In a laboratory at Nottingham Trent University, a tiny device is doing something that would have seemed impossible just years ago: reshaping itself every 20 milliseconds to perform completely different optical functions. No mechanical parts. No bulky lenses. Just light, reshaped on command.
The technology behind this feat is called a virtual metasurface—a flat, programmable surface that can bend, focus, and steer light in ways traditional optics cannot. Unlike physical metasurfaces, which are fixed once manufactured, these virtual versions exist as patterns projected onto a device called a spatial light modulator, which controls light pixel by pixel, faster than the blink of an eye.
The breakthrough, published in the journal Advanced Photonics Nexus, could mark the moment metasurfaces move from laboratory curiosity to real-world technology. "This new category of emulated, virtual metasurfaces can be a game-changer," said Professor Mohsen Rahmani, a nanotechnology and photonics researcher at Nottingham Trent. He draws an analogy to the transition from the physical universe to the metaverse: a digital world that mimics reality without being constrained by it.
The implications are significant. Traditional infrared cameras require expensive semiconductor sensors and bulky separate optics to capture invisible infrared light. The new approach bypasses this entirely—turning infrared signals into visible wavelengths that any standard camera can detect, while simultaneously adjusting focal lengths on demand. Conventional lenses and mirrors cannot perform both functions at once.
The team, working with collaborators at the University of Brescia in Italy and Nankai University in China, demonstrated the technology by generating images at arbitrary focal lengths and converting invisible infrared into visible pictures in real time. Metasurfaces themselves are thousands of times thinner than a human hair and can bend, color, and steer light—but their fixed nature has long been their limitation.
"Perhaps the best analogy is the transition from universe to metaverse," Rahmani said. "Our virtual metasurfaces can be dynamically reshaped every 20 milliseconds, offering a completely distinct function each time within small gadgets and devices."
Dr. Ze Zheng, the study's first author, frames the shift as analogous to moving from analog to digital. "Replacing physical metasurfaces with virtual metasurfaces can be viewed as a transition from analog optical components toward more flexible digital platforms," she said. "This approach enables compact optical systems with enhanced programmability, multifunctionality and reduced fabrication constraints, offering a promising route toward next-generation microscopes, cameras and imaging devices."
Associate Professor Lei Xu adds that the virtual metasurfaces function like an imaginary toolbox containing every optical component at once. By combining them with artificial intelligence, the researchers can unlock multimodal capabilities with enormous potential for everyday applications.
The technology could eventually impact imaging and microscopy, quantum photonics, sensing, beam steering, semiconductor manufacturing, telecommunications, and holography. While additional research and development is needed before commercialization, the foundation is laid for devices that are smaller, smarter, and far more versatile than anything using today's fixed optics.