Plasma, LCD or LED?

They may have similar price tags and looks, but there are quite a few differences between plasma and LCD screens. And while LEDs are just a variation of LCD TVs, there are differences to consider there too.

Plasma televisions

Common sizes: 42 to 60 inches

Good points

• High resolution plasma screens have very good picture quality.
• Excellent for viewing fast-flowing action. Plasma screens have virtually no motion blur, unlike some LCD screens.
• Plasmas have the best contrast, with richer, deeper blacks and vivid colours.
• Screens can be viewed from any angle without losing picture quality.
• Good picture quality in normal to low-light conditions.

Downsides

• Screens run hotter than LCDs and generally require an internal fan. Make sure this isn't too noisy.
• Uses around twice the power of an LCD and can be expensive to run.
• Screens can be very reflective in bright light.
• Using them in temperatures above 35°C can affect the life of the screen.
• Screens can be damaged by lying them flat – they need to be kept them upright at all times. So you may not be able to take your new plasma television home in the back of the car.

Much has been made of the "burn-in" effect on plasma TVs. This is where an image frozen on the screen (such as a paused DVD or game) can permanently burn its shape or colour into the screen. But most newer plasma models have anti-burn-in technology (much like a screensaver) which has minimised this effect. It still pays to ensure you don't pause anything for too long though.

LCD (liquid crystal display) televisions

Common sizes: 17 to 55 inches

Unlike plasma screens, LCD panels need backlighting to light up the pixels that make the picture. Standard LCD TVs use lamps called cold-cathode fluorescent lights (CCFLs). LED TVs (see below) use light emitting diodes for backlighting.

Good points:

• Very good picture quality.
• Images tend to be brighter and screens less reflective than plasma TVs, making them a better choice for watching in bright rooms or in sunlight.
• Use less power than plasmas.
• Lighter in weight.
• Run no risk of "burn-in" on the screen.

Downsides:

• Limited viewing angle – the picture loses brightness and colour intensity when viewed from the sides.
• Contrast is not usually as good as with a plasma screen, and blacks aren’t as deep. But they're getting better.
• More prone to suffer motion blur during fast action or sports scenes than plasma. This isn't as big a problem as it used to be, and on some of the latest sets motion blur can be barely detectable.

LED (light emitting diodes) televisions

Common size: 32 to 60 inches

Despite all the marketing hype surrounding LED TVs, they are not a different “type” of TV technology. An LED TV is simply an LCD panel that uses different backlighting. Standard LCD TVs use lamps called cold-cathode fluorescent lights (CCFLs). LED TVs use light emitting diodes (LEDs) for backlighting.

The higher price tag and newer technology of LEDs doesn’t necessarily mean a better picture. Our recent tests found some LED models ranked at the top of the table while others were near the bottom, beaten by standard LCD models.

Good points:

• Much thinner and lighter than standard LCD models.
• Generally more energy efficient than standard LCD models and much more efficient than plasmas.
• Most have very good picture quality and some are superior to standard LCD models.
• Screens are not reflective.
• Very little risk of burn-in of static images compared with plasmas.

Downsides:

• Generally more expensive than standard LCDs of the same size.
• Like standard LCDs, images can dim as you angle away from the centre of the screen.
• Have the same risk of motion blur as standard LCDs and usually more than plasmas.
• Because of their thin profile, and therefore the thinness of their speakers, some (but not all) can have very poor sound quality.

Odd spot

LCD screens are used on aircraft, but not because they're cheaper or easier to install. Plasma TVs use gases to work, and these gases are affected by the lower air pressure at higher altitudes, causing an irritating buzzing sound. LCDs aren't affected by any change in altitude. So if you're looking for a TV in Arthur's Pass or any other location above around 2000 metres, an LCD is the best bet.