The reading edge used what is known as a book edge scanner. The scanning
area comes right to the edge of the flat bed so one puts the fold of the
book on the edge, one side on the flat bed and the other is pointed
downward at 90 degrees to the flat bed. These scanners are a standard
product. The advantage of the one in the original post is that both sides
can be put on the scanning surface and the distorted text at the crease is
interpolated by software to reconstruct it.
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ic|xc
