A device that projects computer output onto a white or silver fabric screen that is wall, ceiling or tripod mounted. It is widely used in classrooms and auditoriums for instruction and slide presentations. For projectors designed primarily to display movies, see front-projection TV
A data projector has a VGA input for resolutions such as 1024x768, 1280x1024 and higher. Most units also have HDMI inputs for Blu-ray/DVD players, cable boxes and other movie sources. Older projectors support the analog TV interfaces (composite, component and S-video).
Increasingly Smaller and Lighter
In the 1980s, the first data projectors weighed more than 40 pounds, using a single cathode ray tube (CRT) to project a monochrome image. When color units came out, they weighed even more because of their three CRTs (red, green and blue). CRT projection systems have given way to smaller, more convenient technologies, although they still offer high quality.
In the 1990s, projectors became transparent LCD panels, but although significantly lighter than CRTs, they required an overhead projector for illumination (see LCD panel
). After the turn of the century, stand-alone projectors shrank to a pound or two (see pocket projector
), and within a few years to only a few ounces (see microprojector
). See extended desktop mode
The Good Old Days
Starting in 1980, Alan Freedman, author of this encyclopedia, lugged a monochrome data projector to the computer literacy classes he taught to non-technical managers. Projector, computer and rolling cases weighed over 100 pounds.
Twenty Years Later
In 2000, using Texas Instrument's DLP technology, Compaq introduced the four-pound MP1400, one of the first lightweight data projectors. (Image courtesy of Compaq Computer Corporation.)
Another Decade Later
In 2012, ViewSonic introduced its Pico projector, weighing less than a pound. (Image courtesy of ViewSonic Corporation, www.viewsonic.com)