The scanning bed (or document bed) of a scanner is where the document rests while it is being scanned. In the flatbed scanner, the scanning bed is made of clear glass. The document rests face-down on the glass as the scanning mechanism views the document through the bed. In the |overhead scanner|, the scanning bed is opaque. The document rests face-up on the bed and is viewed by the scanning sensors in an overhead sensor array. In the |paper-feed scanner|, the scanning bed is a drum, around which the document is fed. A scanning sensor views the document as it rotates past. With the |hand-held scanner|, the scanning bed can be any surface whereupon the document is set so that the scanner may be drawn across it.
