A scanner case should be rigid enough to avoid any misalignments in construction. Of course, it would be best for a scanner to have a metal chassis in its base. However, many currently produced SOHO scanners come in plastic cases – to reduce their production cost. In this case, the thing is made stronger by adding special stiffening ribs.
This is where the main functional units of a scanner are located in the case
A transportation lock is another important element of the case: it protects the scan head from damage during transportation. Before turning on a scanner, you should release this lock. If you forget about this, you are running the risk of damaging the scanner. Manufacturers usually emphasize this nuance with bright labels and warning captions.
Some users think the case doesn’t influence the quality of scanning in any way. This is not exactly so. The optical system of the scanner cannot stand dust, so the case should be hermetic, without any slits or holes. I came across some models that didn’t meet this requirement, so pay attention to the case when shopping for a scanner.
A removable lid is a useful feature, too. It’s especially required when you are trying to scan thick books or magazines.
The edges of the bed should slope downwards – this way it is easier to take the original up from the glass. Besides that, there should be no clearance between the glass and the bed that would hinder your removing the original. Make sure the scanner has marking rules around the perimeter of the bed.