|
All The Plasma
& LCD
TV Features Explained.
Firstly here is a fairly comprehensive list
of all the technical specifications that you might come across and what
they mean
High-definition
television (HDTV)
HDTV is a new system that
transmits a
TV signal with roughly twice the standard picture resolution as normal
standard definition telly. Sky (satellite) and Telewest (cable)
and the BBC (terrestrial)
operate HDTV channels. To watch some you need a subscription to watch
the BBC you just need to be able to receive the signal and
have an 'HD ready' TV. However, not everything on the
dedicated HD channels is actually recorded in HD. More programmes are
being recorded in HD all the time but content can be a bit thin on the
ground.
LED TV
Light emitting diode. A type of LCD TV but
it uses LEDs for backlighting instead of flourescent lights. This makes
it more energy efficient. Picture comparisons with regular LCD is
arguable because of the wide range of quality in LED TVs. There are
great ones and NOT so great examples.
Contrast
Ratio
The higher the number the greater the
difference between the brightest and darkest pixels. The greater the
difference the greater the potential for higher image quality.
Pixel
Resolution
The number of pixels left to right
and
top to bottom. Generally speaking a higher number offers the potential
for a higher quality picture.
Brightness
cd/m2
Like contrast the greater the potential brightness the greater the
potential for a higher quality image.
Audio
power output (RMS)
The higher the figure the
louder the
output (usually) before distortion occurs.
HD
ready
'HD ready' is a labelling scheme introduced by the TV manufacturers'
organisation, the European Industry Association for Information Systems
(EICTA). The label means the TV has the minimum screen resolution (at
least 1280x720) and digital sockets (HDMI or DVI) to receive and
display an HD picture.
plasma
A plasma display is an array of tiny gas cells sandwiched between two
sheets of glass. Each cell acts like a mini fluorescent tube, emitting
ultraviolet light which then strikes red, green and blue spots on the
screen. These spots glow to build a picture.
Native/screen
resolution
This is the number of pixels or lines displayed on the screen.
Expressed as width x height.
Aspect
Ratio
The shape of the screen (width x height). The vast majority of TVs are
now wide-screen with an aspect ratio of 16:9. Older TVs and some
portables have an aspect ratio of 4:3. Digital TV is broadcast in a
widescreen format.
Auto-Format
Switching
It's a good idea to choose a widescreen TV that automatically alters
how different broadcasts are displayed – for example, showing
standard (4:3) broadcasts with black bands on either side so the images
aren't stretched out of proportion. Most widescreen TVs will do this.
Picture enhancement features
Be
wary of these digital effects,
designed to make pictures sharper and movement smoother. Our tests show
they sometimes degrade picture quality.
Text
and digital text
With a set-top box or integrated digital TV, you can access the digital
text services available on some digital channels. These look like
internet pages, and some let you watch an inset of the TV picture at
the same time.
Picture in picture
(PIP)
Picture-in-picture displays a small image in the corner of the screen
while you watch the main image. Some TVs let you watch another
broadcast channel in this way – so you can check the progress
of a match, say.
RF input
This is the socket for your aerial and allows the broadcast signal to
be received by your tuner.
Scart
with RGB
Scarts are the best way to connect equipment like DVD players and VCRs
to your TV. Most TVs now come with at least two Scart sockets. If you
need more, you can buy a Scart switching box for £10 or so to
expand your TV's capacity.
For the best picture, look for Scarts that support the high-standard
RGB signal. This splits the video signal into its red, blue and green
components to give an improved picture.
Video
and S-Video
If you're short of Scart inputs composite video and s-video can provide
an alternative. S-Video signals are split into colour and brightness
but are slightly inferior to Scart RGB.
Composite
video
Both let you plug other AV equipment, such as camcorders and games
consoles, directly into your TV.
HDMI
input
If you're interested in HD this is the high-capacity input for
high-definition video and audio signals. Two HDMI sockets mean you
could plug in both an HD set-top box and an HD DVD player.
DVI
input
This is the standard digital input used for high definition video.
Unlike HDMI it cannot carry audio signals.
VGA
input
VGA input to connect your PC
A VGA input lets you connect your PC - effectively turning your TV into
a PC monitor. Digital DVI sockets provide an alternative but in our
tests VGA looked better on the screen. DVI can over enhance the
picture, making it too sharp.
Component
video input
This is a high quality video input made up of three sockets coloured
red, green and blue. Also known as YPbPr, it splits the video signal
into three separate parts for an improved picture.
However, component connections are still not widely used on AV
equipment and unlike Scart sockets they do not carry the widescreen
switching signal.
Phono sockets
These red and white sockets allow you to connect your TV to a stereo
amplifier - useful if the built-in speakers aren't quite up to the job.
Surround sound
Some TVs come with an extra set of speakers you place away from the set
to create surround sound. Many other TVs have 'virtual' surround sound:
they mimic the effect using the two main speakers, but this is usually
disappointing.
Optical output
If you want to connect your TV
directly to a surround sound system there are two types of digital
connections - coaxial (wire) and optical (fibre optic). Make sure your
surround sound system input matches the input on your TV.
|
All
About LCD, Plasma
& Other Screens.
|