by Staff Writer
Projectors have uses in business and education as well as in home theaters. This projector buying guide shows some of the latest options available among large media displays, helping your understand what to look for in projectors for your business or entertainment plans.
Digital Light Processing (DLP): DLP projectors shine light onto a chip with microscopic mirrors, each mirror being one pixel of the projected image. The light is then reflected through the projector lens onto a screen. A DLP projector produces deep black and high contrast-ratio with no screen burn. The light source can last as long as 60,000 hours, and you can use it almost continuously without losing image quality. The projector lamp does burn hot, however, and must be properly cooled down to get its full lifespan.
Liquid Crystal Display (LCD): LCD projectors have tiny crystals embedded in the screen which glow red, green or blue when hit by an electrical charge. The pixels open to let light through. LCD projectors produce images with high color saturation and sharp images, which gives a high level of detail. LCD projectors work best for shorter usages, a few hours per day. Many LCD lamps are rated at 2,000 hours use, but proper cool-down can extend that life expectancy considerably.
Liquid Crystal over Silicon (LCoS): Like DLP projectors, LCoS projectors shoot light at a reflective surface. Then liquid crystals control how light is reflected to form each pixel. LCoS projectors generally have a high-quality picture with a more natural image. There is no rainbow effect, and screen-burn is nearly non-existent. An LCoS projector has lighter blacks and is generally heavier than other models. Projector lamps have varying life-spans.
Image resolution: You'll find projector resolution described with both numbers and acronyms. Higher resolution means a more detailed picture, which is especially important as the size of the projected image grows.
VGA (640 x 480): This low resolution is really only found in older televisions and computer monitors. It isn't ideal for large screens.
SVGA (800 x 600): This resolution is good enough for low-cost consumer electronics and small screens.
XGA (1024 x 768): A lot of computer displays use this resolution. This is a decent resolution for movies and TV.
WXGA (1280 x 800): This is XGA resolution in widescreen format. It works pretty well for standard-definition home theater.
SXGA (1280 x 1024): This resolution is for high-definition TV or detail-oriented professional presentations, such as architecture or engineering.
UXGA (1600 x 1200) and QXGA (2048 x 1536): These extremely high resolutions will give you a level of detail well above the capability of most Blu-ray players and other video sources.
Brightness: Any projector produces a certain amount of light. Most projectors produce a brightness, measured in lumens, of about 200 to 15,000. If you need to view the image with room lights on, you'll want a projector with a higher lumen count. Home theater projectors rated at 1,000 to 2,000 lumens are suited to a dark theater or conference room. Business or education users who have lights on during presentations will prefer projectors rated at 2,000 to 3,000 lumens. Still higher numbers are needed when in very large or very brightly lit amphitheaters. Certain projectors allow you to control the brightness.
Contrast ratio: The difference in luminance between brightest white and darkest black of an image is known as the contrast ratio. Static contrast ratio and dynamic contrast ratio are measured differently, so be sure to compare like statistics when looking at projectors. Higher contrast ratios produce more defined pictures. The static contrast ratio will probably give you the best comparison point for actual image quality.
Projector lamps: Your projector may use either incandescent bulbs or LED lamps. Many incandescent projector lamps list 2,000 hours of life or more. Some high-end models list a life of 60,000 hours. LEDs are another projector lamp option. Because LEDs have a much longer life-span than traditional incandescent projector lamps, they are quickly becoming a popular choice for home theater projectors and other applications. LEDs boast operating times in the tens of thousands of hours.
Projector care: Wipe down the projector exterior and lens with a lint-free cloth dampened with a solution of one part isopropyl alcohol to one part water. Use canned air to blow dust out of vents and openings. When you're finished using the projector, turn the lamp off. Let the projector fan run until the projector is cool. Some projectors have automatic cool-down settings.
What's dazzling video without astounding audio and video? Combine your projector with a home theater speaker system for superior surround sound. Place high-quality speakers installed around the room and you'll get theater-quality audio to match your amazing display.
Connect your computers and video game consoles to your projector for big screen video games, Web-surfing or Internet video calls.