Fig. 5: Spatial variations of chirality for information encoding.
From: Chirality encoding in resonant metasurfaces governed by lattice symmetries
a Mechanism of encoding information in transmission image. Each scale of the resonator corresponds to a different level of transmission signal at a target wavelength ω0. b Mechanism of encoding information in chirality through changing the rotation angle β of the resonator within a unit cell. c Optical image of the metasurface encoding two different images in transmission signal and chiral signal. The inset shows the SEM image of the metasurface area encoding 6 × 6 pixels of the original image. d Reference images. Top: a photo of an Australian cockatoo for encoding in transmission signal. Bottom: photo of Swiss Matterhorn mountain for chiral encoding (adapted from a public domain image (CC0), originally available at Pixabay https://pixabay.com/photos/matterhorn-switzerland-zermatt-1301802/). e Transmission (top row) and chiral signal (bottom row) images recorded from the encoding metasurface with square lattice design. f Respective images recorded from metasurface with hexagonal lattice design.
