A transparent medium for printers and plotters having optical edge and media sensors has one or more reflective strips applied to the non-image side to trip the sensors. The reflective strips can include a narrow strip along one lateral edge to locate the edge, and a wider strip along the other...http://www.google.de/patents/US5723202?utm_source=gb-gplus-sharePatent US5723202 - Transparent printer media with reflective strips for media sensing
