TV Glossary

Analog: type of television broadcasting to be phased out as of Februrary 17, 2009. Analog broadcasting can provide a resolution of up to 480 lines. New television broadcasting is moving to DTV to allow analog signals to be used by public safety communications, such as police, fire, and emergency rescue, and for some advanced commercial wireless services.

Aspect Ratio: comparison of screen width by screen height. Analog TV has an aspect ratio of 4 by 3, meaning it is 4 units wide by 3 units high. The aspect ratio of HDTV is 16 by 9, the same as the wide scope of a movie theatre screen.

Built-in Tuner: device inside a television set, allowing it to decode over-the-air signals and broadcasts without the aid of an external receiver. Most built-in tuners require an antenna to help receive the signal.

Burn-in: when a static image leaves a permanent mark on a television screen, regardless of whether it is on or off. This problem is common in CRT and Plasma televisions due to leaving an image on the screen too long. LCD televisions don't typically have a problem with burn-in.

CRT: Cathode Ray Tube. The traditional type of 'tube' television that utilizes a glass vacuum-sealed bulb to shoot electrons onto a sheet of phosphor-covered glass in order to form the colors and pictures you see on your television screen.

Digital (DTV): the "new" type of television broadcasting, set to replace analog television on February 17, 2009. Digital television is much more versatile, with better picture and sound quality than analog television.

Flat Panel: a thin (two to four inches thick) television, light enough to hang from a wall or ceiling.

HD(TV)-ready: a High-Definition television able to receive over-the-air HD signals, if paired with an external to decode the signal.

HDTV: a High-Definition television able to receive over-the-air HD signals. An HDTV is a widescreen television with an aspect ratio of 16:9, and has a resolution of either 720p or 1080i.

LCD: Liquid Crystal Display television. LCD screens work by blocking light. Basically, a solution of liquid crystals is sandwiched between two perpendicular panes of polarized glass. With this configuration, it becomes possible to manipulate the intensity of light as it passes through the crystalline matrix and out of the glass panel on the other end, producing the colors and pictures you view on the screen.

Over-The-Air (OTA): signals sent by a television broadcast company over the open airwaves. An antenna catches the signals, and a tuner decodes them. All OTA signals are free to use.

Pixels: short for 'picture element', a pixel is the tiniest bit of data in a video image. The smaller the pixels, the more can fit on one screen, increasing picture resolution.

Plasma: one of the newer television technologies; Plasma televisions use thousands of sealed, low pressure glass chambers filled with neon and xenon. Behind these chambers are colored phosphors, one red, one blue, and one green. When charged, the chambers of plasma emit UV light, which then strikes the phosphors on the display to produce colors and pictures on your screen.

Projection: 'large screen' television using either a front (located separately, and in front of the television) or rear (located in the viewing box, in the back of the television unit) projector to project the images onto a screen larger than standard televisions.

Resolution: level of picture detail, coupled with scan type. Here are some standard resolutions:

Widescreen: A television with an aspect ratio of 16:9, or 16 units wide by 9 units high; the same ratio as a movie theater screen. Widescreen TV's are associated with HDTV.