{"id":398,"date":"2023-10-19T13:27:13","date_gmt":"2023-10-19T13:27:13","guid":{"rendered":"https:\/\/uneedtalk.com\/config\/tredword\/?page_id=398"},"modified":"2023-12-11T11:49:56","modified_gmt":"2023-12-11T11:49:56","slug":"light-sun-and-optics-applied-principles-models-and-methods","status":"publish","type":"page","link":"https:\/\/radi-cal.org\/method\/light-sun-and-optics-applied-principles-models-and-methods\/","title":{"rendered":"Light, sun and optics – applied principles, models and methods"},"content":{"rendered":"
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Light, sun and optics – applied principles, models and methods<\/h1>\n

The currently applied methods to simulate the propagation and impact of solar radiation are mainly based on geometrical optics and strongly simplified models. Hence, often without explicitly noting it, they are based on a strong level of abstraction and approximation. While this might be reasonable and often necessary from a practical point of view, it is essential to explicitly point out the underlying assumptions and simplifications made. To address this issue – and even if this may seem unconventional – this chapter includes very general parts addressing essential principles of light and physical optics. The field of light and optics is, in fact, very complex, and many models are only valid within strictly limited boundaries. Therefore, embedding the actual implementation within a broader context seems appropriate. After a brief historical overview, significant optical phenomena and models are introduced, and their practical relevance is discussed. Subsequently, more specific models and methods are introduced. Each of these later sections already contains details regarding the actual implementation and testing of the relevant models.<\/p>\n<\/div><\/div>\n

\n\n 4.1. A brief history of light<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.2. Nature of light<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.3. Light-matter interaction overview<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.4. Global radiation<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.5. Solar position algorithm<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.6. Complex-valued index of refraction functions<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.7. Generalized Fresnel coefficients<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.8. Stokes vectors<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.9. M\u00fcller matrix operations<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.10. Roughness model and microfacet theory<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.12. Inversion method to derive complex-valued refractive index functions of transparent materials<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.13. Inversion method for a generic model of diffusely reflecting, opaque surfaces<\/span>\n <\/a>\n\n<\/div><\/div>\n
\n\n 4.11. Subsurface scattering<\/span>\n <\/a>\n\n<\/div><\/div>\n<\/div>\n