Denis Kalkofen is a phd student at the Graz University of Technology, Austria. In 2004 he received a Dipl.-Ing. degree in Computational Visualistics from the University of Magdeburg, Germany. Since 2005, Denis is a member of the Computer Graphics and Interactive Systems group at TU Graz which is headed by Prof. Dieter Schmalstieg. His current main research interests include augmented reality, virtual reality, real time graphics, medical visualization and 3d user interfaces.