If you're thinking about assembling a home theater system, you may be looking at large screen televisions as the heart of your system. Projection TV could give you the size that you want -- CRT screens generally top out at 40" (101 cm) or so, and at that size, they are huge and heavy. Plasma screens can be bigger than that and still manageable, but they can be extremely expensive. Projection TV technology can create large screen sizes at a reasonable price.

Or maybe you need to equip a room, like a classroom or conference room, for multimedia presentations with a large audience. A projection TV gives you a lot of flexibility and is usually much better than the standard combination of a 35mm slide projector, overhead projector and TV/VCR.

Photo courtesy Philips Research
Projection TV display in the lab showing a bright, contrast-rich, high resolution picture on a 64-inch screen

In this article, we will look at the technology of projection TVs and portable projectors, and find out how they work to display such large, clear images.