3D Stokes parameters for vector focal fields

Abstract

The study is devoted to the application of the formalism of 3D Stokes parameters to the near-focal structured fields described with Richards–Wolf vector focusing theory. The distribution of the local polarization properties of these fields is characterized in the plane perpendicular to optical axes. The linear polarization parameter is explored, first tested by comparing basic loosely and tightly focused Gaussian beams and then, getting deeper insight into its descriptive capabilities, applied to different spatial modes. The distributions of the linear polarization parameter and directional cosines of polarization ellipses’ planes in the transverse plane are presented.