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FEATURED TECHNOLGIES
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HDTV
What is it? And why should I
buy one? Quite
simply, HDTV gives you the
picture quality that will be
the standard for the life of
your next TV set. HDTV is
the High-Definition version
of
Digital TV (DTV). With better
than DVD image capability,
it utilizes the benefits of
digital audio/video
processing. The
primary features are finer
detail via increased vertical and
horizontal resolution, a
choice of interlaced or
progressive scan and a
widescreen image
format. HDTV is the foundation
for viewing High Definition DVDs.
Various HDTV technologies
are available and in
development to provide the
viewer a wide range of
options depending on budget
and usage. We'll explain the
forms, options and features to help
the buyer make an informed
choice. There are a few
things to watch for and
watch out for.
[See
HDTV in more detail below.]
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Typical 52"
HDTV Rear
Projection Monitor |
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HDTV is a high definition version of digital TV called DTV. The
first thing you should know is that currently HDTVs come with an
NTSC tuner built-in so you can watch the programs you have been
watching via broadcast, cable or satellite. They'll just look
better! The 50+ year old analog TV standard to which, we're
accustomed, was called NTSC, while the new digital standard is
called ATSC. If you intend to receive HD programming via an
antenna, you should ensure that your set is an "Integrated
HDTV" set, meaning that both ATSC and NTSC tuners are
built-in. Cable and satellite HD programming can be received
without an ATSC tuner providing the HD CableCARD or
set-top-box connections are made. [see CableCARD sidebar]
Sets without an ATSC tuner are referred to as
HDTV-"Capable" or "Ready".
Digital TV (DTV)
eliminates the "snow" and "ghosting" common
with analog TV resulting from weak signals from distant or
screened transmitting towers. The picture clarity of an analog
set is diminished with weak or distorted signals, whereas a DTV
picture is either on or off. If the digital signal is
strong enough to be received, the picture will be as clear as
the source material being transmitted.
The ASTC standard allows for 18 different formats,
3 of which are named as SDTV,
EDTV and HDTV. HDTV
must minimally meet a 720-p or 1080-i standard. For the
moment, without trying to say which of the two is better, let's
compare them both to an analog set which is at most 480i.
Essentially, your old analog TV would only be able to scan 480
horizontal lines of picture across your screen (approx. 640
lines wide). In contrast, HDTV must be able to display 720 horizontal lines and the equivalent of
1280 vertical. If the
intersection of each vertical and horizontal line represents a
point, analog TVs would display 307,200 points or "pixels".
An HDTV set must be able to display at least 921,600 pixels,
or more than 3 times that of an analog set! If we discount
the fact that an HDTV is wider in aspect
ratio, to display the
same picture of an NTSC set on an HDTV using only the 4x3 aspect
ratio (12:9), the HDTV can minimally display over 2.25 times more
pixels; that is, much more detail. At 1080 lines
(1080x1920), an HDTV can display 2,073,600 pixels or 6 times
that of an NTSC analog set.
Another feature of HDTV is progressive scan capability. Without
defining or describing progressive
scan, the net benefit is that
an HDTV set can display individual video frames at twice the
rate of an NTSC set, resulting in much less flicker. 1080p capability on manufactured
sets is relatively new. 1080p is
something to be considered for the high-def DVD disc
playback. [see HD DVD sidebar]
The bottom line is that HDTV offers a much larger picture (bigger set)
that can be enjoyed with more
clarity and detail even with the lesser quality non-HD standard
fare. Note: many HDTV sets will upscale this 480i content to
480p or higher to improve its appearance on the larger screen.
Some DVD players will also do this upscaling.
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DVD - The
DVD-Video disc
DVDs
have now be on the market
for 10 years. In that
time, convenience, price
and the exceptional audio
and video improvement over
VHS tape has spirited many
to adopt the medium as the
preferred source of
recorded movies and
concert videos. DTS and
Dolby Digital Surround
capability along with
digital video, often in a
progressive scan stream,
bring optimum viewing
enjoyment to our TVs -- old
and new. As a digital
content format, now
referred to as standard
DVD, it has been a driving
force for big screen
digital TV purchases.
HD DVD and
Blu-ray - High Definition
DVD
Released first
in 2006, these 2 new High
Definition DVD formats
will please even the most
critical videophile.
High-def DVD will utilize
the best features of HDTV
and the most strident
audio system to deliver
unparalleled audio and
video entertainment in the
home. Enhanced
audio content in the form
of Dolby
TrueHD is yet another
level of improvement over Dolby
Digital now found on
standard DVD.
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Toshiba SD-4980 DVD player |
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Sony Blu-ray Player BDP-S1 |
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Toshiba HD DVD Player
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The DVD is a video disc format that is an outstanding audio-video source.
Playable in component players for home theatre
viewing as well as DVD-ROM drives in computers, this format has
had an unprecedented acceptance since its introduction. Unlike the
early VHS / Beta shoot-out for the ubiquitous video tape market,
DVD manufacturers agreed on one basic common standard. For
the music audio enthusiast specialized versions in DVD-Audio and
SACD followed the DVD-Video (DVD) introduction; however, these
variants had little impact on the mainstream DVD uptake.
HD DVD has been standardized by the DVD Forum (international association of 200+ companies).
HD DVD players are intended to be backward compatible with today's
standard definition (SD) DVD. In other words, the DVD disc you bought in 2002 should play
in an HD DVD player. Some studios will put SD content on one side of the disc, and HD content on the other side.
The laser aperture setting on standard DVD is 0.6, with the setting for HD DVD a slightly smaller 0.65 using a red laser.
Given HD DVD's design, the manufacturing requirements are similar to
Standard DVDs allowing the current pressing plant equipment to be used for HD DVD production.
HD DVD has a capacity of 15GB for single-sided discs and 30Gb for double-sided. It doesn't need a caddy or cartridge and the cover layer is the same thickness as current DVD discs, 0.6mm.
It is the only new format providing the ability to legally make copies of optical content. Dubbed "Managed Copy," HD DVD implements part of the AACS control mechanism
enabling user functions such as putting digital copies of a disc on a hard drive, transferring a movie (legally) to a portable player, or streaming content on a home network. Furthermore, HD DVD makes Managed Copy mandatory: all content provided on HD DVD must give users the option of making at least one copy.
The studios have the option of charging for it, although they
will likely allow one "free" copy. As Managed Copy is part of the AACS specification, this feature
is not exclusive to Microsoft or Intel projects. Toshiba has now introduced
three third generation models of HD-DVD players,
the HD-A3 at $349Cdn and the HD-A35 at $549Cdn and the mid-line
HD-A30 ($449Cdn) player
with 1080p capabilities designed to output 1920 x 1080p, the highest HD signal currently
available, via HDMI 1.3. It supports full-audio
processing, including lossless Dolby TrueHD and DTS-HD Master
Audio. The HD-A35 adds Multi Channel Signal Management to the
audio spec of the HD-A30 as well as front panel USB
extension ports. The higher end HD-XA2 at $799Cdn has the core capabilities of the
HD-A30 and also incorporates
support for Deep Color output through HDMI, and a 297MHz /
12 bit Video DAC with high-quality, 4x oversampling for increased
bandwidth.
Onkyo released its first HD DVD player
in late 2007 at $999US.
Toshiba announced that they have developed a triple-layer HD DVD-ROM disc that will have a 51 gigabyte capacity.
This begs the questions as to whether this will be as stable as the dual layer 50GB Blu-ray disc and may weaken the
argument by Blu-ray supporters that Blu-ray is best because of its data handling capacity?
Blu-ray Disc has additional capacity provided by the blue-violet laser technology.
However, in order to store a full 25GB per layer, Blu-ray has adopted a 0.85 aperture, meaning the pits on the optical layer are smaller and
potentially more error prone. In theory, the blue-violet laser, having a shorter wavelength than red, is capable of focusing more
precisely to lessen this error concern. Additionally, the smaller aperture requires a thinner disc and smaller layer spacing, which makes the medium more
vulnerable. A special protective coating has been developed to
off-set this vulnerability. A single sided Blu-ray disc capacity is 25GB.
Blu-ray dual-sided 50GB started shipping in late fall of 2006. In 2007
we saw more manufacturer's introduce Blu-ray disc players
although they were initially more expensive than HD DVD. With the significantly cheaper costs of converting existing DVD
disc production lines to HD DVD,
Blu-ray discs may remain more expensive as well.
Managed Copy has become a contentious point in the next-generation DVD battle, with HP demanding that Blu-ray require the technology on all discs.
So far, Blu-ray has said no conceding to Fox's demand that high-definition DVDs utilize a stricter copy-protection format than AACS.
Many manufacturers are supporting the Blu-ray format, even though
it is expensive, the bets being placed on the greater disc
capacity being the trump card over HD DVD in the long term.
LG released a dual- format player in March 2007 that will
solve the format question for many consumers. This player will play
both Blu-ray and HD DVD discs.
Warner announced plans to bring out a hybrid disc with Blu-ray
content on one side and HD DVD content on the other. Their recent
move to Blu-ray may set this aside.
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DVR - The
Digital Video Recorder
Whether
simply making copies or
preparing a master from
edited video, the DVR
a.k.a. PVR (personal video
recorder) is
perfect for creating, storing
and viewing your personal
videos. Now you can time
encapsulate those films
and taped videos which may
be deteriorating over
time. Once
you record TV shows or
home movies to the DVR's
hard drive, you’ve got
great editing and playback
options: Store programs
and keep them
indefinitely. Delete
them after viewing to free
up disc space. Edit your
home movies and set up
menus, wallpaper, and
playlists. Or, you can
burn content to DVD at
high speed onto DVD-R
and DVD-RW discs. A
common feature lets you
watch your favorite TV
show from the beginning
after you’ve already
begun recording it.
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SAGEM PVR-5110-S
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The DVR is a generic term for a device that is similar to
a VCR but records television data in digital format as opposed to
the VCR’s analog format. Digital Video
Recorders (DVR) encode video data in MPEG-1 or MPEG-2 formats.
Three common ways to record TV
and Video digitally include:
• A stand alone Set-Top-Box (like TiVo) that records to a
built-in hard drive.
• A stand alone Set-Top DVD Recorder that records to a
built-in DVD drive and/or a built-in hard drive.
• A Computer with a TV or Video Capture Card that records TV
and Video to the Computers hard drive.
DVRs have all of the same
functionality of VCRs (recording, playback, fast forwarding,
rewinding, pausing) plus the ability to pause "live" TV
and resume without missing any part of a program.
Should you wish to transfer your VHS video collection to a hard
disk, this may not be the solution of choice as disk space and
playability may limited. A recordable DVD may provide a
better long term portable solution.
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Digital
Surround Sound
Digital
surround is most commonly
employed in the Dolby
Digital format which
improves on the analog
version of Dolby Surround
of the 80's. Dolby Digital
provides left, right,
centre, left surround,
right surround, and
low-frequency-effects
channels. Dolby
Digital features 2
independent surround
channels, each offering
the same quality as the
front 3 channels. The LFE
channel is commonly used
through a sub-woofer to
produce the low frequency
sounds that other speakers
in the system may not be
able to reproduce.
Typically the playback
equipment can be set to,
or in some cases,
automatically detect what
channels of information is
being received and direct
the signals to the
appropriately capable
speakers in the system.
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Speaker Placement for 5.1
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Dolby Surround refers to matrix-encoded multi-channel
programming (broadcast or packaged media) intended for home
playback. It is a 2-channel mix. To play it back, Dolby Prologic
steering circuitry decodes the Dolby Surround information to
enhance separation between left, right, centre and surround
channels. In practice, 1 monaural surround channel is played
through 2 speakers - one left, one right.
The centre channel is there to keep dialog locked to the screen,
especially for off-axis viewers.
Surround sound went digital in the early 1990s, with the
introduction of Dolby AC-3 (since renamed "Dolby
Digital"). This system has three full-bandwidth channels
(left, centre, right) across the front, two discrete
full-bandwidth surround channels, plus a sixth channel devoted to
powerful low-frequency effects. This bandwidth-limited LFE channel
is the .1 in the expression "5.1-channel," and is
sometimes known as the subwoofer channel. On a movie film only a
small area is available for a soundtrack. To get 5.1 channels of
digital audio into this small area requires a considerable amount of data compression. This space can
accommodate less than one-tenth the space that would be required
if regular PCM (pulse-code modulation, the digital coding scheme
used for CD) were used. It does this with a sophisticated
perceptual coding system that analyzes signal content, and assigns
bits only to portions of the signal that are audible (as opposed
to portions that are masked by other sounds).
Dolby Digital 5.1 has several advantages over Dolby Surround.
First, there are more channels: two surround channels as opposed
to a monaural surround played through two speakers. Next, whereas
Dolby Surround matrix-encodes four channels onto a two-channel
signal, with Dolby Digital all channels are fully discrete,
providing inherently better separation. Moreover, the surround
channels are full-bandwidth, rather than having limited bass and
treble. Lastly, Dolby Digital has a dedicated subwoofer channel.
The bottom line: Dolby Digital 5.1 allows for more dramatic, more
convincing surround effects than Dolby Surround.
It is important to distinguish between Dolby Digital and Dolby
Digital 5.1. Dolby Digital refers to the coding system that is
used to reduce data requirements. A Dolby Digital signal can have
one, two, four, 5.1 or more channels. Many classic movies on DVD
have mono soundtracks that are encoded in Dolby Digital. Many
movies from the 1980s have Dolby Surround soundtracks encoded in
Dolby Digital. And of course, there are many recent blockbusters
with 5.1-channel Dolby Digital soundtracks.
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DLP™
Front Projection Systems
A portable DLP™
front-projection system is a
smart choice for home theatre
and business. Today's DLP™
projectors come in two basic
technologies: single-chip DLP™
and three-chip DLP™. They
are so compact and lightweight
that they can be hidden on a
bookshelf, entirely out of
view. Currently you can find
single-chip DLP™ projectors
that weigh less than three
pounds; however, for a
super-sized home theater
screen you may wish to go with
a larger less portable unit. Digital Light
Processing (DLP™) uses a
single Digital Mirror Device (DMD)
chip that has thousands of
tiny mirrors, each
representing a single pixel.
These mirrors tilt back and
forth and deflect light as
instructed by the source
signal to
create the image. Light
greys are created with the
mirror deflecting light more
often than not, whereas a dark
grey is created with the
mirror in its off (non
reflecting position) more
often than not. Colour
is introduced by a colour
wheel passing the reflected
light through the appropriate
colour segment of the wheel.
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Optoma HD81 DLP Projector
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For Home Theater use, the ultimate HDTV resolution, 1080p (1920 x 1080) is now available
in chipsets for the DLP™ front
projection market. Available for both single-chip and 3-chip
applications they enable incredible detail for the ultimate HD
viewing experience.
One of the difficulties with film projection is that between each image frame a shutter is used to blank
out the projection light until the next frame is in view. This results in flicker which at 24 frames/sec. the
human eye can trick us into not noticing. A CRT television, which scans lines of picture frame with blanks between
frames, also introduces flicker. Since the DMD (digital mirror device) in a DLP projector is not scanned
like a CRT but is a virtually continuous display device, the display can be driven at 24 fps with no objectionable
flicker. Unlike a film projector, DLP Cinema™ technology does not involve the use of a shutter. Since there is no
film being mechanically pulled through a film gate, there is no need to
blank out the light. This results in
a flicker-free display and a more efficient use of the lamp output.
DLP™ data projectors come in different
"fixed" resolutions. That is, each projector has a
"native" resolution which may vary from other
projectors. And, a projector's fixed
resolution rarely matches the exact resolution of the incoming
signal. Therefore, the projector must first resize the signal's
image internally, through shrinking or stretching, to map it onto
its own fixed-resolution DLP™ panel.
For example, 2 of the common fixed resolutions are SVGA (800 x 600
pixels) XGA (1024 x 768 pixels). These names represent the various fixed resolutions of a DLP™
projector's internal panel, onto which an incoming signal must
first be mapped before it can then be projected. SVGA and XGA are
currently the most common resolutions in the marketplace. SVGA,
being of lower resolution (800 pixels wide x 600 pixels high), is
less expensive than XGA (1024 x 768), but doesn't provide
sufficient resolution to do justice to HDTV signals. Suppose you
have an XGA projector with an 800 x 600 incoming signal from a
video source. The incoming image will need to be stretched to
match the panel's fixed resolution of 1024 x 768 pixels. A
mathematical algorithm is used to add/interpolate pixels within
the expanded image, so that the density of pixels will remain the
same as in the original signal, thus avoiding what otherwise would
be a less dense and therefore blotchy picture.
Excellent color is one of the benefits of DLP with extremely tight spacing between the tiny mirrors on a DMD.
Also, brightness is higher in DLP compared to LCD as light is reflected with a DLP vs. having to pass
through the liquid crystal panel of an LCD. see more ...
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LCD
Front Projection Systems
In
Liquid Crystal Display
projectors, a light source
shines through a layer of
liquid crystal material. It is
a transmissive technology
where the bright light passes
through the transparent LCD
chip made up of individual
pixels which together form the
image and projecting that
image through a lens to a
large projection screen. An
electrical charge is applied
to the crystals in the layer,
causing them to rotate the
plane of polarized light - in
effect, turning different
colors on or off. Each pixel (colour
dot) projected to a screen is
generated by three separate
crystal cells, one each to
produce red, green and blue
color signals. The polarized
light coming out of the layers
passes through a prism to
create the unified projected
image which we see. Newer
projectors use polysilicon
transistors - which are
smaller, absorb less light
(making the projected image
brighter) and switch faster
than earlier generations - and
have three separate layers to
produce the colour signals
going into the projection
prism. The small size of the
LCD chip helps to make this an
economical technology.
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Sanyo PLV-Z5 16:9 LCD Projector
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Since LCD chips have a finite number of pixels, signal inputs that have higher resolutions must be scaled to
fit the pixel count of the LCD chip. For example, an HDTV input format of 1080i needs a native display of
1920x1080 pixels for a one-to-one display of the HDTV image. However, if your LCD chip only has a pixel
field of 1024x768, the original HDTV signal must be scaled to fit the 1024x768 pixel count on the LCD chip.
LCD projectors today typically contain three separate LCD chip panels, one each for the red, green, and blue
components of the video signal. The light is then recombined, using a dichroic prism. The combined full color
image passes through the lens to your screen.
When the image is expanded to a large screen, these individual pixels may be visible creating what is
known as the "screen door effect".
Unlike the CRT, LCD is not subject to burn-in; hence, static images left on the screen or video games will
not leave a permanent "ghost" image. On the
negative side, a pixel may "burn-out" leaving a black or
white pixel spot projected to your screen.
There is no repair solution other than replacing the affected LCD
panel.
Since 2004, the dynamic iris has been added to LCD projectors to deliver more contrast - previously a weakness
in comparison to DLP projectors.
LCD projectors use less energy and create less heat that other projector technologies, enabling a quieter cooling fan.
LCDs are prone to motion artifacts. In part, this is related to
the way an LCD functions like a film projector which can only
display single frames of video. LCDs look very good with
progressive, frame-based images; however, they have difficulty
dealing with field-based interlaced video. Interlaced images
must be fully assembled into a single video frame through a
process called de-interlacing. Where a fast moving object
such as a waving flag is de-interlaced, two images (one for each
field) are displayed on the LCD panel. The difference in
motion of each field can be perceived by our eyes as two objects
in motion creating a blurring effect, almost as if there are two flags.
This temporal-spatial
blur can be reduced by displaying each field as a progressive
image, but this requires considerable image processing, especially
if it is to be up-scaled to a higher resolution. Much
interpolation must be done.
Often, the pixel response time is blamed for this blur. Pixel response is a measure
of the time it takes to go from black to white and back to black again, or in another definition from 90% black to
90% white and back. In a quality LCD display, the pixel response is fast enough to avoid seeing a
transition effect,
similar to a video dissolve, that might occur with each frame update.
see more ...
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Plasma Screen
Significant advances in
plasma panels allow
displays that now approach
the deep blacks that tubes
excel at. The best plasmas
can produce nearly
CRT-quality images, with
excellent color and
viewing angles. But a
large screen in a flat
panel comes at a high
price. The fear of burn-in
with plasma is no longer
an issue, as a typical
usage will give 10 to 20
years before reaching
half-brightness, similar
to a direct view CRT or
LCD. Each
Plasma screen pixel is
made up of three
fluorescent lights - a red
light, a green light and a
blue light. These plasma
gas lights are turned on
by video signal controlled
electrodes that cause
particle collisions to
excite the gas atoms in
the plasma, causing them
to release ultraviolet
photons of energy. These
in turn interact with
phosphor material coated
on the inside wall of the
plasma cell. The light
created is what we view on
the face of the screen.
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Pioneer Elite PRO-FHD1
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The Plasma flat screen display is made up of thousands of
plasma gas- filled cells. The phosphors in a plasma display give
off colored light when they are excited. Every pixel is made up of
three separate subpixel cells, each with different coloured
phosphors. One subpixel has a red light phosphor, another has a
green light phosphor and the 3rd subpixel has a blue light
phosphor. These colours blend together to create the overall
colour
of the pixel. By varying the pulses of current flowing through the
different cells, the control system can increase or decrease the
intensity of each subpixel colour to create hundreds of different
combinations of red, green and blue. In this way, the control
system can produce colours across the entire spectrum.
The main
advantage of plasma display technology is that you can produce a
very wide screen using extremely thin materials. And because each
pixel is lit individually, the image is very bright and readily
seen over a wide viewing angle. The best cathode ray tube (CRT)
sets have a slight image quality edge over current top line plasma
sets; however, plasma's 6" thin depth makes plasma an
excellent lifestyle choice.
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LCD Flat
Screen
Flat LCDs are very popular
in screen sizes below 37
inches due to their
stylish looks and slim
depth allowing placement
virtually anywhere. Larger
LCDs up to 57 inches have
been announced but remain
quite expensive compared
to plasma and
rear-projection models.
LCD panels are more energy
efficient than Plasma or
CRT sets. Some viewers
suggest that LCD images
appear slightly smoother
than plasma at the same
viewing distance. LCDs suffer from the
inability to achieve a
true black due to light
leakage through the
pixels. Color
saturation and purity is
also generally inferior to
plasma, again as a result
of the inability to
completely blacken (turn
off) the pixels. A
slightly narrower viewing angle
than plasma results in
brightness and color shift
as the viewer moves to
extreme side angles away from a head-on view.
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Panasonic TC32LX50 LCD
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How an LCD TV panel works
An LCD TV is sometimes referred to as a "transmissive"
display as a light source (bulb) behind the panel shines light
through the display. A white diffusion panel behind the LCD
redirects and scatters the light evenly to ensure a uniform image.
The display consists of two polarizing transparent panels and a
liquid crystal solution sandwiched in between. The screen's front
layer of glass is etched on the inside surface in a grid pattern
to form a template for the layer of liquid crystals. Liquid
crystals are rod-shaped molecules that bend light in response to
an electric current — the crystals align so that light cannot
pass through them. Each crystal acts like a shutter, either
allowing light to pass through or blocking the light. The pattern
of transparent and dark crystals forms the image.
LCD TVs use an advanced "active-matrix" LCD. This design
is based on thin film transistors (TFT) -- basically, tiny
switching transistors and capacitors that are arranged in a matrix
on a glass substrate. Their job is to rapidly switch the LCD's
pixels on and off. In a color TV's LCD, each color pixel is
created by three sub-pixels with red, green and blue color
filters.
One of the biggest challenges for LCD TV manufacturers has been
speeding up the "pixel response" time (how fast an
individual pixel's color can change without blurring) to ensure
that fast-moving objects don't exhibit "motion lag" or
ghosting. It's especially critical for larger-screen LCD TVs where
much of the viewing will be DVD movies and/or HDTV.
An LCD screen doesn't have a coating of phosphor dots. That means
you'll never have to worry about image burn-in, which is great
news, especially for anyone planning to connect a PC or video game
system. LCD TVs are extremely energy-efficient, typically
consuming 60% less power than comparably-sized tube-type
direct-view TVs. It also means LCDs run cooler than plasmas, minimizing the need for
a potentially noisy cooling fan.
Variants of LCD video projection
technology in use are: LCoS (Liquid Crystal on Silicon), D-ILA
(Digital Imaging Light Amplification - developed and used by JVC),
and SXRD (Silicon Crystal Reflective Display - developed
and used by Sony).
LCoS is an emerging technology owing its heritage to
both LCD and DLP. Like LCD, each pixel has liquid crystals that
untwist to filter light, and are applied to a silicon chip instead
of sandwiched between glass. Like DLP, light is reflected off the
chip toward a screen. Because it uses smaller pixels than LCD, a
higher resolution can be attained virtually eliminating the
"screen door" effect of LCD. Limited availability
currently makes this technology a minor contender. The difficulty
of producing very dark blacks also presents a negative to offset
the higher resolution benefit.
OLED: (pronounced "Oh-Led") Organic Light
Emitting Diode The Sony XEL-1, at $2,500 is pricey for
an 11-inch screen; however, its 3 millimeters deep panel (about
the thickness of three credit cards) anticipated deep black
levels, high contrast ratios, rapid response times and low power
consumption may
foreshadow great HDTV promise for the future.
OLED's chemical-compound layers between two charged electrodes
do not require backlighting. Self-lit, they produce more
brightness with less power than LCD.
The question remains for this technology: Can OLED be produced
in larger sizes economically and in large quantities?
SED (Super-conduction Electron-emitter Display) is a
flat panel technology which is expected to reach the market
shortly once its major proponents, Canon, Toshiba and Nano-Proprietary
have settled some legal issues allowing the product to be
manufactured. Essentially it's a CRT flat panel with each
sub-pixel driven by its own electron gun. The SED TV is expected to produce brighter pictures,
more accurate color, better motion handling and use less energy
than other flat-panel TVs. Production costs in volume could be on
a par or better than plasma or LCD sets; however, with a launch
date unknown, Plasma and LCD may be far enough
ahead that SED may never catch up.
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Media
Center
- tying it all together
The
media center deals with
removing the difficulty of
working with many
electronic devices, media
types and differing
formats. Secondly, the
complexity of media
applications and family
interests is addressed.
The challenge is getting
photos and video from the
Internet, cameras,
computers, music systems
and video players into or
controllable from an
easily accessible and
usable central device.
Many
manufacturers are
developing their
implementation of a Media
Center, some with their
own software including the
GUI which the user sees
and interacts with on
their computer or TV
display. Others are
based upon the Microsoft
Windows Media Center
software now available as
an option with Windows XP.
As more of these products
come to market some will
utilize the Dual
Core Intel Pentium® D
Processor and Intel's Viiv
technology and Microsoft's
Vista with new Media
Center enhancements.
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A Media Center Example
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Media Center technology faces challenges of
interoperability between various devices, especially between
computer and home entertainment devices. Often the connectivity
and communication protocols of devices are incompatible.
Some Media Center solutions take the approach of turning
the home PC into a home entertainment Media server. A simple and
intuitive operating interface may enable users to watch both
analog and digital TV, play DVDs, listen to music and radio,
browse the internet, view photo slideshows, and watch video from a
web cam -- all on a PC or notebook. The remote control-based
interface does not require traditional navigation using a keyboard
or mouse.
Other Media Center solutions are
dedicated set-top-box implementations which treat the PC as just
one of the program material sources.
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Connections - Various connectors and cables are available to carry audio
and video signals between components in a home theatre system. The following
section will give an overview of typical connections.
HDMI - a single cable provides digital video and audio connection between devices. With High Definition sources such as
HD DVD, Blu-ray disc, and HD satellite, this cable can carry signals for up to 1920 x 1080p video and enhanced lossless
digital audio signals including Dolby TrueHD and DTS-HD Master Audio.
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