A Reconfigurable Transmissive Metasurface for Dynamic Focusing

Reconfigurable metasurfaces, have been studied by many researchers due to the multifunctional capability. However, most reconfigurable metasurfaces work on reflective mode, suffering from feeder blockage. In this article, we propose a reconfigurable transmissive metasurface, which is able to dynamically focus beam and other tasks. The unit cell of the metasurface, composed of two substrates and two PIN diode, has 1 bit phase resolution (0 and 180°). The magnitude of the transmissive coefficient is above 0.8, promising a good focusing efficiency.