Monitors
As I mentioned in an earlier column, a monitor is the device that you watch, very much akin to your TV set, the only real difference is your monitor does not have a tuner.

There are three different types of monitors, they are Cathode Ray Tube (CRT), Liquid Crystal Display (LCD) and Plasma (Plasma). They all do the same thing, that is display the information that your computer is processing at the time, whether that is writing a letter or playing a game.

All three devices are very similar but with all things time and technology marches on. Only 10 years ago the average computer user was using a 14" or 15" CRT. Over the past ten years there have been massive jumps in technology, which translates to bigger and better for you and me. The only drawback to that is usually the cost but over time this drops as well.

I hear you asking,
"That's all very fine and good, but what are the differences. To ME?"
Good question, I will try to answer that question and many others without going into too much technical mumbo jumbo. I hope the below table helps.

	CRT	LCD	PLASMA
Screen sizes	14" - 21"	14" - up	13" - up
Case size	Large	Small	Small
Glare	Can be	No	No
Cost	$25 USED & UP	$500 & UP	$1000 & UP
Eye Strain	Yes	No	No
Eco Friendly	No	Yes	Yes

These points are really just a starting point, the meat and potatoes are as follows:

Power Consumption
CRT monitors use more energy and emit more low-frequency electromagnetic emissions.

Actual Screen Size
When you measure a CRT monitor for screen size, you start UNDER the bezel, whereas LCD's and Plasma monitors start at the edge of viewable area. So when you buy a 15" LCD you are getting almost the same screen area as a 17" CRT monitor!

Question: How do they work?
I know many of you lay awake at night wondering about this very thing, well worry no more.
CRT monitors - Simply put, the back side of the glass screen is coated with phosphor. An electronic beam is fired from the beam gun at the back of the monitor. As that beam strikes the phosphor it glows.
LCD monitors - There is two sheets of glass in the front, between these sheets is a liquid crystal solution. Behind the sheets is a bulb, when a current is passed through the liquid crystal solution, it opens and closes like a tiny shutter.
PLASMA monitors - The plasma screen also has two sheets of glass but sandwiched between these sheets is a thin layer of phosphor pixels. When a high frequency UV ray strikes them they glow.

Question: Which is better?
Answer: Well the plasma has a faster refresh rate, which means it redraws the screen faster than the others. It also sports a wider viewing angle, so you can see it better on an angle than you could if you where using a CRT.

Question: How long will it last?
Answer: Well you don't really know. Both LCD's and Plasma's are expected to last about 6 or 7 years if left on for 24 hours a day. CRT's don't really have a life expectancy, I have used many monitors that are over 5 years old. If you are a normal user, you would probably have few problems with any of the units. As time goes by and the cost of manufacturing drops, you will see LCD's and Plasma's drop in price and become far more common. Right (Feb 2004) now you can expect to pay $150-$200 (Cdn) for a 17" CRT brand new, $400 - $500 (Cdn) for a 14"LCD and over a $1000 (Cdn)for 13" Plasma. It wasn't all that long ago that a 14" CRT cost $400 (Cdn), time flys.

Question: Isn't it a Flat Screen?
Answer: I hear this a lot. People hear the term FLAT SCREEN and assume that it means an LCD or PLASMA. It doesn't. What it means quite simply is the monitor screen is FLAT. All LCD's and Plasma screens are flat but not all CRT screens are, if they are, it will help with the amount of glare you will see, but the case will not be ANY smaller.

In Summary
All I can say is I own a 14" LCD and have used it for 4 years, I would not go back to a CRT monitor. Yes, it is more money but if you spend a lot of time in front of the screen, its worth it. If you are thinking of upgrading to an LCD or Plasma monitor, go to the store and actually view one working, it will be worth your time and trouble.

If you have any questions about this topic, please feel free to email me. pc_doc1@telus.net and I will try to answer you as best I can over email.

Thank You
Mark Lewis
(The) PC DOCTOR