Vigilant Windows (IMAGE) Fraunhofer-Gesellschaft Caption The invisible light of a UV lamp "illuminates" the window panes and generates fluorescent radiation in the coating. This radiation is detected by sensors in the edges of the window. Credit Fraunhofer IAP Usage Restrictions The picture may be used for editorial purposes only. It is protected by copyright. The use is free of charge if the reference is mentioned. 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.