Linear to circular polarization converters based on self-complementary metasurfaces

In this work a technique for designing linear to circular polarization convertors is proposed. It is based on self-complementary metasurfaces graved on metal sheets. This kind of device can receive a linearly polarized wave and convert it into a circularly polarized wave. The main advantage over previous designs is the theoretical constancy of the phase difference between the transmission (or reflection) coefficients for two orthogonal linear polarizations, which is closely equal to 90° for any frequency.