Introduction
Plasma TVs are the latest alternative models to the standard cathode ray tube (CRT) televisions that have been in vogue for many decades now. A Plasma TV gives viewing experience in an altogether different league in every respect- sharp images and vivid colors in conjunction with high definition broadcasts. Plasma TVs are usually designed in wide screen formats in the ratio 16: 9. This makes all the difference against standard TV measurements which are in the ratio 4:3. However plasma TVs are very expensive, with prices starting at $4000 USD and going up to $15,000.
Benefits
One reason why a plasma TV is hot is its flat screen, which enables it to be mounted on the wall. Those who go for plasma TV usually also buy surround-sound theater speakers and advanced receivers to get the feel of a complete theater at home. Small wonder these have become the ultimate status symbols for the wealthy and the techno savvy all over the world.
The Technology
The technology behind plasma televisions is very advanced and complicated. Let us attempt to have a simplified version here.
The term ‘plasma’ usually refers to a state of matter that usually occurs with gases like neon and xenon, when they are exposed to an electrical field. This idea is the most suitable as we proceed with the explanation of the term here.
As we know, the display on a television screen is created by thousands of tiny dot like elements called pixels. Each pixel is made up of three separate colors- red, green and yellow. By adjusting the level of these three colors, the whole spectrum can be produced in each pixel. The colors blend and the viewer who is far from the screen gets the illusion of motion. This is the basic principle behind the visual experience we get from all TV screens, plasma or CRT.
In the case of plasma TVs, the pixels are created out of containers of an inert gas like neon or xenon. There are millions of such tiny containers on a plasma TV screen. All of these tubes are placed between two electrodes (electrically charged plates). When the TV is switched on, a current is created between the two electrodes, inducing plasma state in the gas tubes sandwiched between the electrodes.
Also included in the plasma TV is a computer processing unit that converts signals from the cable or antenna, which enables it to reassemble the picture and refresh it several hundred times per second. The computer unit has control down to the individual pixels and thus it controls the color combinations. The plasma screen has many more pixels than the CRT screen, so the picture quality is much better. The image is sharper and the colors are deeper and richer in the plasma screen.
Drawback
That said, one can’t help noticing the fragility of the plasma screen. The plasma screen is quite vulnerable to damage from fall or collision with hard objects. This causes the gas filled tubes to lose their ability to glow. It can be highly expensive and time consuming to replace these tubes. Therefore it is always advisable to purchase extended warranties for your plasma TV and also insure it.
Another aspect is the limited shelf life of the plasma screen. The gas filled tubes are quite prone to leak and reduced reactivity to charge. Although it may take years to notice the effects, the cumulative changes are irreversible.
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