Document scanning system with tethered platen element providing sheet-fed and platen scanning functions

A scanning system supporting platen and sheet-fed scanning of documents comprising:

• a first scanning unit with a first enclosure housing a first set of mechanisms for sheet-fed, double-sided scanning functions, said first scanning unit further comprising a connection to a computer;
• and
• a second scanning unit with a second enclosure, attached to said first scanning unit through a first tether interface, and including a second set of mechanisms for single-sided platen scanning of documents wherein:
• said first tether interface provides for power from said first scanning unit to said second scanning unit;
• said first tether interface transmits digital information between said first and second scanning units;
• said first and second scanning units are physically separated;
• and
• wherein a unit control and image processing electronics contained in said first scanning unit handles data control and camera movement for both said first scanning unit and said second scanning unit.