Fluid-Switchable Smart Glass (IMAGE) Optica Caption Researchers created a prototype smart glass that is retroreflective (left) and becomes clear (right) when a liquid with optical properties similar to the reflective structure is pumped into a chamber in front of the structure. Credit Keith Goossen, University of Delaware Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.