LCD TV Beginners Guides and Buying Tips

The Principles

At first glance, an LCD TV could easily be mistaken for a plasma display. They are both extremely shallow, just a few inches deep, and both have totally flat screens.
The similarity between the two types is only skin deep, however, and they produce their pictures in very different ways .

basic technology

While plasma sets share some characteristics with CRT TVs (see our Guide to CRT Televisions and Guide to Plasma Televisions), LCD sets do things their own way.

The technology relies on a special characteristic of liquid crystals. Although they are not liquid in the common sense of the term, they react to an electrical impulse, changing their alignment.

The way the crystals are aligned means either that light can pass through, or it is blocked out. LCD TVs use a light source at the back of the screen to shine through the LCD panel. Some pixels on the screen let light through and others do not, depending on whether or not they are receiving an electric current.

Coloured filters then do the rest, creating red, green and blue points of light in millions of combinations to make up a TV picture.

pros

• LCD TVs are very slim, measuring just a few inches in depth

• They are lighter than plasma sets (and much lighter than CRT TVs)

• They are immune to ‘screen burn’, which is an issue with plasma sets

• They use a lot less power than plasma sets

• The light source in an LCD can be easily replaced if you wear it out – although with lifespans of about 20 years for average use this shouldn’t be an issue!

• They can be used as a PC display

cons

• Contrast levels are not as good with LCD TVs as they are with CRT and plasma sets

• The ‘viewing angle’ of an LCD TV (how far to the side you can watch the screen without the picture fading) can be restrictive

• Colours can be slightly dull compared to plasma sets because of stray light in the set

• Individual pixels can stop working (they are known as ‘dead pixels’), but these are so scattered about the screen you probably won’t know they are there

• LCD TVs above 42 inches are rare and very expensive, although prices will fall

• Plasma TVs have superior response times

'HD ready' LCD sets Like plasma displays, LCD sets come into their own when you are watching high-definition images on them. The ‘HD ready’ badge means a TV is equipped to receive high-definition broadcasts. Don’t be fooled by claims of ‘high-definition compatibility’ – this can disguise the fact that a TV modifies the high-definition signal to display it, and you could lose out on the extra picture quality.

top tips for buying a lcd television

• Check out the viewing angle. Make sure the image remains watchable when viewed from off-centre

• If you want to receive high-definition programming when Sky launches it in 2006 you will need a set with a digital video input (either DVI or HDMI) and HDCP compatibility

• If use as a PC monitor appeals, you will need a set with suitable PC inputs

• Be aware that plasma sets are cheaper for larger screen sizes

• Don’t buy a TV that’s too big for your room. For a 32-inch set you should be able to sit at least six feet away, or the structure of the picture will be evident. For a 42-inch set you need at least 10 feet between you and the screen