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Liquid Crystal Display (LCD) Sceens

© Michael Christopher Brinton

Large monitors have been progressively getting more economical, as prices continue to fall. Whereas 21'' monitors used to cost $1500-2000 now they can be found for $900-1600. Additionally, larger monitors have come onto the market. Sony has released a 24'' CRT, it's got a large price tag, but what's next in the monitor industry? Liquid Crystal Displays are becoming more common of late. Industry analysts predict that within five years LCD screens will replace almost all CRTs. That's not to say that no one will have CRT monitors, it is just that when someone goes to purchase a new monitor they will probably be looking at a LCD as opposed to a CRT.

Why is the market moving towards LCD displays? Well, LCDs have many benefits over traditional CRT technology. In fact the only disadvantage to LCD displays are their high price, which will come down over time. A benefit of LCD screens is their very low radiation emissions, which allows them to be used in sensitive work environments (hospitals, scientific research, etc.). One disadvantage of CRT monitors is that as the screen size gets bigger, the monitor itself gets much larger and heavier. A 17'' monitor is 17'' deep on average and weighs 40-50lbs. 21'' monitors can weigh up to 90-100lbs. LCD screens typically weigh anywhere from 8-15lbs (there is a 20lb 20.5 inch LCD) depending on their size. Additionally, the depth of a LCD is much smaller, usually around 6-8 inches.

Another distinct advantage of LCD displays is their display design. Each cell can be changed individually so there is no flicker. In a traditional CRT, there are three guns (green, red, and blue) that constantly refresh the screen (usually at 72hz). If the screen isn't refreshed at a high enough refresh rate the human eye can detect screen flickering. However, since the whole screen isn't changed for a small pixel change, the worry of a flickering screen is removed.

The main drawback to LCD displays is their high price. The least expensive 13.8-inch screen I could find was priced at $995 (made by Viewsonic). The average price for 14-14.5 inch screens is $1400-1500. The prices have fallen a good bit, last year they were about $1000 more. The main reason for the high prices is that perfect LCD screens are hard to make. In each screen there are three different cells per pixel that have to be made. At a typical resolution of 1024x768, 2,359,296 different cells need to be made. Usually the number of defects required for a replacement is only 6. In the future, as the yields improve and as LCD screens become more popular, the prices will drop.