An embodiment of a media quantity sensing device and a media type sensing device includes a first, a second a third, and a fourth electrode. The first electrode is positioned above a media tray and the second electrode is positioned on the media tray below the media. The third and the fourth electrodes...http://www.google.fr/patents/US6157791?utm_source=gb-gplus-shareBrevet US6157791 - Sensing media parameters
