Projector Resolution and Aspect Ratio

Understanding projection terminology

Resolution refers to the clarity of detail in your projected image, measured by the number of pixels the projector can display. An XGA display, which is standard resolution for most computer presentations, has a resolution of approximately 786,000 pixels, or 1024 by 768 pixels. These are some of the resolutions you may come across when comparing projectors:

SVGA (800x600)

XGA (1024x768)

SXGA (1280x1024)

WVGA (854x480)

WSVGA (1024x576)

WXGA (1280x720)

The resolution of a conventional television is only 640 by 480 pixels. HDTV (high definition television), on the other hand, demands projectors with the highest resolution in order to maintain the video signal’s clarity and definition.

HDTV resolution

High definition television uses slightly different terminology to talk about resolution, so if you’re looking for a home theater projector[Home Theater Projectors]you’ll probably see specs like 480i (which refers to standard TV), 480p, 576p, 720p or 1080i. The ‘i’ and the ‘p’ indicate interlaced output or progressive scan output, while the numbers refer to lines of resolution.

The true, fixed or native resolution of your projection system is the highest number of pixels the machine can display. This is not the same as the projector’s maximum resolution, which describes the highest resolution the unit can process and convert to match its native settings. If the video or data signal doesn’t match up with the projector’s native resolution, it converts or scales the image (by expanding or compressing it), which can result in a loss of clarity or sharpness. Buying the most compatible projector, or adjusting your computer to the projector’s native resolution, will get you a better image.

Aspect ratio

Resolution specs change slightly when you’re dealing with widescreen projection, although it’s not really a matter of image quality - it’s about aspect ratio. Old-fashioned overhead projectors tend to favor a square 1:1 aspect ratio, while traditional televisions and computer monitors display their images in an aspect ratio of 4:3 (sometimes referred to as full screen) - the standard size for most computer-driven education and business presentations. Widescreen movies and high definition TV signals have a 16:9 aspect ratio, so many home theater consumers prefer a projection system with an aspect ratio to match. Most projectors allow you to view both 4:3 and 16:9 sources but will fill in the empty sections of screen with black bars, unless you attach an anamorphic lens[Lamps and Lenses] to optically distort the source image to match the aspect ratio of your projector. If you’re investigating the multimedia projector market you may also come across widescreen projectors with a 15:9 aspect ratio. Ideally, the aspect ratio of your source and projector should be the same, but don’t sacrifice resolution along the way.