2020-10-11
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Displays, often called monitors or screens, are the most-used output device on a computer. They provide instant feedback by showing you text and graphic images as work or play.Most desktop and laptop displays use Liquid Crystal Display (LCD) technology.
The main feature of any computer display is its resolution. Resolutionrefers to the number of dots of colour known as pixels (picture elements) contained in a display. It is expressed by identifying the number of pixels on the horizontal and vertical axes. A typical resolution is 1920×980.A pixel is a combination of red, green and blue subjects.
Two measurements describe the size of your display the aspect ratio and the screen size. Historically computer displays, like most televisions, have had an aspect ratio of 4:3 – the width of the screen to the height is four to three. For widescreen LCD displays, the aspect ratio is 16:9, very useful for viewing DVD movies, playing games and displaying multiple windows side by side. High-definition TV also uses this format. The viewable screen size is measured diagonally, so a 19' screen measures 19' from the top left to the bottom right.
Inside the computer there is a video adapter or graphics card which processes images and sends signals to the monitor.
An LCD is made of two glass plates with a liquid crystal material between them. The crystals block the light in different quantities to create the image. Active-matrix LCDsuse TFT (thin film transistors) technology in which each pixel has its own switch. The amount of light the LCD monitor produces is called brightness or luminance, measured in cd/m2 (candela per square meter).
PCs can be connected to video projectors which project the image onto a large screen. They are used for presentations and home theatre applications.
