Retroreflective spatial-polarization interferometer

The interference of the beams reflected from a combination of two deployed cube-corner reflectors with a special interference phase-shifting coating is considered. It is shown that in this case a beam with an axisymmetric polarization structure appears. Particular attention is paid to the various optical vortices, which are formed if polarization of light is circular. It is proposed to use this system to create a retroreflective interferometer, in which the spatial polarization structure sensitivity changes due to the path difference between the beams, reflected from two different corner-cube reflectors. It is installed such that the position of the plane of vector E oscillations rotates with azimuth variation in the transverse plane, while at different angular distances from the beam axis this rotation can occur in opposite directions, i.e., we observed a counter-twisted polarization structure, useful for manipulating small particles.