Fig. 3. (Color online) The photographs and microwave near field distributions of the real copied 10000 won bill. (a) Photograph of the real 10000 won bill. (b–d) Microwave near-field distributions of the real 10000 won bill measured at 11 GHz, 12 GHz, and 13 GHz, respectively. (e) Photograph of the copied 10000 won bill. (f–g) Microwave near-field distributions of the copied 10000 won bill measured at 11 GHz, 12 GHz, and 13 GHz, respectively. The black dashed rectangle indicates the region where the microwave near-field was visualized. The red and white dashed circles indicate positions of hologram marks in optical and microwave near-field images.
© NPSM
