Tracing invisible particles (IMAGE) Technical University of Munich (TUM) Caption The researchers use a method known as Raman microspectroscopy. It works by shining a monochromatic laser source onto a sample and detecting the light scattered by the molecules. Credit Andreas Heddergott / TUM Usage Restrictions frei zur redaktionellen Nutzung unter Angabe des Copyrights / may be freely used by reporters, with proper attribution 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.