Liquid-Crystal Display: A High-Tech Device On the Move
TECHNOLOGY creeps up on kitten's feet. Sometimes we miss the important turning points. About eight years after we got our first color TV, my father bought me a digital watch. The watch was cool. It had a small liquid-crystal display (LCD) that replaced the dial with a numerical readout of the time and date and so forth. But the color TV impressed me more.
''Batman'' in color? Zowie!
It turns out the LCD was a more important technological breakthrough. Today, it threatens to make television's picture-tube technology obsolete. LCDs are showing up in everything from camcorders to the notebook computer I'm using to write this column. One day you might hang an LCD television on the wall, just like a bulky picture frame.
''We just think LCD is the electronic paper of the future,'' says Bob Garbutt, general manager for Sharp Electronics' LCD products group.
LCDs have several advantages. They use weak electric fields to change the optical properties of the liquid crystal. The field can make the crystal turn from light to dark or, in more advanced displays, into various colors. This technology makes LCDs much lighter and more compact than a television's picture tube, which needs a glass-contained vacuum with an electron gun at the back to create a picture.
LCDs are also easier to look at. Each dot on the screen is addressed in the display while picture tubes scan through entire rows of dots. Traditional computer monitors work the same way.
The trouble with the LCD is that it's far more expensive than picture-tube technology. Notebook-computer users are willing to pay this price because it means they can carry their machines anywhere. Television owners, who typically keep their set in one place, aren't going to spend hundreds of dollars extra for the newer technology. Even many notebook-computer users balk at the most advanced LCDs, known as active-matrix displays. That's why they opt for the passive-matrix screens, which cost about $800 less. Happily, the economics are changing.
Since 1990, top LCD companies in Japan have spent more than $5 billion to improve technology. Sharp, which has more than two-thirds of the active-matrix market, is opening a new factory in Japan this summer, doubling the company's capacity. South Korean companies have spent $2 billion trying to muscle in on the market.
The result is that prices have fallen sharply. Dataquest analyst Jack Roberts expects the cost of active-matrix screens to fall another 20 percent this year. And screens are getting bigger. If you've ever compared an 8.4-inch notebook display with the newest 10.4-inch screens, you'll be amazed how much more readable the larger screens are. Watch for even larger displays -- 11.3 inches -- to start showing up in notebooks later this year.
Resolution is increasing. Instead of today's standard 640-by-480 dots (or pixels) on a screen, notebooks will start sporting 800-by-600 dots. The more pixels, the finer the image. Companies have also boosted brightness and contrast while cutting power consumption. This month Sharp will show off an LCD screen that uses less than a watt of power, down from 3.3 watts. So, future notebooks will work longer hours on smaller batteries.
LCDs will likely show up next on personal digital assistants, those computing devices small enough to hold in one hand. Today's versions sport black-and-white screens; tomorrow's will be full color. Huge projection TVs are also incorporating LCDs.
Conventional TVs may be the last holdouts, because the current technology is so cheap. And that's OK. Even if I can hang the set over the mantlepiece, ''Batman'' reruns just don't pack the punch they once did.
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