PC Hardware A Beginner’s Guide

(^414) PC Hardware: A Beginner’s Guide
Resolution graphics in the range of 240 × 216 to 360 × 360dpi. A typical dot matrix printer
is more likely to support around 75dpi printing for NLQ print.

Color Dot Matrix Printers

There are such things as color dot matrix printers. Some require the addition of a color kit

to the printer, but for the most part, the color capability, if available, is built-in. In order to

print color, a dot matrix printer must have this capability included in its firmware be-

cause a character’s color must be blended from multiple colors that are included on the

printer ribbon. Changing a color-enabled dot matrix printer from a single color to multi-

plecolorsusuallyonlyentailschangingtheribbon.Theprinter’sdevicedriversandinter-

nal firmware take care of translating the color coding of the print image into a printed

color image.

The ribbon of a color dot matrix is divided horizontally with two to eight color ribbons.

The print mechanism shifts the ribbon up and down to place the correct color in front of the

print head as needed. As you can probably guess, a dot matrix printer is not the most effi-

cient way to produce color documents, such as charts, graphs, and desktop publishing doc-

uments. Inkjet printers are far better for this purpose and typically cost less.

Inkjet Printers

Like most of the really great technology discovery stories, inkjet technology was discov-

ered by accident when a researcher at Canon, Inc. heated a syringe filled with printer ink

with a soldering iron. The heat caused a bubble of air to form in the shaft of the syringe.

Eventually, the bubble grew and forced ink out of the syringe. This discovery led to the

development of what Canon called the bubble jet printer. Although Canon still refers to

their printers as bubble jets, the industry has adopted the term inkjet for these printers.

Inkjet technology has advanced over the years to the point where it is now used in ap-

plications that range from simple text-only documents to complex graphic designs. The

Figure 17-10. The three major components of a dot matrix printer’s printhead