Winfried Denk (born November 12, 1957 in Munich) is a German physicist and neurobiologist, director of the Max-Plack-Institute for Medical Research in Heidelberg. He is noted for being the first to implement two-photon microscopy while a postdoctoral fellow in Watt W. Webb's lab in 1990. Denk later (1994) recognized that two-photon microscopy has unique properties for imaging live cells deep in highly scattering tissues. His second major invention is a machine that automatically acquires three-dimensional images at a resolution of a few nanometers. This technique, known as Serial Block-Face Scanning Electron Microscopy (SBFSEM), has been commercialized by the company Gatan.[1] For his achievements, Winfried Denk was awarded the Gottfried Wilhelm Leibniz Prize in 2003.