A fourteen-segment display (FSD) (sometimes referred to as a starburst display or Union Jack display) is a type of display based on 14 segments that can be turned on or off to produce letters and numerals. It is an expansion of the more common

seven-segment display A seven-segment display is a display device for Arabic numerals, less complex than a device that can show more characters such as dot matrix displays. Seven-segment displays are widely used in digital clocks, electronic meters, basic calculators, ...

, having an additional four diagonal and two vertical segments with the middle horizontal segment broken in half. A seven-segment display suffices for numerals and certain letters, but unambiguously rendering the

ISO basic Latin alphabet The ISO basic Latin alphabet is an international standard (beginning with ISO/IEC 646) for a Latin-script alphabet that consists of two sets (uppercase and lowercase) of 26 letters, codified in various national and international standards and u ...

requires more detail. A slight variation is the sixteen-segment display which allows additional legibility in displaying letters or other symbols. A

decimal point FIle:Decimal separators.svg, alt=Four types of separating decimals: a) 1,234.56. b) 1.234,56. c) 1'234,56. d) ١٬٢٣٤٫٥٦., Both a comma and a full stop (or period) are generally accepted decimal separators for international use. The apost ...

comma The comma is a punctuation mark that appears in several variants in different languages. Some typefaces render it as a small line, slightly curved or straight, but inclined from the vertical; others give it the appearance of a miniature fille ...

may be present as an additional segment, or pair of segments; the comma (used for triple-digit groupings or as a

decimal separator FIle:Decimal separators.svg, alt=Four types of separating decimals: a) 1,234.56. b) 1.234,56. c) 1'234,56. d) ١٬٢٣٤٫٥٦., Both a comma and a full stop (or period) are generally accepted decimal separators for international use. The apost ...

in many regions) is commonly formed by combining the decimal point with a closely 'attached' leftwards-descending arc-shaped segment. Electronic alphanumeric displays may use

LED A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresp ...

LCD A liquid-crystal display (LCD) is a flat-panel display or other electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers to display information. Liquid crystals do not em ...

s, or

vacuum fluorescent display A vacuum fluorescent display (VFD) is a display device once commonly used on consumer electronics equipment such as video cassette recorders, car audio, car radios, and microwave ovens. A VFD operates on the principle of cathodoluminescence, ...

devices. The LED variant is typically manufactured in single or dual character packages, allowing the system designer to choose the number of characters suiting the application. Often a character generator is used to translate 7-bit ASCII character codes to the 14 bits that indicate which of the 14 segments to turn on or off.

Character encoding

By lighting different elements, different characters can be displayed. In a 14-segment display, there is also an optional 15th segment which is a decimal point (denoted as "DP").

Decimal

Latin alphabet

A 14-segment display is mostly used to display text because the 14 elements allow all Latin letters to be displayed both in

upper case Letter case is the distinction between the letters that are in larger uppercase or capitals (more formally ''#Majuscule, majuscule'') and smaller lowercase (more formally ''#Minuscule, minuscule'') in the written representation of certain langua ...

and

lower case Letter case is the distinction between the letters that are in larger uppercase or capitals (more formally ''majuscule'') and smaller lowercase (more formally '' minuscule'') in the written representation of certain languages. The writing system ...

(with a few exceptions like "s").

Applications

Multiple-segment display devices use fewer elements than a full dot-matrix display, and may produce a better character appearance where the segments are shaped appropriately. This can reduce power consumption and the number of driver components. Fourteen-segment gas-plasma displays were used in pinball machines from 1986 through 1991 with an additional

and period part making for a total of 16 segments. Fourteen and sixteen-segment displays were used to produce

alphanumeric Alphanumericals or alphanumeric characters are any collection of number characters and letters in a certain language. Sometimes such characters may be mistaken one for the other. Merriam-Webster suggests that the term "alphanumeric" may often ...

characters on

calculator An electronic calculator is typically a portable electronic device used to perform calculations, ranging from basic arithmetic to complex mathematics. The first solid-state electronic calculator was created in the early 1960s. Pocket-si ...

s and other

embedded system An embedded system is a specialized computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is e ...

s. Applications today include displays fitted to telephone

Caller ID Caller identification (Caller ID) is a telephone service, available in analog and digital telephone systems, including voice over IP (VoIP), that transmits a caller's telephone number to the called party's telephone equipment when the call is ...

units, gymnasium equipment, VCRs,

car stereo Vehicle audio is equipment installed in a car or other vehicle to provide in-car entertainment and information for the occupants. Such systems are popularly known as car stereos. Until the 1950s, it consisted of a simple AM radio. Additions sin ...

microwave oven A microwave oven, or simply microwave, is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range. This induces Dipole#Molecular dipoles, polar molecules in the food to rotate and ...

slot machine A slot machine, fruit machine (British English), poker machine or pokie (Australian English and New Zealand English) is a gambling machine that creates a game of chance for its customers. A slot machine's standard layout features a screen disp ...

s, and DVD players. Such displays were very common on pinball machines for displaying the score and other information, before the widespread use of dot-matrix display panels.

Incandescent lamp

Multiple segment alphanumeric displays are nearly as old as the use of electricity. A 1908 textbook describes an alphanumeric display system using incandescent lamps and a mechanical switching arrangement. Each of 21 lamps was connected to a switch operated by a set of slotted bars, installed in a rotating drum. This ''commutator'' assembly could be arranged so that as the drum was rotated, different sets of switches were closed and different letters and figures could be displayed. The scheme would have been used for "talking" signs to spell out messages, but a complete set of commutator switches, drums and lamps would have been required for each letter of a message, making the resulting sign quite expensive.

Cold-cathode neon

A few different versions of the fourteen segment display exist as cold-cathode neon lamps. For example, one type made by Burroughs Corporation was called "Panaplex". Instead of using a filament as the incandescent versions do, these use a cathode charged to a 180 V potential which causes the electrified segment to glow a bright orange color. They operated similarly to

Nixie tube A Nixie tube ( ), or cold cathode display, is an electronics, electronic device used for display device, displaying numerals or other information using glow discharge. The glass tube contains a wire-mesh anode and multiple cathodes, shaped like ...

s but instead of the full-formed numeric shapes, used segments to make up numerals and letters.http://www.ineedcaffeine.com/content/the-burroughs-b7971/ Burroughs B7971 segmented display tube illustration, retrieved 2012 July 19

Examples

File:14segment LED Display.jpg, A four-character 14-segment clock display. Note unbroken top and bottom segments in comparison with a sixteen-segment display. File:LCD Display of HP41CX (cropped).jpg, Fourteen-segment characters on Hewlett-Packard's HP-41 range of programmable engineering calculators from the late 1970s. File:14 segment LCD on HP 3478A 20130221.jpg, 14-segment characters on the Hewlett-Packard HP3478A multimeter. File:Car stereo display.jpg, Fourteen-segment characters on an after-market car stereo LCD. File:Sony MHC-EC55.jpg, alt=A Sony Mini Hi-Fi Component System which utilizes a fourteen-segment display., An inverted, backlit fourteen-segment LCD display used in a Sony MHC-EC55 mini Hi-Fi component system.

References

External links

{{DEFAULTSORT:Fourteen-Segment Display Display technology