The 3D and 2D far-field scattering patterns of coding metasurfaces 5 and 6 at 1.2 THz. (a) Coding metasurface 5 with pre-designed coding sequence of 0, 1, 2, 3, 4, 5, 6, 7/0, 1, 2, 3, 4, 5, 6, 7/4, 5, 6, 7, 0, 1, 2, 3 along x-direction. (b) Coding metasurface 6 with pre-designed coding sequence of 0, 1, 2, 3, 4, 5, 6, 7/0, 1, 2, 3, 4, 5, 6, 7/4, 5, 6, 7, 0, 1, 2, 3 along y-direction.