A display device is an output device for presentation of information in visual or tactile form (the latter used for example in tactile electronic displays for blind people). When the input information is supplied has an electrical signal, the display is called an electronic display.
Common applications for electronic visual displays are televisions or computer monitors.
Segment displays
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:
Seven-segment display (most common, digits only)
Fourteen-segment display
Sixteen-segment display
HD44780 LCD controller a widely accepted protocol for LCDs.
Underlying technologies
Incandescent filaments
Vacuum fluorescent display
Cold cathode gas discharge
Light-emitting diode (LED)
Liquid crystal display (LCD)
Physical vane with electromagnetic activation
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.
Applications
Full-area 2-dimensional displays are used in, for example:
Television sets
Computer monitors
Head-mounted display
Broadcast reference monitor
Medical monitors
Underlying technologies
Underlying technologies for full-area 2-dimensional displays include:
The multiplexed display technique is used to drive most display devices.
Three-dimensional
Swept-volume display
Varifocal mirror display
Emissive volume display
Laser display
Holographic display
Light field displays
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.
History
In the history of display technology, a variety of display devices and technologies have been used.
