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Deciding on a DLP 2:
When looking at DLP projectors, the most important factor to consider is
the capabilities of the DLP chip, which is the heart of the system. Like LCDs,
DLPs are fixed-pixel displays, and Texas Instruments has a couple of chips
on the market with different aspect ratios and different resolutions. Early
DLP chips were designed for 4:3 video reproduction (with a lower-resolution
16:9 mode), but current models are designed for 16:9 aspect ratios.
Most DLP chips can reproduce HDTV resolutions. However, some less expensive
versions cannot. All DLP chips that we know of can reproduce 16:9
widescreen progressive scan video (which is 848 x 480 pixels), but the fancier
versions can reproduce 720p and even 1080p HDTV signals. The latest and
greatest DLP chip (given the nature of the computer industry, this will change
relatively soon) is called the xHD4, which offers a 16:9 aspect ratio and a 1920
x 1080 pixel resolution.
There’s a lot of discussion in various Internet forums about all of the different
DLP chips that TI makes and sells to display manufacturers. If you dig deep
enough, you can usually find some info about a specific chip and a specific
TV, but in fact this information is usually pretty well hidden. TI (and the display
manufacturers) tend not to speak about individual chips (like xHD3 or
xHD4), but rather about the resolution of the chips (720p or 1080p).
DLP projectors share many of the advantages of LCD models: low price, compact
size (with particularly thin RPTVs possible), and immunity from image
burn-in. They also share what many find to be the biggest of the same drawbacks:
less-than-perfect reproduction of blacks (but better than most LCD
projectors). But DLPs don’t have the screen door issue we mention earlier
and, additionally, have one big advantage over the other types of projectors
we’ve discussed so far: They are brighter (and therefore better in rooms that
aren’t too dark). In a DLP chip, light from the lamp is reflected off the mirrors,
but in an LCD, light is transmitted through the liquid crystals, which causes a
decrease in brightness.
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