Polarization conversion cube-corner retroreflector.

Polarization conversion cube-corner retroreflectors rotate the major axis of the incident electric field by 90°. We show that polarization conversion cube-corner retroreflectors cannot be created with isotropic reflecting surfaces, but can be created by incorporating nonisotropic reflecting surfaces. Two types are considered-cube corners with surfaces having elliptical eigenstates and cube corners having subwavelength gratings. Implementations that use subwavelength surface relief phase gratings are investigated, and three examples are shown.