| LCD
Projectors
Types of Technologies
While most projectors are grouped under the umbrella name 'LCD Projector,'
there are actually three different light technologies which enable
a machine to project a computer image onto a screen. Though not
substantial, the differences among these technologies are important
to recognize when comparing similarly priced models.
Single Panel
TFT (Thin Film Transistor) LCD
These LCD projectors operate by shining light through a transparent
panel of LCD cells. Tiny transistors control each LCD cell, changing
their polarity to produce the appropriate color. Together, these
LCD cells combine to display the desired image.
Since single
panel LCDs are relatively easy to produce, models that use this
technology tend to be on the cheaper side. As is usually the case,
though, a less expensive single panel LCD projector will have a
lower color quality than its more expensive counterparts.
Polysilicon
LCD
Polysilicon LCD displays share the same basic underlying technology
as single panel LCDs, but differ in one respect: instead of one
panel, there are three layers. With this type of LCD, there are
three separate primary color panels (red, green, and blue) that
are used to produce the desired color. One of the key advantages
of this design is that it tends to produce more highly-saturated
colors that the other technologies. At the same time, if you're
interested in projecting the brightest image possible, or will be
using video extensively in your presentations, a projector with
DLP technology will be more suited to your needs.
DLP (Digital
Light Processing)
Developed by Texas Instruments in mid-1996, DLP models project images
by reflecting light against hundreds of tiny mirrors known as digital
micromirror devices (DMD). Each mirror, representing one pixel,
is individually powered by electronics that adjust the angle of
the mirror according to the color being displayed. In general, DLP
projectors tend to offer brighter and more continuous images than
their LCD projector counterparts. That, along with the fact they're
leading the weight loss trend in the projector market, makes them
very appealing for presentations. DLP projectors also handle video
images extremely well. On the down side, on the average they're
more expensive and may produce a softer image than a sharp three
panel LCD.
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