Circularly-Polarized Beam-Controlling Metalens

In this paper, we present a three-layer flat transmission-type circularly polarized metasurface based on Generalized Snell's Law, for beam controlling at 35GHz. Firstly, metasurface is designed to refract normally incident circularly-polarized plane wave by 270 and 420, respectively. Secondly, the electromagnetic waves can be focused at a distance of 9λ away from the metasurface, and the focal spot radius is about 0.4λ. It is shown that the metasurface will provide a new beam control method for imaging applications to achieve nearly diffraction-limited imaging performance and miniaturized devices.