Hdtv Jargon
720-line HD
The 720-line system is the most common format for the launch of HD television. The 720-line system is 1280 pixels across, so the resolution is 1280 x 720, giving just over twice the resolution of a 625-line standard definition picture.
1080-line HD
The 1080-line system is the other common HD format.
A 1080-line system has 1080 vertical pixels and 1920 horizontal pixels, with up to five times the resolution of a standard definition picture.
Aspect Ratio
This refers to the ratio of a pictures width relative to its height. The aspect ratio of a standard television is 4:3, whereas HDTV has an aspect ratio of 16:9, for a more intense viewing experience. The more common names for aspect ratio are Widescreen or Letter-box .
AC-3
Also known as Dolby Digital this is the 5.1 channel sound system specified in the Standard for Digital HDTV, delivering CD quality digital audio from six speakers, front left, right and center (where most of the voice comes from), rear left and right plus a sub woofer for depth, to produce a cinematic sound! True 5.1-channel sound is only available via a home cinema system
Bit Rate
Bits per second or bps, expresses the rate at which data is transmitted. Generally, the higher the bit rate, the better the image and sound quality.
Brightness
Expressed as candelas per square meter (cd/m2) brightness simply indicates how much light is emitted by the screen. A higher candelas means a brighter picture.
Component Video
Three connectors (usually red, green and blue RCA jacks) that transmit and receive component video signals. The combination of these signals conveys all the picture information.
Contrast Ratio
Essentially contrast ratio is a comparison of a screens blackest black and whitest white.A higher contrast ratio indicates that on screen colors will be richer.
DVI
Digital Video Interface. DVI is a type of cable connector which provides a high band width connection between a video source and a display device.
EPG
Electronic Programmer Guide. An onscreen display of channels and programmer data.
HDMI
High Definition Multimedia Interface is a digital connection for video/audio data. It ensures a high-quality video signal is delivered to your display via a single cable.
HDCP
This is a copyright protection system that is incorporated into HD receivers and displays. It stands for High definition Digital Content Protection and prevents unauthorized use of content which is copyrighted.
LCD TV
Liquid Crystal Displays are flat-panel televisions designed to offer superior images. A liquid crystal solution is sandwiched between two panels and electrified. This causes the crystals to act as shutters , some allowing light to pass through, other blocking light out. These shutters on the electrified crystals form the image on the LCD TV.
Pixels
A pixel is literally a single dot on the screen and the pixels form the image on your display. The more pixels, the better the picture. With HDTV there are many more pixels (typically 1920 x 1080 or 1280 x 720) than with Standard Definition TV (720 x 576), giving a crisper, clearer and sharper picture.
Plasma Display
A compatible plasma TV is one way to display HDTV. The image is created by hundreds of thousands of tiny cells filled by ionized gas in a plasma state.
Resolution
The measure of the amount of detail an image can show. HD has a maximum resolution of 1920 x 1080 which equates to 2,073,000 pixels whereas standard definition has a resolution of 720 x 576. The higher the resolution the better the resulting image.
Standard Definition (SDTV)
This is the traditional definition television system, currently used. A standard definition picture is 720 x 576 pixels.
Viewing Angle
LCDs were originally designed as computer monitors, and as such were designed for head on viewing. Viewed at an angle these early screens lost much of their contrast and brightness. In response to this manufacturers are continually increasing viewing angles for LCDs where the quality is retained. Viewing angles as high as 176 degrees are now being achieved.
