Outward appearances are definitely deceiving when it comes to Plasma Television Technology and LCD televisions. Although Plasma televisions and LCD televisions are flat and thin, they employ different technology in an attempt to deliver similar results.

Plasma Television Technology Overview
Plasma television technology is based loosely on the fluorescent light bulb. The display itself consists of cells. Within each cell two glass panels are separated by a narrow gap in which neon-xenon gas is injected and sealed in plasma form during the manufacturing process. The gas is electrically charged at specific intervals when the plasma set is in use. The charged gas then strikes red, green, and blue phosphors, thus creating a television image. Each group of red, green, and blue phosphors is called a pixel (picture element).

Although plasma television technology eliminates the need for the bulky picture tube and electron beam scanning of traditional televisions, because it still employs the burning of phosphors to generate an image, plasma televisions still suffer from some of the drawbacks of traditional televisions, such as heat generation and screen-burn of static images.

LCD TV Overview
LCD televisions, on the other hand, use a different technology. Basically, LCD panels are made of two layers of transparent material, which are polarized, and are "glued" together. One of the layers is coated with a special polymer that holds the individual liquid crystals. Current is then passed through individual crystals, which allow the crystals to pass or block light to create images. LCD crystals do not produce their own light, so an external light source, such as florescent bulb is needed for the image created by the LCD to become visible to the viewer.

Unlike standard CRT and plasma televisions, since there are no phosphors that light up, less power is needed for operation and the light source in an LCD television generates less heat than a plasma or traditional television. Also, because of the nature of LCD technology, there is no radiation emitted from the screen itself.
 

• No burn-in of static images
• Cooler running temperature
• No high altitude use issues
• Increased image brightness over plasma
• Longer display life (about 60,000 hours - at which time all you may need to do is replace the light source, not the entire set); this can vary according other environmental and use factors

Plasma TVs are affected by altitude. Most manufacturers say that 6500 feet above sea level is the maximum operating altitude limit for a plasma TV. A few others say 5500 feet. The added pressure at higher altitudes cause the unit to work harder and, therefore, get hotter to display the picture. Most units have cooling fans (convection style or otherwise) but they, too, will be working harder to keep up with the additional strain and will, thusly, become louder. And because it is working harder, the life expectancy of the unit is greatly reduced.

No one really knows for certain as to the life expectancy of a plasma TV. The only real standard that seems to be used to judge this is based on the units some manufacturers have operating in major airports. Some have screen failure at one year (constant use). Most have done well for 22,000 hours of constant use. Take this figure and divide by the average amount a person watches TV per day. Example: 4 hours, you get 5500 days of viewing or 15 years of life. 22 hours of use per day and you get 1000 days of use or 3 years.

But the phosphors that make the color dissipate over time and that dissipation begins the moment you turn the set on. After 1000 hours, it is reported the picture brightness is reduced to 94%, which, really, is barely noticeable. Over time, though, this increases. At about 15,000 hours you get a picture quality brightness of about 65%.