Self aligning fibre for a fibre optic voltage sensor

Structured Optical Fibres and the Application of Their Linear and Non-Linear Properties

“…What is remarkable about such a simple fibre is that novel variants remain possible -for example, in order to develop a practical all-fibre voltage sensor exploiting the poling effect for the power industry, the problem of alignment of the orientation of the fibre along the correct axis becomes critical (its very asymmetry that gives rise to its attractive applications now poses a new challenge). This problem was overcome by a very simple additional "structuring" of the fibre -putting flats on a twin-hole structured birefringent optical fibre used for poling makes the structure, through form-induced strain, self-aligning, a remarkably elegant solution demonstrated experimentally [Hambley et al 2008] and verified theoretically [Jewart et al 2009] -figure 2 shows the fibre and concept. For this particular example, there is no need to try and design a fancier version in, say, a photonic crystal fibre by removing holes from the otherwise periodic lattice -such a fibre is harder to make with usually lower precision, lower reproducibility and less robust.…”