Picture near-perfect: a new era of projectors

Phillip Knutel uses a ceiling-mounted projector in a "smart classroom" during a lecture at Bentley College in Waltham. The professor says projector quality and flexibility have vastly improved. (patricia mcdonnell for the boston globe)

Bentley College professor Phillip Knutel remembers the days when you'd have to turn down the lights to use a classroom projector. While the projector would flicker in the darkness, inevitably, one or two students would fall asleep.

Those days are gone. Today's projectors are like having a flat-screen television in the classroom, says Knutel, director of academic technology, library, and research services at the Waltham school. You can leave the room bright while still showing a video or presentation.

"Past projectors pale in comparison to the ones today - no pun intended," he says.

Projectors have become an effective tool for many corporate sales staffs, used with PowerPoint presentations or Excel spreadsheets. Video conferencing and multimedia applications also are increasingly popular business applications, and some projectors are being placed outdoors as retail signs, projecting images in a store window as a changing "billboard."

Add booming multimedia worship in churches and an expanding education market, and the future of projectors looks, well, bright.

"Projectors are getting brighter and less expensive, with greater portability and more efficient operations, including longer-life bulbs and reduced fan noise," says Tim Anderson, senior product marketing manager of the 3LCD group, short for Liquid Crystal Display - a trade group dedicated to the technology that uses three semiconductor chips, red, green, and blue, for screen color.

Digital Light Processing, or DLP, projectors are another popular technology, which uses one chip and a rotating color wheel to display colors sequentially.

Brightness is one of the top factors in projector performance. This luminescence is needed to avoid a washed-out image and to compete with ambient light from windows and other light.

Projectors are rated in "lumens," a measure of perceived light power, with 2,000 lumens needed for a typical conference room and up to 15,000 lumens for a large venue.

"Brightness has doubled in the last 10 years," Anderson says.

Color accuracy and resolution - the number of pixels on a screen - also are key. In general, the higher the resolution, the sharper the image, and the higher the price tag. But good resolution and accurate color can "make or break the impact of a presentation," says Anderson. A projector should exhibit bright and accurate colors, with no blurring or separating of hues.

High-definition projectors also are beginning to shine in another market. Home theater buffs are using them to view wide-screen images for an at-home movie experience.

Some projectors incorporate DVD/CD players and speakers into one unit; others can be hooked up to a DVD player or cable and sound system, creating larger-than-life movies, photos, sports, or even video games.

Harry Shea, a commercial real estate owner in Salem, N.H., says he has two 42-inch and one 52-inch plasma televisions in his home. But his new high-resolution projector "outshines them all." Shea watches James Bond movies, ballroom dancing DVDs, and nature shows on the projector, which is mounted on the ceiling as part of his newly remodeled multimedia room.

"The whole operation is pretty slick," says Shea. But nothing beats watching the Patriots play through the projector onto a big screen. "Now, that's the best."