Understanding Technical Specifications

The best way to evaluate new monitors is to go to a local store and look at them to compare the images on many screens. But most retailers have a very limited number of makes and models, so it's extremely difficult to find out which monitor offers the best combination of appearance, features, and price. Many online retailers offer a wider range of monitors than any local retail outlet, but when you order by mail or through the Web, you can't preview a monitor before you order it.

Therefore, the independent reviews in magazines and Web sites can supply valuable, if subjective, information about currently available monitors. For more objective information, compare the lists of features and specifications for each monitor model.

If you can't evaluate a monitor before you buy it, make sure the seller offers a reasonable return policy. If you discover that you don't like the images on a monitor as much as you expected, you should be able to return for full credit or a refund within a reasonable period of time.

The most important specifications of an LCD monitor include:

• Dimensions: The size of a monitor is based on the diagonal measure of the screen, from the upper left corner to the lower right corner (or vice versa, of course). In an LCD monitor, the entire screen is visible, but the frame (also called the bezel) of a CRT monitor extends over the edges of the screen by almost an inch on each side. So the visible area of an LCD screen is bigger than the same-sized CRT. In practice, the difference means that an LCD monitor provides almost the same viewing area as a CRT with a screen two inches bigger.

• Aspect ratio: Aspect ratio is the proportion of the screen's width to its height. The most common aspect ratio for computer monitors and traditional TV screens is 4:3. Widescreen LCDs and HDTV screens use a slightly wider aspect ratio of 16:9.

• Optimum resolution: The optimum resolution is the native resolution of the monitor's screen in pixels. It might also be listed as recommended resolution. This is the resolution that provides the best appearance because it uses one physical screen address for each pixel. Any other resolution forces the monitor to scale the image.

• Contrast ratio: The contrast ratio is the difference between pure white and pure black. Larger contrast ratios are better, but it's more important to think about the relationship between a monitor's contrast ratio and its brightness; more contrast is possible in an image on a brighter screen.

• Brightness: The brightness of an LCD screen is the maximum amount of light a solid white screen can produce, measured in candelas per square meter (cd/m²). Brighter screens are easier to use under bright ambient light, such as sunlight. Both brightness and contrast are adjustable, so it's always possible to reduce them when the screen is too bright for the space in which it is being used.

• Pixel size: Pixel size or pitch is the size of the individual dots in a CRT screen (smaller is better). In an LCD monitor, the pixel pitch is the same for all screens with the same size and native resolution.

• Response time: You may remember this from earlier in the chapter; response time is the amount of time in milliseconds (ms or msec) it takes a liquid crystal to change from blocking light to allowing light to pass through to blocking it again. Faster response time is better because full-motion video (games, DVD movies, and TV programs) can smear or produce ghosts if response time is too slow.

• Viewing angle: The viewing angle of an LCD screen is the maximum angle at which a user can see the image without losing brightness, color, or contrast. The viewing angle is expressed in degrees from extreme left to extreme right or from bottom to top of the range.

Other important features and functions include:

• Analog or digital inputs: The input connectors on your monitor must match the outputs on your graphics controller. If the monitor and the video card both have analog and digital connectors, use a digital cable to connect them.

• Screen surface: Some LCD monitors have matte-finish screens that reduce the amount of glare and reflected light from overhead lighting. Others use a more reflective surface that can enhance contrast. Neither is better than the other; the choice is purely subjective. Remember that where you place your screen makes a lot of difference with glare.

• Bezel color: The case that contains the monitor and the frame around the screen are usually either beige or black.

• Built-in speakers: Some monitor cases incorporate speakers into the frame that surrounds the screen. These speakers might be more convenient and less intrusive than separate speakers, but they also add to the cost of the monitor. If you're serious about using your computer to listen to high-fidelity music and other audio from DVDs, CDs, or streaming Internet sources, you want to use separate speakers that can produce better sound than the ones in a monitor.