Open-source integrated optical modelling with RayFlare

RayFlare is a new Python 3 extension which aims to integrate multiple optical modelling methods in one easy-to-use environment. The resulting code is capable of modelling a wide range of solar cells with a variety of light management structures across length scales, such as planar anti-reflection coatings, distributed Bragg reflectors, large-scale textured surfaces such as pyramids, and nanoscale diffraction gratings. The methods currently included are three-dimensional ray-tracing, the transfer-matrix method (TMM), rigorous coupled-wave analysis (RCWA) and a matrix framework for coupling multiple methods across one structure. The output provided includes absorption/generation profiles, so the results can be used straightforwardly in electrical solvers. Calculations can be performed easily across wavelengths, using either custom-defined material parameters or Solcore's database to provide the correct optical constants to the relevant solvers. The modular framework means it is easy to add functionality, and the code is fully open-source and free to use.