The life span of the Plasma display is about 20,000 to 30,000 hours depending on a number of factors. If the set is used for an average of 8 hours a day, it will last about 7 to 8 years on the average. There will be many days where it may not be used at all, and other days where it may be used more than 8 hours. The lifespan of any TV made today is about the same.
In the LCD display TV sets, the backlight life is about 20,000 hours average. Some manufactures are saying that it will last about 30,000 or
40,000 hours, but this is with the brightness control at 50% setting. It may not be fun to watch when turned down this low.
The MTBF rating of the screen is with the brightness at maximum. After the rated hours, the brightness of the screen should be 50% of the amount from when the screen was new.
The technology to produce Plasma screens is fairly expensive. These screens do have a lower reliability factor of not only the screen but the circuitry behind it, because of inherent engineering problems. The LCD screens also have their problems as well, but are lower in cost to service. It is recommended to have a very good service contract on any of these types of TV sets. If there is a breakdown after warranty, they are very expensive to service.
One of the big problems with Plasma displays, if used with computers, or fixed graphics, is that they will burn in very easily. LCD screens do not burn in, but are not as sharp as CRT or Plasma displays. A plasma screen will normally have burn in, in about 4 hours or so with a fixed image on the screen for a period of about 3 to 4 hours. This is at 50% brightness. If there are any fixed graphics on the screen, they will eventually burn in. The burn-in problem is inherent to the design characteristics of the screen.
In about a year or so, most of the main manufactures will no longer be producing CRT type TV sets, and computer monitors. There will only be a few types of high end CRT monitors available for high end graphics and CAD work. All the technology will be mainly LCD and DLP type technology. The pricing of the TV sets using this type of technology will drop to affordable levels.
In all practicality for home use, I would not recommend to purchase a Plasma or LCD screen for home use at this time. I would go with a good high end CRT type screen at a fraction of the price. For about $3500 US it is possible to have a very good high end HDTV CRT set, that would be much cheaper to service, and will last about 30,000 to 40,000 hours average. You can get about 8 to10 years of good use out of a good CRT set. For the price of an average Plasma or LCD screen, you can buy about 5 good TV sets that are much more reliable and cheaper to maintain!
If you look at the value in relation to the cost, at this time the CRT screen is the best option. I must admit though, the pictures on the Plasma screen are very impressive. But, after about 5 years, they will not be so. I work for some companies that use Plasma displays for special displays and production use. They all have been serviced numerous times. Only the manufactures or manufacture service reps are able to service them. The out of warranty repairs were very expensive. The average repair bill was about $1500 for small problems that we were not able to do in-house. We have one with a burn-in of a graphic that was accidentally left up on it. The replacement estimate of the tube is about $5800 including the labour on this model. We may use this screen for applications that are not critical to the burn-in. The screen is 2 years old, and it may not pay to service.
If you are buying any screen that is a demo model, it is important to put up the proper tests on it, to see if there are any burn-ins, and or any damaged pixels beyond the accepted amount. When buying any of these types of technology screens, it is important to know the "bad pixel" policy for the warranty. This is very important for computer monitors as well. Many manufactures consider 3 to 5 bad pixels per quadrant to be acceptable. Some manufactures specify up to 8 bad pixels per quadrant. Some people like myself, find a burned pixel to be very annoying, especially if it is a lit one.