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LCD and Plasma: What's the Difference? What is the difference? Currently, the plasma TV is said to be aimed at size, whereas the LCD is aimed at quality—although this is rapidly changing with continued research and development, according to many industry sources. "The problem with LCDs is that they are really expensive compared to their size," says Karl DeManss, Samsung's director of New Business Development. Adds Vincent Cefalu, director of marketing for Haier America (New York City, NY, U.S.). "LCD has a better picture, but it's smaller. Plasma TVs have larger sizes—they are more for the masses." The current largest LCD screen in the world is a 57-in prototype. The largest plasma TV is 80 in.

Technologically speaking, they are also very different. LCD displays work by having a liquid crystal panel filter light from a fluorescent lamp. The LCD controls the passage of light through a polarization of light. Once light has been polarized by a certain angle with a filter, the intensity of the light can be controlled by adjusting the angle of polarization of another filter, according to the online LCD Monitor Technology Guide.

The first stage of an LCD display involves passing the light through a polarizing filter, which then gets into a layer filled with liquid crystals that are controlled by the transistors, according to the guide. The light then passes through color filters (such as with CRT monitors, each LCD display pixels consist of three components—red, green, and blue). A transistor applies voltage to liquid crystals that sets their spatial alignment. Light changes its polarization angle when it passes through the ordered liquid crystal molecular structure, and depending on its new polarization angle, it will be absorbed completely or partially, according to the guide. This allows the creation of any halftone from black to pure white.

Plasma TVs, on the other hand, have a gas. However, plasma screens do not have scan lines because every pixel cell has its own transistor electrode, according to PlasmaTVBuyingGuide. (Beaverton, OR, U.S.). The lack of scan lines creates a smooth, evenly lit image across the entire surface of the display. Most current plasma displays also include built-in line doubling to improve image quality from low-resolution video signals, notes the Plasma TVBuyingGuide Company. However, because plasma TVs use a gas, there is a half-life, and sometimes there is a problem with an image being burned into the screen. More Editorials