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These
are the stereo audio jacks that let you connect your TV to your stereo or
home theatre system. Typically there are two types:
fixed, and
variable.
If you connect a TV's fixed
output to your A/V receiver, you can raise and lower the TV volume via the
receiver's volume control. If you connect the TV's
variable output to your receiver
you control the TV volume using the TV's remote.
A/V inputs (composite)
These
are the standard RCA jacks that hook up audio and video components to each
other, typically yellow (video), black (or white) and red (for your audio
left and right input). Composite video connections are not considered to
handle the best picture because they mix colour and black & white signals
together. Although composite connections provide an adequate quality
picture, a better picture quality can be often be achieved using either an
S-Video cable (good), 5-jack component video cable (better) or
HDMI connector (generally best).
Built-In Tuner
A
TV tuner is simply a device which allows you to receive channels of
television content. Video displays that lack built-in tuners require some
kind of external device that does have one in order to receive television
channels. All U.S. PRIMA models larger than 25” feature both built-in NTSC
tuners (for channels 2-125) as well as an ATSC tuner to watch newer
digital channels. Not all digital channels actually transmit full
resolution (HDTV) content. Some ATSC tuners also include QAM capabilities
for users on cable systems, allowing additional optional tuners to be
connected if necessary.
Cable
Card (DCR pod access)
In early 2006 fewer than 85,000 Cable Cards had been produced and only an
estimated 48,000 were actually installed and working in U.S. and Canadian
homes. There remain significant software and inherent pass-through
problems with various cable systems, and the second-generation adoption of
“two-way” interactive Cable Card II pods appear far less likely to meet
adoption by the industry.
Child
Lockout or V-Chip
Both of these
systems are designed to help parents limit their child's access to
inappropriate TV programs. Child Lockout allows parents to limit access to
certain channels from those without the special code.
The
V-chip allows parents to select the maturity level of the programming they
feel is appropriate for their children based on the TV Rating System. The
V-chip reads the transmitted ratings code for all programming and will
automatically deny access to programming that exceeds preset ratings
limitations.
Comb Filters
The purpose of a
comb filter is to separate a composite video signal's luminance (Y)
information from its colour (C) information. There are several ways to
perform Y/C separation and comb filters are the most common. There are
several different types including:
Analogue Comb Filter
Older
technology generally found in many low cost CRT (tube) televisions, with
limited improvement in sharpness. Sometimes referred to as a “2-line comb”
filter.
Digital Comb Filter
It
converts colour and black & white picture information to digital
information, and does a better job in processing accurate video displays.
It provides better picture sharpness with less colour artefacts and
shimmer than on analogue comb filter sets.
3-7 Line Digital Comb Filter and 3D Y/C
combs
These
types of comb filters offer refinements and more critical processing. They
provide the highest resolution (picture sharpness) and virtually eliminate
all picture artefacts such as dot crawl and shimmer. Newer models include
the latest versions of 3D Y/C processors available, and are combined with
more advanced forms of video processing.
Contrast ratio
This
is the difference from the brightest whites to the darkest blacks capable
of being displayed. For contrast ratio the greater the difference in ratio
means that the display to can show more distinctive colour details to
viewers.
omponent Video
connectors
The
next step up in performance instead of using a basic S-Video connection or
composite connections. Component cables and inputs can provide an
excellent picture with very high resolution, better colour accuracy, and
less colour bleeding. Component Video transmits the video signal in three
parts: the luminance (Y), the blue chrominance (Pb), and the red
chrominance (Pr). If you plan to use your TV with external devices such as
a progressive scan DVD player take advantage of this increased quality by
using either Component cables or HDMI. Resolution quality is still
dependent on the quality of the source (the equipment which outputs the
signal), the quality of the resolution at the source, and whether the data
is improved or limited during processing. Component video connectors have
either 3 end connectors or 5 end connectors at each end (if you include in
your count the Left and Right end connectors used to hook up the audio
portion). A set of composite connections has only three (a video, and a
left and right audio), usually in red, white (or black) and yellow.
Component connections generally provide a significant improvement in
quality, particularly with progressive scan DVD players and recorders.
CRT - (Cathode-Ray
Tube)
A
"picture tube" (CRT) is the vacuum tube which creates images when an
electron beam scans across a phosphor-coated screen. While performance can
be outstanding in premium CRT televisions, the weight and size of these
TV's has greatly been reduced demand by flat-panel models using LCD and
plasma technologies.
Digital
Focusing
Digital
focusing computer-aligned circuitry provides precise and consistent
picture performance from the moment the TV is turned on. Digital focusing
helps to maximize picture brightness with sharper corner focus, to ensure
a detailed picture across the entire screen.
Digital audio output
A
connection found on HDTV’s and HDTV tuners for sending the Dolby Digital
audio of HDTV broadcasts to an A/V receiver with Dolby Digital decoding.
The two most common types of digital output are
coaxial
and
optical.
DVI
An
older connection (prior to the wider and more recent use of HDMI) which
provides an uncompressed, encrypted, high-band width digital HD signal to
the television. No longer used on newer models, it has been replaced with
HDMI connectors for better performance and simplicity.
Edge
Correction
Delivers
a cleaner image by sharpening the edges of objects in a digital picture.
HDMI (High Definition
Multimedia Interface)
Like
the older DVI connection it typically replaces, an HDMI connection allows
for the uncompressed data transfer of video between HDMI-enabled consumer
electronics devices. A key difference between HDMI and DVI is that HDMI
transfers the video
and audio
signal. DVI only carries the video signal. Newer models feature dual (two
separate) HDMI connections. This allows the use of both a HDMI connection
to an external digital tuner (such as a digital cable set top box or
satellite receiver), plus the expansion for high-definition disc players
and recorders (such as HD-DVD or Blu-Ray disc hardware), and other HD
devices. According to the HDMI’s official Web site, the advantages of HDMI
are:
1) The highest quality video
seen and audio heard.
2) Fewer cables mean less mess and provide a confusion-free connection.
3) Automatically configures remote controls of devices connected by HDMI.
4) Automatically adjusts video content to most effective format.
5) HDMI is compatible with DVI, which means it will allow connection to
PCs.
LCD - Liquid Crystal Display
L
CDs first became popular in the early 1970s. Today, they can be found in a
variety of digital devices, including calculators, watches, flat panel and
some rear projection TVs. As the name implies, they use a gas-like
substance known as Liquid Crystals to create a display.
LCD
televisions do not produce their own light, so a light source behind the
display is also necessary; this is accomplished by using several light
sources and a "diffuser plate" to help distribute the light evenly. This
backlight must be powerful, as polarized glass and liquid crystal
materials absorb typically from 35%-55% of the light that passes through
their layers.
Menu Languages
For
multilingual households, this allows on-screen operating menus to appear
in different languages. All North American PRIMA models display in
English, Spanish, and French.
MTS (Multi-channel Television
Sound)
The
means in which stereo sound is broadcast “over-the-air” to analogue TV
channels. Various processors exist to provide stereo reception. SAP is the
secondary audio program often associated with listening to channels
individually, such as English or Spanish as optional language channels.
NTSC
TV Tuner
NTSC
is short for National Television Standards Committee. An NTSC tuner refers
to a standard analogue TV, which displays in 480i, typically for channels
2-69, and added cable channel content. It cannot receive newer digital
“over-the-air” transmissions unless it is also combined with an ATSC HDTV
tuner.
Plasma
In
a fluorescent light bulb, an electric current excites gas in a glass tube
causing the release of ultraviolet photons. These photons hit the phosphor
coating inside of a fluorescent tube, and this phosphor creates visible
light. Plasma displays use a technology similar in concept to a
fluorescent light bulb.
Plasma
is a highly ionized gas-like substance that acts as a conductor of
electricity. A plasma display is made of plasma-filled chambers, which are
layered between two wired glass panels. Images are displayed when an
electric current excites the plasma, causing ultraviolet light that
strikes the phosphors on the back of the display to highlight appropriate
colours. Unlike LCD displays there is no back light source because plasma
units produce their own light.
Picture-in-Picture (PIP)
This
technology provides a small picture of another channel (or sometimes the
image from another external video device) in the corner of your TV's
screen. You may also have the option of watching split-screen
programming, or having multiple programs shown in several boxes on the
screen.
PixelWorks DNX
(Digital Natural Expression)
A
trademark technology, Pixelworks is a leading provider of advanced IC’s
which process and optimize video in several models of the new Prima 2006
product line including LCD 37”, 42”, and 47” models with 1080p
(progressive scan) performance.
This
processing improves pixel response rates and virtually eliminates jagged
edges and other image artefacts. Scaling and colour processing
enhancements are also provided.
Progressive scan
Some
digital television broadcast formats (720p, 480p), and some higher-end DVD
players (usually 480p), use a type of video signal known as progressive
scan. Instead of splitting each video frame into two sequential fields
like standard interlaced NTSC video (480i), progressive-scan video
displays the entire frame in a single sweep. So, where standard NTSC
video displays 30 frames (60 fields) per second, progressive scan displays
60 full frames per second.
Displaying
progressive-scan video requires more bandwidth (there's twice as much
vertical information) and a faster horizontal scan frequency than
interlaced video. Progressive-scan picture quality is more film like, with
more fine detail and less flicker. For progressive-scan viewing, you'll
need a TV that's ED (Extended Definition) or HD (High Definition) capable.
QuadPlexd
A
processing method which is a combination of several new video enhancement
technologies that provide “next generation” performance for digital
progressive scan displays. Natural looking colour tones and razor sharp
details are highlighted through this video process, including dynamic edge
enhancements throughout the screen.
Rear-projection TV
Typically
referred to as "big-screen" TVs, these large-cabinet TVs generally have
built-in screens measuring at least 40". Up until a few years ago, all
rear-projection TVs used three CRT’s to create images. Using CRTs resulted
in cabinets that were relatively heavy and bulky - nearly always designed
as floor standing TVs. Some newer rear projection technologies (like DLP
and LCoS) have reduced depth on these sets (down to typical depths between
7” and 18”), but none are flat-panel thin like flat panel LCD and plasma
models.
Response Time
Commonly
these numbers accompany advertisements, brochures, user manuals, etc.
regarding LCD monitors. This number represents image response time and is
articulated in terms milliseconds (ms), such as 8ms, 12ms, 16ms, 24ms and
so on. Response time is the screen’s signal reaction speed, or the time it
takes for a liquid crystal panel to go from total white to total black and
then back again. A 16ms LCD monitor corresponds to 63 images per second,
while 12ms is equivalent to 83 images a second. The bottom line is that
quicker response times translate to smoother and more fluid images. So,
the next time you notice an advertisement shouting to the world that a
lightning quick 16ms response time, which is actually a fairly nice
standard - remember that a product that sports a 12ms response provides a
further upgrade in image smoothness and fluidity.
Resolution
The
sharpness of a video image is generally described as "lines of resolution"
or pixels. This resolution depends on two factors: the resolution of your
display and the resolution of the video signal. Since video images are
always rectangle-shaped, there is both colour resolution to consider.
Unfortunately
there is no uniform “standard” that has been accepted for this measurement
from one manufacturer to another. Generally it comes down to a subjective
decision on what constitutes viewing a pixel. A more conservative
manufacturer may test based on a virtually square pixel with little
deformation.
Another
may count a pixel when it has virtually become a line without width.
Thus
one manufacturer could claim a higher resolution and in fact have a more
distorted and less sharp picture. For this reason we caution the comparing
of resolution figures without knowing whether tests were conducted using
equally conservative methods.
Vertical
resolution: The number of horizontal
lines (or pixels) that can be resolved from the top of an image to the
bottom. (Think of hundreds of horizontal lines or dots stacked on top of
one another.)
Additionally
there is Horizontal
resolution: The number of vertical
lines (or pixels) that can be resolved from one side of an image to the
other. Horizontal resolution is a trickier concept, because while the
vertical resolution of all analogue (NTSC) video
sources
is the same, the horizontal resolution varies according to the source.
A typical televisions VHS VCR
reproduces in a range from about 230-280 lines of horizontal resolution,
while a DVD player typically ranges from 400-480.
HD-DV
camcorder output ranges typically from near 700-740 lines of horizontal
resolution and some professional models can now exceed 760. There are few
consumer playback sources beyond hard disc drives or the newest HD content
discs which offer resolution much beyond these levels, though processing
continues to improve as 720p and 1080p playback devices and video displays
expand.
RF Jacks
These
are the coaxial, screw-on connections that cable and satellite TV signals
travel through. Some TVs have dual RF Inputs to allow switching via remote
control between two signal sources (e.g. antenna and cable or antenna and
satellite).
Scaler
Scaling
is the process of converting a video signal to a resolution other than its
original. Scaling involves either “up conversion” or “down conversion”,
and may also include a conversion between progressive - and
interlaced-scan formats such as 720p to 1080i. Scaler processors are
typically part of the video processing chipsets, though you can also
purchase “outboard” external devices designed for critical “manual
control” segmentations. With the latest chipsets found in 2006-2007 HDTV
flat panel models however the visual differences in sophistication offered
by external devices are disappearing for home and even many
pro-application uses.
V-Chip
See Child Lock-out
Viewing Angles
Refers
to the angle from which you can still view the picture on the
screen. TVs with wide viewing angles mean that you don't need to be
positioned directly in front of the set to see the ideal picture your TV
is capable of.
Watts Per Channel
Typically
numbers given by a manufacturer to express available audio power output.
Unfortunately for consumers there is no agreement among all leading
manufacturers of televisions for a common standard of measurement or
even distortion level while rating TV audio. It is quite common to see
wattage specifications that are based on exceedingly high distortion
levels (10.0% is not uncommon among major TV manufacturers versus 0.1%
among many audio manufacturers).
WSXGA
Short
for Wide SXGA, WSXGA is a resolution that supports 1600 by 900 pixels or
1600 x 1024 pixels.
WUXGA
Short
for Wide Ultra Extended Graphics Array, WUXGA has a resolution of 1920
horizontal pixels by 1200 vertical pixels.
WXGA
Short
for Wide XGA, WXGA is a video resolution that supports a maximum
resolution of 1366 horizontal pixels by 768 vertical pixels.
XGA
Short
for Extended Graphics Array, XGA was introduced in 1990 and is IBM’s
upgrade to the VGA video standard. XGA supports a maximum resolution of
1024 horizontal pixels by 768 vertical pixels.
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