A simplified route to manufacturing microstructured optical fibres

Microstructured optical fibres (MOFs) are used widely in the communications industry for the transmission of data signals. They are typically constructed from glass via a drawing process and their resulting cross-sections comprising a complex array of holes and interconnecting glass 'struts'. But how do we make a MOF with a desired final cross-sectional configuration? We present a model for the surface-tension-driven evolution of the viscous struts, or viscidas, and the connecting junctions, which bears similarities to network models used for foam dynamics. A degeneracy in the model highlights the need for care when constructing the model. Crucially, the theory provides a simplified framework for predicting the evolution of a complex MOF cross-section during the drawing process. Moreover, the model is well-posed for inverse time, allowing us to predict the start configuration required to generate a desired final cross-sectional profile.