Highly accurate calibration of polarimeters

摘要

Highly accurate calibration of a polarimeter of the type having at least four detectors involves using four known states of polarisation of an input light signal (calibration polarisations) and at least one further state of polarisation. All input states of polarisation to the polarimeter have unity normalised power of the light signal and unity degree of polarisation. A Stokes matrix for the four calibration polarisations is generated with at least one variable correction parameter, and a correction matrix is determined from the Stokes matrix and a corresponding detector current matrix measured by the polarimeter. An optimisation criterion that is a function of the degrees of polarisation for the states of polarisation as measured by the polarimeter is generated. The correction parameter is varied iteratively to minimise the optimisation criterion so that the polarimeter is calibrated to produce unity power and degree of polarisation for any input state of polarisation.