LCD TV Buying Guide

Plasma VS. LCD

Which is better, Plasma or LCD? It depends. This is a complicated and detailed topic between two technologies that process and display incoming video or computer input entirely differently. Both technologies are advancing rapidly and both are bringing down costs and end user prices at the same time. The collision between the two will take place in the 40" (diagonal) range of monitor/TV in the very near future.

following are some advantages of each technology and how those advantages relate to a purchaser of either - for different uses:

1) SCREEN BURN-IN
LCD has almost no static image screen burn-in factors to consider. LCD (liquid crystal diode) technology uses essentially a fluorescent backlight to send light through its pixel design, which contains liquid crystal molecules and polarizing substrate to give form to light and color. The "liquid" crystal in an LCD is actually used in its solid state.
Plasma technology does have static image screen burn-in factors to consider. Static images will begin to "burn-in" the image displayed in a short period of time, approximately 15 minutes in some cases. Though the "burn-in" can generally be "washed" out using gray images or continual full color ranges over several hours, burn-in is a significant factor and hindrance to the plasma technology.

Advantage: LCD For applications such as airport displays with flight information, or retail static sales images displaying the same information or pictures on a continual basis - an LCD monitor will be the superior choice.

2) CONTRAST
Plasma technology has come a long way in developing higher contrast images. Plavo now boasts that its plasma displays have a 3000:1 contrast ratio. Plasma technology simply blocks the power emitted (through complicated internal algorithms) to specific pixels in order to form dark or black pixels. While sometimes hurting gray scaling, this technique does produce dark blacks.

LCD by contrast has to increase the power voltage to make pixels darker. Thus, the higher the voltage surging into and through the pixel, the darker the LCD pixel. Though there are improvements in LCD contrast and black level, even the best producers of LCD technology such as Sharp can only produce a contrast of between 500:1 to 700:1.

Advantage: Plasma For scenes with lots of dark and light shown simultaneously from film originated material, DVD content, or action in games relying on lots of black content, plasma will outperform.

3) LONGEVITY
LCD manufacturers claim figures between 50,000 and 75,000 hours for LCD monitors/TVs. An LCD can last as long as the backlight (and backlight bulbs can actually be changed out). This is because the light is passing through a prism effect of the liquid crystal to produce the light and color. It's a substrate so there is nothing to effectively burn out.

Plasma by contrast uses a small electric pulse for each pixel to excite the rare natural gases argon, neon and xenon (phosphors) used to produce the color information and light. As electrons excite the phosphors oxygen atoms dissipate. These rare gases actually have a life and fade over time. Manufacturers of plasma place a time stamp of 25,000 to 30,000 hours on the life of these phosphors and thus, the display itself. They cannot be replaced. There is no phenomenon of "pumping" new gases into a plasma display.

Advantage: LCD by double or more. Again, for applications requiring industrial/commercial use such as 24/7 storefront displays, LCD is superior for longer use, without regard to picture requirements.

4) COLOR SATURATION

Color information is more specifically realized and accurately reproduced in plasma because all of the information needed to manufacture every color in the spectrum is contained in each pixel cell. Each pixel contains a blue, green, and red element to produce accurate color detailing. The saturation resulting from the plasma pixel design produces the most vibrant colors of any type of display in my opinion. Chromaticity coordinates are much more accurate on good plasma panels than on LCDs.

In LCD, controlling light waves at different speeds to allow them to pass through long thin crystal molecules is a more difficult templatefor producing accuracy and vibrancy in color. Color information benefits from the smaller pixel design of most LCD monitors, but would not be as impressive as plasma at the same size pixel level.
Advantage: Plasma by a good margin. For video content especially fast moving images, plasma technology will excel. LCD is preferred when displaying a static computer image, not only because of burn-in, but because it will also produce nice smooth color with this type of setting.

5) ALTITUDE
As mentioned earlier, LCD is a backlit technology with crystal molecules deflecting light at angles to give color and definition. As such, there is nothing to pressure the unit at altitude and no real limitations. This explains the use of LCD screens as the primary viewing screen for the airlines in flight video material.
Since the plasma display element on a plasma TV is actually a glass substrate envelope containing rare natural gases, thinner air causes increased stress on the gases inside the envelope. This increases the amount of power required to run and cool the plasma which causes louder buzzing or fan noise. These problems usually start to occur at around 6500 feet.


6) VIEWING ANGLE
Plasma has always boasted a 160 degree viewing angle, which is as good as it gets. LCD has come a long way toward improving viewing angles. The substrate material on newer generation LCD's by Sharp and NEC has been improved drastically as well as increasing dynamic range. However, they did have a long way to go and there is still a noticeable difference between the two technologies when viewing from angles.

Advantage: Plasma Each cell is lit on its own allowing for superb brightness through every pixel. No backlit device (like LCD) will match up well from the angles with plasma.

7) COMPUTER USE
LCD displays static images from computer extremely effectively and with full color detail, no flicker, and no screen burn in.
Plasma is challenged with static images from computer. Though it will display them well, screen burn in is an issue as well as a "step" effect in the lower resolution panels when displaying static lettering (Powerpoint). Video images are good but there can be some flicker depending upon the manufacturer quality of the unit and the resolution being displayed. Plasma still wins out on angle viewing of course.
Advantage: LCD except at harsh angles.

8) VIDEO PLAYBACK
Plasma will get the nod here because of the excellent performance with fast moving images, high contrast levels, color saturation, and brightness.
With LCD there can be a "trailer" effect during fast pace scenes from video as the technology is much slower reacting to color changes. This results from the light prisms that must be produced from controlling voltages applied to "bend" the light. The higher the voltage applied to the crystal, the darker the image in that section of the LCD panel. This is also the reason for the lower contrast levels.

Advantage: Plasma by a good margin. For DVD, or any streaming video content, TV or HDTV - plasma will deliver non distracting, high contrast (depending on the plasma), high color saturation viewing. LCD has come a long way but is still challenged at the same size comparison while looking great at the smaller sizes.

9) PRODUCTION SIZE AND COST/PRICE
Though both panels are difficult to produce in large panels, plasma has proven the easier of the two as manufacturers have produced plasma panels in the 60" to 63" range. While these displays are still very costly, they have proven that they operate effectively and reliably.

LCD substrate material is difficult to produce in larger sizes without pixel defects. The largest LCD at this moment is a 40" commercial version by NEC. Before that Sharp stretched the LCD horizon from 20" to 22" then 30" and now is just starting to ship its new 37" diagonal widescreen panel.

Advantage: Plasma Even though costs and prices are coming down on both technologies (except the very large plasma panels), plasma still holds the lower cost and higher production capacity and thus pricing advantage. The 50" plasma panel size is extremely popular and is quickly gaining market share from the previously dominant 42" size. This trend of plasma being the lower cost and price producer will likely continue for at least 2 years.

10) VOLTAGE REQUIREMENTS
By using a type of fluorescent backlighting system for light production, LCD has much lower voltage requirements than its plasma counterpart. Plasma by contrast has the challenging requirement of powering hundreds of thousands of transparent electrodes to provide light and excite the encased phosphors of each cell.