All TV screen sizes are measured on the diagonal. To determine an appropriate screen size for your viewing area, measure the distance in inches from where the television will sit to where you will watch it. Divide that number by two for your screen size.
LCD vs. Plasma
Once you have determined the size of your screen, you may not have to consider display technology. For televisions less than 40 inches, there are more LCD options than plasma ones. For more than 50 inches, the value lies in plasma TVs. Between 40 and 50 inches, you should weigh the benefits and drawbacks of each technology.
Misconceptions and Realities About Plasma TVs
When the first plasma televisions hit the market several years ago, there were quality issues related to short lifespan, poor visibility in sunlight, and burn-in. (Burn-in occurs when there is a static image on the display for long periods of time, such as a channel logo or a stock ticker.) All three issues have been addressed and have ceased to be a problem under normal viewing conditions. Plasmas, however, continue to have more trouble in direct sunlight than LCDs.
Misconceptions and Realities About LCD TVs
Viewing angle and blurring during fast-action sequences, such as those in football games and action films, used to be the plague of LCD TVs. Most of today's panels can be enjoyed from nearly 180 degrees. The blurring has disappeared only from premium sets, which refresh the picture at a faster rate. Look for sets with a 120 Hertz frame rate.
There are two ways that resolution comes into play. There's the resolution of the signal you send to your television and the native resolution of the TV itself. The TV will always display a picture in its native resolution, up-converting lower-resolution signals and down-converting higher ones. Just remember that a low-quality source, such as a VHS tape, will not look good on a large, high-quality high-definition TV. In fact, the tape may look worse.
Resolution is measured in lines of resolution, the horizontal lines that create the picture. For flat panels, the picture is painted in one pass, in a progressive scan, which is indicated by the letter "p". Older televisions that use cathode-ray tubes are the only ones that create their pictures by painting the odd and then the even lines, letting your brain fuse the two together. This older process is called interlacing and is indicated by the letter "i." If you see the letter "i" after a number indicating resolution on a flat-panel television, it is merely letting you know that the TV can read that signal, not that it will display that resolution.
For flat-panel TVs, there are three levels of resolution:
EDTV (enhanced-definition TV), which displays a 480p picture
HDTV (high-definition TV), which displays a 720p picture
Full HD, which displays a 1080p picture (some manufacturers just use HDTV to label these sets)
In general, more lines of resolution will result in a better image. There are two notable exceptions. First, screen size matters. With panels 42 inches and smaller for plasma and 32 inches and smaller for LCDs, it will be difficult to see a difference between 720p and 1080p sets. LCD TVs in resolutions lower than 1080p are subject to what's called the screen-door effect. This means you can see the little black lines that separate each pixel, or color box, on the panel. Plasma pixels have a more diffuse glow, which blurs the lines. Second, your source matters. The only source of true 1080p content today is a high-definition DVD player -- either Blu-ray or HD-DVD. If you will not be watching 1080p content on your TV, you may not need a 1080p set.
Some technologies are produced by just one or a couple of manufacturers. These features are usually found in higher-end panels and give them a visible edge.
The feature is found only in LCD TVs. It indicates that the set can display more colors because of the use of an LED or a wide-color-gamut CCFL. Regular LCD TVs are capable of producing about 80 percent of the colors found in TV signals.
Most manufacturers will list the bit depth of the set. The higher the number, the more shades of gray (and other colors) it can display.
Not all colors that the eye can see are used in TV signals. Xv color doubles the range of colors that can be produced. The downside: No commercial video sold or broadcast has been captured using the Xv color space, and only some Sony camcorders record in Xv. Therefore, you will see a difference only with video that was recorded with this expanded palette.