Output device that displays information
Cathode Ray Tube Monitor (CRT) :
Displays images with colors that are consistent and can be viewed comfortably from different angles
CRT Monitor :
An economical monitor used on most systems. Images can be viewed comfortably from different angles. Available with curved or flat screens
Monochrome Monitor - Displays the image on the screen using only one color such as green, orange or white on a background of a contrast color such as black or white. Cheaper and are used with systems that do not need graphics
Gray Scale Monitor - Displays the image on the screen using different shades of gray. Can display both text and graphics like a black and white television
Color Monitor - Are useful to display colorful graphics and animations. Displays images using the three colors red, blue, and green. Mixes these three colors in different combinations to display a variety of colors
Liquid Crystal Display Monitor (LCD):
Thin and use little space
picture on the LCD monitor does not flicker and thus reduces eyestrain as the whole image is drawn at once on the LCD screen
Used in laptops, microwave ovens
TFT Monitors :
Uses Thin-Film Transistor technology
Tiny transistor is used for each pixel on the display
Allows faster re-drawing of the image
Displays sharp text, excellent color and an improved response time for multimedia applications. Viewing angles are often in a range of +-30 to +-70 degrees
Has a sandwich-like structure with liquid crystal filled between two glass plates
TFTs are actually the number of pixels displayed
Size – Specifies the length of the monitor in inches and measured diagonally. Available in different sizes ranging from 14 inches to 22 inches
Resolution – Specifies the number of pixels. More the dots, the higher the resolution, the more sharp and clear image will be displayed on the screen
Antiglare Screen – Used to reduce the glare and eye strain.
Brightness – Changes the amount of light in an image. Enables you to brighten the display picture on the screen when it appears dark and vice versa
Contrast – Specifies the difference between the lighter and the darker colors. Higher the contrast, the more is the difference between the two contrasting colors
Horizontal Size – Increases and decreases the size of the horizontally displayed image
Vertical Size – Increases and decreases the size of the vertically displayed image
Horizontal position – Moves the displayed image to the right and left directions on the screen
Vertical position – Moves the displayed image up and down on the screen
Degauss – Removes the magnetism from the monitor and restores the displayed picture
Language – Enables to modify the setting name and description on the screen
Corner/Trapezoid correction – Corrects the distortion in the displayed image
Attach signal cable to the system and power cord to the power outlet.
POST checks for the proper working of the monitor
POST also check if the monitor is receiving input from the system
Display both 2-Dimensional and 3-Dimensional images
Working of the Video Adapters
Video BIOS - A ROM chip that is built on the video adapter. Enables communication between the system and Video processor, as it understands the language of both the system and Video processor
Video Processor - Video processor is like a painter, it draws objects that must be displayed and sends them to the monitor
Video RAM (VRAM) - A memory that the video adapter uses to hold the image displayed on the monitor screen and frees up the system memory, which would otherwise hold the image displayed on the monitor screen
RAMDAC - Converts digital signals from the system to analog signals and sends them to the monitor
Problems in displaying the picture on a new monitor may be caused if the monitor is defective
Different types of problems that may occur are :
Monitor Flickering
Replacing the monitor cable
Troubleshooting the video adapter
Keep the monitor’s surface clean
Clean the CRT screen with a soft and damp cloth
Periodically perform vacuum cleaning inside the case
Switch off the monitor when not in use for an extended period
