A comprehensive visual communications glossary of terms and acronyms used in the fields ofdigital and electric signage, wide-format inkjet printing and in traditional sign making.
Editor’s note: Words within definitions that appear in italics are defined elsewhere within the glossary.
- A -
Abatement—In sign law, the removal or control of an annoyance; such as a sign not meeting a community’s sign code.
Absorption—The dispersal of visible light as it interacts with matter, decreasing its transmission and resulting in a modification of the matter’s color.
AC Ripple—When an alternating current voltage is rectified and filtered by a capacitor, the output waveform is not perfect like the direct current from a battery. There is normally a small periodic change in the voltage level superimposed on the average DC voltage. The larger the capacitor, the smaller this ripple will be. In a practical design, a capacitor large enough to limit the ripple voltage to 10% of the average DC voltage is considered a good rule of thumb. Also called, more correctly, a “ripple voltage.”
Acceleration—The force of a knife-plotter head moving from a stopped position to its fastest linear (straight-line) speed. Measured in grams, it gives the zero-to-60 indication of plotter speed, but a better overall indication is throughput.
Acetate—A tough, clear plastic film that’s ink-receptive.
Acid Etching—Primarily used for marking glass, some surface material is dissolved in acid and removed, leaving an image behind.
Acrylic—An extruded or cast rigid plastic characterized by its clarity and colorability. Also a type of paint with an acrylic resin base.
ActiveX—A Microsoft program for enhancing interactivity in Web browsers and other network-oriented software applications.
Ad Channel—In electronic digital signage, network TV channels that exist for the sole purpose of advertisements.
ADA (Americans with Disabilities Act)—Federal civil-rights legislation addressing the needs of physically impaired citizens. Sections dealing with signage include Title II, affecting government and public-sector activities, and Title III, involving the private sector. Additional rules are included in the ADA Accessibility Guidelines (ADAAG).
Additive Colors—An emissive color system using the primary colors red, green and blue. Used in computer monitors, televisions etc. When the three come together in equal proportions, the end result is white. Also known as additive primaries.
Adhesive—A material able to hold two surfaces together, often activated by heat or pressure.
Airbrush—A device utilizing compressed air to generate a fine spray of paint.
Alternating Current (AC)—One of the three basic forms of electricity. Specifically, a current that changes direction back and forth at some frequency—60Hz in the U.S.; 50Hz in Europe—as in the electricity that comes from a household wall socket. See also Direct Current.
AMLCD (Active Matrix Liquid Crystal Display)—An electronic graphics display utilizing a grid of switching elements on the inside surface of a glass substrate, arranged in rows and columns. Voltage is applied to each row, then removed, and applied to the next row in repeated cycles, resulting in a visible image.
Ambient Light—The light in a given area, excluding direct or internal illumination.
Ampere—A unit used to measure electric current flow, also called amp or amps.
Anchor—In sign making, refers particularly to the fasteners used to secure awnings and fascia signs to facades.
Animated Sign—A sign that shows motion or changes in copy or color by means of an electric or electronic switching device. See Flasher.
Animation — A sequence of frames that, when played in order at sufficient speed, presents a smoothly moving image like a film or video. An animation can be digitized video, computer-generated graphics, or a combination.
AnimClip—An animation in the FLC or AnimGIF format which has been loaded as a clip. Like clips, animclips can be moved and sized; like animations, their speed and other animation parameters can be controlled. See also MovieClip.
Anneal—To subject to great heat, and then cool slowly. Neon tubes are annealed after bending to reduce stress in the glass.
Anodizing—Process by which a protective aluminum oxide layer is applied to an underlying metal using electrolysis.
ANSI—American National Standards Institute, a nonprofit organization overseeing standards for products, processes, systems, and services in the U.S.
Anti-Aliasing—In digital printing, the process of mixing various amounts of surrounding colors to pixels (or dots) forming lines or edges of colors. Helps eliminate the jagged look that sometimes occurs.
Application Tape—See Transfer Tape.
Argon—An inert gas which, when mixed with mercury, is used in fluorescent lamps and neon tubes.
Architectural Gauge—Thicker (1/4”) plastic engraving substrate designed mainly for sign making. Allows for deeper removal of material and appearance of greater depth.
Architectural Sign—A sign type, often part of a system of signs, associated with the architecture of a building or building complex, giving information about specific locations within, wayfinding and other features.
Ascender—In typography, a given typeface, the portions of the lowercase b,d,f,h,k and l, that extend above the height of the lowercase x.
Aspect Ratio—The height-to-width measurement of an image as displayed on a monitor and ultimately printed. Can sometimes be altered when using a software’s import/export feature and transferring an image from one computer to another. Ratio can also change with pixel size, although most computers use a 1:1 aspect.
ATM Toppers—Video screens built into automatic teller machines that run advertising and other information independent of the ATM.
Attribute—A distinguishing characteristic. The characteristics of color are such attributes as hue, lightness and saturation.
Authoring System—Software for assembling multimedia applications.
Authoring Tools—Authoring tools can refers to software that helps multimedia developers create products. These are different from programming languages in that they attempt to reduce the amount of programming expertise required in order to be productive.
Awning—A shelter constructed of non-rigid materials on a supporting framework which projects from and is supported by the exterior wall of a building. An awning may or may not be illuminated and/or decorated with graphics to serve as a sign.
Axis Swapping—The process where sign-production software temporarily transposes a plotter’s X and Y axes. The function allows long, thin jobs along the X-axis to be cut across a vinyl sheet’s width, saving material.
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Baked Enamel—A type of metal sign finish. A special enamel paint is sprayed or screen printed on the metal surface, dried, then cured. The result is an extremely durable surface similar to that found on many appliances.
Balance—In design, the relationship between the design elements so that opposing forces have equal distribution of weight in the layout.
Ballast—A device that operates as part of a fluorescent lamp and is designed primarily to provide sufficient starting voltage.
Banding—A pattern of horizontal or vertical lines visible in solid colors, continuous-tone tints, gradations or images, instead of a smooth color or transition of colors. Banding can appear on computer monitors displaying an inadequate number of colors, or on printers with an improperly profiled printer or media.
Bandwidth—The amount of data that is able to be sent over a network, measured in Kilobytes and Megabytes per second (Kbps and Mbps). Modern low bandwidth communications include dialup modems and ISDN, ranging from 56Kbps to 128Kbps, but actual downloading times are closer to 1/10th of this speed. High-speed cable modems, DSL, T-1, and Satellite are much faster, by factors of as little as 10 or even higher than 100.
Beta Testing—Testing a pre-release version of a piece of equipment or software by making it available to selected users.
Bevel—A three-dimensional effect that can be applied to text elements, clips or the edges of dimensional signs.
Bezier Curve—A line segment where the angle deflection is mathematically estimated. Bezier segments usually feature movable control points that allow nearly unlimited alteration of the segment to a variety of angles.
Binder—A substance that binds two others together. For instance, lacquer is used as a binder when painting with some metallic dusts, and many paints require binders.
Bio-Solvent Inks—A type of solvent ink in which the alcohol-based carrier (ethyl lactate) is derived from renewable resources such as corn. Ethyl lactate is very low in harmful VOCs and is considered by the EPA to be a viable alternative to cyclohexanone.
Bit Depth—In scanning technology, the amount of information a given scanner records for each pixel. The higher the scanner’s bit depth, the more accurately it can describe what it sees when it looks at a given pixel. Most color scanners today are at least 24-bit, meaning that they collect 8 bits of information about each of the primary scanning colors: red, blue, and green. A 30-bit scanner would collect 10 bits per color.
- AI = Adobe Illustrator Encapsulated PostScript
- BMP = Windows Bitmap
- EPS = Encapsulated PostScript
- GIF = Graphics Exchange Format
- JPEG or JPG = Joint Photographic Experts Group
- PCD = Kodak Photo CD
- PCX = ZSoft Paintbrush Exchange
- PICT, PCT = QuickDraw Picture Format
- RTL = Hewlett Packard Bitmap Format
- SCT = Scitex
- TGA = Targa
- TIF, TIFF = Tagged Image File Format
Black—The color that is produced when an object absorbs all wavelengths of light rather than reflecting some of them as other colors.
Black Generation—The addition of a black layer to the process colors cyan, magenta and yellow when converting an RGB color image to CMYK mode, usually handled in one of four ways: short-range black, used with camera/enlarger separations made through colored filters; long-range black, used in electronic scanners and separation software; UCR black; or GCR black.
Blank—Most commonly, an undecorated face. May also refer to a sign face without any framing or cabinet.
Bleed—In screen printing, the portion of the job that extends beyond the area of the finished print.
Block Colors—Colors printed without gradations, tints or shades.
Blockout—Specially formulated paint used to block out the crossover connections between neon letters. Also a liquid type of mask used to seal holes in the stencil in areas not intended to be screen printed.
Bombarding—The process of heating the glass and metal portions of a neon tube to a high temperature to release all absorbed gases and other impurities.
Bonderized—A process where sheet metal is zinc-coated, then treated to allow for paint to adhere. Used in creating baked enamel signs.
Bounding Box—The area of an on-screen image at its maximum X and Y axes measurements. Altering the bounding box by moving its control points can change the shape or size of an image. Bounding boxes allows scaling of all graphics images in PostScript file types.
Braille—A form of tactile signage consisting of raised symbols that enabling visually-impaired and unsighted people to read and write. Braille is broken into two grades: Grade 1 Braille involves a character-by-character translation of printed material; Grade 2 Braille uses special contractions (much like the phonetic parts of speech) for messages. Grade 2 Braille is required by federal law according to the Americans with Disabilities Act (ADA).
Brightness—A measurement of the reflective quality of a medium such as paper or vinyl. Different brightness levels can cause changes in the appearance of color on the medium, and may require printer adjustment.
Broadcast Folder—A folder on the broadcast server machine in which published files are received for subsequent broadcast transmission.
Broadcast Server—A machine that prepares and transmits broadcast files received from a network manager machine. Also may refer to the broadcasting software that runs on this machine, or the network manager definition of the machine’s location.
Browser—Software for viewing Web sites, HTML files, and related content, such as Microsoft Internet Explorer.
Bulletin Colors—Specially prepared enamel paints preferred by many sign painters for hand-lettering.
Burning-In—Recommended to bring a neon tube to its proper brilliance, burning-in involves connecting the completed tube to a transformer similar to that which will be used in the installation and allowing it to remain lighted until proper brightness, color and electrical properties are achieved. Also called aging.
Burnish—To polish by rubbing, a common practice in the gilding process.
Byte—The basic unit of computer storage, comprising eight bits. Typically, a byte can store one character of text, or one pixel.
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Cabinet—An electric sign, not including the components and structure. A cabinet is made up of a face and back, or two faces, along with the edge. (Also called can.)
CAD (Computer-Aided Design)—The use of computer programs and systems to design detailed two- or three-dimensional models of physical objects, such as mechanical parts, buildings, and signs.
Calendered Vinyl—Vinyl sheeting squeezed between a series of heated rollers (also extruded) to achieve a small-enough thickness for cutting with a knife plotter. Calendered film is generally thicker and less expensive than cast vinyl.
Calibration—Operation of matching color shades and hues between any input devise(design software/monitor/scanner/camera) and output device (printer). Also the operation of keeping colors consistent during printer operations, compensating for changes in humidity, media, toners, etc.
CAM (Computer-Aided Manufacturing)—The process of using specialized computers to control, monitor, and adjust tools and machinery in manufacturing.
Candela—A unit of measure indicating the amount of intensity displayed by artificial light. Abbreviated as cd.
Capacitor—An electric circuit element used to store charge temporarily, consisting in general of two metallic plates separated and insulated from each other by a dielectric. Also called condenser.
Captive Audience Networks—A captive audience network is a digital advertising media network installed where your target audience is assured to remain in place for a period of time. Typical captive audience networks are installed in supermarket queues, gas station pumps, banks, and wherever people gather and wait.
Carrier—Substance in which pigments in inks are suspended. Aqueous, solvent and eco-solvent carriers evaporate after printing. Monomers are considered carriers in UV-curing inks, but are transformed into solid polymers after curing.
Carrier Sheet—Generally, a backing material used to temporarily hold or protect another material.
Cast Acrylic—Acrylic sheet produced by pouring acrylic resins into a mold and allowing them to cool. (See also Extruded acrylic). Yields best results from laser engraving.
Cast Vinyl—A type of vinyl film formed by spreading a molten plastic mixture on a carrier sheet in a thin layer, and then baking at high temperatures to remove solvents and fuse the remaining material into a film. Cast film is usually thinner, more pliable and more-expensive than calendered vinyl.
Casting—A method for mass-producing objects such as sculptures, letters, embellishments or individual signs by pouring liquid material into a prepared mold.
CAT5 Cable—A data and communications cable adopted by the Telecommunications Industry Association (TIA) and International Standards Organization (ISO). This version of Category 5 uses all four pairs of wires to both send and receive.
Cationic UV-Curing—A form of UV-curing ink chemistry. Cationic inks are said to adhere to an extremely wide range of substrates. Unlike free radical UV-curing, with cationic UV curing the cure reaction continues to completion even after exposure to UV energy has ceased.
CCD (Charged Couple Device)—A device made up of semiconductors arranged in such a way that the electric charge output of one semiconductor charges an adjacent one. The light-sensitive element inside many flatbed scanners. CCD-based scanners typically have 1,000-7,000 elements.
Channel—In electronic digital signage, a channel is a script that has been published in such a way that when its contents change, the updated material is forwarded to machines running the viewer that have subscribed to the channel.
Channel Letter—The outline of a letter, with extended sidewalls that create depth, into which a light source is placed.
Character Generator—A device for creating text on video. Character generators are often used to make information channels and electronic bulletin boards for TV and Cable.
Chase—The illusion of movement in neon tubes or incandescent bulbs created by turning the light sources on and off in sequence. Also, to decorate metal, typically by engraving or cutting.
Chromaticity—The quality of a color as determined by its purity and dominant wavelength, which is relative to saturation and hue, as used in the HSV model.
Chrome—High-quality positive color film, ordinarily shot by professionals. It includes 35-mm slides, 2 1/4" x 2 1/4" medium-format film and 4" x 5" view-camera transparencies. Chrome positives are often used for proofing.
Chrominance—The property of a color that describes its saturation, intensity, or colorfulness, used in differentiating two colors of equal brightness and hue.
CIE (Commission Internationale de l’Eclairage)—A color-standards organization based in Vienna, Austria. The CIE’s chromaticity diagram is a two-dimensional reference for defining colors and color spaces based upon physiological measurements of human color vision. An abbreviation for the CIE L*a*b* (CIELAB) color space.
Cladding—Cover material applied over the framework of a structure.
Classic Glass—Tubing used for neon signs or artwork in which the glass itself is colored achieving a deep, saturated color not possible with clear glass and phosphor coatings; typically a soda-lime based glass.
Clip—A predefined graphic image, such as a picture, drawing, symbol, etc., that can be imported and positioned on a background.
Clip Art—Ready-made, royalty-free pieces of printed or computerized graphic art.
Clogging—The result of dried ink molecules in an inkjet printhead. Although some clogging is typical with inkjet printers and is rectified by following a cleaning procedure, prolonged or severe clogging may result in the printhead having to be replaced.
Closed-Circuit Television—Traditionally, a private television network that is broadcasted internally within an organization. Modern narrowcasting solutions work over the Internet, deploying custom video and messaging anywhere in the world.
CLUT (Color Look Up Table)—A digital color-processing tool for converting color from one color space or device to another, such as from RGB (scale, 0–255) to CMYK (0–100%).
CMYK (Cyan, Magenta, Yellow, Black)—The four process colors used in most analog and digital printing systems. Black is called “K” because in process printing black is the key plate or keyline color.
CNC (Computer Numeric Control)—Communications language used in some robotics and larger machine-controlled cutting devices such as computerized routers, industrial mills and lathes.
Coat-Out—To paint the surface before the art is applied.
Codec—A software module responsible for compressing and/or decompressing an encoded media format such as AVI digital video.
Cold Cathode—The technical name for all forms of neon lighting. The term “cold cathode” is used to refer to 18mm to 25mm tubing operating at currents 60mA to 240mA. These gas discharge lamps also have electrodes that depend on a large emission surface area rather than high temperature for their operation.
Color Calibration—Hardware and/or software that allows a color match to be made between multiple digital devices.
Color Curve—Visual control used in photo-illustration and other graphics software to display color measurements and make tonal changes to an image.
Color Gamut—The range and scope of colors that can be reproduced by a specific display or output or display device, or by a method of color representation (such as RGB or CMYK).
Colorimeter—An optical device that measures absorbance of light by filtering reflected light into regions of red, green and blue. While dedicated colorimeters do exist, most instruments are actually spectrophotometers that compute colorimetric values based on spectral reflectance or transmittance curves.
Color Management—Refers to coordination of color with output and display. In output, color management is often handled on a device-by-device basis by imaging production software. See also RIP.
Color Modes—Models of tones based upon different values, such as: hue, saturation and luminance (HSL); hue, saturation and brightness (HSB); hue, saturation and value (HSV); red, green, and blue (RGB); and cyan, magenta, yellow and black (CMYK).
Color Separation—Color separations consist of artwork that has been split into component plates of cyan, magenta, yellow and black in preparation for process printing (CMYK), or into the required number of plates for spot color printing. Each separation prints a single process or spot color. Digital files can be composite separations (all information in one file) or pre-separated (each color on its own page).
Color Space—The set or model of how a device organizes color, assigning some formula—such as numeric values—as a way of replicating color. Examples of color spaces are RGB, CMY (without K, or black), and HSV.
Color Specification—Color values used to numerically specify a color within a color system.
Color Wheel—Arrangement of the visible spectrum of electromagnetic radiation (color) in a circular fashion so that the primary colors (red, yellow, blue) are located 180 degrees from the secondary colors that complement them (green, violet, orange, respectively).
Colorant—Colored material, such as including pigments, dyes or toners, that are mixed with a carrier to create inks.
Conduit—A metal or PVC plastic tube for protecting electric cables.
Content—In electronic digital signage, content consists of any files that are played back on video screens, including graphics files, sound files, video files, data feeds and script files.
Content Management—In digital signage, the act of controlling the flow and updating of the content of networked signage.
Continuous Inkjet—Process where ink is pumped through inkjet printing nozzles at a steady pace. Droplets are either shot onto a substrate/material, or electrically charged and deflected away from the printable surface and into a collection system.
Continuous Tone—Method of printing where color dots of equal size are placed in a variable-spaced pattern, creating the effect of a more-natural color look to an image; a direct result of stochastic screening.
Contour Cut—With vinyl cutters and print-and-cut digital printing devices, the ability to cut around the outlines of an image, both on the outer border and along any internal closed-loop borders.
Crosslink—In UV-curing, a term describing the chemical process by which the liquid ink is converted to a less-fluid, firmer, solid after exposure to a source of ultra violate light.
Contrast—In graphic design, the use of dissimilar or opposing elements, such as light and dark areas. Also, a term describing the difference between elements within an image in terms of their relative lightness and dark.
Control Frame—In electronic digital signage, the frame of the network manager window, from which you choose which network manager screen to work in.
Control Point—A connection between two line/arc segments or a selectable handle on a bounding box. Moving a control point changes the shape of an object, altering a line path, shape or size.
Control Console—In electronic signage, the device that receives information entered on a keyboard by the operator and transfers that information to the sign’s message controller.
Coordinate—A point that can be referenced by its position on the X, Y, or Z axes. The use of line or arc segments to connect coordinates creates paths for knives or bits to follow when cutting or routing an image.
Corona Treatment—Process that alters static charge of sheeting, especially corrugated plastic, for greater adherence of media such as ink for decoration.
Corrugated Board—A board created by gluing a corrugated piece to a flat face, or between two flat faces.
Counter—In a given typeface, any completely or partially enclosed area of a letter.
Cove Lighting—A type of indirect decorative illumination created by placing a lighting source inside a trough or cove to produce a halo effect.
Coverage—The area (usually given in square feet) that a given material will coat-out.
Crawltext—In electronic digital signage, the segment of text that moves through a text crawl element box.
Craze—Thin cracks or breaks in paint, plastic or vinyl, caused mainly by weathering, though it may also be caused by the incompatibility of paint layers or solvents.
Cross Bar—A horizontal arm that is attached to a sign. The cross bar typically runs perpendicular to the sign’s face and parallel to the building’s facade. It is used with guy wires to help stabilize building-mounted signs.
Crossover—The connection between two portions of a neon tube, intended to be unnoticed in the finished sign. Typically, crossovers are coated with blockout paint.
Curing—The process of effecting a chemical change in some inks or paints by the application of heat or ultraviolet light.
Current—The flux or rate of flow of electrical charge carriers in a conductor. A unit of current is typically given in amperes or milliamps (mA).
Cut-Outs—Lettering or graphics that are cut from another material, then attached to the sign face to provide depth.
Cyclohexanone—A petro-chemical solvent solution. In inkjet printing, it is commonly used as the main carrier in solvent inks. Cyclohexanone is rated by the EPA as a hazardous material containing high levels of harmful VOCs. Mild-solvent (or light solvent) inks contain lower levels of the substance, but still contain VOCs. Fumes from cyclohexanone are managed through proper ventilation or air-scrubbing systems.
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Dark Hardening—The continuation of the crosslinking process in UV-curing inks even after exposure to an ultraviolet energy source has ceased. Also called dark cure, or post cure hardening. A feature of cationic UV-curing inks.
Datacasting— Broadcast of digital information over networks to receivers and media players. Datacasting is sometimes used as an alternative to traditional video broadcasting, because the receivers and player units can have the “intelligence” to customize their playback programming for the location and intended audience. The system of receivers set up to receive messages from a particular datacast are known as datacasting networks, which are a venue for advertisers.
Deboss—The process of producing depressed letters, particularly those produced by engraving dies or plates.
Decal—Copy and/or graphics printed on a PSA film, then cut to a specified shape.
Decompress—The process of expanding a compressed file to its original uncompressed form..
Definition—The amount of contrast between a sign’s art and background.
Delamination—The separation of layers in a laminated substrate. Delamination is most often caused when edges are over-exposed to moisture, temperature extremes or UV light, resulting in adhesive failure.
Delta-E (∆E)—The measurement unit, in a uniform color space, of the perceivable differences in color viewable by the human eye. The first noticeable change is 1 ∆E. Delta-E measurement is used, for example, by customers specifying and accepting color, and in manufacturer guarantees of colorfastness.
Densitometer—Device that measures the absorption of light in a color, based more on how it reacts to the printed piece than the response of the human eye. Used to check color proofs and coordinate colors between output devices and displays, but measurements remain specific to materials and inks/toners.
Density—In sign making, a measurement used to express the hardness of foam boards in pounds-per-cubic-foot.
Descender—In a given typeface, the portions of the lowercase letters g,j,p,q,y and sometimes the uppercase letter J that extend below the baseline.
Device-Independent Color—A color-matching system that relies on a universal set of values, rather than utilizing the color gamut of a given piece of equipment.
Design Menu—In digital signage, a menu providing access to all the text or graphics utilities that can be used when composing a page for digital content.
Die-Cut—A cut made with a steel rule die manufactured to cut a particular shape, commonly, when a large number of shapes with curved lines are to be cut. Also refers to the object that has been cut.
Diffusion Pump—A vacuum pump consisting of a boiler, a jet assembly and a cooling chamber, designed to increase the speed of evacuation of a neon tube after bombarding.
Digital Media Network—The term digital media network can refer to anything from multiple web sites, to multiple television stations being centrally owned and operated. With the reduction in cost of custom controllable media players, a new breed of digital media network is emerging, known under many different terms. The industry appears to be settling on the term electronic digital signage to describe these new digital media networks, where custom images are digitally delivered to sign-like devices located throughout retail environments, or the enterprise.
Digital Multimedia Broadcast—The process of broadcasting multimedia over the Internet, or satellite, to be tuned in by multimedia receivers, or media players, capable of playing back the multimedia program. Through a process called multicast, a single broadcast can send programming to thousands of receivers, which can play back the content individualized to the location. This is one of the advantages of multimedia broadcasting over traditional video broadcasting.
Digital Printer—A printing device that is capable of translating digital data into hardcopy output. Technologies employed in digital printers include inkjet, thermal transfer, electrostatic and laser photo-imaging.
Digital Video—A video that has been digitized so that it can be controlled from a PC and displayed directly on a computer monitor.
Diode—A solid-state device that allows electrical current to pass through it in only one direction. Think of it as a one-way valve for electrons.
Direct Current (DC)—One of three varieties of electricity. Specifically, a current that always flows in one direction, around and around, as in the electricity that powers household batteries. See also Alternating Current.
Directional Sign—Signs designed to provide direction to travelers. The Highway Beautification Act sets guidelines for the size, placement and content of true directional signs.
Directly Illuminated—A sign that is illuminated by a source other than ambient light; any lighted sign.
Directory Sign—An on-premise sign that identifies the names and locations of tenants in a multi-tenant building, or group of buildings.
DirectX—Microsoft’s universal graphics driver software for Windows 95/98 and Windows NT PCs. Some software depends on DirectX for it graphics playback functions, thus DirectX must be present on any PC that plays back some scripts.
Dirty Color—A color made from four or more pigments.
Dithering—A process that simulates color variations or shades of gray by alternating the sizes and shapes of pixel groupings. This reduces the contrast between dots of different colors/shades and creates a more-flowing, natural look. An alternative to halftone.
Dmin/Dmax—Measurement of the density of a printed image; to be exact, ability of a tone to absorb light. Dmin is the lowest density measurement, while Dmax is the highest. The Dmin/Dmax scale is 0-6, although a pure carbon black is 4 and most printers register a slightly lower measurement for blackest black.
DM/PL—Programming instructions language used to connect a plotter with a computer. DM/PL is used in software drivers from some sign programs.
DOD (Drop On Demand)—Piezo printhead technology in which inkjet nozzles fire ink only when color is needed, instead of firing ink continuously and being deflected away from the substrate when not needed, as in continuous inkjet systems.
DOOH (Digital Out Of Home Advertising)—refers to that portion of advertising delivered in locations other than the home. Primary examples include billboards, movie theaters, and gas stations.
Dot Gain—Effect produced when individual dots of color (as with an inkjet droplet) spread and become larger than their intended size, resulting in the darkening of a printed image.
DPI (Dots Per Inch)—A unit of measure used to describe the resolution capability of a given piece of equipment by measuring the number of individual dots the device can reproduce in a linear inch. If the horizontal and vertical resolutions are different, typically both figures will be given. The higher the number of dots, the less easy it is to distinguish individual dots, making the image sharper.
Double Tube—Two neon tubes running parallel to each other, often used for outlining or borders.
Double Face—A sign with two parallel but opposing faces.
Drag Knife—A cutting edge mounted to turn freely. With sign plotters, the combined movements of the plotter head along the Y axis and the vinyl/medium along the X axis causes the knife blade to turn to create straight lines and curves.
Draw—The depth of the shaped letter or face from the original plane in the manufacture of plastic letters and sign faces by embossing, debossing, or vacuum-forming.
Drawing Program—An application, often called a structured or vector drawing program, used to create and manipulate two-dimensional images and shapes as independent objects, as opposed to bitmap images.
Dress—To prepare or put in a finished condition. In sign making, the faces, edges and corners of a sign and its art may all be dressed.
Driver—Power supply for LED systems, providing low voltage output.
Drum Scanner—Device utilizing a rotating drum, which artwork is mounted on. As the drum spins, light from the image enters a lens, allowing the image to be recorded in data as a series of fine lines. Because a drum scanner can record more digital information, it typically allows for easier image manipulation and a more detailed printed image.
Dye—An organic-based colorant that may be dissolved in a liquid; esp., dye-based ink. Dye particles are much smaller than pigment particles.
Dye Sublimation—Imaging process where colorants are vaporized with heat and pressure, and deposited on to a substrate to create an image. Typically it is a transfer process used in polyester-based fabric printing. Sublimation inks are mirror-printed on a donor material (transfer paper). The image is then sublimated onto the fabric using a heat press.
Dynamic Digital Signage (DDS)—(See Electronic Digital Signage)
Dynamic Range—Measurement of contrast from highlight to shadow; in some cases, the number of shades per primary color (see RGB). Considered one of best ways to compare true ability of a scanner, although not all manufacturers measure and release figures on it.
Dynamic Visual Messaging—The process of using animated graphic design to communicate to target audiences through signs and public displays.
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Eco-Solvent Inks—Inks using a less-toxic solvent-based carrier. Printers using eco-solvent inks emit less harmful VOCs (volatile organic compounds).
Edge—The part of the sign that encloses the back and face or faces. The frame.
Electrode—A terminal that conducts an electrical current between two conducting substances. Electrodes are found at both ends of a neon unit.
Electrolytic Capacitor—A type of capacitor that has a lot of capacity for its size and price. It contains an electrolyte than can dry out over time and that in turn decreases its capacity. Every 10C increase in operating temperature reduces the rated life of the capacitor by half. A 20C high temperature decreases life to 1/4.
Electronic Digital Signage—A form of signage using plasma display panels (PDPs), liquid crystal displays (LCDs), light emitting diode signs (LEDs), and/or television (CRTs) in place of traditional signage. Content can be instantly updated, and multiple screens can be networked and managed from a single location.
Electronic Digital Signage Network (DSN)—Delivery system for retail media, outdoor advertising and placed-based television content in public spaces, consisting of displays, software and hardware tied together through a computer network infrastructure. (Also known as dynamic digital signage; digital sign system, etc.)
Electronic Display—A general term referring to any type of electronic programmable display.
Electronic Message Center (EMC)—A sign that utilizes computer-generated messages or some other electronic means of changing copy. These signs include displays using incandescent lamps, LEDs, LCDs or a flipper matrix. Also called changeable message signs (CMS).
Electrostatic Printer—A printing device based on xerography (the technology used in most photo copiers). Electrostatic printers (also called e-stat) transfer toner resins or dyes from an electrically charged plate or writing nib to a substrate, then thermally sets them.
Electronic Kiosks—Terminals that disseminate information and services to the public through touch-screens and video displays. Electronic kiosks are often built by display companies and customized to individual needs by multimedia developers and value added resellers. They often incorporate card readers, coupon printers, and other devices specific to their application.
Embellishments—Elements added to a sign face for aesthetics and visibility. Cut-outs, push-throughs, neon strips and clocks are all examples of embellishments.
Emboss—The process of producing raised letters, particularly those produced by engraving dies or plates.
Emulsion—A semi-liquid material that dries hard and is used in preparing stencils used in screen printing.
Enamel—a type of paint, usually opaque, that dries to a hard glossy finish.
Enclosure—A piece of equipment which houses the components, such as a monitor or display, and in some cases a computing device and/or other option peripherals devices such as printers, keyboards, etc.
Engraving—Method of marking metal, plastic or glass in shallow, negative relief utilizing a bit or graver. Engraving may be done freehand, using a pantograph or computer-driven equipment.
EPS (Encapsulated PostScript)—File type that allows different information, such as colors and fill patterns, to be carried between software programs. Files can include bitmap and vector information, including low-resolution files for thumbnail previews. Versions of this include variations from Adobe Illustrator (with .AI filename extensions for DOS and Windows).
Equalization—A processing technique where the range of colors in a file is expanded to produce a better image.
Error Diffusion—Process where equal-size dots are placed, via computer calculation, based on an image’s detail and tones. The result is a continuous tone image.
Event—An action in a script; virtually everything that happens in a script is an event, including text, sounds, wipes, animations, etc.
Expanded-Gamut Color—A system in which additional colors (usually light cyan, light magenta, light yellow, light black, green and/or orange) are used to supplement CMYK, in order to reproduce a greater number of colors. See also Hexachrome, hi-fi color.
Extender—Added to an ink to improve its working quality or for extending the volume.
Exterior Illumination—Illumination that is provided from a source separate from the sign itself, such as a spotlight. Also called indirectly illuminated.
Extruded Acrylic—Acrylic produced by forcing acrylic resins through a specifically shaped die (see also Cast Acrylic). Usually avoided by laser engravers since it cuts well with a laser engraver but does not engrave well.
Extrusion—A part created by forcing a raw material (usually metal or plastic) through a die to create a specific shape.
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Facade—The front or principal entrance of a building.
Face—The decorated surface of a sign; the area on which the copy and art is placed.
Fiber Optic Display—A type of sign that transmits its message utilizing light directed through fiber optic cable.
File Compression—The process of condensing a file, video, or animation using special hardware and/or software so that it requires less storage space. In color management, the ability of a software to reduce the range of colors in an image to whatever can be reproduced on an output device is called “compression”.
Fills—Tool-path directions and methods for traveling through substrate to remove, or rout, material. Sweep or hatch fills remove material in consecutive, side-by-side lines; spiral fills trace the edge of area of material to be removed, then work inward to center in one path; island fills trace the edge, then work inward in separate, concentric paths.
Flasher—A mechanical device designed to interrupt the electrical current in a sign at regular intervals, turning the light source on and off to create a flashing image.
Flat—In hand-painted signage, a brush made with medium-length ox hair bristles; called a flat because the bristles are cut flat and tend to remain that way when pressed to its full width; useful in maintaining even stroke widths. Flat sometimes refers to rigid substrates, particularly metal and plastic sheets, as they are received from the supplier; an undecorated substrate. In addition, the term describes a finish that is duller than matte, and has little reflective quality.
Flat Panel Display—Refers to using flat panel electronic display devices, such as liquid crystal displays (LCDs) or plasma screen in place of traditional signs.
Flatbed Printer—A digital printer designed to accommodate and print directly to various thicknesses of flat materials and sheet substrates.
Flexible-Face Material—Translucent material, usually decorated and then stretched across a frame to form awnings, billboards and other types of signage.
Flexible Metallic Tubing—A flexible conduit tube used to protect electric wiring.
Flipper—A disk, door, cube or sphere that opens and closes electromagnetically, showing a colored or black surface used in some electronic changeable copy signs.
Flood Stroke—In screen printing, inking the image areas of the screen between printing strokes.
Foam Board—A type of lightweight, rigid board used for interior signs. Foam boards consist of a foam center sheet laminated on one or both sides by a variety of substrates.
Focal Length—A term used to refer to the size or type of lens used in a laser engraver. Usually between 1” and 3”. Different focal lengths determine the size of the “dot” the laser will engrave each times it fires.
Focal Point—The spot in a design or layout that first catches the eye. In good design, the focal point and the main message the sign seeks to convey will be the same thing.
Foil—A donor sheet of color used in thermal transfer printing.
Font - Font refers to a single style of a particular typeface, but, since the advent of the computer and scalable fonts, not its size. For example, Bulmer regular, Bulmer italic, Bulmer bold and Bulmer bold italic are four fonts, but one typeface.
Footing—The (usually) concrete supporting base of a structure, as for a pylon or monument sign. Also called “footer”.
Force—The downward pressure made by a plotter on a blade tip to ease cutting through materials. Also, a measurable influence tending to cause movement with a sign, such as wind or gravity.
Format—The workable space within which the art and copy must fit. Also, the shape and area of a sign face. Also, the type of software program in which a file is stored (ie. jpeg, pdf, eps, gif, bmp, etc.)
Formed—Refers to a plastic face or letter that has been heated and shaped to give it dimension.
Four-Color Process—Any printing method that utilizes the subtractive primaries plus black to create the illusion of different colors.
Frames Per Second (FPS)—the speed at which an animation, film or video is displayed. The frames per second setting for an animation should be at least 12 to create the illusion of movement.
Free Radical UV Curing—The most common form of UV-curing ink chemistry, it employs a free radical reaction whereby a photoinitiator absorbs UV energy and generates an unpaired electron, beginning a chemical chain reaction (crosslink) with a double bond substance (monomers), causing the polymerization of UV ink. In free radical UV curing, the reaction ceases once the ink is no longer exposed to UV energy.
Friction Feed—Process where material is fed through a printer or plotter by placing it between a motor-driven grit wheel and two tensioned pinch rollers.
FTP (File Transfer Protocol)—A standard protocol for transferring data over the Internet. To use FTP, FTP software must be set up on both sending and receiving ends of an FTP transmission, and the client (initiator) must have a username, password and a valid target address on the server.
FTP Server—A computer that can receive requests for an FTP link from a client machine, or the software on that machine that allows it to do so. This includes FTP server capability. Also called an FTP host. See also IIS.
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Galvanized—Steel or iron that has been protected by a zinc coating.
Galvanic Isolation—No electrically conductive path from the AC input to the DC output. This is a safety feature to prevent shock should a person come in contact with a broken LED in a sign.
Gamma—Measurement of the degree of contrast between the lightest and darkest tones of an image. Gamma is also noted as the slope of a curve in measurements of color values, and can be altered for display and output.
Gamut Compression—Electronic editing of an image so that it can be displayed or output within the limits of a particular device.
Gantry—Bridge on which the spindle assembly of certain computerized routers and engravers travels. The spindle usually travels along the length of the gantry for X-axis movement. The gantry may also be mounted on rails for movement along the Y-axis; with other machines, the gantry is stationary and the table itself moves along the Y-axis. This term is also used in inkjet printing to describe the bridge on which a scanning printhead assemblies is housed on certain flatbed printers.
Gauge—A method for measuring the thickness of sheet metal. In the sign industry, most sheet metal ranges from 10-26 gauge.
GCR (Gray Component Replacement)—This is a color separation process in which black ink is used to replace cyan, magenta, and yellow (CMY) in mid-tone and highlight areas where the three inks overlap, in order to reduce ink consumption and drying time. Similar to UCR.
Genlock—In electronic digital signage, a video device that synchronizes two video signals and enables them to be mixed; for example, to overlay a subtitle produced on the computer onto live video.
Gilding—The application of thin metal sheets to glass and other surfaces. See also Gold Leaf.
Glass Sleeves—On some neon tube installations, clear glass units designed to add insulation to the electrodes and other wiring.
Gold Leaf—Gold manufactured into thin leaves, commonly available in a range of from 10-23 karats.
Gradation—Transition between colors or shades, created by mixing percentages of a dominant and secondary color and then altering them in steps to create the change.
Grit Wheel—The motor-driven roller that moves material through a friction-feed plotter.
Grommet—A reinforced metal eyelet found in banners used to receive cords or other fasteners.
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Halation—A spreading or reflection of light, a halo-like effect, produced by cove lighting or reverse channel letters.
Halftone—The process of converting images into dots of various sizes with equal spacing between centers.
Halo—A ring of light. Usually refers to the reflection of light achieved by reverse channel letters, which appear to be ringed by light because the light source is reflecting on the background from which the letters are pegged-out.
HDPE (High-Density Polyethylene)—A strong, relatively opaque form of polyethylene having a dense structure.
HDU (High-Density Urethane)—A type of hard foam product used in sign production. Urethane has the density and fabrication characteristics of wood, but only one-third of the weight.
Head-End—An installation that is the final point from which video feeds for multiple channels are sent to broadcast or cable television customers. In addition to transmitting equipment, a head-end can contain feeds for various channels.
Header—A separate board above the rest of a sign that gives it a headline or contains a different advertising message for the same product. Most often seen with point-of-purchase advertising.
Heat-activated Adhesive—A type of adhesive used on some film laminates that is not sticky at room temperature but softens when heated, thus activating the adhesive.
Heat Bending—The process of heating PVC boards and then bending them to desired shapes.
Heat Sink—A piece of thermally conductive material attached to a semiconductor or other electronic device (such as an LED), to conduct heat away from the device.
Heat Transfer—A type of color imprinting that uses a specially coated paper that is printed in a special printer (often a laser printer) that can be applied to fabric or other substrates using a heat press. Not to be confused with sublimation or lamination.
Hertz (Hz)—In electronics, a measurement of signal frequency. Hertz are referred to in a computer’s CPU speed, or a monitor’s refresh rate. The CPUs in personal computers recently passed from being measured in megahertz (MHz) to being measured in gigahertz (GHz). Monitor refresh rates are most frequently measured in kilohertz (KHz).
Hexachrome—Color matching system created by Pantone Inc. for combining six colors to create a larger reproducible color gamut.
Hi-Fi Color — Any process—such as stochastic screening or six-color printing—that expands the possible color gamut beyond four-color process.
Highlight White—Printing application in which white ink is used to enhance an image, sharpen colors or add contrast.
Hinging—Vinyl installation process where a cut vinyl image, the carrier liner and the transfer tape are placed on the target surface; a piece of masking tape is then attached to the top edge of the transfer tape. The liner is then slowly rolled off from the top edge, and the transfer tape and vinyl image are slowly smoothed onto the surface. A variation of this is to leave an exposed strip of transfer tape above the top edge of the liner, instead of a separate piece of masking tape, to act as the hinge.
Histogram—Graph showing the number of pixels showing up at different brightness levels of an image.
Housing—For neon tubing, made from porcelain or Pyrex glass, a housing mounted in the sign that provides the contact between the electrode and the lead-in wire.
HSB (Hue, Saturation and Brightness)—a hue-based color space model that is widely used to select colors within image editing and other graphics applications. This definition is often expressed geometrically as an inverted cone and double cone.
HSL (Hue, Saturation and Luminance)—A hue-based color space model that defines color using a double hexcone. This definition is often expressed geometrically as an inverted cone and double cone.
HSV (Hue, Saturation and Value)—A color model that refers to a color space or color definition. Hue involves wavelength; saturation is the percentage of white with zero-percent noting pure color; and value is the brightness, with zero-percent representing solid black.
HTML (Hypertext Markup Language)—The programming language used to create Web pages for display in Web browsers. HTML can be created directly with text editors or Web publishing programs, such as DreamWeaver, or it can be the output of other programs that make dynamic Web pages on the fly. When you select “view source” from your Web browser, the code that you are viewing is HTML.
Hue—The property of color that indicates the color name, such as purple, blue, or green, that can be specified by particular wavelengths or by CIE coordinates. It ranges from 0-360, but is normalized to 0-100% in some applications.
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ICC (International Color Consortium)—A group of industry vendors (formed in 1993) whose goal is to create a standardized color management system that functions transparently across all operating systems and software packages.
ICC Profile—A standardized description of the color attributes of a particular substrate, ink, digital printer or imaging device which was set by the ICC. A profile is created by defining a map between the source and target color space using a profile connection space, either a L*a*b* or CIE color space.
Image Processing—Enhancing and manipulating an image, such as by adjusting its size, resolution, or color palette.
Inflatables—Plastic signage that assumes a three-dimensional shape when filled with air under pressure or helium gas.
Initiation—In UV-curing ink chemistry, the beginning of the cascading effect or chain reaction caused by the photoinitiator as it combines with a double bond (free radical UV curing), or as it opens the epoxide ring (cationic UV curing) of the monomer, to ultimately change the liquid monomer to a solid (polymer) state.
Inkjet Ink—The mixture of colored pigments or dyes in a suitable liquid used for digital printing. Typically either water-based, solvent-based, or UV-curable, inkjet inks dry or are cured to form a solid colored surface.
Inkjet Printer—Device that drops liquid ink onto a substrate for printing. The thermal bubble-type of inkjet heats ink to approximately 400 degrees F inside a small chamber before shooting it through a series of nozzles. A piezo-based inkjet puts ink in a small chamber and then sends a charge to contract piezoelectric crystal lining the chamber and send the ink through the nozzles.
Ink-Receptive—Describes a substrate that can be made wet by ink when printed and that will bond with the ink after drying or curing.
Installed Content Folder—In electronic digital signage, it is a folder on the media player for content files that has been placed on the machine by some method other than being sent by the network manager, or downloaded by a separate application, for example. See also Content Folder.
Intensity—The density or opaqueness of a color. Also, the amount of light put out by a lamp.
Interactive Kiosks—Usually free-standing information displays that allow users to retrieve information through touch-screens, buttons, and video displays. Interactive kiosks are frequently controlled by computers running software written with multimedia authoring software.
Interlace—In electronic digital signage, a process used to refresh video displays and some computer displays that alternately scans every other horizontal scan line in the display. Interlaced displays often flicker, especially when showing static images containing narrow horizontal lines.
Internally Illuminated—A sign which is lighted through the use of internal electric fixtures or lamp-banks. See also Backlit Sign and Exterior Illumination.
Interpolation—Any mathematical averaging technique used to increase the size of an image file by creating more pixels, used to increase tonal value and apparent resolution.
Interpolation—Process for increasing resolution of an image by creating new pixels via an averaging of the size and colors of surrounding pixels. The result is more dots-per-inch (dpi) in resolution, although some sharpness may be lost.
Internet Service Provider (ISP)—A company that provides Web hosting, FTP hosting, e-mail and other internet services.
Interrupt Scheduling—In electronic digital signage, a type of scheduling for pages that causes a scheduled page to play at a precise time, interrupting any other script activity currently occurring.
Invariant Color—A color that isn’t altered by changes in illumination.
IP Address—an address in four-part numerical format that uniquely identifies a computer accessible over a TCP/IP-based LAN or the Internet. For example, 127.0.0.10.
IP Multicast—(Internet Protocol Multicast) IP Multicast is a networking transmission protocol allowing multiple computers to simultaneously receive the same transmission. This is faster than sending an information packet to each individual computer, and is an efficient way to update many remote locations simultaneously. Each media player site is “tuned in” for the packets being sent by the broadcast server. IP Multicast is not limited to the Internet and terrestrial connections, but can also be broadcast over a satellite to be received by inexpensive VSAT dishes—often already part of a company’s infrastructure for their WAN.
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Jaggies—Refers to the stair-step appearance of the edges of digital images; created when the image resolution is too low.
Job—A command or series of to perform maintenance tasks on one or more media players. Jobs typically involve uploading and downloading scripts, log files, and media files.
Job File—A relatively small file that is created by network managerand placed in the job folder of each media player targeted by that job. The job file instructs the player on job tasks it should execute, such as downloading an updated script, deleting a file, instantly.
JPEG/JPG (Joint Photographic Experts Group)—A type of compressed computer file usually used when sending photographic images through the Internet.
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Kerning—The process of moving pairs of letters farther apart or closer together to make them appear more evenly spaced.
Kiosk—A small structure used for posting temporary signs and notices.
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L*a*b*—Color space calculated with values of lightness (L) and attributes of red-green (a) and yellow-blue (b). Most commonly associated with CIE for a non-device-dependent coordination of color. The two-dimensional reference defines colors and color spaces based upon physiological measurements of human color vision.
Lacquer—A quick-drying clear finishing material similar to varnish. May also be used as a binder.
Laminate—A process by which different materials are layered and then bonded together using adhesion. The end result may be the creation of a substrate—such as medium-density overlay (MDO)—or the protection of the underlying surface, as when a clear, plastic film is laminated to a decorated surface.
Laser—An intense light beam with a very narrow band width, used in engraving and other cutting equipment.
Laser Engraver—Device using a directed, amplified beam of light to cut and mark material. Laser engravers generally use one of two technologies; carbon-dioxide CO2 gas-based or Yttrium Aluminum Garnet (YAG) type lasers. Both will work with a variety of engravables, including glass, acrylic, phenolic and coated metals. YAG lasers can also perform deeper engraving and cutting of metals. The power of a laser engraver is measured in watts.
Layout—The total arrangement of a sign’s graphic and copy elements.
Latex Inks—A new type of water-borne inkjet inks developed by Hewlett-Packard designed for outdoor wide-format printing applications. The inks contain about 70 percent water, 30 percent co-solvents, pigments and latex polymer particles that form a film and bind with substrates with the application of heat. HP has developed a special inkjet printer for these inks.
LCD (Liquid Crystal Display)—Thin flat screen video displays commonly used for TV, computer monitors, wristwatches and electronic digital signage. LCDs contain two thin transparent surfaces (usually glass), with grooves full of a liquid crystal substance. Thin film transistors (TFTs) on the surface material apply an electric current to the liquid crystals. This current polarizes the crystals, making them twist and thus block light. When off, the liquid crystals go into random alignment and let light pass through.
LCD Panel—A portable display unit that is placed on top of an overhead projector and connected to a computer so that the computer’s display can be projected onto a large screen.
Lead-in Wire—The wire that connects an electrode to the power source.
LED (Light Emitting Diode)—A semiconductor diode that emits light when voltage is applied; a solid state lighting component, used in signage for EMCs, channel letter illumination, edge lighting glass or acrylic panels or for various decorative lighting effects.
LED Array UV Lamp—A special lighting system that uses a tightly packed array of light emitting diodes (LED) to produce high levels of ultraviolet (UV) light in order to cure UV-curable inks. Though not yet widely used in UV-curing inkjet printers, LED array technology offers low heat-emission, instant switching properties, long component life and high energy efficiency.
Lenticular Image—An image that shows depth and/or motion as the viewing angle changes; produced by overlaying specially printed interlaced images with a plastic lenticular sheet which is molded to form a series of lenses that coincide with the different parts of the interlaced images.
Letterheads—Loose-knit group of sign makers who seek to learn, share and pass on the techniques and craft of sign making.
Light Magenta/Light Cyan—Muted or diluted forms of the two primary colors. When added to regular CMYK, these shades provide for greater variety in printed dot color for more natural-looking continuous tone prints.
Light Reflectance Value—The amount of light reflected by a given color. For instance, yellow has a higher light reflectance value than purple. Abbreviated as LRV.
Linearization—The process of calibrating the tone values of a scanner or digital printer to create evenly distributed tones capable of rendering detail throughout an image.
Linear Scanner—A scanning device that uses a straight-line array CCD. The linear array captures one line of the image at a time as the CCD is moved over the entire image in steps.
Line Screen - Used to define the density of the screen, similar to dots-per-inch. A 200-line screen has a pattern of 200 halftone dots per inch. As with DPI, the higher the number, the greater the detail within the reproduction.
Linked Content—Content in digital signage that is referenced by a script, but is not sent as part of the script when that script is sent to content media players. Linked content can be updated at a separate time from normal script content or from an independent source.
Location Based Advertising—The placement of advertisements near an actionable location. In other words, location based advertising deals with strategically placing messaging near where buyer behavior can be most immediately influenced, and converted into a sale. This most often applies in retail settings, such as shopping malls.
Location Based Media—Refers to any public display media, such as signs, billboards and posters located out of home, usually near where the audience is near the point of purchase decision.
Lumen—A unit of measurement for light.
Luminance—Refers to the lightness or brightness of an image.
Luminescence—The quality of giving off light by the absorption of radiant energy. Used to describe any cold light.
Luminous Tube—A neon or fluorescent tube, consisting of a sealed gas-filled glass vacuum tube with an electrode at each end containing a specific gas. As an electrical current is passed between the electrodes, the gas is ionized and emits light.
LUT (Look Up Table)—Pre-set measurements and adjustments for different media, file types, printers, etc.; stored to ease imaging and printing operations. Sometimes included as part of a total RIP solution.
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Magnetic Sheeting—Magnetized strip laminated to a flexible plastic sheet and sold in rolls.
Magnetic Core—A material that can couple changing magnetic fields in a transformer. For AC line frequency transformers, they are most often made of thin pieces of Silicon Steel stacked to the needed height. For high frequency transformers the core is usually made of ferrite. A material often made from manganese-zinc or manganese nickel alloy.
Mahl Stick—A baton-like piece of wood with a knob at one end to provide extra support for a painter’s brush hand.
Manifold—In neon tube processing, a system of vacuum tight tubing arranged so that attached tubes can be evacuated with a vacuum system and filled with rare gases.
Marquee—In computer graphics, the process of using a mouse-driven cursor to draw a rectangle around an on-screen object, therefore selecting it for further work. Sometimes called highlighting in software packages. In architectural sign-making a marquee is a projecting structure permanently attached to, but not a part of the roof. Sometimes called a canopy.
Masking—In painting or screen printing, the process of covering—usually with tape or paper—areas to protect them from receiving subsequent layers of paint or ink.
Matrix—The number and amount of lighting units in the display area of a changeable message sign.
MCI (Media Control Interface)—The standard method of controlling multimedia devices before DirectShow/Windows 95. It is a standard for communicating with devices that support VCR-like operations like play, pause, stop, etc., such as MPEG playback cards. A given device might offer both MCI and DirectShow drivers.
MDO (Medium-Density Overlay)—An exterior-grade plywood with an average veneer on both sides.
Media Player—In electronic digital signage, an audio-visual component used to feed content to a television, LED or flat panel display for an electronic digital signage system. Also called “multimedia player.”
MEMS (Micro Electro-Mechanical System)—A manufacturing process done on an extremely small scale (typically involving components between 1 to 100 micrometers in size). In inkjet technology MEMS uses laser systems to cut and shape silicon to create printhead components such as jetting chambers, nozzles and nozzle plates. Typically, MEMS-based printheads feature more nozzles per inch and greater jetting accuracy.
Menu Board—A changeable point-of-purchase advertising display that allows the retailer to list products and prices.
Mercury—A heavy, silver-white metallic element liquid at room temperature. In neon tube processing, it may be mixed with rare gases, typically argon, to produce ultraviolet light.
Mesh—In screen printing, the material stretched across the frame. Also referred to as the fabric.
Message Center—Any sign that displays changeable copy through electronic or mechanical means.
Message Controller—In an electronic sign, the device that stores messages and conveys them to the display area.
Mercury Arc Lamp—A special lighting system designed to produce high levels of ultraviolet (UV) light in order to cure UV-curable inks. Most commonly used technology in UV-curing inkjet printers.
Metamerism—In color matching, a characteristic of prints in which color matches under one lighting condition, but not another.
Microprocessor—The main computing, or thinking chip in a computer.
Micro-Stepping—Process of moving media through a printer in smaller-than-standard motions. Can improve dot gain and density when printing solid areas on film positives.
Mild-Solvent Inks—Also known as “light solvent” inks, these use cyclohexanone, the same carrier employed in solvent inks, but in greatly reduced concentrations. Printers using mild-solvent inks employ additional carriers and emit fewer harmful VOCs than standard solvent inks.
Mirror/Mirror Print—Function of reversing type or an image to be printed. Used mainly for cutting jobs to be installed on the inside surface of a transparent substrate (such as a window). Often used in digital imaging as part of a process wherein a reversed image is applied to a transfer paper used in dye-sublimation transfer printing.
Moiré Pattern—A visual defect that occurs when the dots of the different separations used to create a halftone image are unevenly spaced, conflicting or have overlapping angles. Visual artifacts occurs between the dots of the different separations in the halftone images.
Monomer—A chemical compound ingredient in UV-curing inks that, when combined with other similar structures and oligomers and exposed to UV radiation, undergoes the process of polymerization and is transformed from a liquid (monomer) to a solid (polymer) state.
Monument Sign—A free-standing sign sitting directly on the ground or mounted on a low base.
MovieClip—a digital video segment in an ActiveMovie-supported format, such as AVI, QuickTime, or MPEG, that has been loaded as a clip. Movieclips are similar to animclips except that they can also have sound associated with them. Movieclips cannot have their frame rate or color palettes adjusted.
MPEG (Motion Picture Experts Group)—An industry group that developed a standardized form of file compression for digital video and audio sequences. MPEG digital video sacrifices some image quality to achieve very high compression.
MPEG-4—An updated file compression standard developed by MPEG which brings higher levels of interaction with content, controlled by the content developers. It also brings multimedia to new types of networks, including those employing relatively low bitrates, and mobile ones.
Multi-Color Printing—Any screen printing job involving the application of more than one color of ink.
Multimedia—The combination of various presentation media such as text, sound, graphics, animation, and video.
Multimedia Displays—TVs, plasma display panels, LCDs or other video display device delivering multimedia content, often connected to a computer and touch screen.
Multimedia Signs—Multimedia signs are a growing trend in the signage industry, where televisions or flat panel display devices such as plasma screens or liquid crystal displays, are turned into updatable signage. Advantages of multimedia signs include the ability to deliver messaging to targeted audiences depending on schedule or environmental conditions. For example, advertise umbrellas when it’s raining.
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Narrowcasting—Delivers highly targeted and customized messages to audiences in public locations at scheduled times. Usually, this is accomplished with a networked multimedia system allowing rapid production, customization, distribution, and playback to multiple locations on display devices such as televisions and liquid crystal displays. The advantages of narrowcasting over traditional media include lower production costs, greater flexibility, and more attention-grabbing visuals.
Narrowcasting Networks—Narrowcasting networks reach targeted portions of the public. They employ selective broadcasts of media-rich content to a variety of types of “receivers”. These receivers are typically some form of television, computer monitor, or flat screen display with a media player attached. They emulate the appearance of signs, billboards, and kiosks, located in prime locations for exposure to your desired demographics. These players can then be selectively updated with scheduled, rapidly produced, and rapidly adapted programming.
National Electric Code (NEC)—Electrical safety code adopted by many jurisdictions around the United States, published by the National Fire Protection Association.
Negative Space—The area around and within the art and copy. Also known as white space. See also Positive Space.
Neon—A rare inert gas which, when an electric current is discharged through it, produces a reddish-orange glow. The word neon is also often used synonymously to describe a type of luminous tube sign, which may contain other inert gases such as argon.
Nesting—The ability of a RIP program to intelligently arrange multiple print jobs efficiently in order to minimize substrate waste when printing. Also the efficient placement of images or jobs in order to minimize waste when cutting.
Network—Connection of computers with cables and software for constant, on-demand communication. With a network, several computers can use or control software installed on a central computer, or server, dedicated to one or a few functions.
Network Manager—In digital signage a device used to control flow of content to screens in various locations.
Newscasting—Sending news out over the Internet, either point-to-point, or with multicast for client computers to receive and display.
Node—Connection point of line segments in an on-screen image. Also called a control point in some sign software.
Nozzle—In inkjet printing, the electromagnetic device contained within a printhead that actually fires the ink droplet. A single printhead may contain 300 to 1000 nozzles. In sandblasting, a nozzle is a device used to direct the grit to the surface to be worked.
Null-Modem—A cable used to connect the serial ports of two computers that are physically close together. The connection simulates a modem connection, but can usually run at a higher baud rate because there is no telephone line noise.
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Off-Gassing—A dye-sublimation term referring to the nature of sublimation inks to gradually vaporize and release gases into the atmosphere. This is a harmless process that occurs primarily when the image is placed under stress of heat and/or pressure such as when packed in a box or exposed to the sun. This is evidenced by the imprinting of one image onto the back of another substrate packed on top of it or by ghosting when a sublimated product is shipped in a plastic bag preventing the expelled sublimation gas from escaping into the air.
Ogee—In computer graphics, a distortion of an image using an S-shaped curve as one baseline, giving an image a wave look.
Ohm—In electrical power, the unit of measurement for resistance in an electrical current; derived from Ohm’s Law, which essentially states that any two of the four basic electrical values can be used to calculate the other two electrical values.
Oligomer—An ingredient in UV-curing inks; a resin with a low molecular weight. The specific oligomers used in free-radical UV-curing inkjet systems have relatively high viscosities, while those in cationic ink systems have a relatively low viscosity.
On-Demand Color—An expression used when referring to any short-run color printing, whether done by inkjet, electrostatic, thermal transfer or direct-to-press process.
Opacity—Measurement of resistance to light passing through a particular substrate.
Opaque—Blocking the passage of radiant energy, especially light. Not allowing light to show through.
Optical Resolution—The maximum physical, or “true”, resolution of a device without the use of software.
Open Channel Letter—A channel letter that has no face and in which the neon tubing is visible.
Ortho—In graphic design, zero degrees horizontal; a command included in several sign-design software packages to set an image to a “perfect” horizontal level.
Out-of-Home Media Network—A form of electronic digital signage similar to a private television channel, run by a company, organization, and/or advertiser. (See also Location-Based Advertising and Location-Based Media.)
Outernet—A term used to describe out-of-home electronic display networks.
Outgas—The characteristic of a solid or liquid to vaporize under heat. Occurs in some plastics and paints if they are not through drying resulting in adhesive failure to anything applied over them. Also describes the release of impurities in vacuum systems such as neon tubes during processing.
Outline/Inline—In computer graphics, a closed-loop path that copies an original’s shape, but is offset by a positive measurement outside the original (outline), or a negative measurement inside the original (inline).
Overlap—Amount of material in a panel (or tile) that duplicates the previous panel, allowing for alignment when assembling and installing a large image. In printing, this refers to where inks lay over one another resulting in bleed.
Overlay—A feature of most video cards that allows particularly smooth digital video playback without overloading the computer’s CPU.
Overprint — The placement of one color over another. In process printing, overprinting can be used to vary tones and shades. With spot color, overprinting is used to create new colors.
Overprint White—Printing application in which white ink is used as a background for reverse-printed transparent stocks, such as back-lit images. White in this application should be somewhat translucent.
Oxygen Inhibition—A limiting factor in free radical UV-curing inkjet systems. The presence of oxygen retards or terminates the curing process. Cationic UV curing inkjet systems are not affected by the presence of oxygen.
Panel—In printing, the division of a job based on the production area of a printing device. If the job size exceeds the production area (width of the printer), it can be divided into panels manually, or using a RIP software program, and then individually printed. Also called tiling.
Parallel Communications—Method of sending information from a computer to another device (such as a plotter or printer) by sending multiple signals at one time through a cable.
Pantone Matching System (PMS)—A numbering system for identifying 3,000+ colors created through combinations of 14 base colors. The Pantone company produces numerous color-matching systems for standard print and computer applications.
Pattern—In sign-making, a full-sized layout of the work to be done.
Pass—In inkjet printing this refers to the number of times a printhead passes over a substrate depositing ink. The greater number of passes, the more ink density is achieved.
PCI (Peripheral Connect Interface)—An advanced expansion-bus standard for internal peripheral electronic digital signage devices, commonly used by high performance graphics adapters.
Pegged Out—Mounting letters so they are separated from the surface on which they’re being attached. Although an important part of affixing reverse channel letters, metal, plastic or wood letters may also be pegged out to keep stains from washing down on the letters or for visual impact.
Perforating Wheel—A toothed wheel on a handle that allows it to rotate freely, used to trace line art, creating perforations for pattern making. Also called a pounce wheel. See also Pounce Pattern and Pounce Pad.
Periodic Scheduling—A type of scheduling that defines ranges of time within which events are allowed to play.
Permit—A license granted by the appropriate authorities to allow a sign to be erected.
PDF (Portable Document Format)—Electronic document format from Adobe Systems Inc. that allows the packaging of files for distribution across platforms for display and printing as originally designed.
Phosphors—Chemical powders used to coat fluorescent tubes. A range of phosphors is available to produce a large variety of colors and whites.
Photo-Cut—Method of vectorizing an image in a parallel-line pattern to give a rough, but recognizable, rendering of sharp outlines from a high- to medium-contrast photograph.
Photoinitiator—A molecular ingredient in UV-curing inks that absorbs incident UV energy, becomes excited and initiates a chain reaction with liquid oligomers and monomers, resulting in polymerization and the creation of a hardened UV ink.
Photostencil—A stencil prepared using photographic, rather than mechanical methods.
Pictogram—A pictorial symbol commonly found in environmental graphics and regulatory (traffic) signs.
Pictorial—A picture on a sign that does not involve animation. Can range from one-color graphic symbols and posterized pictures to full-color scenics and portraits.
Piezo Inkjet - A type of printhead that uses the oscillations of electrically-stimulated piezoelectric crystals to force ink through inkjet nozzles.
Pigment—A compound used to color other materials, such as paints and inks. Pigments are insoluble, finely ground particles and may be organic or inorganic.
Pixel—With digital production, a part of a picture that can be located and placed as an element along the X and Y axes.
Plasma Display Panel (PDP)—A type of flat screen display device that is used for television, computer monitors, and dynamic signage. Similar to an LCD panel, they consist of two layers of glass surrounding cells of xenon and neon glass. Surrounding electrodes switch the cells on and off, causing them to emit light and create the picture. This emitted light makes PDPs have an appealing vibrancy that competes with Cathode Ray Tubes (CRTs), the technology of traditional televisions. Also known as gas plasma displays or plasma displays
Plastic-Faced Letter—Channel letter in which the front of the channel is covered by plastic material or facing, hiding the neon tube from view.
Plot Plan—A drawing or sketch showing the layout looking down on the site on which a sign is to be erected.
Plotter—Device that interprets information sent from a computer and moves a tool head to a series of coordinates based on the device’s X and Y axes. Sign makers use a plotter equipped with a knife to cut vinyl, with the X and Y coordinates forming an outline that can be weeded and installed on a surface.
Plug-Ins—Small, limited-purpose programs that work with and add capabilities to larger graphics applications such as Photoshop.
PMT (Photomultipliers Tubes)—Light-sensitive elements used in drum scanners. PMTs accept four beams of light from a scanner—RGB and a separate beam for image sharpness—for eventual converting to digital information. Usually seen as more-sensitive and having greater dynamic range than CCD-based scanners.
Polariscope—An instrument for ascertaining, measuring, or exhibiting the properties of polarized light; can be used to check neon tubes for stress.
Pole Sign—A free-standing sign, usually double-faced, mounted on a round pole, square tube or other fabricated member without any type of secondary support.
Polling—Method where a computer sends a signal to a plotter or printer requesting information on the current production area. The device sends back production parameters; the production software then sets panels based on the information. Works only with serial communications.
Polling Interval—The length of time that may elapse before a media player checks for a certain condition, such as whether a job has been delivered to its job folder, or whether its script has been updated.
Polycarbonate—A type of plastic used in sign faces, noted for its heat-resistance and impact strength.
Polymer—A stable chemical compound or mixture of compounds consisting essentially of repeated structural units. Monomer-based UV-curing inks, once cured, become a solid polymer.
Polymerization—The process of combining unstable molecules to form solid polymer structures. Specifically in UV-curing, polymerization describes the chain growth of monomers and/or oligomers that have been triggered by a photoinitiator and/or sensitizer in the ink.
Polypropylene—A type of plastic used in banners, noted for its flexibility at low temperatures and its resistance to chemicals. Noted for is recyclability.
Polyurethane—Any of various synthetic polymers used in elastic fibers, molded products, coatings, etc.
Porcelain Sign—A traditional type of metal sign utilizing porcelain enamel paints topped by a ceramic slip to create a durable, glass-like surface that’s impervious to the environment.
Portable Sign—A freestanding, on-premise sign that is not designed to be permanently affixed to a base.
Positive Space—In design, the copy and art seen on a sign face. The opposite of negative space.
Poster—A series of paper sheets printed for use on a billboard. Also, a type of sign, typically printed on paper, and intended for indoor use.
Posterization—Process of changing the number of colors in an image, usually to a lesser total. Can sometimes aid in speeding the RIP process by providing less information for rasterization, but can affect specific color integrity.
PostScript—Graphics language that creates vector-based images that, by computer code, allows for proportional scaling. It’s what makes most scalable type and artwork possible for most Windows- and Macintosh-based graphics software.
Pounce Pad—A small fabric pouch filled with white chalk powder that, once a paper with perforations outlining a design is laid over the substrate, can be patted over, leaving behind powder marks of the design to be painted.
Pounce Pattern—A full-sized pattern of any design to be painted. Once the pattern is created, the outline is perforated using a manual or electric tool. The pattern is then held firmly against the substrate and the perforations patted with powder using a pounce pad, leaving an outline of the design.
PPI (Pixels Per Inch)—In digital printing, describes how many of the pixels in a raster image will occur in one inch. The higher the number of pixels-per-inch, the greater the resolution and the less distinguishable each becomes.
PPI (Pulses Per Inch)—In laser engraving, the number of times a laser beam fires per inch of horizontal travel.
Preflighting—Checking a graphic file for potential problems before sending it for final output, essentially to find font, color and other problems. Usually done with software.
Pressure Sensitive Adhesive (PSA)—An adhesive that activates its adhesive properties only when pressure is applied to the surfaces it is to be adhered to. Sometimes used to refer to vinyl with a pressure sensitive adhesive backing such as in PSA vinyl.
Primary Colors—Color that cannot be created by mixing other colors within the gamut of a given color space, but mix to create all other color combinations within that space. Red, green and blue (RGB) are additive primaries of emitted light, while cyan, magenta and yellow (CMY) are subtractive primaries of reflected light. Black (K) is added to CMY to produce denser, truer black images.
Prime—To coat a raw substrate prior to the application of paint or adhesive. A primer coat prevents subsequent coats of paint or adhesive from being absorbed.
Print Driver—Computer software that allows the computer to communicate with and control the actions of a printer or other output device.
Printhead—The device in an inkjet printer that shoots droplets of ink onto the substrate. Printheads contain nozzles (grouped by color), and typically shuttle back and forth across the substrate as ink droplets are forced out of the nozzles. Most printheads are either thermal or piezo (piezoelectric).
Process Color—The three primary colors of printing—cyan (blue); magenta (red); and yellow; plus black. When printed as halftones in that order, they create a full range of natural colors. Their printing is also known as four-color process or CMYK.
Production Area—Space on a router or engraving table where the tool can touch the substrate and cut. Some tables may have non-production areas (or margins) for setting of clamps, etc.
Profile—In color management, a data file that describes various characteristics and attributes of a computer monitor, printer ink and/or media, which when used in combination, yield predictable color results. Standards for the creation of profiles were established by the ICC.
Projecting Sign—A sign that is attached to a building but extends beyond the building structure.
PSA Vinyl—A type of vinylfilm that has an pressure sensitive adhesive backing that adheres to a surface only when pressure is applied.
Public IP Multicast Displays—A device capable of receiving an IP multicast transmission and displaying the contents, often used to update large numbers of visual display devices including digital signage.
Pumping System—In neon tube production, the pumping system is used to remove impurities from the tubes and fill them with rare gases. A pumping system typically consists of a manifold, vacuum pumps, rare gases, a bombarder and electrical controllers.
Push Software—Software that pushes news and information from a broadcast server to a media player client. Push technology can be used to deliver vital information to screens without the player asking.
Push-Through—A letter or graphic which is cut out, then pushed through a corresponding space that has been removed from the sign substrate.
PVC (Polyvinyl Chloride)—The most common form of plastic in use today. PVC is extruded or cast as sheets, tubing or films. PVC films are commonly referred to as vinyl.
Pylon—Any free-standing sign that is not a pole or ground sign.
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Queue—An electronic holding area, usually in random-access memory (RAM) or on a hard drive, where data waits before being sent to a printer for output. Synonymous with spooler.
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Raceway—A metal structure enclosing the electric components of a sign.
RAM (Random Access Memory)—The high-speed portion of a computer’s data storage that is held on special chips for use in current applications or procedures. RAM is said to be volatile if the stored information is lost when power is disrupted.
Raster Image—An image created by a collection of pixels arranged in a rectangular way.
Rasterization—The process of translating data into a bitmap pattern for output by a digital printing device.
Readability—The quality of a sign’s overall design that allows the viewer to correctly interpret the information presented on it, and the optimum time and distance in which this can be done. Letter size and style, color contrast between the letters and background, and a sign’s layout all contribute to readability.
Reclaiming—In screen printing, the removal of a stencil from the screen mesh so it can be used again.
Reflective—The ability of a surface to return some or all of the wavelengths of light that strike it.
Reflective Sheeting—Film with very small glass or glass-like materials encapsulated below its surface, creating the ability to bounce light beams back to its source.
Registration—In screen printing, the correct placement of the image to be printed on the substrate. In multi-color printing, registration also refers to the correct alignment of the colors with one another.
Regulatory Signs—Signs installed by various government bodies to acquaint the public with traffic laws and other regulations.
Relief—The projection of art from a flat surface.
Remote Control—A method for changing the messages on electronic changeable copy signs where the data is provided to the control console by telephone.
Resampling—Changing the resolution of a bitmap image file without altering the image’s physical size.
Resin Transfer—Method of heating a color on a carrier sheet (called a ribbon or foil) and printing it onto a substrate. The plastic-based resin is fused onto a material such as vinyl, creating a more-permanent image with waterfastness and UV protection.
Resistance—A property of most conductors (wires) that restricts the flow of an electrical current.
Resistor—The electronic equivalent of a fixed valve–available in a wide range of values.
Resize—To change the reproduction size of an image so prints can be made smaller or larger. Significant up-sizing often results in jaggies.
Resolution—The degree of crispness/clarity of an image. In digital imaging, resolution is measured by the number of pixels (or dots) of color information per horizontal inch of an image; the higher the number (measured horizontally and vertically) the more precise the pictured image. In plotting, resolution is the degree of accuracy that a plotter will place a knife-head in relation to a theoretical, perfect location of a coordinate.
Retarder—An additive that slows the drying time of ink or paint.
Reverse Channel Letter—A channel letter that has a face and sides but no back. It is pegged out from a background surface. When the inside of the channel is lit, it produced a halo effect around the letter.
Revolving Sign—A sign which has the ability to turn 360 degrees because of the presence of an electric motor to drive its moveable parts. All or a portion of the sign may revolve at a steady or variable speed depending on the sign.
RGB (Red, Green, Blue)—The three primary additive colors used by monitors and scanners for transferring and representing color data. In digital imaging most input and display are seen in RGB, while printed output is created using subtractive CMYK colors.
RGB Display—Any high-quality electronic screen display that makes use of primary RGB colors to produce a full-color display. For example, some electronic message centers achieve full color by utilizing red, green and blue LEDs.
RIP (Raster Image Processor)—Software used to create and place dots (or bitmaps) for printing, and then transferring that information to a printer.
RSS—In electronic digital signage, RSS (most commonly translated as “Really Simple Syndication”), is a family of Web feed formats used to publish frequently updated works such news headlines, stock updates, weather reports and the like. An RSS document (called an “RSS feed”, “Web feed”, or “channel feed”) includes full or summarized text, plus metadata such as publishing dates and authorship.
Router—In sign-making a router is a machine tool that mills out the surface of metal or wood, usually equipped with various bits and able to remove material along the X,Y and Z axis. In digital signage a router is a networking device whose software and hardware are usually tailored to the tasks of routing and forwarding information. For example, on the Internet, information is directed to various paths by routers.
Routing—The elimination of material in a substrate, using a router to remove material.
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Samples Per Inch—Unit of measure used to describe the input resolution of a device, such as a scanner or camera, in one-linear-inch increments. Each data point in an RGB image capture includes separate red, green and blue calculations.
Sampling—Selection by a computer of the best pieces of information; in scanning, the best bits to interpret the scanned image and present the best-possible image for editing and printing.
Sandblasting—A pressurized stream of sand or synthetic particles used to remove material from a substrate, such as glass, wood or HDU. A rubberized stencil of the artwork is either hand- or computer-cut and applied to the substrate, which is then sandblasted.
Sans Serif—Any font or typeface that lacks serifs. See also Serif.
Scanner—Device employing a mechanism such as a CCD array, to scan an image, printed text or artwork and converts it to a digital image. A common example is the desktop (or flatbed) scanner where the document is placed on a glass window for scanning. See also Drum Scanner and Linear Scanner.
SCGFP (Secondary-Circuit Ground-Fault Protection)—A ground fault detection system built into neon transformers based on the UL 2161 Standard, that detects current flow to ground and, if it reaches a preset level (15 mA or greater), turns off the transformer.
Scoring—To cut or notch a material prior to bending it. Sufficient scoring of some substrates—glass and some thicknesses of PVC boards, for example—will also allow them to be broken cleanly without cutting them all the way through.
Screen Angles — In halftone printing, the geometric intervals used to place the four screens in order to eliminate moiré patterns within a print.
Screening—Method for positioning dots for reproduction of an image by a printer. The two basic methods are halftone, where dots of varying sizes are placed in an exact, evenly spaced order; and stochastic screening, where small dots of the same size are placed in a random-looking, variable-spaced distribution on an image. Halftone is also known as amplitude modulation (AM), and stochastic as frequency modulated (FM).
Screen Printing—Historically one of the oldest and simplest forms of printing. A print is made by using a squeegee to force ink through a stencil or emulsion that’s supported by fabric stretched over a frame. Although also referred to as silk screening, several synthetic fabrics have replaced silk as the fabric of choice.
Seam—A line formed by the joining together of two separate materials by their edges, as with flexible face material or wood, metal or plastic sheets.
Second-Surface—Refers to a sign made of a clear substrate, such as glass or acrylic, where the art is done in reverse on what will be an interior face of the sign, providing extra protection.
Self-Running Script—A script designed to run continuously; for example, to demonstrate a product or service, or provide information without interruption. Also continuous script.
Sequence—The operation of a flasher or chaser, or to the order and frequency of messages in an electronic changeable copy sign, or the pattern of an advertiser’s billboard campaign. Also, the order in which inks are deposited by a printing device.
Sequencer—A hardware device or computer software that is used to compose a musical score, transcribe it into a MIDI file and play or record the result using MIDI instruments. Often used to create audio portions of digital signage content.
Serial Communications—Method of sending information from a computer to another device (such as a plotter or printer) by sending one signal at a time through a cable.
Serif—A small line or embellishment finishing off the strokes of letters in some fonts. Well-known serif fonts include Souvenir, Times Roman and Garamond.
Server—Computers used for limited tasks. In networks, servers may act as a hub for storing programs used by different workstation computers; can also act as the machine solely for RIP purposes in large-format color printing.
Service Cover—In an electric sign cabinet a panel that allows ready access to the bulbs or lamps and the electrical connections for their replacement and maintenance.
Setback—The distance between the primary face of a sign and the property line.
Shadow—Duplication of an image that’s slightly offset. Drop shadow is a simple copy and offset; block shadow joins the outlines of the original and duplicate to create a 3D-relief effect; and cast alters the shape and size of the duplicate to imitate shadows cast from varied placement of light.
Shadow Point—The darkest tone in an image that is printable. Tones darker than the shadow point print as black. The opposite of white point.
Sharpen—A process in image-editing software to improve the contrast of tones within an image. This can be a universal (all tone) operation or target specific areas.
Sheet Metal—Aluminum or steel in sheets or plates used as a sign substrate.
Showcard—An interior sign utilizing a card stock substrate and often decorated with tempera paints. The standard showcard size is 28" x 44".
Signing Schedule—Lists of all the signs to be installed, the locations where they are supposed to be placed and the information they should contain. Supplied by the architect, designer or contractor on major projects.
Silhouette—The overall shape of a sign, or a block of copy within a sign.
Simulations—Since spot-color inks are made from unique pigments or dyes, many are outside the color gamut of four-color process printing. Out-of-gamut colors cannot be matched exactly on the press or printer. Spot colors can also be converted from their own individual inks to process colors, which are known as simulations.
Single-Face—A sign consisting of one face, rather than back-to-back faces.
Single-Pass Printing—Inkjet printing process that uses arrays of stationary printhead clusters (also called “color bars”) instead of a shuttling printhead. A substrate passes beneath printhead arrays in a single pass. Not yet commonly applied to wide format printing.
Sizing—The substance applied to the substrate before gilding in order to make the gold leaf adhere to the surface.
Skeleton—The metal frame on which a sign is installed.
Slice—Cutting of an image by means of using parallel lines to eliminate the image after alternating lines. Also called striping in some sign softwares.
Smoothing—Method used to vary speed and movement of material and knife-head of a plotter, making for less-jagged transitions between nodes during cutting.
Snipe Sign—A sign added to a structure where it is neither the main nor permitted sign.
Soda-Lime Glass—The most common glass manufactured and the type used in most fluorescent tubes and incandescent bulbs. Soda-lime glass is made from a combination of sand, limestone and sodium carbonate. Soda-lime glass can be either colored glass or clear glass.
Soil Bearing—Refers to the ability of un-compacted soil to support a weight, such as the footing for a sign. The measurable figure usually has to be obtained from an engineer, and is expressed as pounds per square foot.
Solvent—A petroleum-based liquid used to modify oil-based paints and inks and to remove them from frames and brushes.
Spacer—Any device used in mounting letters or signs which separates them from the surface to which they are being installed.
Special Event—In electronic digital signage content, an event that is not associated with a file. Special events can be added like pages in the main menu, or like elements in the list menu. They are used to control a device or an element, for example, changing the volume of a sound.
Spectacular—An extra-large outdoor sign that incorporates special lighting and/or motion effects, or an interior sales display that also includes special lighting and motion elements.
Spectrophotometer—A color measurement device using the distinct wavelength (spectral) values of light to indicate a spectral reflectance, emittance or transmittance curve along the visible spectrum (380–720 nm). A more sophisticated device than a Colorimeter.
Speedball Pen—A type of hand-lettering pen preferred by many sign artists for use on showcards because of its rounded point, and because the pen’s ink container opens, making it easy to clean.
Spindle—Device that holds the cutting bit during the routing or engraving process.
Spooler—Area where data used in printing is held before going to the printing device. It may be part of the computer’s RAM, or its hard drive.
Spot Color—Color used for a specific need within a print. It may be a separate, special tone to match a corporate color, or it may result from the overlapping of colors within a halftone.
Spot White—An application in which white ink is used as an independent color (usually for printing text on a non-white surface).
Sprocket Feed—Process where material is fed through a plotter by aligning pre-punched holes along the medium edges with raised points along the ends of the plotter’s motor-driven drum wheel. Also called tractor feed or pin feed.
Sputtering—Occurs when the electrode in a neon tube, because of the heat and electrical forces, gradually erodes, blackening the ends of the tube near the electrode and decreasing gas pressure, eventually making the tube inoperative.
squeegee—In screen printing, a flexible blade mounted in a wood or metal handle and used to force ink through a stencil mounted on a screen. In sign making, a hard plastic or nylon blade used to apply pressure to increase surface adhesion between cut vinyland the transfer tape or between the vinyl and sign face.
Stencil—A thin sheet of material into which a design is cut; often used in various screen printing processes.
Stepper Motor—A type of motor used on computerized routers and engravers to accurately move a cutting tool or lens in either the X or Y axis.
Stippling—A method for taking out brush marks and creating a transparent look on windows.
Stochastic Screening—Process that creates colors within a print by varying the number and location of its dots, rather than through varying the size of the dots.
Stopcock—A valve for controlling or stopping the movement of a liquid or gas.
Store and Forward—A networking term referring to when information is stored at routing points before its ultimate destination. Store and forward can be used to reduce the load on the original server. Media players can retrieve their data from other players instead of the original broadcast site.
Streamer—A long, narrow banner intended for interior or window display only.
Stretching—The process of securing mesh to a frame in screen printing.
Structure—In the sign industry, a structure designed for and capable of supporting a sign.
Subtractive Colors—The color system used in printing in which Cyan, Magenta and Yellow (CMY) colors are used to create all other colors in color printing. When CMY are combined at 100 percent on a white surface, black is produced. Most printing systems also use black(K) pigment rather than always combining CMY.
Substrate—The material out of which a sign face is made. Wood, metal sheeting, paper and acrylic are all sign substrates. In screen printing and inkjet printing, a substrate can be any printable material, but usually some form of rigid sheet; or it may refer to a rigid mounting board.
Supports—Insulators that support a neon tube, as well as hold it away from the background surface and provide some impact resistance. Also known as stand-offs.
SWOP (Specifications for Web Offset Publications)—Refers to, among other things, inks formulated exclusively for web offset printing, and provides the basis for standard Pantone color matching.
Symmetry—The balance of design elements in which one side equals the other.
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T-Slot—Channels in a router or engraving-table surface that hold special clamps for holding-down substrates. The T-clamp goes into a slot like an upside-down “T”.
Tack—The stickiness of an adhesive under a given condition. Some adhesives require a particular temperature range for maximum tack.
Tactile Sign—A sign—or area within a larger sign—that conveys its message through raised or engraved art, making it accessible to the visually impaired. Term could be applied to Braille signage.
Tangential Knife—Blade holder on a plotter that is mechanically turned (usually with a motor/belt drive) to aid in deflecting the edge to create curved cuts.
Tempera—Pigment mixed in a water medium, usually with a binder and adhesive. Tempera paints produce a luminous effect, often used on showcards.
Template—A pattern, often made of thin metal or wood.
Temporary Sign—Any sign which is not intended to be permanently installed, such as banners and construction site signs. Often, sign codes seek to limit the length of time a temporary sign can be in place.
Termination—In UV-curing, the cessation of the process of crosslinking due to oxygen inhibition (in free radical UV curing systems), or relative humidity inhibition (in cationic UV curing systems).
Thermal Inkjet—Inkjet printhead technology where inks are heated in a chamber located above the printhead to a temperature greater than the boiling point of the liquid. Heat changes the characteristics of the fluid, causing it to expand and be expelled through the printhead nozzle onto the substrate.
Thermal Transfer Printer—Printing device that uses a heating-element head to transfer resin- or wax-based colors from a carrier sheet (a ribbon or foil) to a medium.
Thermoforming—Taking a flat sheet of material and giving it dimension by heating and then forcing it into a mold either mechanically or pneumatically. Also know as pan-forming.
Thinner—Any liquid used to reduce the thickness of paint or ink.
Three-D Engraving—Routing procedure where the tool bit can be moved independently along the up-and-down Z axis while still traveling an X/Y axes tool path.
Through-Cure—In UV-cure printing, when the level of polymerization is equal at virtually all depths of the ink film (versus surface cure, which occurs when only a film of the ink has been completely cured). Both cationic and free radical UV-curing systems require good through cure.
Throughput—Actual speed of a printer or plotter in completing a job. Difficult to measure, but it represents the unit’s ability to process information and print and/or cut an image.
Thumbnail—A type of rough sketch before preparing a complete design. In digital imaging, a very small version of a larger file used for quick visual identification.
Time Switch—A switch which utilizes a clock or timer to automatically turn on and off electric signs at set times.
Time and Temperature Display—Among the first electronic devices to change copy, these popular signs alternate between showing the time and temperature. Some also display simple messages.
Timeout—A time limit for an operation. If the timeout period expires before the operation completes successfully, some default or alternative action is taken.
Titanium Dioxide—Pigment used to make white inks (both UV-curing and eco-solvent). TiO² is dense and heavy and has only recently been used in digital printing applications.
Tolerance—The amount of acceptable difference between a known standard and a measured sample.
Tone—The effect on a color brought about by blending it with another color.
Tool In/Out—Command given by computer to router to place a bit into material to begin routing. Controlling the speed and angle of tool in/out makes for more-accurate routing and less chance of damaging the material.
Topology—Physical and logical arrangement of a networked system.
Touch Screen—Also called a touch-sensitive screen; a computer monitor attachment that can sense the location at which a viewer touches the screen to respond to a question or prompt in a script. Often used as part of an interactive kiosk.
Traffic Count—The estimated number of people who will see a sign in a given time period.
Transfer Paper—A special paper used for the transferring of color images to substrates by using a heat press or similar device.
Transfer Tape—Medium-tack adhesive-coated translucent paper, placed on weeded vinyl images still on the original carrier liner; the tack of the tape is stronger than the adhesion of the vinyl to the coated liner, so the image is pulled off the liner in a transfer to another surface.
Transformer—In neon displays, the mechanical or electronic component that transforms incoming voltage (primary voltage) into a higher voltage (secondary voltage). Also an electrical component with two or more sets of wire windings separated by some insulation material. The windings are wound on a magnetic core to magnetically couple energy between the winding. Transformers only work with a changing voltage. They act as a virtual electrical short if you apply Direct Current (DC) to them. They may be designed to work on line frequency AC (50Hz or 60Hz) or high frequency (greater than 20KHz) in a Switch-Mode power supply. They provide voltage scaling and galvanic isolation.
Transistor—The electronic equivalent of an adjustable valve.
Trapping—In screen printing, to overlap one color on another. Trapping may result in the creation of a third color in the overlap area. See also Bleed.
Triple Message Sign—A type of sign consisting of rotating triangular louvers. The louvers turn in unison, showing three different messages as the three faces as exposed.
Tube Colors—Tubing for neon signs is produced as a clear glass, or in colors. Different tube colors serve as filters that only allow the desired to color to shine through. In many cases the only way to achieve rich primary colors is through colored glass.
Tube Diameter—The term often used to describe the width of a tube, expressed in millimeters.
Typeface—The design of a given set of letters, numbers and symbols, without reference to size or width. See also Font.
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UCR (Under Color Removal)—Color separation process in which black ink is used to replace cyan, magenta, and yellow (CMY) in shadow areas where the three inks overlap, since black (K) is the combination of CMY. (Similar to GCR.)
UL (Underwriters Laboratory)—Private organization which tests electrical devices and their construction and certifies their safety.
UV (Ultraviolet) Light—Part of the spectrum ranging from 185 to 450 nanometers. UV has both a negative and positive influence on the sign industry. When UV strikes certain surfaces, such as the phosphors in neon and fluorescent tubes, it is transformed into visible light. UV is also used for curing some screen printing inks. UV is also the prime cause of pigment failure in some paints and vinyl, especially red.
UV-Curing—In certain inkjet printers, the process in which a lamp emitting ultraviolet (UV) light is used to transform monomer-based liquid inks (deposited onto a substrate via the printhead) into polymer-based solid inks. Commonly used process in many digital flatbed printers. The ink chemistry employed can be either free radical UV curing (common) or cationic UV curing (not yet widely used).
Underbase White—Printing application in which a solid field of white ink that is laid down to be overprinted with an image, as when printing onto a non-white surface.
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Vacuum Forming—Taking a flat sheet of plastic material and giving it dimension by placing it in a mold, heating it until it’s flexible and then withdrawing the air in the mold, creating a vacuum. See also Thermoforming.
Vacuum Gauge—Measures the degree of vacuum in a neon manifold by measuring residual gas pressure.
Vacuum Table—Surface where hold-down of a substrate for printing, routing or engraving is done by air suction, as opposed to clamping or using a T-slot table. Suction is usually provided by a vacuum pump.
Value—When dealing with color, value is the measurement of brightness, with zero percent representing solid black.
Value Engineering—Assessing a sign based on the cost of its materials, design, installation and maintenance, with the goal of getting the best value for the money.
Vanishing Point—In graphic design, the place where a series of angled lines continue but are too small to be detected by the unaided eye. The lines converge into one point and seem to disappear, creating a 3D relief effect.
Variable Droplet Technology—Printhead design where individual nozzles use multiple micro-pulses to create different sized ink droplets from the same aperture. For example, a nozzle with a native drop size of 12 pl can also produce drops of 24, 36, 48 or 60 pl depending on the number of micro-pulses used. Printheads using this technology can achieve high resolution images at higher speeds.
Variance—A method where a government body deviates from the terms of its sign or zoning code. Typically, obtaining a variance for a sign requires the applicant to show that it would not be contrary to the public interest or where—owing to conditions peculiar to the property—a literal enforcement of the regulations would result in unnecessary and undue hardship.
Vector—In cut-vinyl sign making, a line segment between two coordinates, on which a knife or tool path can be created for plotting or routing. Also, a line that has a specific direction and length that’s proportional to some representative unit value.
Vector Image—A computer image that defines graphic pixels through the use of mathematical descriptions of paths and files.
Vectorization—Function of tracing around a bitmap image to create an outline comprised of line segments, or vectors. Also called auto-tracing.
Versionation—the process of inserting a serial number into a file name or folder name to indicate the order in which successively newer versions of a file with the same base name have been received on the media player.
Viscosity—The thickness of a paint or ink. Specifically, the resistance of adjacent levels of a fluid ink to flow under pressure and or shearing forces. High viscosity represents high resistance (thick, heavy ink); low viscosity represents low resistance (thinner, free-flowing ink)
VOCs (Volatile Organic Compounds)—Petroleum-based chemical compounds with high vapor pressure and low water solubility (evaporate easily). Commonly found in industrial solvents, including those used as carriers in solvent-based inks. VOCs are considered toxic, and airborne VOCs are federally regulated in some industries.
Volt/Voltage—A unit used to measure electrical potential (force or pressure).
VRAM (Video Random Access Memory)—Storage chips in a computer that are devoted exclusively to the display of images on a monitor screen. Increased VRAM allows displays to redraw or refresh an image at a higher speed.
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Walldog—Slang term for old-style sign painters who produce signs, murals and other large graphics by hand, by painting directly onto a blank exterior wall section. See also Letterheads.
Wall Mount—A single-face sign mounted on a wall. Another name for a wall sign.
Washout—The process of opening up the image areas of a screen after a photostencil has been exposed.
Waste Heat—Electrical energy that is converted to heat as part of the power conversion and regulation process that must be dissipated.
Water Jet Cutter—A tool that utilizes a high velocity and high pressure jet of water, sometimes in combination with an abrasive, to make close-tolerance cuts in various hard materials such as stainless steel.
Wayfinding—A system of signage and graphics which is designed to give direction to a given destination. While the copy and graphics on a building’s signs are important to the process, wayfinding also depends on the information inherent in a building’s design.
Weed—In cut-vinyl sign making, the process of peeling extraneous vinyl (or matrix) away from a plotter cut, leaving only the sections representing the final image. Pulling the extra vinyl away in one quick stroke is known as rip-weeding.
Weld—Combination and merging of two outlines to create one image. Depending on the software, the final outline may be altered in a variety of ways.
White Point - The lightest tone in an image that is printable. Tones lighter than the white point print as white. The opposite of shadow point.
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X Axis—Theoretical horizontal line providing a lengthwise reference point for plotters and routers.
X Height—In typography, a given typeface, the height of the lowercase letters that do not have an ascender or a descender.
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Y Axis—Theoretical vertical line providing a longitudinal reference point for plotters and routers.
YCC—Color space developed by Eastman Kodak that defines colors by luminance (Y) and two levels of chrominance (C and C).
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Z Axis—Theoretical line providing a depth reference point for routers.
Zip/Zip File—To reduce file size by using file compression algorithm programs such as PKZIP, WinZIP or StuffIt; a zip file is any file compressed using zip software.
Zoom—Making an image or image part become larger (zooming in) or smaller (zooming out) as it appears on the monitor. A lens that changes magnification.