Photonic detection is key to precise analyses in health, medicine, environmental monitoring, security, and energy. The latest edition of reflexion, the science magazine of Leibniz IPHT, showcases how researchers use light to unveil processes that would otherwise remain invisible. 

How can molecular processes be observed in real time? How can structural anomalies in materials be detected when they are invisible to the naked eye? How can biological signals deep within tissue be measured without harming the body? 

The answers lie in the Photonic Detection research program at Leibniz IPHT. There, light is used as a precise, noninvasive tool to analyze chemical, biological, and physical phenomena with high sensitivity and spatial resolution. 

This field is the focus of the new edition of reflexion. Following last year’s spotlight on biophotonics, this second part of our trilogy provides in-depth insight into a research area that underpins many of the institute’s scientific developments. 

The articles illustrate the full thematic range, from novel catalysts for sustainable hydrogen production and molecular sensors that could visualize biochemical activity within the body to advanced detection methods for microplastics. Medical applications also play a central role, including imaging techniques for tumor diagnostics and ultrathin, light-based endoscopes that enable observation of the brain in action. 

Environmental issues are also addressed: For example, how much microplastic from urban areas ends up in the Saale River? How can low-cost optical sensors be developed to detect pollutants early on? 

Photonic detection is the fundamental technology underlying numerous research fields at Leibniz IPHT. It involves developing optical measurement techniques that will shape the future of sensor technology, from fundamental science to clinical applications.