We all use our computers every day and we know quite a little bit about the gadgets that it has and it needs to perform at its maximum capacity but does not anyone knows how to explain exactly what is a computer monitor and what makes it so important for the computer use. The computer monitor is an output device that is part of the display of your computer.

The monitor is connected to a video adapter or a video card through a cable and it is installed on you computers' motherboard in an expansion slot. The system changes the signal into images, displays and text like on a TV like screen - the monitor. The video adapter receives a signal from the computer that tells it what kind of image, character and graphic should it display. That signal is converted by the video adapter into a set of instructions that say to the display device, the monitor, how and why to draw on the screen the imagine.



The 'picture tube' or the CRT, Cathode Ray Tube is like a large vacuum tube that is shaped like a bottle. It tapers in the back where there is a negative charged cathode or as it is called 'electron gun'. This electron gun shoots electrons to the back of the positive charged screen which has a coat of phosphorous chemical. This excites the phosphor making it glow as individual dots, as we know pixels (picture elements). The imagine that we see on the computer screen is made up from thousands of these dots, pixels.



The quality of the imagine has to do with the distance between the pixels and if the distance between the pixels is too big the imagine will appear grainy. The main issue is that the closer the pixels are the clearer and sharper would be the imagine. That distance is called dot pitch and the best monitor you should get is with .28 mm dot pitch or less. If we are to look at the computer monitor from an environmental point of view, the most difficult computer peripheral to dispose of is the monitor because of the lead that the monitor contains.

A couple of electromagnets ( yokes ) are around the collar of the tube that bend the beam of electrons which scans all across the monitor from left to right and top to bottom to draw or to create the image line by line.