What is the digital display called?

Display device for presentation of images, text, or video transmitted electronically

An electronic visual display, informally a screen, is a display device for presentation of images, text, or video transmitted electronically, without producing a permanent record. Electronic visual displays include television sets, computer monitors, and digital signage. By the above definition, an overhead projector (along with screen onto which the text, images, or video is projected) could reasonably be considered an electronic visual display since it is a display device for the presentation of an images, plain text, or video transmitted electronically without producing a permanent record. They are also ubiquitous in mobile computing applications like tablet computers, smartphones, and information appliances.

From the mid-2000s through to the early 2020s, flat-panel displays dominated the industry, as cathode-ray tubes (CRT) were phased out, especially for computer applications, and curved panels were not yet developed.

Types

[

edit

]

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

Additionally, CRTs were widely used in the past and microLED displays are under development.

Classification

[

edit

]

Electronic visual displays present visual information according to the electrical input signal (analog or digital) either by emitting light (then they are called active displays) or, alternatively, by modulating available light during the process of reflection or transmission (light modulators are called passive displays).

Display mode of observation

[

edit

]

Electronic visual displays can be observed directly (direct view display) or the displayed information can be projected to a screen (transmissive or reflective screen). This usually happens with smaller displays at a certain magnification.

A different kind of projection display is the class of "laser projection displays", where the image is built up sequentially either via line by line scanning or by writing one complete column at a time. For that purpose one beam is formed from three lasers operating at the primary colors, and this beam is scanned electro-mechanically (galvanometer scanner, micro-mirror array)) or electro-acousto-optically.

Layout of picture elements

[

edit

]

Depending on the shape and on the arrangement of the picture elements of a display, either fixed information can be displayed (symbols, signs), simple numerals (7-segment layout) or arbitrary shapes can be formed (dot-matrix displays).

Layout of picture elements Segmented displays
characters, numbers and symbols of fixed shape (may be multiplex addressed)
The following layouts are well known:
Seven-segment display
Fourteen-segment display
Sixteen-segment display Dot-matrix displays
sub-pixels are arranged in a regular 2-dimensional array
(multiplex addressing required); arbitrary shapes can be formed and displayed

Emission and control of colors

[

edit

]

Colors can be generated by selective emission, by selective absorption, transmission or by selective reflection.

Addressing modes

[

edit

]

Each sub-pixel of a display device must be selected (addressed) in order to be energized in a controlled way.

Addressing modes (selection of picture elements) direct addressing
each individual picture element has electrical connections to the driving electronics. multiplexed addressing
several picture elements have common electrical connections to the driving electronics,
e. g.. row and column electrodes when the picture elements are arranged in a two dimensional matrix. active matrix addressing
active electronic elements added in order to improve selection of picture elements.

• thin-film diodes (TFDs)
• thin-film transistors (TFTs)
  • amorphous silicon (a-Si)
  • polycrystalline silicon (p-Si)
  • monocrystalline silicon

passive matrix addressing
the nonlinearity of the display effect (e.g. LCD, LED)is used to realize the addressing of individual pixels in multiplex addressing. In this mode only a quite limited number of lines can be addressed. In the case of (STN-)LCDs this maximum is at ~240, but at the expense of a considerable reduction of contrast. The matrix of active electronic elements can be used in transmissive mode of operation (high transmittance required) or a non-transparent active matrix can be used for reflective LCDs (e.g. liquid crystal on silicon (LCOS)).|

Display driving modes

[

edit

]

Driving modes (activation of picture elements) voltage driving
activation of pixels by voltage (e.g. LCD field effects). If the current is low enough this mode may be the basis for displays with very low power requirements (e.g. μW for LCDs without backlight). current driving
activation of pixels by electric current (e.g. LED).

See also

[

edit

]

References

[

edit

]

1. ^

   Louis D. Silverstein, et al., Hybrid spatial-temporal color synthesis and its applications, JSID 14/1(2006), pp. 3–13

Further reading

[

edit

]

• Pochi Yeh, Claire Gu: "Optics of Liquid Crystal Displays", John Wiley & Sons 1999, 4.5. Conoscopy, pp. 139

Output device for presentation of information in visual form

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 that is supplied has an electrical signal the display is called an electronic display.

Common applications for electronic visual displays are television sets or computer monitors.

Types of electronic displays

[

edit

]

In use

[

edit

]

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

Segment displays

[

edit

]

Digital clocks display changing numerals The common segment displays shown side by side: 7-segment, 9-segment, 14-segment and 16-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. 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.

Other types

[

edit

]

Cathode-ray tubes were also formerly widely used.

Full-area 2-dimensional displays

[

edit

]

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 of full-area 2-dimensional displays

[

edit

]

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

Underlying technologies of full-area 2-dimensional displays

[

edit

]

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

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

Three-dimensional displays

[

edit

]

Mechanical types

[

edit

]

See also

[

edit

]

References

[

edit

]

• 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.