What is a TFT Monitor?

A TFT monitor uses thin-film transistor technology in an LCD display. LCD monitors, also called flat panel displays, are replacing the old-style cathode ray tubes (CRTs) in both televisions and computer displays. Nearly all LCD monitors today use TFT technology.

A desktop computer with a TFT monitor.

The benefit of thin-film transistor technology is the separate, tiny transistor for each pixel on the display. Because each transistor is so small, the amount of charge needed to control it is also small. This allows the screen to refresh very quickly, as the image is re-painted or refreshed several times per second.

Flat panel monitors are quickly replacing old CRTs.

Prior to TFT, passive matrix LCD displays could not keep up with fast moving images. A mouse dragged across the screen, for example, from point A to point B, would disappear between the two points. A TFT monitor can track the mouse, resulting in a display that can be used for video, gaming, and all forms of multimedia.

A 17-inch TFT monitor has about 1.3 million pixels and 1.3 million transistors. That leaves a significant chance for a malfunctioning transistor or two on the panel, and "dead pixels" are not uncommon. A dead pixel is a pixel whose transistor has failed, thereby creating no display image so on a solid black background, for example, dead pixels will stand out as tiny dots of red, white, or blue. Most manufacturers will not replace a monitor that has fewer than 11 dead pixels. Many don't have any dead pixels, although even in those that do, they are not really noticeable unless they are located in a critical position on the screen.

There are only a handful of TFT factories that turn out panels for all brands of monitors. Since there is a given failure rate — considering how many transistors are on each panel — only so many of the displays come out bearing no dead pixels. A certain percentage have some, but not an unreasonable number, and other panels are unusable. The panels that have some dead pixels are often sold to be used in discount models. Consumers, therefore, should read online feedback from buyers to get an idea of the quality of particular brands. By scanning the reviews for several brands, it is easy to get a feel for which models have consistently good panels that rarely bear dead pixels.

A good TFT monitor delivers crisp text, vibrant color, and an improved response time for multimedia applications. People who are interested in gaming, video editing, or other multimedia applications should look for a monitor with a response rate of 16 ms or less.