Programmable metasurface generates dozens of holograms at once

Over the past few decades, engineers have developed various devices that can create holograms, three-dimensional (3D) or two-dimensional (2D) images produced by precisely controlling the shape and direction of traveling light waves. Holograms are now widely used to produce visual representations of objects and to measure their physical properties, authenticate documents or bank cards, and serve as visualization tools in some educational settings.