Display device

Display device

Nixie tubes, LED display and VF display, top to bottom.

A display device is an output device for presentation of information in visual[1] or tactile form (the latter used for example in tactile electronic displays for blind people).[2] When the input information is supplied as an electrical signal, the display is called an electronic display.

Common applications for electronic visual displays are televisions or computer monitors.


  • Segment displays 1
    • Underlying technologies 1.1
  • Full-area 2-dimensional displays 2
    • Applications 2.1
    • Underlying technologies 2.2
  • Three-dimensional 3
  • Mechanical types 4
  • History 5
  • See also 6
  • References 7
  • External links 8

Segment displays

Digital clocks display changing numbers.

Some displays can show only digits or alphanumeric characters. They are called segment displays, because they are composed of several segments that switch on and off to give appearance of desired glyph. The segments are usually single LEDs or liquid crystals. They are mostly used in digital watches and pocket calculators. There are several types:

The common segment displays shown side by side: 7-segment, 9-segment, 14-segment and 16-segment displays.

Underlying technologies

Full-area 2-dimensional displays

2-dimensional displays that cover a full area (usually a rectangle) are also called video displays, since it is the main modality of presenting video.


Full-area 2-dimensional displays are used in, for example:

Underlying technologies

Underlying technologies for full-area 2-dimensional displays include:

The multiplexed display technique is used to drive most display devices.


Mechanical types

  • Ticker tape (historical)
  • Split-flap display (or simply flap display)
  • Flip-disc display (or flip-dot display)
  • Rollsign
  • Tactile electronic displays (aka refreshable Braille display) are usually intended for the blind. They use electro-mechanical parts to dynamically update a tactile image (usually of text) so that the image may be felt by the fingers.
    • Optacon, using metal rods instead of light in order to convey images to blind people by tactile sensation.
  • Idiot lights, the "Check Engine" light on an automobile dashboard is the quintessential idiot light, giving only the information that something is amiss, but not what particular subsystem or component, nor how urgent the problem is. Neither does it give any information about issues that may be still within acceptable limits, but trending towards failure.


In the history of display technology, a variety of display devices and technologies have been used.

See also


  1. ^ Lemley, Linda. "Chapter 6: Output". Discovering Computers. University of West Florida. Retrieved 3 June 2012. 
  2. ^ "Accommodations For Vision Disabilities". Energy.gov. Office of the Chief information Officer. Retrieved 3 June 2012. 

External links

  • Society for Information Display - An international professional organization dedicated to the study of display technology
  • University of Waterloo Stratford Campus - A university that offers students the opportunity to display their work on the school's 3-storey Christie MicroTile wall.