Hardware Reference
In-Depth Information
The other major technology for presentation and home theater projectors uses Texas Instruments' own
DLP technology. DLP projectors use a combination of a rapidly spinning color wheel and a
microprocessor-controlled array of tiny mirrors known as a
digital micromirror device
(DMD).
Each mirror in a DMD corresponds to a pixel, and the mirrors reflect light toward or away from the
projector optics. Depending on how frequently the mirrors are switched on, the image varies from
white (always on) to black (never on) through as many as 1,024 gray shades. The color wheel
provides color data to complete the projected image. Compared to LCD projectors, DLP projectors
are more compact, are lighter, and cool down more quickly after use. Although DLP projects were
originally more expensive than LCD projectors, they are now about the same price. Most current
projectors also support HDTV resolutions of 720p and 1080i, enabling a single projector to work as
either a PC or a TV display.
Figure 12.27
illustrates how a DLP-based projector produces the image.
Figure 12.27. How a typical DLP projector works.
The earliest DLP projectors used a simple three-color (RGB) wheel, as shown in
Figure 12.28
.
However, more recent models have used a four-segment (RGB and clear) or a six-segment
(RGBRGB) wheel to improve picture quality.
Note
For more information about digital light processing, see the official Texas Instruments website
about DLP technology at
www.dlp.com
.
Using Multiple Monitors
One of the most useful things you can do for increasing the usability and productivity of a PC is to
attach multiple monitors. Adding additional monitors gives you more screen real estate to use for
running multiple applications simultaneously. When you configure a system to use multiple monitors,
the OS creates a virtual desktop—that is, a display that exists in video memory that combines the total
screen real-estate of all of the attached displays. You use the multiple monitors to display various
