Figure 4
From: Quasi-Crystal Metasurface for Simultaneous Half- and Quarter-Wave Plate Operation

(a) Magnitude ratio of cross and co-polarized reflections. Inset shows the frequency region where metasurface exhibits ideal characteristics i.e., |Rxy|/|Ryy| = 1 necessary for circular polarization. (b) Phase difference between cross and co-polarized reflections for y- polarized incident wave.