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Reviewed by: Bryan Pizzuti [02.19.02]
Manufactured by: Microtek


Differences in Monitor Technologies

Currently, there are 3 monitor technologies in widespread use. They are Cathode Ray Tube (CRT), Liquid Crystal Display (LCD) and Plasma. They are significantly different in cost, construction, and performance, and I will deal with them one at a time.

CRT Monitors

CRT monitors, as the name implies, are constructed using a tube with three light guns (or Ray guns) at the back. The ray guns swivel and shoot their light beams at the front of the monitor, creating a picture. They create each dot individually, and move VERY quickly, thereby giving the impression that the picture is created almost all at once. However, they don’t move INFINITELY fast, so at times there can be what’s known as 'flicker' which is caused by the guns not moving fast enough to make the picture. The movement of the guns is expressed in terms we have come to know as 'Refresh Rate'

The dots are created by shining the light from the guns through one of two types of material, creating two subtypes of CRT monitors. The standard type, which is known as Shadow Mask, places a material in front of the screen (on the inside) which contains a multitude of holes in it. The combination of the focusing of the guns and the size of the holes in the shadow mask material determines the minimum pixel size or "Dot Pitch" of the monitor. The other type is called Aperture Grill, and is more commonly known as "Trinitron," "Diamondtron," "Avitron," and many other such "-tron" names. Instead of placing a material with holes against the screen a series of vertically placed wires are put in instead, and are held by between 1 and 3 horizontal stabilizing wires (which are visible when looking carefully for them). By only using wires instead of holes, Trinitron technology allows more light from the color guns through and also more precise focusing, allowing a sharper picture with deeper color. It’s also more expensive to make, and therefore to buy. Both technologies adjust the resolution of the picture by adjusting the size and firing locations of the guns’ beams.

This same technology is currently (and has always been) used in televisions as well, in a mostly similar manner. The only difference is that in most TVs intended to be viewed in North American and Japan (and other countries that use the NTSC standard that I can't recall at this moment), instead of going across every line with the guns, they go across every OTHER line on their way down, and then, on the next downward pass, hit the lines they didn’t hit before. This is why CRTs tend to be the cheapest monitor technology in use, since the technology itself has been in use since the 1960s and has been refined to make mass production easier and cheaper. Because they contain so much glass, though, they tend to be heavy, and larger monitors (19 inch and up) tend to be over 40 pounds. (My 27" Sony Wega TV weighs well over 100 lbs! -Ed)

Plasma Displays

These may or may not have been in use before LCDs; I have seen monocolor IBM dumb terminals using plasma displays. Why? I have no idea. The technology is still comparatively expensive, and I don’t know much about it. I do know that it’s a flat panel technology where all pixels light up all at once, unlike CRTs. They’re also something has been unable to test.

LCD Monitors

If you’ve used a laptop, then you’ve used an LCD monitor. They’ve been around for 20 years now, which is why they’re starting to get cheaper. Also, anyone wearing a digital watch or who plays handheld games is using a more primitive sort of LCD display. They’re made by sandwiching a layer of electronic crystals suspended in a liquid between two pieces of glass. Each crystal can shift color individually, and makes up one pixel. Since there are always a fixed number of pixels contained in an LCD, there is a resolution called "Native Resolution" which is simply the exact number of crystals contained in the LCD (in the case of this monitor, 1280x1024).

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