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Fourteen-segment display

{{Short description|Display made up of 14 segments used for displaying numbers and Latin letters}}

{{more citations needed|date=August 2012}}

File:14-segment.svg

A fourteen-segment display (FSD) (sometimes referred to as a starburst display or Union Jack display{{cite web|title=AlphaNum G click with 14-segment LED display released|url=https://www.mikroe.com/blog/alphanum-g-click-with-14-segment-led-display-released|website=MikroElectronika Blog|publisher=MikroElektronika|access-date=11 March 2018}}{{cite web|title=EFM32 Series 0 LCD Driver Application Note|url=https://www.silabs.com/documents/public/application-notes/an0057.0-efm32-segment-lcd.pdf|publisher=Silicon Laboratories|access-date=11 March 2018|page=11}}) 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, 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 requires more detail.Richard C. Dorf (ed.) The Electrical Engineering Handbook, CRC Press, Boca Raton, 1993, {{ISBN|0-8493-0185-8}} page 1770 A slight variation is the sixteen-segment display which allows additional legibility in displaying letters or other symbols.

A decimal point or comma may be present as an additional segment, or pair of segments; the comma (used for triple-digit groupings or as a decimal separator 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 LEDs, LCDs, or vacuum fluorescent display 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.

Maxim Integrated.

[http://www.maximintegrated.com/app-notes/index.mvp/id/3211 "Application Note 3211: Driving 14-Segment Displays"].

2004.

Character encoding

File:Arabic number on a 14 segment display.gif

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 =

class="wikitable"

|+Hexadecimal encoding of decimal numbers for 14-segment display

!Digit

!0

!1

!2

!3

!4

!5

!6

!7

!8

!9

Hex code

|0xC3F

|0x406

|0xDB

|0x8F

|0xE6

|0xED

|0xFD

|0x1401

|0xFF

|0xE7

= Latin alphabet =

File:Latin alphabet on a 14 segment display.gif

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 and lower case (with a few exceptions like "s").{{cn|date=February 2025}}

class="wikitable"

|+Hexadecimal Encoding of Latin Alphabet for 14-segment display

!Alphabet

!A

!B

!C

!D

!E

!F

!G

!H

!I

!J

!K

!L

!M

!N

Hex code

|0xF7

|0x128F

|0x39

|0x120F

|0xF9

|0xF1

|0xBD

|0xF6

|0x1209

|0x1E

|0x2470

|0x38

|0x536

|0x2136

class="wikitable"

!Alphabet

!O

!P

!Q

!R

!S

!T

!U

!V

!W

!X

!Y

!Z

Hex code

|0x3F

|0xF3

|0x203F

|0x20F3

|0x18D

|0x1201

|0x3E

|0xC30

|0x2836

|0x2D00

|0x1500

|0xC09

Applications

File:14 Segment LCD characters.jpg characters (the double quote is missing) on a 14-segment display]]

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 comma and period part making for a total of 16 segments.

Fourteen and sixteen-segment displays were used to produce alphanumeric characters on calculators and other embedded systems. Applications today include displays fitted to telephone Caller ID units, gymnasium equipment, VCRs, car stereos, microwave ovens, slot machines, 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 I. C. S. Reference Library Volume 4B, Scranton, International Textbook Company, 1908, no ISBN 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.[http://www.tubeclockdb.com/nixie-tubes/73-burroughs-5971-alphanumeric.html] Burroughs b5791 Tube Data They operated similarly to Nixie tubes but instead of the full-formed numeric shapes, used segments to make up numerals and letters.http://www.ineedcaffeine.com/content/the-burroughs-b7971/ {{Webarchive|url=https://web.archive.org/web/20150402132021/http://www.ineedcaffeine.com/content/the-burroughs-b7971/ |date=2015-04-02 }} 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.

See also

File:Common segment displays.svg-, 9-, 14-, and 16-segment displays shown side by side]]

References

{{Reflist|30em}}

External links

{{commons category-inline|Fourteen segment displays}}

{{Display technology}}

{{DEFAULTSORT:Fourteen-Segment Display}}

Category:Display technology