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LCD TV
LCD stands for Liquid Crystal Display. This technology was created to replace the CRT technology.
Plasma TV
The shortcomings of LCD TV led to the development of Plasma Display Panel, otherwise known as a plasma TV. With this technology, images are created from gases containing neon and xenon atoms.
LED TV
This is basically an advanced model of a LCD TV, which uses Light Emitting Diodes instead of the traditional Cold Cathode Florescent Lamps for its backlight.
Differences
Sizes of the TV
The standard sizes of flat screen TV are 22, 26, 32, 37, 40, 46, 50, 55 and 60 inches. LED TV are available from 32 inch onwards. Plasma TV are available from 42 inch onwards.
Prices
Generally Plasma TV are cheaper than the equivalent size LED / LCD TV. LED is the most expensive.
Electricity Power Use
LED TV is the most efficient in terms of electric power use. LCD comes next and Plasmas require the most current or electric power. Plasma was notorious for consuming lots of current but now has become much more efficient.
Life of LCD and LED TV, Lifespan of Plasma TV,
All TV loses some of it brightness as the years go by.
The lifespan of a flat screen TV is defined as the working time in hours it takes for the screen brightness to become half its original brightness.
For LCD and LED the figure quoted is over 100,000 hours = 32 years (when viewed 5 hours every day).
For the life of Plasma TV the figure quoted is 60,000 hours = 54 years (when viewed 5 hours every day).
Size and Weight of TV
Just by looking at a flat screen TV you will not be able to tell whether it is an LCD or LED or Plazma TV. They all look the same. LED TV can come with a very thin profile (front to back). Plasma TV is usually the heaviest and LED TV the lightest.
Viewing Angle
Plasma TV without doubt has the best viewing angle. LCD and LED suffer from picture degradation as you move towards the sides of the TV. The picture also suffers if the TV is placed well above or below eye level.
Plasma TV Burnin
Plasma TV used to have a problem known as 'Burn-in'. Plasma TV Burnin occurs when there is one constant picture on the TV screen all the time, for example the logo of a TV station shown all the time in one corner of the TV. If you watch this TV station for a long time then that logo seems to get imprinted on the TV screen. When you watch another channel, the logo of the TV station referred to before, seems to appear as a ghost image on all channels. This is the phenomena called 'burn-in'. Now Plasma TV manufacturers have a plasma tv burn in fix to overcome this problem.
TV Brightness & Colour
LCD / LED TV normally have brighter screens and perform better in very brightly lit rooms. But under normal or dim lit rooms Plasma TV picture is better. Plasma has richer colors which appear more natural, whereas in LCD /LED TV the color tends to be oversaturated.
LCD and LED TV Motion Blur
LCD and LED TV suffer from an effect known as 'Trailing image' or 'Motion Lag'. This becomes obvious when you are watching fast action sports. For example in football the ball, and sometimes the players, moving fast appears blurred with a trailing ghost image behind. Plasma TV does not have this problem and so is usually the TV of choice amongst Sports enthusiasts.
Contrast Ratio
Plasma TV has higher contrast ratios than LCD or LED TV.