What’s the difference between DTV and HDTV?
So what do I need to watch HDTV at home?
Types of TV Resolution
Types of SDTV and HDTV Displays
Common TV Connections
Q. Is DTV and HDTV the same? – A. HDTV is a segment of DTV
DTV (Digital Television) broadcasts include SDTV (standard definition), EDTV
(enhanced definition) and HDTV (high definition). Digital TV just means the image has
been digitized and is no longer being sent by analog means. The broadcast resolution
determines the picture quality.
Current analog standard TV’s will display DTV with a converter box but cannot
show HDTV because the TV resolution is too low.
Aspect ratio - Standard television has a 4:3 aspect ratio -- it is four units wide by
three units high. HDTV has a 16:9 aspect ratio, more like a movie screen.
Resolution - The lowest standard resolution (SDTV) will be about the same as
analog TV. The highest HDTV resolution is 1920 x 1080 pixels. HDTV can display
about ten times as many pixels as an analog TV set.
Frame rate - A set's frame rate describes how many times it creates a complete
picture on the screen every second. Common terms are interlaced and progressive.
The lowest quality digital format is about the same as the highest quality an analog
TV can display.
HDTV is High Definition TV
HDTV is available “free (over the air)” or via cable,
satellite or other services
Better quality picture, more information
Higher Resolution than SDTV
A High Definition TV
An HDTV signal from a provider or HD disk player
An HDTV tuner/display screen
Over the Air or
Cable Service or
HDTV has higher resolution than conventional TV
Conventional TV = 480i
▪ 480 vertical resolution x 720 pix/line
▪ 30 frames per second
HDTV resolutions are most
commonly 1080i and 720p
1080i = 1080 vertical res x 1920
720p = 720 vertical res x 1280
pix/line, up to 60fps
Interlaced screens produce their Early televisions were unable to
images by displaying every other line refresh at high speeds and
of resolution from top to bottom were limited to lower frame
rates which could cause flicker.
Interlacing helped reduce this
effect by splitting the frames
into odd and even rows. TV’s
will project these images odd
lines first and then even lines.
When the image is moving the
lines offset each other resulting
in smoother video.
Interlacing is still used today by
all TV analog broadcasts and
many cable systems.
The major disadvantage of
interlaced images is a reduction
in vertical display resolution.
Progressive scan screens display every
line from top to bottom
Progressive scan displays all of the
lines of each frame. By
progressively showing each frame
on screen every 60th of a second
rather than interlacing the image
with alternate lines every 30th of a
second. The result is a smoother,
more detailed image on screen.
Advantages of Progressive Scan Progressive scan (1080p) is now
Higher vertical resolution
used on HDTV with Blu-Ray
Less artifacts or ‘Twitter’ (flicker)
players and select satellite
Better picture quality with higher
Better looking still images
Until recently TV resolution didn’t matter much. The resolution on most TV sets before the
introduction of DTV was pretty much the same. But with the introduction of DTV that has all
changed. The chart below shows some of the different TV resolutions with HDTV starting
at 720i (1280x720 interlaced). The higher the number the higher the resolution…the
crisper the picture.
Name Resolution Scanning Aspect Ratio
480i 640 x 480 Interlaced 4:3 (1.33) Conventional TV
480p 640 x 480 Progressive 4:3 (1.33)
720i 1280 x 720 Interlaced 16:9 (1.78)
720p 1280 x 720 Progressive 16:9 (1.78)
1080i 1920 x 1080 Interlaced 16:9 (1.78)
1080p 1920 x 1080 Progressive 16:9 (1.78)
1080p is the highest resolution non-interlaced picture available.
Resulting in the best HDTV picture currently on the market.
Wide viewing angles
Capable of producing
No danger of burn-in
A vacuum tube in which a hot cathode emits electrons that
are accelerated as a beam through a relatively high
voltage anode, further focused or deflected electro
statically or electromagnetically, and allowed to fall
on a phosphorescent screen.
Slim design and
Wide viewing angles
Liquid Crystal Displays sandwich
a layer of crystals between
polarized glass and use
Super Slim design and
Contains no mercury or
Low power consumption
40% less power used than
non LED LCD TV’s
Liquid Crystal Displays sandwich a layer of
crystals between polarized glass and
use an external LED backlight
• Intense colors
– Can display up to 68
• Slim design
– Sometimes no more than
4 or 5” thick
– Place them anywhere
• Great contrast ratios
• Wide viewing angles
• Good energy efficiency
Display is made of thousands of
tiny, glass, plasma gas filled
chambers that glow
Space saving design
But still larger
Very good energy
TV signals are sent to miniature
Red, Green and Blue LCD
chips, then illuminated with
an ultra-high intensity lamp
Space saving design
Impressive black levels,
contrast ratio and picture
No alignment needed
Very good energy
Digital Light Processing TV’s use
millions of tiny mirrors tuned to be
either ON or OFF thousands of
times a second. Each mirror acts as
a pixel; colors are created by
passing a color wheel in front of the
light source for each mirror
Coaxial RF cable can be used to connect
antennas, cable boxes, VCRs, TVs, DVD
players, DVD recorders and DVRs. Coaxial
RF cable carries video and stereo audio
signals on one cable. It is the lowest quality
cable for carrying audio and video signals
and should only be used when connecting to
a TV that has no other inputs
Composite cables plug into the composite
video jacks found on many kinds of A/V
components, including DVD players, VCRs,
DVD recorders, A/V receivers, and DVRs.
They are better to use than coaxial RF cable,
but are still the 2nd lowest quality. These jacks
are often yellow, and are attached to red and
white stereo audio jacks. These connectors
are found on virtually every component in a
home TV set up, and the audio jacks are
commonly used with other video cables.
S-Video cables feature round, 4-pin
connectors, and transmit the chrominance
(color) and luminance (brightness) of a video
signal separately. As a result, they provide better
color accuracy and detail than either RF or
composite connections do. Most new TVs and
many DVD recorders and DVRs include S-
Video. A common home set up is to use S-Video
and RCA audio to connect a DVD Recorder or
DVR to a TV or A/V Receiver.
Component video cable , found on most DVD
players and recorders and some DVRs, deliver
better detail and color accuracy than you get with
RF coax, composite, or S-video. They do this by
splitting the video signal into three parts, with each
part transmitted via its own cable. Unlike the other
three types of connections, component video is
capable of passing high-definition and
progressive-scan video signals. In order to use
this cable with a DVD Recorder or DVR you must
have component inputs on your TV.
DVI stands for (D)igital (V)ideo (I)nterface. DVI is a popular form of video interface
technology made to maximize the quality of flat panel LCD monitors and modern video
DVI cables are becoming increasingly popular with video card manufacturers, and
most cards nowadays include both a VGA and a DVI output port.
In addition to being used as the standard computer interface, the DVI standard was, for
a short while, the digital transfer method of choice for HDTV, EDTV, Plasma Display,
and other ultra-high-end video displays for TV, movies, and DVDs. The digital market is
now swinging towards the HDMI interface for high-definition media delivery, and DVI is
being again constrained to the computer market. DVI does not support audio
Used to connect Hi-Def equipment like DVD players,
HDTV tuners, AV receivers and HDTVs to deliver
crystal-clear, all-digital, high-definition video and multi-
channel audio in one cable. HDMI can carry standard-
definition and high-definition digital video signals.
HDMI is also capable of carrying digital audio