Abstract

The polarimetrie heterodyne interferometer (PHI) is an interesting tool for real-time detection of a rapidly changing state of polarization (SOP) of a coherent optical radiation.¹ This versatile instrument, which has been demonstrated for fiber characterization, provides amplitude ratio and relative phase of the two optical field components E_x, E_y. A more complete SOP determination (applicable also to partially polarized light) requires the use of Stokes parameters.² In the present work, this purpose has been achieved by modifying the output electrical scheme of the PHI: the two detected heterodyne signals, proportional to E_x E_y, are split and mixed together with and without 90° electrical delay to provide s₂, s₃ Stokes parameters (s₁ could be derived also from the two rf outputs, while s₀ requires an independent radiometric measurement). s₂, s₃ outputs have been tested using a Pockels cell at low frequency and properly oriented to obtain only an SOP phase modulation (with nearly 180° depth). The s₂, s₃ output curve, visualized through an x-y oscilloscope, turned out to be a circular arc as expected.

© 1988 Optical Society of America