To evaluate the performance of these projectors, the PC World Test Center used a battery of tests that included text files (several Microsoft Word and Excel document screens) and an assortment of still images supplied by the ICIA's InfoComm Projection Shoot-Out DVD. We also conducted motion tests with DVD movies and a video game to see how well the devices could display fast-moving images without creating artifacts.
The projectors in this roundup represent the three core front-projection display technologies: Texas Instruments' Digital Light Processing, liquid crystal display, and liquid crystal on silicon. Nine models used DLP, six LCD, and one LCoS. Though we saw some performance differences, our tests failed to establish any technology's superiority over the others for general use.
TI's DLP technology uses a multisegment color wheel that, advocates say, produces brighter, higher-contrast images than competing technologies do. Meanwhile, front-projection LCD technology employs three LCD glass panels to display the red, green, and blue components of a full-color (RGB) image simultaneously. Supporters claim that LCD projectors generate richer, more natural color than do most DLP business models, which typically use a single-chip design with a four-segment color wheel to display red, green, blue, and white.
Unlike DLP and LCD projectors, which are commonplace, LCoS models remain a rarity. LCoS--a hybrid of DLP and LCD systems--is touted for its realistic color representation; however, it remains expensive (Canon's Realis SX50 sells for $4999).
Besides coming from a range of technologies, the projectors we tested represent a wide range of brightness levels. At the low end is the Plus V-339, rated at 1300 ANSI lumens (an industry-standard measure); this model's lumens rating means that it should be bright enough for use in small conference rooms of up to about a dozen people, either in darkness or with low ambient light, or for use when playing movies. At the other end of the spectrum are models like the NEC LT35 (our Best Buy) and the eighth-ranked Panasonic PT-LB30U, both rated at 3000 lumens. For larger rooms and environments with more ambient light, higher-lumens-rated models such as those are a better match.
We evaluated each projector at its native resolution and default factory settings. Most of the devices are rated at native 1024 by 768 resolution, as are most business notebooks we've seen recently. We also tested two models with a native 1400 by 1050 (SXGA+) resolution: the Canon Realis SX50 and the $3599 Dell 5100MP. Both of these relatively expensive projectors missed our Top 10 chart--and not just because our scoring system rewards lower-priced products in this category.
Since the still images in our tests are native 1024 by 768 resolution, the Realis SX50 and 5100MP had to use interpolation to show them full frame. Interpolation typically results in less-than-perfect displays of text, and that's what we saw here: Both SXGA+ models presented slightly fatter (blockier) text than the XGA models did, a result that underscores the importance of matching your computer's resolution with the native resolution of your projector. In informal tests that we conducted at their native SXGA+ resolution, the Realis SX50 and 5100MP did a much better job of displaying sharp text. The difference in resolution didn't seem to hurt the two projectors on our graphics tests, however; each earned above-average scores on those measures.