A simple, non-destructive method is presented for the characterization of the birefringence properties of a helically wound mono-mode optical fibre. It is shown that the Jones matrix model developed by J.N. Ross can be applied to describe them, if the polarization evolution of light is measured with respect to a local reference frame (Serret-Frenet frame). In this case the Ross model is equal to the matrix model developed by R.C. Jones for a twisted crystal. In order to use a fixed reference frame (laboratory reference frame) it is necessary to consider the rotation of the reference frame at the fibre input face produced by the fibre topology. The orientation of the helical fibre axes at the input is defined following the geometrical criteria proposed by Ross. The use of Poincare's method and Mueller calculus to rewrite the Ross model simplifies the physical interpretation of the results. The method presented provides an easy way to measure the total linear retardation induced by the fibre curvature, and to separate the circular retardation associated with the photo-elastic response of the fibre, from the topological rotation of the reference frame defined only by the geometry of the helically wound fibre.
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