Seeing is Believing
revolution is being televised and in some parts of the country
it can come to you tonight.
O. Roberts, Jr., Sharp Electronics
The Federal Communication
Commission (FCC) has begun the digital revolution for television.
Digital Television (DTV) is an exciting new broadcast standard
that provides vastly improved picture and sound quality when compared
to the current NTSC broadcast standard. With DTV, viewers can
see images up to six times the resolution of their current TV’s.
The received DTV image can be viewed without double image ghosts
or snow frequently associated with some of today’s air/cable broadcasts.
And wide screen movies can be displayed just like in the movie
theater accompanied by a Dolby Digital (6-channel audio) soundtrack.
The advent of DTV is one of the many advances in our industry
that is an example of digital technology providing a higher quality
product to today’s consumer.
Today, there are
18 approved DTV transmission formats.
The 1080i transmission
(1,080 x 1,920 lines, interlaced) represents the highest level
of digital broadcast. In the digital world, resolution is expressed
in pixels per second. Also, there are two scanning methods used
to receive the signal—interlaced scanning and progressive scanning.
An interlaced picture
is constructed by interlacing two fields of video information
to form one frame, as in today’s analog televisions. Wow! Is this
complicated enough? In other words, two dots have a relay race
across the picture tube of your television. One dot races across
the set in 1/60 of a second. The first dot "tags" the second dot
to race back in 1/60 of a second. When both dots have finished
the race, you receive a full video frame. With progressive scanning,
the picture is constructed of a single frame of video that encompasses
all of the video information. Progressive scanning is done just
like today’s PC monitors. When comparing resolution at any of
the transmission levels, the difference is expressed in pixels
million pixels per 1/60 second.
480p…1/2 million pixels per 1/60 second.
480i…1/4 million pixels per 1/60 second.
The first digital broadcasts
were targeted for broadcast in November, 1998, in ten major U.S.
cities: Atlanta, Boston, Chicago, Dallas, Detroit, Los Angeles,
New York, Philadelphia, San Francisco, and Washington, D.C. (Unfortunately,
Chicago and New York experienced delays and moved further down
the schedule.) These cities, and the rest of the country, will
experience a gradual transition from the current analog broadcasts
to digital broadcasts over the next ten years. Because the digital
broadcast is over-the-air, consumers will be able to pick up the
signal with an in-home antenna, or in the same manner they currently
use. Also, cable and satellite companies will be able to transmit
a digital signal. Subscription rates and types of programming
will vary. However, access to a digital signal will be relatively
easy once a broadcast begins in your area.
Do I need to wait
to buy a digital television?
No. When your town/city
starts to broadcast a digital signal, the television components
in your house will have to be updated. That means you will need
a decoder to decode the digital transmission to receive a digital
signal. The local broadcaster in your area may choose to broadcast
any one of the 18 approved signals or may even choose to utilize
multiple transmission broadcasts. But don’t worry about your current
television set becoming obsolete. If you would like to see a digital
broadcast, purchase a digital decoder and view the programs you
desire. And remember the FCC will continue to offer analog broadcast
space for television programming at least until the year 2006.
So, you will be able to watch all your favorite shows just the
way you are now, or you can choose to update to digital technology
when you desire.
One aspect of digital
television is the ability to receive the signal. The other important
aspect of digital television will be the ability to receive audio
and video signals at a far higher quality than ever before. The
digital television signal has two different formats: HDTV
(High Definition Television) and SDTV (Standard Definition
Television). HDTV transmissions are at 1080i or 720p. SDTV broadcasts
are any of the other digital transmission rates. HDTV broadcasts
are at the top end of the digital television spectrum. These broadcasts
will have the best sound quality, the ability to broadcast in
a wide screen format, and the best picture quality. The picture
quality of HDTV is exceptional. The colors are brilliant. The
depth of the image is almost three-dimensional. Many people viewing
HDTV for the first time have commented that, "it’s almost like
being there." In order to experience the high-quality picture
of HDTV, you will need more than a digital decoder. You will need
a television monitor/receiver capable of receiving video information
at levels significantly higher than most of today’s current line-up
of NTSC television sets. Sharp showed prototypes of these models
at the Consumer Electronics Show. Remember, the resolution of
HDTV will be six times the resolution of today’s NTSC televisions.
Therefore, part of this digital revolution will be for manufacturers
to produce television components capable of producing the high
quality video images that will be broadcast.
The reaction to Sharp’s
proposed digital television products has been extremely favorable.
It is guaranteed that the DTV revolution will be an exciting consumer
event. It will be a technological marvel and a visual showcase
that will provide the viewer with a more accurate, more consistent,
more enjoyable way of receiving video information than ever before.
Indeed, the digital television revolution will be televised. It
will be LIVE.
Copyright 1998 Sharp Electronics, Inc. Used with permission.