Textile composites with integrated optical fibres: Quantification of the influence of single and multiple fibre bends on the light transmission using a Monte Carlo ray-tracing method

Monte Carlo ray-tracing simulations of the propagation of light rays along bent multimode optical fibres indicate that, for optical fibres integrated into composite components, the influence of macroscale bends induced by the component shape on the light transmission is relatively small. Mesoscale bends caused by integration of the fibres into the reinforcement fabric structure applying textile processes may cause significant transmission losses, which decrease exponentially with increasing ratio of bending radius and fibre radius and increase with increasing bending angles. Based on geometrical models of optical fibres integrated in woven fabric structures, which show multiple mesoscale bends, simulations prove that the lowest bending losses occur for fabrics with a low degree of crimp.