Figure 4
From: Generation of E-band metasurface-based vortex beam with reduced divergence angle
(a–d) Photographs of four metasurfaces ((a) M1, (b) M2, (c) M3, and (d) M4) fabricated using the PCB process. (e) Experimental setup for near-field scattering pattern measurement. The horizontally polarized Gaussian input beam from the transmitter is incident on the metasurface with an incidence angle of θi = 15° and the vortex beam generated by the metasurface is reflected at an angle of θr = 33° and collected by the receiver with the near-field probe. By horizontal and vertical scanning of the near-field probe, the intensity and phase distribution of the vortex beam were measured.
