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A flat-panel display (FPD) is an electronic
display used to display visual content such as text or images. It is present in consumer, medical, transportation, and industrial equipment.
Flat-panel displays are thin, lightweight, provide better linearity and are capable of higher resolution than typical consumer-grade TVs from earlier eras. They are usually less than thick. While the highest resolution for consumer-grade CRT televisions was
1080i
1080i (also known as Full HD or BT.709) is a combination of frame resolution and scan type. 1080i is used in high-definition television (HDTV) and high-definition video. The number "1080" refers to the number of horizontal lines on the scre ...
, many flat-panel displays in the 2020s are capable of 1080p and
4K resolution.
In the 2010s, portable consumer electronics such as laptops, mobile phones, and portable cameras have used flat-panel displays since they consume less power and are lightweight. As of 2016, flat-panel displays have almost completely replaced CRT displays.
Most 2010s-era flat-panel displays use LCD or
light-emitting diode
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (co ...
(LED) technologies, sometimes combined. Most LCD screens are
back-lit with color filters used to display colors. In many cases, flat-panel displays are combined with
touch screen
A touchscreen or touch screen is the assembly of both an input ('touch panel') and output ('display') device. The touch panel is normally layered on the top of an electronic visual display of an information processing system. The display is ofte ...
technology, which allows the user to interact with the display in a natural manner. For example, modern smartphone displays often use
OLED
An organic light-emitting diode (OLED or organic LED), also known as organic electroluminescent (organic EL) diode, is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light i ...
panels, with
capacitive touch screen
A touchscreen or touch screen is the assembly of both an input ('touch panel') and output ('display') device. The touch panel is normally layered on the top of an electronic visual display of an information processing system. The display is ofte ...
s.
Flat-panel displays can be divided into two display device categories: volatile and static. The former requires that pixels be periodically electronically refreshed to retain their state (e.g.
liquid-crystal displays (LCD)), and can only show an image when it has power. On the other hand, static flat-panel displays rely on materials whose color states are bistable, such as displays that make use of
e-ink technology, and as such retain content even when power is removed.
History
The first engineering proposal for a flat-panel TV was by
General Electric
General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable en ...
in 1954 as a result of its work on radar monitors. The publication of their findings gave all the basics of future flat-panel TVs and monitors. But GE did not continue with the R&D required and never built a working flat panel at that time. The first production flat-panel display was the
Aiken tube, developed in the early 1950s and produced in limited numbers in 1958. This saw some use in military systems as a
heads up display
A head-up display, or heads-up display, also known as a HUD (), is any transparent display that presents data without requiring users to look away from their usual viewpoints. The origin of the name stems from a pilot being able to view informa ...
and as an oscilloscope monitor, but conventional technologies overtook its development. Attempts to commercialize the system for home television use ran into continued problems and the system was never released commercially.
The
Philco Predicta featured a relatively flat (for its day) cathode ray tube setup and would be the first commercially released "flat panel" upon its launch in 1958; the Predicta was a commercial failure. The
plasma display panel
A plasma display panel (PDP) is a type of flat panel display that uses small cells containing plasma: ionized gas that responds to electric fields. Plasma televisions were the first large (over 32 inches diagonal) flat panel displays to be release ...
was invented in 1964 at the
University of Illinois
The University of Illinois Urbana-Champaign (U of I, Illinois, University of Illinois, or UIUC) is a public land-grant research university in Illinois in the twin cities of Champaign and Urbana. It is the flagship institution of the Univer ...
, according to The History of Plasma Display Panels.
Liquid-crystal Displays (LCDs)
The
MOSFET (metal-oxide-semiconductor field-effect transistor, or MOS transistor) was invented by
Mohamed M. Atalla
Mohamed M. Atalla ( ar, محمد عطاالله; August 4, 1924 – December 30, 2009) was an Egyptian-American engineer, physicist, cryptographer, inventor and entrepreneur. He was a semiconductor pioneer who made important contributions to ...
and
Dawon Kahng
Dawon Kahng ( ko, 강대원; May 4, 1931 – May 13, 1992) was a Korean-American electrical engineer and inventor, known for his work in solid-state electronics. He is best known for inventing the MOSFET (metal–oxide–semiconductor field-effe ...
at
Bell Labs
Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984),
then AT&T Bell Laboratories (1984–1996)
and Bell Labs Innovations (1996–2007),
is an American industrial Research and development, research and scientific developm ...
in 1959,
and presented in 1960. Building on their work,
Paul K. Weimer at
RCA
The RCA Corporation was a major American electronics company, which was founded as the Radio Corporation of America in 1919. It was initially a patent trust owned by General Electric (GE), Westinghouse, AT&T Corporation and United Fruit Comp ...
developed the
thin-film transistor
A thin-film transistor (TFT) is a special type of field-effect transistor (FET) where the transistor is thin relative to the plane of the device. TFTs are grown on a supporting (but non-conducting) substrate. A common substrate is glass, becaus ...
(TFT) in 1962. It was a type of MOSFET distinct from the standard bulk MOSFET.
The idea of a TFT-based LCD was conceived by
Bernard J. Lechner of
RCA Laboratories
The RCA Corporation was a major American electronics company, which was founded as the Radio Corporation of America in 1919. It was initially a patent trust owned by General Electric (GE), Westinghouse, AT&T Corporation and United Fruit Comp ...
in 1968.
B.J. Lechner, F.J. Marlowe, E.O. Nester and J. Tults demonstrated the concept in 1968 with a
dynamic scattering
The dynamical theory of diffraction describes the interaction of waves with a regular lattice. The wave fields traditionally described are X-rays, neutrons or electrons and the regular lattice are atomic crystal structures or nanometer-scale multi ...
LCD that used standard discrete MOSFETs.
The first
active-matrix Active matrix is a type of addressing scheme used in flat panel displays. In this method of switching individual elements (pixels), each pixel is attached to a transistor and capacitor ''actively'' maintaining the pixel state while other pixels are ...
addressed
electroluminescent display (ELD) was made using TFTs by
T. Peter Brody's Thin-Film Devices department at
Westinghouse Electric Corporation
The Westinghouse Electric Corporation was an American manufacturing company founded in 1886 by George Westinghouse. It was originally named "Westinghouse Electric & Manufacturing Company" and was renamed "Westinghouse Electric Corporation" in ...
in 1968. In 1973, Brody, J. A. Asars and G. D. Dixon at
Westinghouse Research Laboratories demonstrated the first
thin-film-transistor liquid-crystal display
A thin-film-transistor liquid-crystal display (TFT LCD) is a variant of a liquid-crystal display that uses thin-film-transistor technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD, in con ...
(TFT LCD).
Brody and Fang-Chen Luo demonstrated the first flat
active-matrix liquid-crystal display
An active-matrix liquid-crystal display (AMLCD) is a type of flat-panel display, the only viable technology for high-resolution TVs, computer monitors, notebook computers, tablet computers and smartphones with an LCD screen, due to low weight, ...
(AM LCD) using TFTs in 1974.
By 1982,
pocket LCD TVs based on LCD technology were developed in Japan. The 2.1-inch
Epson
Seiko Epson Corporation, or simply known as Epson, is a Japanese multinational electronics company and one of the world's largest manufacturers of computer printers and information- and imaging-related equipment. Headquartered in Suwa, Nagano ...
ET-10
''Epson Elf'' was the first color LCD pocket TV, released in 1984. In 1988, a
Sharp
Sharp or SHARP may refer to:
Acronyms
* SHARP (helmet ratings) (Safety Helmet Assessment and Rating Programme), a British motorcycle helmet safety rating scheme
* Self Help Addiction Recovery Program, a charitable organisation founded in 19 ...
research team led by engineer T. Nagayasu demonstrated a 14-inch full-color LCD display,
which convinced the
electronics industry that LCD would eventually replace CRTs as the standard television
display technology
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 that is supplied has an electrical signal the ...
.
, all modern
high-resolution
Image resolution is the detail an image holds. The term applies to digital images, film images, and other types of images. "Higher resolution" means more image detail.
Image resolution can be measured in various ways. Resolution quantifies how cl ...
and high-quality
electronic visual display
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 monito ...
devices use TFT-based active-matrix displays.
LED displays
The first usable LED display was developed by
Hewlett-Packard (HP) and introduced in 1968.
It was the result of
research and development (R&D) on practical
LED technology between 1962 and 1968, by a research team under Howard C. Borden, Gerald P. Pighini, and
Mohamed M. Atalla
Mohamed M. Atalla ( ar, محمد عطاالله; August 4, 1924 – December 30, 2009) was an Egyptian-American engineer, physicist, cryptographer, inventor and entrepreneur. He was a semiconductor pioneer who made important contributions to ...
, at HP Associates and
HP Labs. In February 1969, they introduced the HP Model 5082-7000 Numeric Indicator.
It was the first alphanumeric LED display, and was a revolution in
digital display
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 that is supplied has an electrical signal t ...
technology, replacing the
Nixie tube
A Nixie tube ( ), or cold cathode display, is an electronic device used for displaying numerals or other information using glow discharge.
The glass tube contains a wire-mesh anode and multiple cathodes, shaped like numerals or other symbo ...
for numeric displays and becoming the basis for later LED displays. In 1977, James P Mitchell prototyped and later demonstrated what was perhaps the earliest monochromatic flat panel LED television display.
Ching W. Tang
Ching Wan Tang (; born July 23, 1947) is a Hong Kong Americans, Hong Kong–American Physical chemistry, physical chemist. He was inducted into the National Inventors Hall of Fame in 2018 for inventing OLED (together with Steven Van Slyke), and ...
and
Steven Van Slyke
Steven Van Slyke (born July 19, 1956) is an American chemist, best known for his co-invention of the Organic Light Emitting Diode (OLED) and his contributions to the commercial development of OLED displays. Van Slyke is currently the Chief Techn ...
at
Eastman Kodak built the first practical
organic LED
An organic light-emitting diode (OLED or organic LED), also known as organic electroluminescent (organic EL) diode, is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light i ...
(OLED) device in 1987.
In 2003,
Hynix
SK hynix Inc. is a South Korean supplier of dynamic random-access memory (DRAM) chips and flash memory chips. Hynix is the world's second-largest memory chipmaker (after Samsung Electronics) and the world's third-largest semiconductor company. ...
produced an organic EL driver capable of lighting in 4,096 colors.
In 2004, the
Sony
, commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professiona ...
Qualia
In philosophy of mind, qualia ( or ; singular form: quale) are defined as individual instances of subjective, conscious experience. The term ''qualia'' derives from the Latin neuter plural form (''qualia'') of the Latin adjective '' quālis'' () ...
005 was the first
LED-backlit LCD
An LED-backlit LCD is a liquid-crystal display that uses LEDs for backlighting instead of traditional cold cathode fluorescent (CCFL) backlighting. LED-backlit displays use the same TFT LCD (thin-film-transistor liquid-crystal display) techno ...
display. The
Sony XEL-1
The XEL-1 is the world's first organic light-emitting diode (OLED) television, designed by Sony in 2007 and produced for sale the following year. It was also the world's thinnest television during its production, at 3 mm. It has a screen siz ...
, released in 2007, was the first OLED television.
[Sony XEL-1:The world's first OLED TV](_blank)
, OLED-Info.com (17 November 2008).
Common types
Liquid-crystal display (LCD)
![Expo line passenger information display](https://upload.wikimedia.org/wikipedia/commons/0/02/Expo_line_passenger_information_display..jpg)
Field-effect LCDs are lightweight, compact, portable, cheap, more reliable, and easier on the eyes than CRT screens. LCD screens use a thin layer of liquid crystal, a liquid that exhibits crystalline properties. It is sandwiched between two glass plates carrying transparent electrodes. Two polarizing films are placed at each side of the LCD. By generating a controlled electric field between electrodes, various segments or pixels of the liquid crystal can be activated, causing changes in their polarizing properties. These polarizing properties depend on the alignment of the liquid-crystal layer and the specific field-effect used, being either
Twisted Nematic (TN),
In-Plane Switching
IPS (in-plane switching) is a screen technology for liquid-crystal displays (LCDs). In IPS, a layer of liquid crystals is sandwiched between two glass surfaces. The liquid crystal molecules are aligned parallel to those surfaces in predetermined ...
(IPS) or
Vertical Alignment (VA). Color is produced by applying appropriate color filters (red, green and blue) to the individual subpixels. LCD displays are used in various electronics like watches, calculators, mobile phones, TVs, computer monitors and laptops screens etc.
LED-LCD
Most earlier large LCD screens were back-lit using a number of CCFL (cold-cathode fluorescent lamps). However, small pocket size devices almost always used LEDs as their illumination source. With the improvement of LEDs, almost all new displays are now equipped with
LED backlight technology. The image is still generated by the LCD layer.
Plasma panel
A plasma display consists of two glass plates separated by a thin gap filled with a gas such as
neon. Each of these plates has several parallel electrodes running across it. The electrodes on the two plates are at right angles to each other. A voltage applied between the two electrodes one on each plate causes a small segment of gas at the two electrodes to glow. The glow of gas segments is maintained by a lower voltage that is continuously applied to all electrodes. By 2010, consumer plasma displays had been discontinued by numerous manufacturers.
Electroluminescent panel
In an
electroluminescent display (ELD), the image is created by applying electrical signals to the plates which make the phosphor glow.
Organic light-emitting diode
An
OLED
An organic light-emitting diode (OLED or organic LED), also known as organic electroluminescent (organic EL) diode, is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light i ...
(organic light-emitting diode) is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound which emits light in response to an electric current. This layer of organic semiconductor is situated between two electrodes; typically, at least one of these electrodes is transparent. OLEDs are used to create digital displays in devices such as television screens, computer monitors, portable systems such as mobile phones, handheld game consoles and PDAs.
Quantum-dot light-emitting diode
QLED or quantum dot LED is a flat panel display technology introduced by Samsung under this trademark. Other television set manufacturers such as
Sony
, commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professiona ...
have used the same technology to enhance the backlighting of LCD TVs already in 2013.
''LG leaps quantum dot rivals with new TV.''
CNET, 16 December 2014. Retrieved 21 October 2017 Quantum dots create their own unique light when illuminated by a light source of shorter wavelength
In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats.
It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, t ...
such as blue LEDs. This type of LED TV enhances the colour gamut
In color reproduction, including computer graphics and photography, the gamut, or color gamut , is a certain ''complete subset'' of colors. The most common usage refers to the subset of colors which can be accurately represented in a given circ ...
of LCD panels, where the image is still generated by the LCD. In the view of Samsung, quantum dot displays for large-screen TVs are expected to become more popular than the OLED displays in the coming years; Firms like Nanoco and Nanosys compete to provide the QD materials. In the meantime, Samsung Galaxy
Samsung Galaxy (, stylised as SΛMSUNG Galaxy since 2015 (except Japan where it omits the Samsung branding), previously stylised as Samsung GALAXY; abbreviated as SG) is a series of computing and mobile computing devices that are designed, m ...
devices such as smartphones are still equipped with OLED displays manufactured by Samsung as well. Samsung explains on their website that the QLED TV they produce can determine what part of the display needs more or less contrast. Samsung also announced a partnership with Microsoft that will promote the new Samsung QLED TV.
Volatile
Volatile displays require that pixels be periodically refreshed to retain their state, even for a static image. As such, a volatile screen needs electrical power, either from mains electricity
Mains electricity or utility power, power grid, domestic power, and wall power, or in some parts of Canada as hydro, is a general-purpose alternating-current (AC) electric power supply. It is the form of electrical power that is delivered to h ...
(being plugged into a wall socket) or a battery to maintain an image on the display or change the image. This refresh typically occurs many times a second. If this is not done, for example, if there is a power outage
A power outage (also called a powercut, a power out, a power failure, a power blackout, a power loss, or a blackout) is the loss of the electrical power network supply to an end user.
There are many causes of power failures in an electricity ...
, the pixels will gradually lose their coherent state, and the image will "fade" from the screen.
Examples
The following flat-display technologies have been commercialized in 1990s to 2010s:
* Plasma display panel (PDP)
* Active-matrix liquid-crystal display (AMLCD)
* Rear projection
Rear projection (background projection, process photography, etc.) is one of many in-camera effects cinematic techniques
in film production for combining foreground performances with pre-filmed backgrounds. It was widely used for many years in ...
: Digital Light Processing
Digital Light Processing (DLP) is a set of chipsets based on optical micro-electro-mechanical technology that uses a digital micromirror device. It was originally developed in 1987 by Larry Hornbeck of Texas Instruments. While the DLP imagin ...
(DLP), LCD, LCOS
* Electronic paper
Electronic paper, also sometimes electronic ink, e-ink or electrophoretic display, are display devices that mimic the appearance of ordinary ink on paper. Unlike conventional flat panel displays that emit light, an electronic paper display ...
: E Ink
E Ink (electronic ink) is a brand of electronic paper (e-paper) display technology commercialized by the E Ink Corporation, which was co-founded in 1997 by MIT undergraduates JD Albert and Barrett Comiskey, MIT Media Lab professor Joseph Jacobson ...
, Gyricon
* Light-emitting diode display (LED)
* Active-matrix organic light-emitting diode
AMOLED (active-matrix organic light-emitting diode, ) is a type of OLED display device technology. OLED describes a specific type of thin-film-display technology in which organic compounds form the electroluminescent material, and active matrix ...
(AMOLED)
* Quantum dot display
A quantum dot display is a display device that uses quantum dots (QD), semiconductor nanocrystals which can produce pure monochromatic red, green, and blue light.
''Photo-emissive'' quantum dot particles are used in LCD backlights and/or disp ...
(QLED)
Technologies that were extensively researched, but their commercialization was limited or has been ultimately abandoned:
* Active-matrix electroluminescent display (ELD)
* Interferometric modulator display Interferometric modulator display (IMOD, trademarked mirasol) is a technology used in electronic visual displays that can create various colors via interference of reflected light. The color is selected with an electrically switched light modulato ...
(IMOD)
* Field emission display (FED)
* Surface-conduction electron-emitter display (SED, SED-TV)
Static
Static flat-panel displays rely on materials whose color states are bistable. This means that the image they hold requires no energy to maintain, but instead requires energy to change. This results in a much more energy-efficient display, but with a tendency toward slow refresh rates which are undesirable in an interactive display. Bistable flat-panel displays are beginning deployment in limited applications ( cholesteric liquid-crystal displays, manufactured by Magink, in outdoor advertising; electrophoretic displays in e-book
An ebook (short for electronic book), also known as an e-book or eBook, is a book publication made available in digital form, consisting of text, images, or both, readable on the flat-panel display of computers or other electronic devices. Alt ...
reader devices from Sony and iRex; anlabels; interferometric modulator display Interferometric modulator display (IMOD, trademarked mirasol) is a technology used in electronic visual displays that can create various colors via interference of reflected light. The color is selected with an electrically switched light modulato ...
s in a smartwatch).
See also
* Computer monitor
* Display motion blur
Display motion blur, also called ''HDTV blur'' and ''LCD motion blur'', refers to several visual artifacts (anomalies or unintended effects affecting still or moving images) that are frequently found on modern consumer high-definition television se ...
* Electronic paper
Electronic paper, also sometimes electronic ink, e-ink or electrophoretic display, are display devices that mimic the appearance of ordinary ink on paper. Unlike conventional flat panel displays that emit light, an electronic paper display ...
* FPD-Link
Flat Panel Display Link, more commonly referred to as FPD-Link, is the original high-speed digital video interface created in 1996 by National Semiconductor (now within Texas Instruments). It is a free and open standard for connecting the output ...
* Flexible display
A flexible display or rollable display is an electronic visual display which is flexible in nature, as opposed to the traditional flat screen displays used in most electronic devices. In recent years there has been a growing interest from nume ...
* Large-screen television technology
Large-screen television technology (colloquially big-screen TV) developed rapidly in the late 1990s and 2000s. Prior to the development of thin-screen technologies, rear-projection television was standard for larger displays, and jumbotron, a n ...
* LCD
* LED-backlit LCD television
An LED-backlit LCD is a liquid-crystal display that uses LEDs for backlighting instead of traditional cold cathode fluorescent (CCFL) backlighting. LED-backlit displays use the same TFT LCD (thin-film-transistor liquid-crystal display) techno ...
* List of flat panel display manufacturers
Flat-panel displays are thin panels of glass or plastic used for electronically displaying text, images, or video. Liquid crystal displays (LCD), OLED (organic light emitting diode) and microLED displays are not quite the same; since LCD uses a ...
* MicroLED
microLED, also known as micro-LED, mLED or µLED, first invented in 2000 by the research group of Hongxing Jiang and Jingyu Lin of Texas Tech University while they were at Kansas State University, is an emerging flat-panel display technology. ...
* Mobile display
* OLED
An organic light-emitting diode (OLED or organic LED), also known as organic electroluminescent (organic EL) diode, is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light i ...
* Plasma display panel
A plasma display panel (PDP) is a type of flat panel display that uses small cells containing plasma: ionized gas that responds to electric fields. Plasma televisions were the first large (over 32 inches diagonal) flat panel displays to be release ...
* Quantum dot display
A quantum dot display is a display device that uses quantum dots (QD), semiconductor nanocrystals which can produce pure monochromatic red, green, and blue light.
''Photo-emissive'' quantum dot particles are used in LCD backlights and/or disp ...
* Sony Watchman
The Sony Watchman is a line of portable pocket televisions trademarked and produced by Sony. The line was introduced in 1982 and discontinued in 2000.
Its name came from a portmanteau formed of "Watch" (watching television) and "man" from Sony ...
* Stereoscopy 3D displays requiring no special glasses
* Touch panel
A touchscreen or touch screen is the assembly of both an input ('touch panel') and output ('display') device. The touch panel is normally layered on the top of an electronic visual display of an information processing system. The display is often ...
* Transparent display
References
{{Authority control
American inventions
Display technology
Computer hardware
Television technology
Consumer electronics
Industrial equipment