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first pocket-size
3
colour television set had been developed. It was stated that a
liquid-crystal display
4
was used similar to those on calculators and watches and
that it weighed less than a pound.
A few years ago it became evident that the next major advance for TV
would be digital television. In a digital system the usual continuous signal is
replaced by a digital code containing detailed information on brightness, colour,
etc. A digital TV set hangs on the wall like a picture. Essentially, it is a
minicomputer with a visual display. Once a week
5
you put the programs you
like into the memory, and the TV set will automatically switch on the desired
channel at the right time. You can watch several programs simultaneously on
miniscreens and then produce one of them in full format. Also, the TV set can
automatically video-record the programs when you are absent or occupied.
By the end of 1980s television has moved to a new and the most
important stage in its development since the appearance of colour television.
Technically it is called high-definition television (HDTV)
6
or Hi-Vision. This is
the much higher resolution television
7
of the 21st century. This revolution was
started by Japanese manufacturers when they developed a new video system
with a picture resembling a wide-screen film more than traditional television.
The new system increases the screen's width-to-height ratio
8
(16:9). The result is
a picture several times sharper than in the existing TV sets. Besides, recent
developments in plasma display panel technology
9
make HDTV commercially
practicable. The plasma display makes it possible to produce a large, bright,
colour, flat TV screen so thin and light that it can also be hung on a wall like a
framed picture. The engineering problem that has existed almost since the first
days of television may be solved now.
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