Could you elaborate on plasma versus LCD TVs? My old telly has just given up the ghost and I don't really know the difference between the two. Fergus M Crossen
Both plasma and LCD TVs are attempts to solve the same problem: how do you make a big, flat screen without forcing a very large and very heavy bit of glass - a cathode ray tube - into an unnatural shape? Of course, both solutions have their own problems.
Plasma screens work by lighting up tiny cells of rare gases (xenon and neon) sandwiched between two plates of glass, so it is fairly straightforward to make large screens. These screens are very bright and have good contrast with deep blacks. They also have wide viewing angles, so you still get a good view from the side.
LCD screens use columns of liquid crystal molecules controlled by a matrix of transistors (in TFT or thin-film transistor designs). Some of these transistors are likely to be defective, which leads to dead pixels, and the larger the screen, the harder it is to avoid them. LCD screens are lit from behind, so they are not as bright or as contrasty as plasma screens, and may look less bright if you are off to one side. Also, they don't react as quickly as plasma screens, and may smear fast action.
However, LCD screens have made dramatic progress during two decades of laptop PC development, and these problems have largely been overcome.
LCD screens also have some useful advantages over plasma screens. They are thinner, lighter and more robust, which makes them much easier to move around. For those with ecological concerns, LCDs use little power, whereas plasma screens use lots. Further, an LCD should last roughly twice as long as a plasma screen, which may have a "half life" of only 30,000 to 40,000 hours. (The "half life" is when the screen has degraded to half its brightness, and you may well throw it away.)
As always, different buyers value different features. If you want a really big wall-mounted screen and money is no object, go for plasma. If you want a small or medium-sized screen that you can move around, go for LCD. Either way, look for a High Definition Multimedia Interface (HDMI) and an "HD ready" logo, so you will be ready for high-definition TV.
