PLASMA TV
The first popular big (>40") thin HDTVs were plasma TVs. It is a flat panel TV where two layers of glass contain many little cells containing gas that can be excited electrically to fluoresce (give out light). "Excited" gas is called plasma. The gas shines only as long as it is excitted, so eachbubble has to receive an electric charge many times a second to give the appearance of continuous colour. This means considerable power usage.
Liquid Crystal Display Televisions (LCD TV) produce an image using thin film transistor (TFT) technology. They use less electricity. They were limited in size originally but are now able to compete in the "big-screen" market.
Digital Light Processing screens have microscopically small mirrors laid on a transitor transmit an image to a screen. It is technically a projection device but they can be made quite thin, although not quite as thin as some other types of HDTV screens.
