Tuner

Each has benefits and disadvantages and so each is more appropriate in specific circumstances.

Historically, the LCD vs plasma HDTV choice has been fairly simple. If you wanted a flat-screen that was about 40in or bigger, you had to choose plasma, otherwise you should choose LCD. However, as LCD technology improves, LCD HDTVs are getting bigger and most of the major manufacturers expect the number of LCDs they produce to grow steadily over the next few years while the number of plasmas will decrease. However, if you're looking for a flatscreen TV today, plasma still has a lot to offer.

To understand the LCD vs plasma HDTV question, we need to look at the way the two technologies work.

LCD

LCD HDTVs work by shining a light behind an LCD panel made up of a fixed number of pixels. Each pixel is either red, blue or green and is switched on or off when a voltage is applied to it. When voltage is applied to a pixel, it is switched off, meaning that light can't shine through it.

The main advantage of LCD vs plasma HDTV is that LCD panels don't suffer from what's called burn-in. This is a feature of plasma TVs where they are used to watch TV stations with logos permanently displayed on-screen or where they are used for video gaming with games that have static images

such as a cockpit on flight simulators. The image literally 'burns-in' the screen meaning that even when the image is not present you can still see a faint trace of it on screen. So for video gamers in particular, LCD is a better choice than plasma.

Plasma

Plasma HDTVs have over a million chambers which house one or a combination of gasses. When a voltage is applied to one of these chambers the gas ionizes and emits ultra-violet light. This light strikes red, green or plue phophors coated on the inside of the chamber and a pixel emits this color light.

Plasma HDTVs tend to have better contrast than LCDs because, even when a pixel on an LCD panel is switched off it doesn't block all the light coming through and therefore the pixel isn't completely black. Plasma HDTVs also tend to have a wider viewing angle than LCDs, as on LCD HDTVs the contrast and colour of the image can change when the screen is viewed from different angles.

LCD vs Plasma HDTV conclusion

Technology is changing rapidly, but for now (July 2004) it's still true to say that at sizes of 40in and above, plasma offers a less-expensive and generally better solution. For screen-sizes less than 40in LCD is better. However, as LCD technology improves and prices fall, this will change.
About the Author

Kenny Hemphill is the editor and publisher of The HDTV Tuner - a guide to the kit, the technology and the programming on HDTV.