This is a complicated topic: when you’re choosing between plasma and LCD TVs, you’re actually choosing between two competing technologies, both of which achieve similar things (i.e., crystal-clear, color-filled pictures) and come in similar packages (i.e., super-model-thin cases). To complicate the decision-making process further, price is rapidly becoming a non-issue here.Despite all these similarities, these technologies differ as to how they process and display incoming video/computer signals.
Plasma technology consists hundreds of thousands of individual pixel cells, which allow electric pulses (stemming from electrodes) to excite rare natural gases-usually xenon and neon-causing them to glow and, thus, produce light. This light illuminates the proper balance of red, green, or blue phosphors contained in each cell to display the proper color sequence          from the light. Each pixel cell is essentially an individual microscopic florescent light bulb, receiving instruction from software contained on the back electrostatic silicon board.

Whether spread across a flat-panel screen or placed in the heart of a  projector, all LCDs are pretty much the same. A matrix of thin-film transistors (TFTs) supplies voltage to liquid-crystal-filled cells sandwiched between two sheets of glass. When hit with an electrical charge, the crystals          untwist to an exact degree to filter white light generated by a lamp behind the screen (for flat-panel TVs) or one shining through a small LCD chip (for projection TVs). LCD monitors reproduce colors through a process          of subtraction: They block out particular color wavelengths from the spectrum          of white light until they’re left with just the right color. And, it’s          the intensity of light permitted to pass through this liquid-crystal matrix          that enables LCD televisions to display images chock-full of colors-or          gradations of them.

PICTURE CONSIDERATIONS:

CONTRAST
Plasma technology has certainly achieved quite high contrast ratios. Panasonic has even boasted that its plasma displays have a 3000:1 contrast ratio, which is the measure of the blackest black compared to the whitest white. Plasma displays achieve such impressive black levels by using internal algorithms to block the power to particular pixels in order to render a pixel “dark” or black. While this can limit a plasma’s gray          scaling, it does produce exceptionally black blacks.
LCD (liquid crystal diode) displays, by contrast, utilize electric charges          to untwist liquid crystals, which causes them to block light and, hence,          emit blacks. The higher the voltage passing through the liquid crystals          in a given pixel, the more fully those crystals untwist and effectively          block light-all of which makes these pixels darker. This is a complicated          process. And, despite recent improvements in LCD black levels, even the          best LCD displays (like those produced by Sharp) have yet to break the          1000:1 contrast-ratio barrier. Though, at 700:1, many of the best quality          LCD panels display sufficiently dark blacks to please even the most discriminating          eyes.
Advantage: Plasma. For scenes with a lot of dark and light images shown          simultaneously-as with content originating from DVDs, video games, and          NTSC TV signals-plasma TVs will consistently outperform LCD TVs.

COLOR SATURATIONIn plasma displays, each pixel contains red, green, and blue elements,          which work in conjunction to create 16.77 million colors. Insofar as each          pixel contains all the elements needed to produce every color in the spectrum,          color information is more accurately reproduced with plasma technology          than it is with other display technologies. Not only are the chromaticity          coordinates more accurate on most plasma displays, the color saturation          resulting from the pixel design of plasma displays is remarkable.
LCD displays reproduce colors by manipulating light waves and subtracting          colors from white light. This is an inherently difficult template for          maintaining color accuracy and vibrancy-though most LCD displays manage          quite well. While color information benefits from the higher-than-average          number of pixels per square inch found in LCD displays (especially when          compared to plasmas), LCDs are simply not as impressive as plasmas with          similar pixel counts.
Advantage: Plasma, with the following caveat: While plasma displays are          especially good for moving images, LCD technology is better at displaying          static images with particular crispness and even coloration.

VIEWING ANGLEPlasma manufacturers have made much of their 160° viewing angles,          which is about as good as horizontal and vertical viewing angles get.          This owes to the fact that each pixel is lit by itself, not from some          central light source. Hence, each pixel is more readily visible because          its brightness is consistent with every other pixel on the screen.
LCD manufacturers have done much to improve their displays’ viewing angles.          The substrate material on newer-generation LCDs by Sharp and NEC has helped          to expand those units’ viewing angles, though they have a long way to          go before catching up with those on plasma units. Expect the best LCD          displays to have between 130- and 140-degree viewing angles. So there          persists a noticeable difference between the two technologies when viewed          in real world situations (up and down, side to side).
Advantage: Plasma

FUNCTIONAL CONSIDERATIONS:

COMPUTER USELCD monitors display static images from computer or VGA sources extremely          well, with full color detail, no flicker, and no screen burin-in. Moreover,          the number of pixels per square inch on an LCD display is typically higher          than other display technologies, so LCD monitors are especially good at          displaying large amounts of data-like you would find on an Excel spreadsheet,          for example-with exceptional clarity and precision.
Plasma, on the other hand, does not handle static images especially well          insofar as “burn-in” is still a major issue with these monitors,          as is distortion resulting from lower-resolution panels displaying static          images at expanded sizes. Finally, while video images look good on plasmas,          there can be some flicker, depending on the quality of the unit and the          resolution it’s displaying.
Advantage: LCD, except at “harsh” viewing angles.
VIDEO PLAYBACKPlasma displays get the nod here because of their excellent performance          with fast-moving images, high contrast levels, color saturation, and overall          brightness.
While the “response time” of LCD TVs has markedly improved          in the last couple of years, they still suffer from a slight “trailer”          effect, where the individual pixels are just slightly out of step with          the image on the screen.
Advantage: Plasma

USING YOUR UNIT AT ALTITUDE There is a reason why LCD panels are the preferred visual display units          for use on airplanes: LCDs aren’t affected by increases (or, for that          matter, decreases) in air pressure. Their performance is consistent, regardless          of the altitude at which they’re utilized.
Not so for plasma TVs. The display element in plasma TVs is actually          a glass substrate envelope with rare natural gases compressed therein.          So, at high altitudes (6500 feet and above), an air-pressure differential          emerges, which causes plasma displays to emit a buzzing sound. Increases          in the amount of power required to run the unit and heightened stress          on fans to cool it are the root of this buzzing noise, which sounds rather          like the humming of an old neon sign.
Advantage: LCD, at 6500 feet and higher.

LONGEVITY LCD manufacturers claim that their displays last, on average, 50,000          to 75,000 hours. In point of fact, an LCD TV will last as long as its          backlight does-and those bulbs can actually be replaced! Since this is          nothing more than light passing through a prismatic substrate, there is          essentially nothing to wear out in an LCD monitor.
Plasma, on the other hand, utilizes slight electric currents to excite          a combination of noble gases (i.e., argon, neon, xenon), which then glow          red, blue, and/or green. This is an essentially active phenomenon, so          the phosphoric elements in plasma displays fade over time. The half-life          of these gases is approximately 25,000 to 30,000 thousand hours. At this          point, the phosphors will glow half as brightly as they did when the set          was new. There is no way to replace these gases; the display simply continues          to grow dimmer with use.
Advantage: LCD x 2. LCDs are especially good for long-haul applications          like 24/7 signage.
SCREEN INTEGRITYLCD technology is not prone to screen “burn-in” or “ghosting”          the way plasma technology is. On plasma displays, static images will begin          to “burn-in,” or permanently discolor the pixels displaying          it, after only a short time-just 15 minutes or so, in some cases. Though          such “burn-in” can be reduced or “washed out,” doing          so reduces the overall lifespan of the display unit itself.
Advantage: LCD

OTHER CONSIDERATIONS:

PRODUCTION SIZE & COSTThough both plasma and LCD panels are difficult to produce in large sizes,          plasma has proved the easier of the two to manufacture in the 60- to 63-inch          category. Though such mammoth monitors are expensive, they exhibit none          of the “kinks” one might expect with such large displays. In          other words, even the largest plasma displays are reliable.
The substrate material for LCD TVs has proved difficult to produce in          large sizes without pixel defects owing to faulty transistors. NEC produces          the larges LCD display at the moment, and it measures 40″ diagonally.          Sharp has begun to mass-produce 37-inch widescreen LCD panels.
Advantage: Plasma. Even though production costs and retails prices have          come down for both technologies, plasma still has the edge as far as production          cost and capacity go.
VOLTAGE REQUIREMENTSBecause LCDs use florescent backlighting to produce images, they require          substantially less power to operate than plasmas do. LCD displays consume          about half the power that plasma displays consume. The reason: Plasmas          use a lot of electricity lighting each and every pixel you see on a screen-even          the dark ones. These are truly power-hungry devices.
Advantage: LCD x 2.
Review Date 6-3-2004

By Phil Conner