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Buying a new television set

by Tod Maffin
It used to be so easy to buy a television set. You'd buy it, plug it in, and it would work. Not any more -- today, you need to know about resolution, technology, and all sorts of other geeky things. Here's a primer.

TECHNOLOGY

TVs used to use just one kind of technology: the aging Cathode Ray Tube. Which still works fine, even though the technology is more than a hundred years old now. Today, TVs come in four more flavours: Plasma, LCD, LCOS, and DLP:

  • Plasma got a bad rap some years ago, but the newer screens last about 60,000 hours. That's 24 years of TV watching, assuming you're glued to the set 7 hours a day. Plasma usually has the darkest darks, but the screen is reflective, so if you'll be watching where there's lots of sunlight, Plasma may not be your best option. Also, if you live really high, the screen won't work because plasma is literally a gas and at high-altitudes... the gas converts to, uh... Look, I'm the technology reporter, not the science guy.
  • LCD is the same technology used in computer laptop screens. It's good in places where there lots of sun because there's no glare off the screen, and generally uses about 20% less power and weighs less than a Plasma TV.
  • LCOS is like LCD but the material used is silicon. Which, in theory, could last a hundred years. For you, it just means bragging rights.
  • Finally, DLP televisions. They have thousands and thousands of tiny little mirrors reflecting the image to the screen. This gives a nice bright picture with deep darks. Like a Plasma screen. But they're cheaper. Future Shop sells a 52-inch DLP screen for about $1500 bucks.

RESOLUTION
You didn't have to think much about resolution for your regular TV because it always came in only one option. Television sets display an image by carving it into hundreds of horizontal lines that go across the screen. Think of it like an Etch-a-Sketch. The more lines you use to draw a bunny, the more detailed that bunny will look.

  • Your standard television -- the one probably in your house today -- can draw 480 lines across to make up the image. First it draws every OTHER line, then it goes back and fills in the remaining half. This is called an Interlaced Signal because the lines interlace with each other as they're being drawn -- first the odd, then the even. These 480 interlaced lines is what TV nerds call Standard Definition.
  • The next step up is ED: Enhanced Display. The TV salespeople love ED because it looks better and is cheaper, which makes for an easier sale. Enhanced Display also spits out 480 lines. So why even bother if it uses the same number as your cheap existing box? Because ED televisions draw those lines all in one fell swoop. Not interlaced with every other line. That's called Progressive and makes the image sharper.
  • Finally, there's the cool kid: HD. High-Definition. And here too you have a choice. Either 1080 interlaced lines or 720 progressive lines. And I know, why go with 720 lines when you can have more than a thousand? Because to some people 720 lines look better because they're displayed progressively. You'll want to go to the store and see which one YOUR eyeball favours.

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