nto simplify the detailed simulations of optical detector components, which are necessary for\ndesigning modern particle detectors and for understanding their response.\nThis thesis introduces the GODDeSS framework, its classes, and its functionality. Further-\nmore, the extensive eï¬orts to validate it against manufacturer data as well as against test\nmeasurements with prototype setups will be presented. Additionally, detailed simulations\nhave been performed in order to investigate the optical properties of optical ï¬bres and of the\ncharacteristics of the response of detector modules.