PICTURE QUALITY LCD TV vs. Plasma TV

Updated for 2017

Reviewer: Phil Conner

CONTRAST/ BLACK LEVELS

Plasma technology has certainly achieved quite high contrast ratios, a measure of the blackest black compared to the whitest white. Many plasma display manufacturers boast a contrast ratio of 10,000:1 these days though our tests have not proven these numbers out - especially not post calibration. Panasonic has long been the leader in plasma black levels and we measure ANSI checkerboard contrast of today's Panasonic plasma at 850:1 – still extremely impressive. 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 television’s gray scaling, it does produce exceptionally black blacks – depending on the manufactured plasma display element (i.e. glass). 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 (liquid crystal diode) 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 displays consume 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 displays (like those produced by Sharp and Sony) have managed to topple the 500:1 contrast ratio barrier (post calibration). The one continual drawback here for LCD is off axis viewing, when black levels consistently drop.

"Plasma TVs still maintain a clear advantage in this category"

ADVANTAGE: Closer than a year ago, but still Plasma. LCD manufacturers have made great improvements in black levels and in many cases have managed to match the contrast ratio of plasma displays. However, Plasma TVs still maintain a clear advantage in this category due to fading blacks when viewing LCDs from off axis. In a dark room environment the user will notice the hazy effect present in blacks on LCD TVs. 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 still consistently outperform LCDs.

 

COLOR ACCURACY

In plasma displays, each pixel contains red, green, and blue elements, which work in conjunction to create billions of colors. Insofar as each pixel contains all the elements needed to produce every color in the spectrum, color information was more accurately reproduced with plasma technology than it was with other display technologies. The chromaticity coordinates were more accurate on most plasma displays. Though the color saturation resulting from the pixel design of plasma displays is remarkable, LCD technology has nearly caught plasma in gray scaling color accuracy. Plasma continues to exhibit more richness in color information and more natural coloration. Today, SMPTE color coordinates in top plasma TVs still normally outperform those in LCDs, which tend toward oversaturation.

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. LCDs however, produce a typically brighter picture. Greens sometimes look too green and reds can run a bit warm, but in a room with bright outdoor lighting, an LCD would be my choice.

ADVANTAGE: LCD

VIEWING ANGLE

"Plasma TV holds the black levels from off axis, while LCDs lose black level as the angle off increases."

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. Plasma TV holds the black levels from off axis, while LCDs lose black level intensity more as the angle off axis increases. This usually occurs after around 90 degrees.

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

ADVANTAGE: Plasma

 

DEPTH PERCEPTION

Due to a deeper pixel cell structure plasma technology again triumphs in this category. With an incoming HD signal plasma looks more three dimensional than LCD TVs. LCDs rely more on the effects of lighting for depth characterization and images at times can appear flatter.

ADVANTAGE: Plasma

 

BRIGHTNESS

LCDs have enjoyed such great success from the showroom sales floor due to the extreme levels of brightness they can achieve. As mentioned before LCDs product white naturally with untwisted crystal, while plasma TVs must use more power and effort to product white. As well, LCDs contain backlights (usually a type of flourescent tubes), the brightness is easily improvable to very high levels.

ADVANTAGE: LCD

 

SUMMARY OF PICTURE QUALITY CONSIDERATIONS LCD vs. PLASMA

As the above advantages show, plasma technology has the better picture quality in normal to low room lighting conditions and are better in 4 out of 5 picture quality categories. Plasma technology will almost without exception triumph during night time viewing. LCD televisions are great for sunroom/breakfast room type environments. Also, LCD monitors are generally better for public display such as airport signage and retail store signage due to the bright room light environment.