(updated August 4, 2005)
The iPod-looking HP ep7120 exemplifies the user-friendly budget projector.
CRTs are also used in front-projectors; think of those three-tube monstrosities that hang from the ceiling in the coach compartments of older airplanes. We won't discuss them here, however, namely because CRT projectors are quite expensive and are generally reserved for high-end, custom installations, where they put the local cineplex to shame.
DLP and LCD projectors, on the other hand, often cost much less than their rear-projection cousins. Both technologies project the kind of huge picture--from units as small as a shoebox--that you enjoy at the theater.
Upside: Good black-level performance.
Downside: Rainbow effect.
Forecast: More and more manufacturers are leaning toward DLP--especially among inexpensive
Much like rear-projection models, front-firing DLP projectors beat out LCDs when it comes to making inky blacks. On the flip side, a few viewers may also see the rainbow effects that we described in the DLP rear-projection section.
The least-expensive DLP projectors use SVGA-resolution chips (800x600). That resolution is not high enough to display full HDTV, but it's nearly sufficient to capture every line of wide-screen DVD, which calls for 852x480 resolution. In practice, most of these models look well detailed with both HDTV and DVD. Step-up models offer higher resolutions and provide a corresponding increase in detail with high-def sources. However, only the 1,280x720 versions can display every detail of 720p HDTV, and their 16:9 aspect ratios are tailor-made for home theater.
Upside: Less expensive than DLP projectors of the same resolution.
Downside: Black-level performance not quite as good as DLP.
Forecast: The advent of cheap DLP models is forcing LCD to improve in every regard, as well as drop in price.
LCD and DLP are very close in terms of performance, and even LCD's ability to produce good blacks--often expressed as a contrast ratio in projector specs--has improved quite a bit. DLP still enjoys a slight edge, however, balanced by the fact that HD-resolution, 1,280x720 LCD projectors cost significantly less than DLP projectors of the same resolution. Otherwise, LCD offers a similar selection of resolutions as DLP models.