Plasma or LCD - Which type of display is right for you?

Though both LCD televisions and plasma HDTV sets come in the form of slim flat panel displays, yet from a technology perspective, these two flat-panel technologies process the image in a totally different manner.

Plasma uses a matrix of tiny gas plasma cells that are charged by precise electrical voltages to emit light and hence to create the picture image.

Liquid Crystal Display (LCD) panels - work by trapping a liquid crystal solution between two sheets of polarized glass. When an electric current is passed through the liquid crystals, they change the polarization of the light passing through them in response to the electric voltage - as a result of which, more or less light is able to pass through the polarized glass on the face of the display.

It is not the scope of this article to go into the actual details of how these different display technologies process the image - after all, what really matters is not what is going behind the screen but rather how these different display technologies perform as a television screen.

At the same time, it is worth taking note that it is these same differences that gives each of these display technologies, its strengths and weaknesses, and that therefore renders one more suitable than the other in certain circumstances.

The list below highlights the most important differences between these two flat panel display technologies:

Size:

Picture Quality, Contrast and Color Saturation:

However, plasma flat panel displays are more suitable for basic home theater use than LCD. The gas cell structure within a plasma display is such that there is no light leaking between adjacent cells (or pixels). This renders plasma displays capable of displaying deeper blacks - hence better contrast and detail in television and movie scenes where lots of dark and light content is shown simultaneously.

In comparison, the nature of LCD technology - where a backlight shines through the LCD layer - means that it is hard for it to achieve true blacks (i.e.. true absence of light) as there is always some light leakage from adjacent pixels.

This does not mean that LCD panels are not suitable as TV screens; today's LCD TV sets make use of extreme high contrast panels that are capable of displaying deeper blacks, yet the latest plasma HDTV sets still have a slight edge over LCD televisions when it comes to contrast levels. The situation is somewhat similar when it comes to color saturation. Again, it is the different display structure between LCD and plasma that is the reason behind the difference between the two technologies in this respect, and though both are capable of handling color in an exceptional manner, yet plasma HDTVs still lead in this respect - producing more accurate and vibrant colors. Viewing-angle: Plasma Television sets - like their CRT TV counterpart - typically have better viewing angles than LCD televisions. The viewing angle represents how far one can sit on either side of the screen away from the center, without experiencing significant deterioration in picture quality - mainly as a result of color shifts and reduced contrast.

Though recent developments in LCD technology means that this is less of an issue - with some of the latest LCD TV sets boosting viewing angles of some 170 degrees vertically and horizontally, yet it is always best to check. The tendency - especially with cheaper sets - is that the deterioration in picture quality is more accentuated with LCD than with plasma displays.

Burn-In:

While some brands of plasma HDTVs are more prone than others to burn-in, yet in general, plasma screens are more prone to suffer permanent burn-in during their first 200 hours of use; the reason being that fresh phosphors burn more intensely as they are ignited.

Technically speaking, burn-in is the result of a damaged pixel, whose phosphors has been prematurely aged and therefore glows less intensely than those of surrounding pixels. The presence of a static image for more than half-an-hour is enough to cause temporary burn-in; temporary burn-in or image ghosting, should not be cause for alarm as normally this will wash out after several hours of use.

Worse still is the prolonged presentation of static displays, such as the use of black or gray bars to view a 4:3 picture in its original format on a wide screen display; this will result in a permanent burn-in. Once permanent burn-in occurs, the damaged phosphors cannot produce the same levels of light output as the other phosphors around them do.

In these circumstances, an LCD TV may be a better choice.

Viewing distance:

Life-time:

Now, statistics show that the average household in the US replaces their TV set every 7 years. Taking a conservative figure of 30,000 hours for either technology, this corresponds to well over 6hrs usage a day - every day - for over a period of 14 years! In other words, the flat-panel displays used in both plasma HDTVs and LCD televisions are extremely stable and reliable devices. This means that life-time should not be an issue with either display technology.

At the same time, keep in mind that there is no way to re-generate the gases in a plasma display or to repair any 'dead' pixels in an LCD display - the only option in such circumstances will be to replace the display.

Response:

Power requirements:

Price:

This contrasts heavily with LCD display technology where an estimate 30 to 40 per cent of all manufactured panels will have to be discarded as a result of defects leading to what are known as 'bad-pixels'.

Making the Choice:

It is all a question of knowing what are the advantages and limitations of each with respect to your specific needs.

Andrew Ghigo - A Telecoms/Electronics engineer by profession, with specialization in digital switching and telecoms fraud management systems. Editor and publisher of http://www.practical-home-theater-guide.com/ - a comprehensive online home theater guide to home theater systems, product reviews and home theater design.

This article is an excerpt from a series of guides appearing under the Plasma Television section of the site.

Article Source: http://EzineArticles.com/