Prof. Dr. Stefan W. Hell

The resolution of light microscopes has physically been limited by the wavelength of light. Now we have developed the first fluorescence microscopes capable of providing images with a resolution of fractions of a wavelength from the interior of a cell. A combination of two of our approaches, namely 4Pi and STED microscopy, makes it possible to achieve resolutions under 40 nanometers along the optical axis. This enables us to observe biological structures that are 2000 times thinner than a human hair. We are now trying to find out whether and how we can achieve resolutions in the range of a few nanometers so as to use the technology in biological and clinical fundamental research.