A touch panel that has a front surface, a rear surface, a plurality of edges and an interior volume. An energy source is positioned in proximity to a first edge of the touch panel and is configured to emit energy that is propagated within the interior volume of the touch panel. A diffusing reflector...http://www.google.de/patents/US8149221?utm_source=gb-gplus-sharePatent US8149221 - Touch panel display system with illumination and detection provided from a single edge
