Glossary of Terms
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Lacing: A common method of attaching a fabric covering to the frame of an awning. It is tied to the frame using thin rope that is threaded through grommets at the edge of the fabric.
Lacquer: A clear glossy coating applied to material for appearance and protection. It is known for its ability to dry quickly. Similar to varnish but provides a harder finish.
Lambert: A unit of measure of luminance (brightness). One lambert is the luminance of a surface that emits or reflects one lumen per square centimeter. One lambert = 0.318 foot-candles per square centimeter.
Lamination: The process of binding together two or more layers of material by means of one or more of the following: heat, pressure and adhesive bonding. (See also delamination.)
Lamp bank: The array of lamps (lights) in a message centre that are used to create the messages seen by the public.
Landscape format: An image or sign panel where the length is appreciably greater than the height is said to be in landscape format. (See also portrait format.)
Lap joint: A connection or joint in which two pieces of material are overlapped before fastening.
Large format printer: Are generally accepted to be printers with a print width between 17" and 100". Large format printers are used to print banners, posters and general signage and in many cases are more economical than short-run methods such as screenprinting. Wide format printers most commonly use a roll stock material however direct substrate or flat stock printers are becoming more popular. (See also plotter.)
Laser: A highly focused beam of light that when generated with sufficient power can be used for the purpose of engraving or cutting material.
Layout: The overall arrangement or design of the graphics and lettering on the face of a sign.
LCD (liquid crystal display): A type of changeable copy sign utilizing liquid crystals that become opaque or clear when exposed to a controlled voltage. LCDs are commonly used in some time and temperature displays and electronic message centres.
LED (light emitting diode): Consists of a small light source that emits coloured light (usually red, but also green, yellow, blue and white) from a very small amount of electricity and is used for electronic "message" signs. These signs became popular in the 1970s because they were inexpensive and allowed scrolling/changing messages to be used in commercial applications. Advances in LED technology have made them more useful for interior and exterior message displays. With further advances in technology LEDs have become a highly efficient source of sign illumination.
Letter spacing: A typographic term for the space between letters and words.
Life safety signs: Signage that conveys life-saving information such as important fire, security and evacuation information. The specific types of life safety signage required are determined by government regulations.
Light box: A sign that is self enclosed in a typically square or rectangular structure and houses an internal light system for illumination of the sign face. (See also box sign.)
Line screen: Used to define the density of a screened or halftone image. That is, a 133-line screen contains a pattern with 133 halftone dots per linear inch. The higher the number, the higher the resolution, and in turn the higher quality of detail in reproduction of original artwork.
Line spacing: A typographic term for the space between lines or blocks of text.
Load: Any measurable force exerted on a structure or object. Things that can add load to a sign and its supporting structure include water, snow and wind. (See also dead load.)
Logo: A group of letters, words, symbols, or shapes used to represent a business, product or service. The use of a company’s logo can be regulated and protected once it is registered. (See also trademark.)
Logo sign: Refers to a wall sign located on the uppermost story of a building incorporating a logo that identifies a particular building or occupant of the building.
Low profile sign: A freestanding sign built close to the ground or on top of a base sitting directly on the ground. Often incorporates the support structure into the overall design. (See also monument sign.)
LRV (light reflectance value): An indication of the relative amount of light reflected by a given colour. For example, yellow has a higher LRV than blue.
Lumen: A measurement of light output. One lumen equals the amount of light falling on a one square foot area located one foot away from a single candle.
Luminance: The intensity of a light emitted by a source as measured in a given direction. Luminance is a measure of the amount of light only. It is expressed as footlamberts or candelas per square foot or meter respectively.
Luminance ratio: With an illuminated sign, some areas of the sign face will have a higher luminance than others. The difference in luminance between any two areas is referred to as the luminance ratio.
Luminescence: The quality of emitting light by absorbing radiant energy from another source and converting it into a visible wavelength.