Fig. 6
From: Electromagnetic reprogrammable coding-metasurface holograms

The dependence of SNR for the holographic image as the function of observation distance. The red line represents SNR for the holographic image as a function of the observation distance with the adaptive adjustment of the metasurface hologram, while the blue dashed line denotes SNR for the holograph image with the observation distance fixed at Z r = 400 mm. These two lines are obtained by averaging the results of ‘LOVE PKU! SEU! NUS!’