Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Martin Schadt (1938), PhD, is a Swiss physicist and inventor. In 1970 the physicists Martin Schadt and Wolfgang Helfrich invented the twisted nematic field effect (TN-effect) in the Central Research Laboratories of F. Hoffmann-La Roche Ltd, in Basel, Switzerland. The resulting patent CH532261 was licensed world-wide to electronics and watch industries and thus initiated a paradigm change towards flat panel field effect liquid crystal (LC) displays.