Working Of A Plasma TV

Television technology for the past 75 years has been based on the technology of CRT or cathode-ray-tube. In it there are guns that fire beams of electrons, which are particles that are negatively charged inside a tube, made of glass. These electrons cause excitement in phosphor atoms located at the screen end or the end of the tube that is wide. As a result the phosphor atoms gets lighted up. The phosphor coating being lighted up on different areas with various colours with dissimilar intensities produces the image on the screen.

The images are sharp and vibrant but the sets are bulky. Thus a big screen will result in a television set that will take up a good size of the room! With necessity being the mother of invention, this difficulty has led to the popping up of a new technology leading to plasma flat panels for display. These sets have wide screen but are only a few inches thick.

A video signal lights up thousands of dots inside the monitor or television. These dots are known as pixels having highly energized electron beams. Usually pixels have three colours - blue, red and green. These are evenly spread out across the screen. Combining these basic colours in different proportions produces the entire colour show. The fundamental idea of the plasma unit is to light up minute coloured lights that are fluorescent to create the image. Each pixel comprises of three of these lights - red, green and blue. Similar to the CRT, the plasma television alters the intensity of the various lights to bring about the effect of the full spectrum of colours.

The first generation of plasma displays did not have tuners that receive the television signal and interprets that to make a video image. But today digital tuners have been assembled to the main unit.

Plasma is the central element in the fluorescent light. It is a gas that has free flowing ions and electrons. Ions are atoms that have been electrically charged and electrons are particles that have been negatively charged. Normally a gas is made of uncharged particles. Thus a gas atom usually has equal number of protons and electrons atom resulting in zero total charge. But the scene rapidly changes with the introduction of free electrons in the gas. This leads to the setting up across it of electrical voltage.

Free electrons clash with the atoms dislodging other electrons. When an electron goes missing the atom loses its balances. It becomes and ion. In the case of plasma there is electric current passing through. This causes particles that are negatively charged to rush to that region of the plasma that is positively charged; on the reverse the particles, which are positively, charged hurry towards the area that is negatively charged.

There is a mad rush and one collides into another constantly. The gas atoms in the plasma get excited. Photons of energy are now released. The atoms used in plasma displays are neon and xenon atoms. The gases of these are contained in thousands of tiny cells sandwiched between two glass plates.

Thus to sum up we find that the Plasma TV forms a picture from plasma or gas that is filled with atoms of xenon and neon as well as innumerable electrically charged electrons and atoms that bump and collide to release energy or power. The net result is that without extra bulk, the viewing area gets enlarged. Rather than being fat the Plasma TV is slim and thin. The quality of picture is par excellence but the draw back is that the cost is beyond the reach of many people.

This article can also be accessed in portuguese language from the Article section of page www.polomercantil.com.br/televisores.php

Roberto Sedycias works as IT consultant for Polomercantil