Dual-Channel Binary Gray-Image Display Enabled with Malus-Assisted Metasurfaces

Metasurfaces composed of anisotropic nanostructures possess the ability to manipulate the polarization and intensity of light simultaneously, which paves an emerging way to construct multiplexing metadevices capable of displaying gray images with high resolution and reliability. However, previous multiplexing metadevices for gray-image displaying are mostly based on nanostructures with varied geometries and/or supercell design strategies, which complicate both the metasurface design and manufacturing or decrease the information resolution. Here, benefiting from the orientation degeneracy implied in Malus's law, we show that gray-image multiplexing can be implemented simply by a single-sized nanostructure-design approach. Specifically, by configuring the four-step orientations of silver nanobricks, two independent information channels can be established to store different gray images into a single metasurface. We experimentally demonstrate the Malus-assisted metasurface, which functions as a dual-channel gray-image display device to record two independent binary gray images without crosstalk. With the single-sized design strategy, each nanobrick can record information of two channels, and the proposed metasurface simultaneously owns an ultrahigh information density of 84 667 dots per inch for both of the two gray images. With advantages such as simplicity in nanostructure design, ultracompactness, high resolution, broadband working windows, and high security, the proposed metasurfaces empower advanced researches and applications in anticounterfeiting, information hiding, information multiplexing, ultracompact image displaying, high-density optical storage, integrated and multiplexed nanooptoelectronics, etc.