The number one question is obviously: Which is better, LCD or Plasma? - When choosing between plasma and LCD flat screens you are deciding between two competing technologies, both of which offer great features and come in similar packages. To complicate the thought process further, price and size are two previous considerations that are rapidly becoming non-issues as LCD TVs are now being made in larger sizes and at competing prices with plasma.

Despite their similarities, the two technologies are very different in the way they deliver the image to the viewer.

PICTURE CONSIDERATIONS

CONTRAST / BLACK LEVELS
Plasma technology has achieved high contrast ratios, (a measure of the blackest black compared to the whitest white). Many plasma display manufacturers boast a contrast ratio of up to 10000:1 these days but this is possibly questionable.

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. Furthermore, a plasma TV uses the most power when it is producing full white. As a result, some 2nd tier manufactured brands of plasma TVs have an audible buzz or whining sound when displaying white or very light images.

LCD displays, by contrast, utilize electric charges to twist and 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. As opposed to plasma, LCD TVs use the most power when displaying a very dark or black image. This is a difficult process, and despite recent improvements in LCD black levels, only the best LCD televisions have managed to topple the 1000:1 contrast ratio barrier. The one continual drawback here for LCD is off axis viewing, when black levels consistently drop and image is very “cloudy”.

Conclusion: LCD TV manufacturers have made great improvements in black levels and in some cases have managed to match the contrast ratio of plasma displays. However, Plasma displays still maintain a clear advantage in this category due to the fading blacks when viewing LCDs from off axis. For scenes with a lot of dark and light images shown simultaneously - as with content originating from DVDs, video games and standard TV signals - plasmas still consistently outperform LCD TVs.

COLOUR ACCURACY

In plasma displays, each pixel contains red, green, and blue elements, which work in conjunction to create in the region of 16.77 million colours. Insofar as each pixel contains all the elements needed to produce every colour in the spectrum, colour information was more accurately reproduced with plasma technology than it was with other display technologies. Though the colour saturation resulting from the pixel design of plasma displays is remarkable, LCD technology has nearly caught plasma in grey scaling colour accuracy. Plasma continues to exhibit more richness in colour and more natural coloration.

LCD TVs reproduce colours by manipulating light waves and subtracting colours from white light. This is an inherently difficult process for maintaining colour accuracy and vibrancy - though most LCD displays manage quite well. While colour information benefits from the higher-than-average number of pixels per square inch found in LCD televisions (especially when compared to plasmas), LCDs are simply not as impressive as plasmas with similar pixel counts. LCDs however, produce a typically brighter picture. Greens sometimes look over-green and reds can run a bit warm, but in a room with bright outdoor lighting, an LCD TV would be preferable.

ADVANTAGE: Preference to plasma but depends upon room light, manufacturer and model. Plasma colour richness and naturalness will prevail in rooms with lower to normal lighting. LCDs will be better in very brightly lit rooms due to their inherent anti-glare technology and brightness.

VIEWING ANGLES

Plasma 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 produces its own light, rather than light being spread across the screen from one central source. Hence, each pixel is more readily visible because its brightness is consistent with every other pixel on the screen. One consistent area of superiority of plasma viewing angles is demonstrated when viewing dark material content, especially DVDs. A Plasma display holds the black levels from off axis, while LCD TVs lose black level intensity more as the angle off axis increases. This usually occurs after around 90 degrees.

LCD TV manufacturers have done much to improve their displays' viewing angles. The material on newer-generation LCD models by Sharp and Sony have helped to expand those units' viewing angles, though they still have some ground to cover before catching plasma. Expect the best LCD HDTVs to have between 120 and 130 degree viewing angles.

ADVANTAGE: Plasma