If you’re shopping for a big screen TV, there’s advice all over the place on which to get. My blog is no exception! This is coming purely from a home theater point of view. If you don’t care about colors, viewing angles, or size (say, if you plan to use it to watch Bloomberg Television), my conclusions might not be what you’re looking for. However, if you want to watch Lord of the Rings and have your eyeballs melt… then read on!
What are LCD and Plasma Screens?
An LCD screen is made up of liquid crystal pixels pushed between glass plates. Current goes through the pixels, and a controlled picture is created. This is how a digital wristwatch works, basically, only with more colors and smaller pixels. It’s important to note that the pixels are backlit-they don’t light up on their own.
A plasma screen, on the other hand, uses millions of little cells filled with neon and xenon gas. When electricity zaps these cells, the gas turns into a plasma (hence the name). Each cell is coated in phosphors (red, green or blue), which fluoresces when the plasma gets charged. Think of a plasma screen as a sheet with millions of tiny, tiny fluorescent light bulbs, because that’s basically what it is.
Plasma: None More Black
One big difference a lot of people find between LCD and plasma is the deepness of blacks. Plasma screens get a deep, true black, because it’s made up of tiny lights. Turn the lights off, and you get the absence of light, which is as black as it gets! LCD screens have a constant backlight, however; LCD blackness is thus achieved by setting the pixel to block as much light as possible. There’s always a little leakage, though, so you never get true black, especially at certain angles.
This viewing angle is another big issue with LCD screens. If you’re looking at it from the wrong angle, the colors distort and the black gets even lighter. This has to do with the polarity-shifting mechanism of LCD technology. I’m told they’re getting better at this, but it’s still annoying, in my opinion. My new laptop is LCD, and while it’s bright and crisp, the top and bottom of the screen are usually a little discolored compared to the middle, because I’m viewing the top and bottom at the wrong angle. I can turn the screen to fix this, but then the middle’s at the wrong angle.
Plasma TVs are also usually bigger. Most LCDs top out at about 50″, barring a couple new (and costly) 70-inch models, whereas larger plasmas are easy to find.
LCD: More Pixels, Less Juice
Why would anyone go with LCD TVs? Well, for one thing, they’re cheaper than similarly-sized plasma models most of the time, and they’re getting even cheaper by the day. LCDs also usually have a much higher resolution. More pixels can be better!
There’s also the issue of burn-in. The phosphors used in plasma screens wear out over time (a long time- 30k to 60k hours). Ever seen an old arcade machine, where the title screen was still visible even when the picture changed? Same deal. It’s usually not that bad these days, of course, since most pictures move around more than a Galaga high-score list, but any plasma screen’s days are numbered. LCD screens die, too, but usually much later on in their lives, and there’s no risk of ugly, mucky burn-in. If you care about power consumption, and you should, it’s worth noting that LCD uses far less power (as much as 30 percent less than plasma). That adds up to a lot of clams.
So, which one should I get?
If you’re talking about a TV screen, and not a computer monitor, I’d suggest plasma. The viewing angle issue alone should seal the deal to anyone who plans to put the TV in a family’s living room, and the lack of true black is, in my experience, not very cool. LCDs tend to be lighter and cheaper, though, and are fine for a lot of smaller applications like computers. Cheaper does go a long way, too; that’s extra money to spend on speakers, DVDs, or a whole lotta beer. Not to mention the lower power draw, which (in this age of utility bills gone mad) is a gift that keeps on giving!