Plasma

Basics
A plasma screen is a flat panel display where light is displayed by the use of phosphors (emit the visible light). The phosphors are excited by a gas discharge between two panels of glass. The gas discharge is a mixture of noble gases which are not harmful (comply with guidelines for TV radiation emissions). Plasma screen TV's offer a large screen area that provides excellent picture quality with low picture distortion, unlike rear projection for example.

Most screens are 42 inch (107 cm) in diagonal size upwards, makes them perfect for home theater use.
Color reproduction is great, especially the 'darkroom' contrast, which produces the ideal 'perfect black'.
They perform well under ambient light conditions. This means that bright light does not filter out the image on the screen. Therefore you do not have to turn off the wall lights in your living room to improve the screen image.
Each pixel is lit individually, so the image is very bright, over 1000 lx. For screens 70 inches diagonally.
Each pixel is lit individually so the picture looks good from almost every angle.
Total thickness of the actual device is usually only 10 cm / 4 inches.
Include a wide colour gamut for screens 80 inches diagonally.
The display panel is usually only 6cm / 2 and half inches thick.
Technology of the future, which are HDTV and Digital TV ready.

Tips

Be careful when hanging a plasma screen TV over your fireplace. Make sure the area where the plasma TV will be placed is below a temperature of 80 degrees Fahrenheit.
Do not leave static images (such as computer games on pause) on screen for long periods. This causes burn-in where a pixel is damaged. A plasma screen is more likely to suffer from burn-in during it's first 200 hours of use. Therefore it's recommended to lower the luminance by altering the brightness or contrast setting.

Terms Explained

Pixel resolution - The higher the number of pixels displayed on the screen, the higher the picture resolution will be. Currently the most common pixel resolution displayed by most TVs is 1024x768.
Native resolution - Is the standard resolution of the plasma display and not the resolution of the delivery signal.
Contrast ratio - The measurement of light intensity between the brightest white and the darkest black. Therefore you should look for the contrast ratio to be the highest possible, this will mean better picture quality.
Viewing angle - This describes the best viewing angle
HD Ready - Contains the required screen resolution and necessary connections to display high definition content. Programs should be broadcast in this format in the UK in 2006.
NTSC, PAL, and SECAM - standard video formats.
Aspect ratio - this is the ratio TV signals are transmitted in, such as 4:3 or 16:9 widescreen format (HDTV will be).

Plasma and LCD technology - what's the difference?

Plasma and LCD panels may look similar, but the flat screen and thin profile is where the similarities end. Plasma screens, as its name suggests, uses a matrix of tiny gas plasma cells charged by precise electrical voltages to create a picture. LCD screens (liquid crystal display) are in layman's terms sandwiches made up of liquid crystal pushed in the space between two glass plates. Images are created by varying the amount electrical charge applied to the crystals. Each technology has its strengths and weaknesses, as you'll read below.

What advantages does plasma have over LCD?

Apart from better contrast due to its ability to show deeper blacks, plasma screens typically have better viewing angles than LCD. Viewing angles are how far you can sit on either side of a screen before the picture's quality is affected. You tend to see some brightness and colour shift when you're on too far of an angle with LCDs, while a plasma's picture remains fairly solid. This is steadily changing, however, with more and more LCDs entering the market with viewing angles equal to or greater than some plasmas. Plasmas can also produce a brighter colour, once again due to light leakage on an LCD affecting its colour saturation.

Plasma pundits will also tell you that some LCD screens have a tendency to blur images, particularly during fast moving scenes in movies or in sports. While that was true for older generation LCD screens, newer models have improved significantly -- so much so that the differences in performance between LCDs and plasmas in this regard is almost negligible (here's a tip -- if you're shopping for LCDs, check the pixel response time, measured in ms. The lower it is, the better the image quality in fast moving scenes).

What advantages does LCD have over plasma?

Apart from being price competitive, LCD has the edge over plasma in several other key areas. LCDs tend to have higher native resolution than plasmas of similar size, which means more pixels on a screen.

LCDs also tend to consume less power than plasma screens, with some estimates ranging that power saving at up to 30 per cent less than plasma. LCDs are also generally lighter than similar sized plasmas, making it easier to move around or wall mount.

LCD pundits also point to the fact that LCDs have a longer lifespan than plasma screens. This was true of earlier plasma models, which would lose half of their brightness after more than 20,000 hours of viewing. Later plasma generations have bumped that up to anything between 30,000 and 60,000 hours. LCDs, on the other hand, are guaranteed for 60,000 hours.

You might have also heard that plasmas suffer from screen burn in, an affliction not as commonly associated with LCDs. Screen burn in occurs when an image is left too long on a screen, resulting in a ghost of that image burned in permanently. Newer plasmas are less susceptible to this thanks to improved technology and features such as screen savers, but burn-in is still a problem. But after a few days of use most burnt-in images will fade -- they are no longer permanent.