LED (Light Emitting Diode)

An LED is a solid-state type of video display that is used to provide information on the status or operation of audio/video components

Line Conditioner

A line conditioner, or surge protector, is an electronic device that “cleans” the electricity coming from a wall outlet. It protects audio/video components from electric spikes and surges that can cause damage to the components. The line conditioner plugs into a standard wall outlet, and audio/video components are plugged into outlets on the line conditioner.

LCD (Liquid Crystal Display)

LCD is a type of video display using liquid crystals sealed between two pieces of glass like material Liquid crystals change the amount of light they allow to pass through them when an electric current is applied.

Because LCD video displays don’t require a tube, they are thin and flat. While their profile is thinner, the picture degrades when the screen size gets too large, so smaller LCD displays provide a better quality picture.

Learning Remote Control

A learning remote control is a type of remote control that can learn commands from other remote controls. Learning remotes can be taught a wide range of commands. They are able to duplicate all the functions of most other remote controls, allowing them to replace a group of remotes with a single remote. A learning remote can operate several types of components.

Letterbox

Letterbox is a video display format (used mainly for DVDs) with a widescreen aspect ratio, similar to a movie screen. Movies are shot in widescreen format, and designed to be shown in a theater. When a movie is displayed on a standard (4x3 aspect ratio) TV, if you fit the image to the height of the television, the image is too wide for the TV screen, which means the sides of the image are cut off. Letterbox format fits the image to the width of the screen, so the entire picture is shown. However, the picture does not fill the height of the television screen, so black bars fill in the extra space above and below the image.

Line Doubler

A line doubler recombines the odd and even fields of a frame into one sequential, progressive signal. This signal is much cleaner and produces a better image. In addition, the lines are displayed in half the time, so the line doubler displays the same frame a second time, which increases image brightness and stability.

The result is an image with more greater detail and clarity than a traditional, interlaced video image.

Some TVs have line doublers built in.

Line Level

Line level is a term for a low-level signal sent over cables that connect components in an audio/video system. Line level signals transfer information from a component to an amplifier. The amplifier’s job is to take the line level signal and expand its power.

Low Noise Pre-amplifier

Some RCA TVs include a low noise preamplifier, which minimizes both audio and video “noise.” Pre-recorded movies sound richer, cleaner, and more distinctive.

Lumen

A lumen is a measurement unit of illumination. Lumens are often stated in video display specifications. Higher values mean that the display is able to output more illumination, or more light. With higher light output, a video display is easier to see in a brightly lit room. This is especially important with front projection systems, which usually work better in dim lighting.

Luminance

Luminance is the portion of a video signal, which carries the information for brightness, darkness and contrast. Luminance ranges from pure black to pure white. Luminance is combined with the color portion (chrominance) of the signal to form a complete video image.

The chrominance portion of the signal tells a video display what color to show. The luminance value adjusts the color to be light or dark, bright or shadowed, so it has the proper contrast and color depth. Chrominance is abbreviated with the letter “C” and luminance is abbreviated with the letter “Y.”