A display that makes use of plasma.

When voltage passes trough the gas (usually a neon/xenon mixture), it forms weakly ionized plasma, which emits UV radiation. This UV makes the phosphors emit visible light.

These phosphors work in a similar way as those in a regular CRT TV or monitor, but operate at a lower voltage. Therefore, in order to produce enough light (to yield a bright image), they draw a lot of current. This causes the well-known problem of burn-in, which together with the high power usage is the main disadvantage of plasma displays (not forgetting their high price of course).

Three of these (colored) gas / plasma cells make up one pixel in a PDP. Plasma cells are difficult to make in small dimensions, so that is the reason you don't see small PDPs.

The Plasma Display was one of the first displays used in portable computers. Most plasma displays glow with an orange colour. They work by ionizing neon gas. As the voltage over the gas rises over ca. 100V the process starts. The optimum operating voltage is about 200V. This type of display has a good contrast (about 30:1) but the light intensity is low (30-35cd/m2).

The last few years a new type of plasma display has been available. This display is built up of many enclosed cells arranged in a grid pattern. Each of these cells contain a gas mix that emit ultraviolet light when ionized. This UV light in turn makes a phosphor light up. By arranging these cells in a RGB-triplet, a colour image can be produced.

When the gas has been 'lighted', it can be sustained by a lower voltage. This means that by having an extra electrode in each cell and let it supply a sustained voltage the cell can continue to emit light until the next refresh cycle. This means that you have a active screen (similar to Active Matrix LCDs) but without the need for thin film transistors.

Though this screen type is relatively thin it is also heavy so a wall might have to be reenforced to take the weight.

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