Birefringence measurement in twisted single-mode fibres

Abstract

A simple method is described for the determination of the modal birefringence in single-mode fibres. Measurement of the state of polarisation for various twist rates on a straight short-length fibre give the birefringence Δβ and the elasto-optic coefficient g. Linearly or circularly polarised input light can be used. The measurement range spreads from 10 to 1040/m. Comparisons are made with previously reported methods.