Fig. 6

Subwavelength imaging and edge detection results of a 1-D 60 mm (1.57λ₀) slit. a–d When the object is a 60 mm slit, the normalized spatial spectrums of received signals from empty waveguide (a), lens1 (b), lens2 (c), and lens3 (d), respectively. e, f The reverse Fourier transforms of the shaded regions k_e ∈ [0, 1] (e), k_e ∈ [1, 2] (f), k_e ∈ [2, 3] (g), and k_e ∈ [3, 4] (h) in the spectrum plotted in (a–d) correspondingly. (i) The edge image of the 60 mm slit by adding three subwavelength components. j The full image of the 60 mm slit by adding subwavelength as well as propagating components. In (a–j), black solid lines are experimental measurements, black dashed lines are simulation results, and red dashed lines are theoretical references