TOP DISPLAY SCREENS DEFINITION

"DISPLAY SCREEN"

 Display screens are used for inputting the data or displaying the information after processing.

"TYPES OF DISPLAY SCREENS"

There are two types of display screens.

(1) Cathode-Ray  Tubes

(2) Flat-Panel Displays.

"CATHODE-RAY TUBES  (CRT)"

The most common form of display screen is the CRT. A CRT is a vacuum tube used as a display screen in a computer or video terminal. This same kind of technology is found not only in the screen of desktop computers but also in television set and in fight-information monitors in airport. 

"HOW CRT SCREEN WORK"

A stream of bits defining the image is sent from the computer to the CRT's electron gun, where the bits are converted to electrons. The inside of the front of the CRT screen is coated with phosphor. When a beam of electrons from the electron gun hits the phosphor, it lights up selected pixels to generate an image on the screen. 

"FLAT-PANEL DISPLAYS"

The flat-panel display are much thinner, weightless, and consume less power to CRT. Thus, they are better for portable computers. Flat-panel displays are made up of two plates of glass with a substance in between them, which is activated in different ways.

"TYPES OF FLAT-PANEL DISPLAYS" 

There are three types of flat-panel displays:

(1) Liquid-Crystal Display

(2) Electro-Luminescent Display

(3) Gas-plasma Display

"LIQUID-CRYSTAL DISPLAY (LCD)"

LCD consist of a substance called liquid crystal, the molecules of which line up in a way that lighting behind the screen is blocked or allowed through to create an image.

"ELECTRO-LUMINESCENT DISPLAY (EL)"

EL contain a substance that glows when it is charged by an electric current.

"GAS-PLASMA DISPLAY"

Gas-plasma display is like a neon bulb, in which the display uses a gas that emits light in the presence of an electric current.

AT present, EL and gas-plasma technology are more expensive thus are not used as often as LCD technology.