Lacquer:
A clear finishing material similar to varnish and preferred by sign makers because of its abilities to dry quickly and to not be affected by the presence of dust. It may also be used as a binder with pigments such as silver dust.
Laminated Glass:
A glazing material consisting of outer layers of glass laminated to (and held together by), and encasing, an inner layer of transparent polycarbonate film. In graphics and architecture, patterns and images can be applied to the plastic interlayer to create desired design effect.
Lamination:
A process by which different materials are lacquered and then bonded together. The end result may be the creation of a substrate, such as medium-density overlay (MDO), or protection of the underlying surface, as when a clear plastic film is laminated to a decorated surface.
Lamp Bank:
The part of a message center that the public sees; a regular array of small lamps which display messages by their on and off patterns.
Lap Joint:
A connection in which two pieces of material are overlapped before fastening.
Lateral Force:
A force acting in a horizontal direction, such as wind, earthquake, or soil pressure against a sign face, foundation wall, or footing.
Lay-out:
The total arrangement of a sign's graphics. Shows the overall plan of how the art copy will be arranged on the face.
LCD (liquid crystal display) sign:
A type of changeable copy sign utilizing liquid crystals that become opaque or clear when exposed to a controlled voltage. Although LCDs are most common in calculators and digital watches, they are also used in some time and temperature displays.
LED (light emitting diode) sign:
Consists of a small light source that emits colored 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. See also electronic message signs.
Legibility:
The quality of a sign's typefaces that allows it to be easily read and deciphered. See also readability.
Letter spacing:
The addition of space between individual characters or numerals. See also tracking.
Letter Styles:
Serif, sans serif, slab serif, italic, light, roman, medium, demi-bold, bold, extra bold. See also font.z
An established set of numbers representing approximate visibility of letters over a range of distances. Ranges from a 3" letter which has a maximum impact readable distance of 30' and a maximum readable distance of to a 60" letter which has a maximum impact readable distance of 600' and a maximum readable distance of 2500'. Readable distances vary with various color combinations and type faces as well as with surrounding visual busyness, and whether the observer is still or in motion.
A trade name for polycarbonate plastic sheeting.
Typographic term from the long-gone days of cold leaature, leading refers to line spacing.
Lexan:
A trade name for polycarbonate plastic sheeting.
Life Safety Signs:
Used for police, fire, security, evacuation, and other life safety information, subject to local code enforcement and review.
Light Emitting Diode (LED) Sign:
See led sign.
Light Reflectance Value (LRV):
The amount of light reflected by a given color. For instance, yellow has a higher light reflectance value than purple does.
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:
Typographic term used to describe distance from letter baseline to letter baseline in blocks of text. Also called leading.
Lines:
In lamp arrays, vertically stacked lamp banks creating a single line of copy. A line is typically seven or nine lamps in height.
Liquid Crystal Display (LCD) Sign:
See LCD sign.
Logo:
An often stylized group of letters, words, symbols, or shapes used to represent a business or product. The use of a company's logo can be regulated by the federal government once it is registered. See also trademark.
LRV:
See light reflectance value.
Lumen:
A unit of measurement of light.
Luminescence:
The quality of given off light by the absorption of radiant energy. Used to describe any cold light. See also fluorescent.
Luminous Tubing:
See neon tubing.
