Numerical modelling and investigation of a polarimetric current transducer with a spun-type lightguide

This paper discusses the features of the transformation of the polarization state of light when it propagates along a spun-type lightguide. The compensation setup of a polarimetric current transducer with a double pass of the sensitive loop is described. Based on the modelling results, a formula is derived for the dependence of the transducer sensitivity on the polarization characteristics of the lightguide and the size of the measurement loop. Results are presented from a measurement of the relative sensitivity of a prototype of the transducer.