What is a Plasma TV?

The standard cathode ray televisions now have a high-definition alternative called the plasma TV. When high-definition content is broadcast, it provides vibrant colors and sharp images on a plasma TV. As compared to standard televisions which have a ratio of 4:3, a plasma TV has a widescreen ratio which is 16:9. Although the price of plasma TVs start from $2,000 USD, a high quality plasma TV can have a price as high as $15,000 USD and may be more too.

The plasma TV has a flat screen which is its most important selling point, as it allows the TV to be hung on the wall without taking up much area, as in case of CRT televisions. People can also use high-end receivers and surround-sound speaker systems to enhance the pleasure of watching the TV. Among wealthy consumers and tech hungry people, plasma TVs have become status symbols.

The construction of the plasma TV is not very simple. Gases like neon and xenon called plasma gases are used in them. These gases glow when they are exposed to an electric field. After the three states of matter i.e. solids, liquids and gases, plasma is termed as the fourth state. You may think of fluorescent or neon sign light bulbs in order to have some familiarity with plasma.

Small picture elements called pixels create the whole image on a television screen. A pixel is composed of three colors, mainly blue, green and red which combine to form the picture on a TV screen. However, the different colors of the spectrum are made by controlling the level of each color to form a pixel. The individual pixels get blurred into each other because the viewer is sitting far away from the TV and when these pixels change colors, an illusion of motion is created. This happens in every television whether plasma or a standard one.

But in a plasma TV, the inert gases like xenon or neon are present in three tiny containers and from these individual pixels are made. On an average plasma screen there are thousands of these tiny tubes and these individual pixels are present between two electrically-charged plates. When it is exposed to an electric current, the plasma begins to glow. The signals sent from the broadcast antenna or cables are received by the computer processing unit of the TV which further issues commands to the circuitry to reassemble the entire picture hundreds of times per second.

The electric field is controlled by a computer which also manages the individual pixels and causes the different combinations of colors to glow. As the brain of the viewer processes the information as a continuously moving image, he/she is not aware of all the changes. As compared to a standard television, a plasma TV has more pixels due to which much sharper images are obtained. An exact hue is reproduced from each pixel combination and much richer and deeper colors are observed on the TV screen.

But a plasma TV has some disadvantages too, and it is vulnerable to damage. The ability of the individual gas filled tubes is lost instantly when a hard object strikes the screen and replacement of these elements is expensive and time-consuming. So, it is recommended that plasma TV owners should extend warranties and purchase insurance as the TV has to be replaced in most such cases. Plasma TVs also have a limited shelf life due to leakage of gases which may occur, or these gases may become less reactive to the electric field. Users may also note a change in picture quality after many years, as the gases begins to flicker. This flickering is similar to that seen in fluorescent and neon lighting.

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