Interferometric measurement of arbitrary propagating vector beams that are tightly focused

Abstract

In this work we demonstrate a simple setup to generate and measure arbitrary vector beams that are tightly focused. The vector beams are created with a spatial light modulator and focused with a microscope objective with an effective numerical aperture of 1.2. The transverse polarization components ($E_x$, $E_y$) of the tightly focused vector beams are measured with 3 step interferometry. The axial component $E_z$ is reconstructed using the transverse fields with Gauss law. We measure beams with the following polarization states: circular, radial, azimuthal, spiral, flower and spider web.