Researchers at the University of California San Diego have developed an optical device that reveals hidden images and changes colors in response to different levels of humidity. The technology, published in Light: Science & Applications, could lead to the development of new anti-counterfeiting labels, secure data storage, interactive displays and environmental sensors. Link to the published study: Reversible optical data storage and encryption enabled by phase-change and hydrogel integration https://www.nature.com/articles/s41377-026-02330-5 Reported in May 2026 submitted by /u/Choobeen [link] [comments]