Information Technology Reference
In-Depth Information
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Figure.3 23
A laser printer.
Specialty Printers
In addition to the printer types discussed so far, a variety of special-
purpose printers exist. You may see some of these printers in businesses,
schools, and government offices.
Thermal printers
transfer images to paper using heat. For example, some
cash registers use a special thermal-coated paper for receipts; the cash
register contains a simple
direct thermal printer
that heats certain areas
of the paper so that it turns black and forms the text for your receipt. A
thermal wax transfer printer
melts a wax-based ink onto paper in tiny
dots, using
dithering
to create different colors. It's a high-cost, medium-
quality printout that was popular before color laser printers became eco-
nomically feasible for ordinary users, but is seldom seen today. A
thermal
dye transfer printer
, sometimes called a dye sublimation printer, heats
ribbons containing dye and then diffuses the dye into specially coated
paper. The print quality is outstanding, but the paper and the dye are
both expensive. Some small-format snapshot printers use this technology.
thermal printer
A printer that transfers images
to paper using heat.
direct thermal printer
A printer that heats
certain areas of specially coated paper so that it
turns black and forms the image.
thermal wax transfer printer
A printer that
melts a wax-based ink onto paper in tiny dots.
dithering
Placing different colored dots side
by side in an image so that from a distance they
appear to be a third color.
thermal dye transfer printer
A printer that
heats ribbons containing dye and then diffuses the
dye onto specially coated paper.
A
plotter
is a large-format printer that excels at creating high-precision
drawings like blueprints, maps, and engineering drawings. Figure 3.24
shows a plotter. Plotters that use a variety of printing technologies,
including variants of inkjet and laser, are available. On the other end of
the size spectrum, some small-format specialty printers work with their
own software to accomplish specific tasks, such as printing labels, post-
age, or work orders.
plotter
A large-format printer that creates high-
precision documents such as maps and engineer-
ing drawings.
