Fig. 14

The machine-learning imager. a The illustration of the machine-learning metasurface imager for different scenes. (from Fig. 1 of Ref. [82]). b The schematic of the training process using PCA method. (from Fig. 1 of Ref. [82]). c The designed 2-bit coding element. (from Fig. 1 of Ref. [82]). d The illustration of a real-time imager for a moving person behind a wall. (from Fig. 2 of Ref. [82]). e The images of the tested person. (from Fig. 2 of Ref. [82]). f and g The reconstructed image using PCA and random projection. (from Fig. 2 of Ref. [82]). Reproduced with permission from Ref. [82] under a Creative Commons Attribution 4.0 International License