OUTPUT DEVICE

Monitor

What is it?

• The information we obtain from the computer is called an output

• The computer presenting this information is called the output device

• It is the display screen of a computer• There are several output devices:

– Monitor– Printer– Plotter– Speaker

Monitor

• It is the display screen of a computer• It is commonly used output device• Images on a monitor are made up of

thousands of tiny coloured dots called PIXELS.

• The monitor is also known as Visual Display Unit (VDU)

• The screen is the surface of monitor which display the text and pictures

Types of Monitor

• There are several types of monitor:– Monochrome monitor

• Display text and graphics in white against a black background

– Colour monitor• Display text and graphics in multiple colours

– Cathode Ray Tube (CRT)• A specialized vacuumtube in which images are produced

when an electron beam strikes aphosphorescent surface

– Liquid Crystal Display (LCD)• Displays utilize two sheets of polarizing material with a

liquid crystal solution between them

Cathode Ray Tube (CRT)

• It is the cheapest type of monitor

• It is large and bulky size

• Noisy, heavy and generates a lot of heat

• Quickly becoming outdated

Liquid Crystal Display (LCD)

• More expensive than the CRT monitor

• It is flatter and less bulky, with a higher quality display

• Consumes less electricity and is much lighter

• Become much more popular than CRT monitor

Picture Quality

• The quality of the pictures depends on the SCREEN RESOLUTION– Screen Resolution means the number of pixels

displayed on the screen

• There are two types of screen resolutions:-– High-Resolution

• The monitor screen has more pixels

– Low-Resolution• The monitor screen has fewer pixels

Colour Monitor

• Choices of colour monitor

TYPE RESOLUTION

CGA Colour Graphics Adapter LOW

EGA Enhanced Graphics Adapter MEDIUM

VGA Video Graphics Arrays HIGH

SVGA Super Video Graphics Arrays VERY HIGH