Input, Output, and Storage - Computing Fundamentals - page 60

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Figure.3 22 An inkjet printer.

Inkjet printers are popular in homes and small businesses because the
cost of the printer is very low, so it's economical to get started. However,
the ink cartridges are expensive and don't last for very many pages, so
high-volume printing on an inkjet printer can be very expensive. The
special glossy paper needed for best-quality photo printing can also be
expensive.

If an inkjet printer sits idle for weeks at a time, the ink in the nozzles dries out, and you may see quality
problems with your printouts. Running the printer's self-cleaning cycle may restore the print quality, but doing
so wastes some ink, driving up the cost per page even higher. Unfortunately there is not much you can do to
prevent this; it's just something to be aware of when selecting a printer technology.

CAUTION

Laser Printers
Laser printers are popular in business because they are fast, they handle
high-volume printing well, and the cost per page is low. They also pro-
duce good quality, high-resolution output, and both color and black-
and-white models are available. The main drawback is the initial cost,
which can be higher than for other printer types. Figure 3.23 shows a
laser printer.

laser printer A printer that forms the page
image by transferring toner to the paper via a
rotating drum with electrical charges.

A laser printer prints by creating an image of the page on a rotating drum
using varying levels of electrical charges. The drum is negatively charged,
and then a laser neutralizes the charge in some spots. When the drum
rotates past a reservoir of toner (a powdered mixture of colored plastic
particles and iron), the toner is attracted to the neutralized areas, and
clings to the drum. Then the paper rotates past positively charged paper,
and the toner is pulled off the drum and onto the paper. A fuser element
heats the paper, melting the plastic particles in the toner so that the par-
ticles stick to the paper permanently.

drum The rotating cylinder inside a laser printer,
on which the page image is formed with electrical
charges.

toner The powdered mixture of plastic and iron
used to form the image on a laser printer.

fuser The heating element in a laser printer that
melts the toner, fusing it to the paper.