Display device

Image:Anzeigen.jpg|240px|thumb|Nixie tubes, LED display and VF display, top to bottom
A display device is an output device for presentation of information in visual or tactile form. When the input information that is supplied has an electrical signal the display is called an Electronic [visual display|electronic display].
Common applications for electronic visual displays are television sets or computer monitors.

Types of electronic displays

These are the technologies used to create the various displays in use today.

[Image:Digital clock changing numbers.jpg|thumb|right|300px|Digital clocks display changing numerals]
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. Common types are seven-segment displays which are used for numerals only, and alphanumeric fourteen-segment displays and sixteen-segment displays which can display numerals and Roman alphabet letters.

Cathode-ray tubes were also formerly widely used.

2-dimensional displays that cover a full area 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 for full-area 2-dimensional displays include:

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

Ticker tape
Split-flap display
Flip-disc display
Vane display
Rollsign
Tactile electronic displays are usually intended for the blind. They use electro-mechanical parts to dynamically update a tactile image 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.