| Scanners
Scanner Types
While all scanners are designed for the same purpose - creating
a digital reproduction of an image or document - scanners come in
a variety of shapes and sizes designed to perform different types
of tasks. Before worrying about technical specs or reproduction
abilities, your first consideration should be what type of scanner
best suits your needs. Here is a brief rundown of the three major
types of office scanners and the functions they serve.
Flatbed
The easiest way to understand how a flatbed scanner operates is
to imagine the top of a copier sliced off its base. Essentially,
a flatbed scanner consists of its own base, with a flat piece of
glass and cover just as is found on most copiers.
The scanning
component of flatbeds runs over the length of the image in order
to gather data. Flatbeds are particularly useful when a user needs
to scan more than single page documents. Pages from a book, for
example, can easily be scanned without having to copy each page
individually first.
If you plan
on scanning objects you'll want to focus on flatbeds. By placing
a white sheet of paper over a bouquet of flowers a scanner can reproduce
what appears to be a stock photo onscreen. Flatbeds do have a large
footprint - they take up a lot of desk - so if space is a concern
you may want to consider a different type.
Sheetfed
If you know that you won't be using your scanner for anything other
than sheets of paper, a sheetfed scanner may be your best bet. Unlike
flatbeds, the scanning component of sheetfeds is stationary while
the document being scanned passes over it's 'eyes' - much like a
fax machine. Usually only a couple of inches deep, a sheetfed scanner
can easily fit between a keyboard and monitor.
Sheetfeds usually
work best in conjunction with an automatic document feeder for large
projects. While pictures and other documents smaller than a full
page can be scanned using a sheetfed scanner, a flatbed is usually
a better option for such tasks. Sheetfeds have been known to bend
pictures and reproduce less than quality images.
Slide
Slides, because of the resolution needed to accurately reproduce
very small images, do not work well in conjunction with flatbed
scanners and an entirely different scanner market has been created
as a result. Slides are usually inserted into a tray, much like
a CD tray on your computer, and scanned internally.
Most slide
scanners can only scan slides, though some newer models can also
handle negative strips. If you plan to occasionally scan slides
as well as other documents, some flatbed scanners have a magnified
portion of their glass plate for scanning slides.
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