Like a television set, a monitor comprises a cathode ray tube (CRT) and supporting circuitry that processes the external video signal into a form that can be displayed by the CRT. Monitors use a different video interface than televisions, have much higher bandwidth, and can display much finer detail. In fact, with the proper adapter, computer video signals can be displayed on a standard television, but only at low resolution. Conversely, a monitor can be used to display television video at very high quality, although doing so requires using a video card with TV input, a tuner, and other electronics that are built into television sets but not monitors. The quality of the CRT and supporting circuitry determines the quality of the image a monitor can display. Because of their higher bandwidth and resolution, computer monitors cost much more than televisions with equal screen sizes.
Monitors comprise the following major elements:
The CRT is essentially a large glass bottle, flat or nearly so on one end (the screen), tapering to a thin neck at the back, and with nearly all air exhausted. The inside of the screen end is covered with a matrix of millions of tiny phosphor dots (or stripes). A phosphor is a chemical compound that, when struck by electrons, emits visible light of a particular color. Phosphors are organized by groups of three, collectively called a pixel. Each pixel contains one phosphor dot that emits each of the additive primary colors red, green, and blue. ...