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Glass substrate with ITO electrodes. The shapes of these electrodes will determine the shapes that will appear when the LCD is switched ON. Vertical ridges etched on the surface are smooth.

A liquid-crystal display (LCD) is a flat-panel display or other electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers. Liquid crystals do not emit light directlybacklight or reflector to produce images in color or monochrome.seven-segment displays, as in a digital clock, are all good examples of devices with these displays. They use the same basic technology, except that arbitrary images are made from a matrix of small pixels, while other displays have larger elements. LCDs can either be normally on (positive) or off (negative), depending on the polarizer arrangement. For example, a character positive LCD with a backlight will have black lettering on a background that is the color of the backlight, and a character negative LCD will have a black background with the letters being of the same color as the backlight. Optical filters are added to white on blue LCDs to give them their characteristic appearance.

LCDs are used in a wide range of applications, including LCD televisions, computer monitors, instrument panels, aircraft cockpit displays, and indoor and outdoor signage. Small LCD screens are common in LCD projectors and portable consumer devices such as digital cameras, watches, calculators, and mobile telephones, including smartphones. LCD screens have replaced heavy, bulky and less energy-efficient cathode-ray tube (CRT) displays in nearly all applications. The phosphors used in CRTs make them vulnerable to image burn-in when a static image is displayed on a screen for a long time, e.g., the table frame for an airline flight schedule on an indoor sign. LCDs do not have this weakness, but are still susceptible to image persistence.

Each pixel of an LCD typically consists of a layer of molecules aligned between two transparent electrodes, often made of Indium-Tin oxide (ITO) and two polarizing filters (parallel and perpendicular polarizers), the axes of transmission of which are (in most of the cases) perpendicular to each other. Without the liquid crystal between the polarizing filters, light passing through the first filter would be blocked by the second (crossed) polarizer. Before an electric field is applied, the orientation of the liquid-crystal molecules is determined by the alignment at the surfaces of electrodes. In a twisted nematic (TN) device, the surface alignment directions at the two electrodes are perpendicular to each other, and so the molecules arrange themselves in a helical structure, or twist. This induces the rotation of the polarization of the incident light, and the device appears gray. If the applied voltage is large enough, the liquid crystal molecules in the center of the layer are almost completely untwisted and the polarization of the incident light is not rotated as it passes through the liquid crystal layer. This light will then be mainly polarized perpendicular to the second filter, and thus be blocked and the pixel will appear black. By controlling the voltage applied across the liquid crystal layer in each pixel, light can be allowed to pass through in varying amounts thus constituting different levels of gray.

The chemical formula of the liquid crystals used in LCDs may vary. Formulas may be patented.Sharp Corporation. The patent that covered that specific mixture expired.

Most color LCD systems use the same technique, with color filters used to generate red, green, and blue subpixels. The LCD color filters are made with a photolithography process on large glass sheets that are later glued with other glass sheets containing a TFT array, spacers and liquid crystal, creating several color LCDs that are then cut from one another and laminated with polarizer sheets. Red, green, blue and black photoresists (resists) are used. All resists contain a finely ground powdered pigment, with particles being just 40 nanometers across. The black resist is the first to be applied; this will create a black grid (known in the industry as a black matrix) that will separate red, green and blue subpixels from one another, increasing contrast ratios and preventing light from leaking from one subpixel onto other surrounding subpixels.Super-twisted nematic LCD, where the variable twist between tighter-spaced plates causes a varying double refraction birefringence, thus changing the hue.

LCD in a Texas Instruments calculator with top polarizer removed from device and placed on top, such that the top and bottom polarizers are perpendicular. As a result, the colors are inverted.

The optical effect of a TN device in the voltage-on state is far less dependent on variations in the device thickness than that in the voltage-off state. Because of this, TN displays with low information content and no backlighting are usually operated between crossed polarizers such that they appear bright with no voltage (the eye is much more sensitive to variations in the dark state than the bright state). As most of 2010-era LCDs are used in television sets, monitors and smartphones, they have high-resolution matrix arrays of pixels to display arbitrary images using backlighting with a dark background. When no image is displayed, different arrangements are used. For this purpose, TN LCDs are operated between parallel polarizers, whereas IPS LCDs feature crossed polarizers. In many applications IPS LCDs have replaced TN LCDs, particularly in smartphones. Both the liquid crystal material and the alignment layer material contain ionic compounds. If an electric field of one particular polarity is applied for a long period of time, this ionic material is attracted to the surfaces and degrades the device performance. This is avoided either by applying an alternating current or by reversing the polarity of the electric field as the device is addressed (the response of the liquid crystal layer is identical, regardless of the polarity of the applied field).

Displays for a small number of individual digits or fixed symbols (as in digital watches and pocket calculators) can be implemented with independent electrodes for each segment.alphanumeric or variable graphics displays are usually implemented with pixels arranged as a matrix consisting of electrically connected rows on one side of the LC layer and columns on the other side, which makes it possible to address each pixel at the intersections. The general method of matrix addressing consists of sequentially addressing one side of the matrix, for example by selecting the rows one-by-one and applying the picture information on the other side at the columns row-by-row. For details on the various matrix addressing schemes see passive-matrix and active-matrix addressed LCDs.

LCDs are manufactured in cleanrooms borrowing techniques from semiconductor manufacturing and using large sheets of glass whose size has increased over time. Several displays are manufactured at the same time, and then cut from the sheet of glass, also known as the mother glass or LCD glass substrate. The increase in size allows more displays or larger displays to be made, just like with increasing wafer sizes in semiconductor manufacturing. The glass sizes are as follows:

Until Gen 8, manufacturers would not agree on a single mother glass size and as a result, different manufacturers would use slightly different glass sizes for the same generation. Some manufacturers have adopted Gen 8.6 mother glass sheets which are only slightly larger than Gen 8.5, allowing for more 50 and 58 inch LCDs to be made per mother glass, specially 58 inch LCDs, in which case 6 can be produced on a Gen 8.6 mother glass vs only 3 on a Gen 8.5 mother glass, significantly reducing waste.AGC Inc., Corning Inc., and Nippon Electric Glass.

In 1922, Georges Friedel described the structure and properties of liquid crystals and classified them in three types (nematics, smectics and cholesterics). In 1927, Vsevolod Frederiks devised the electrically switched light valve, called the Fréedericksz transition, the essential effect of all LCD technology. In 1936, the Marconi Wireless Telegraph company patented the first practical application of the technology, "The Liquid Crystal Light Valve". In 1962, the first major English language publication Molecular Structure and Properties of Liquid Crystals was published by Dr. George W. Gray.RCA found that liquid crystals had some interesting electro-optic characteristics and he realized an electro-optical effect by generating stripe-patterns in a thin layer of liquid crystal material by the application of a voltage. This effect is based on an electro-hydrodynamic instability forming what are now called "Williams domains" inside the liquid crystal.

In the late 1960s, pioneering work on liquid crystals was undertaken by the UK"s Royal Radar Establishment at Malvern, England. The team at RRE supported ongoing work by George William Gray and his team at the University of Hull who ultimately discovered the cyanobiphenyl liquid crystals, which had correct stability and temperature properties for application in LCDs.

The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968.dynamic scattering mode (DSM) LCD that used standard discrete MOSFETs.

On December 4, 1970, the twisted nematic field effect (TN) in liquid crystals was filed for patent by Hoffmann-LaRoche in Switzerland, (Swiss patent No. 532 261) with Wolfgang Helfrich and Martin Schadt (then working for the Central Research Laboratories) listed as inventors.Brown, Boveri & Cie, its joint venture partner at that time, which produced TN displays for wristwatches and other applications during the 1970s for the international markets including the Japanese electronics industry, which soon produced the first digital quartz wristwatches with TN-LCDs and numerous other products. James Fergason, while working with Sardari Arora and Alfred Saupe at Kent State University Liquid Crystal Institute, filed an identical patent in the United States on April 22, 1971.ILIXCO (now LXD Incorporated), produced LCDs based on the TN-effect, which soon superseded the poor-quality DSM types due to improvements of lower operating voltages and lower power consumption. Tetsuro Hama and Izuhiko Nishimura of Seiko received a US patent dated February 1971, for an electronic wristwatch incorporating a TN-LCD.

In 1972, the concept of the active-matrix thin-film transistor (TFT) liquid-crystal display panel was prototyped in the United States by T. Peter Brody"s team at Westinghouse, in Pittsburgh, Pennsylvania.Westinghouse Research Laboratories demonstrated the first thin-film-transistor liquid-crystal display (TFT LCD).high-resolution and high-quality electronic visual display devices use TFT-based active matrix displays.active-matrix liquid-crystal display (AM LCD) in 1974, and then Brody coined the term "active matrix" in 1975.

In 1972 North American Rockwell Microelectronics Corp introduced the use of DSM LCDs for calculators for marketing by Lloyds Electronics Inc, though these required an internal light source for illumination.Sharp Corporation followed with DSM LCDs for pocket-sized calculators in 1973Seiko and its first 6-digit TN-LCD quartz wristwatch, and Casio"s "Casiotron". Color LCDs based on Guest-Host interaction were invented by a team at RCA in 1968.TFT LCDs similar to the prototypes developed by a Westinghouse team in 1972 were patented in 1976 by a team at Sharp consisting of Fumiaki Funada, Masataka Matsuura, and Tomio Wada,

In 1983, researchers at Brown, Boveri & Cie (BBC) Research Center, Switzerland, invented the passive matrix-addressed LCDs. H. Amstutz et al. were listed as inventors in the corresponding patent applications filed in Switzerland on July 7, 1983, and October 28, 1983. Patents were granted in Switzerland CH 665491, Europe EP 0131216,

The first color LCD televisions were developed as handheld televisions in Japan. In 1980, Hattori Seiko"s R&D group began development on color LCD pocket televisions.Seiko Epson released the first LCD television, the Epson TV Watch, a wristwatch equipped with a small active-matrix LCD television.dot matrix TN-LCD in 1983.Citizen Watch,TFT LCD.computer monitors and LCD televisions.3LCD projection technology in the 1980s, and licensed it for use in projectors in 1988.compact, full-color LCD projector.

In 1990, under different titles, inventors conceived electro optical effects as alternatives to twisted nematic field effect LCDs (TN- and STN- LCDs). One approach was to use interdigital electrodes on one glass substrate only to produce an electric field essentially parallel to the glass substrates.Germany by Guenter Baur et al. and patented in various countries.Hitachi work out various practical details of the IPS technology to interconnect the thin-film transistor array as a matrix and to avoid undesirable stray fields in between pixels.

Hitachi also improved the viewing angle dependence further by optimizing the shape of the electrodes (Super IPS). NEC and Hitachi become early manufacturers of active-matrix addressed LCDs based on the IPS technology. This is a milestone for implementing large-screen LCDs having acceptable visual performance for flat-panel computer monitors and television screens. In 1996, Samsung developed the optical patterning technique that enables multi-domain LCD. Multi-domain and In Plane Switching subsequently remain the dominant LCD designs through 2006.South Korea and Taiwan,

In 2007 the image quality of LCD televisions surpassed the image quality of cathode-ray-tube-based (CRT) TVs.LCD TVs were projected to account 50% of the 200 million TVs to be shipped globally in 2006, according to Displaybank.Toshiba announced 2560 × 1600 pixels on a 6.1-inch (155 mm) LCD panel, suitable for use in a tablet computer,

In 2016, Panasonic developed IPS LCDs with a contrast ratio of 1,000,000:1, rivaling OLEDs. This technology was later put into mass production as dual layer, dual panel or LMCL (Light Modulating Cell Layer) LCDs. The technology uses 2 liquid crystal layers instead of one, and may be used along with a mini-LED backlight and quantum dot sheets.

Since LCDs produce no light of their own, they require external light to produce a visible image.backlight. Active-matrix LCDs are almost always backlit.Transflective LCDs combine the features of a backlit transmissive display and a reflective display.

CCFL: The LCD panel is lit either by two cold cathode fluorescent lamps placed at opposite edges of the display or an array of parallel CCFLs behind larger displays. A diffuser (made of PMMA acrylic plastic, also known as a wave or light guide/guiding plateinverter to convert whatever DC voltage the device uses (usually 5 or 12 V) to ≈1000 V needed to light a CCFL.

EL-WLED: The LCD panel is lit by a row of white LEDs placed at one or more edges of the screen. A light diffuser (light guide plate, LGP) is then used to spread the light evenly across the whole display, similarly to edge-lit CCFL LCD backlights. The diffuser is made out of either PMMA plastic or special glass, PMMA is used in most cases because it is rugged, while special glass is used when the thickness of the LCD is of primary concern, because it doesn"t expand as much when heated or exposed to moisture, which allows LCDs to be just 5mm thick. Quantum dots may be placed on top of the diffuser as a quantum dot enhancement film (QDEF, in which case they need a layer to be protected from heat and humidity) or on the color filter of the LCD, replacing the resists that are normally used.

WLED array: The LCD panel is lit by a full array of white LEDs placed behind a diffuser behind the panel. LCDs that use this implementation will usually have the ability to dim or completely turn off the LEDs in the dark areas of the image being displayed, effectively increasing the contrast ratio of the display. The precision with which this can be done will depend on the number of dimming zones of the display. The more dimming zones, the more precise the dimming, with less obvious blooming artifacts which are visible as dark grey patches surrounded by the unlit areas of the LCD. As of 2012, this design gets most of its use from upscale, larger-screen LCD televisions.

RGB-LED array: Similar to the WLED array, except the panel is lit by a full array of RGB LEDs. While displays lit with white LEDs usually have a poorer color gamut than CCFL lit displays, panels lit with RGB LEDs have very wide color gamuts. This implementation is most popular on professional graphics editing LCDs. As of 2012, LCDs in this category usually cost more than $1000. As of 2016 the cost of this category has drastically reduced and such LCD televisions obtained same price levels as the former 28" (71 cm) CRT based categories.

Monochrome LEDs: such as red, green, yellow or blue LEDs are used in the small passive monochrome LCDs typically used in clocks, watches and small appliances.

Today, most LCD screens are being designed with an LED backlight instead of the traditional CCFL backlight, while that backlight is dynamically controlled with the video information (dynamic backlight control). The combination with the dynamic backlight control, invented by Philips researchers Douglas Stanton, Martinus Stroomer and Adrianus de Vaan, simultaneously increases the dynamic range of the display system (also marketed as HDR, high dynamic range television or FLAD, full-area local area dimming).

The LCD backlight systems are made highly efficient by applying optical films such as prismatic structure (prism sheet) to gain the light into the desired viewer directions and reflective polarizing films that recycle the polarized light that was formerly absorbed by the first polarizer of the LCD (invented by Philips researchers Adrianus de Vaan and Paulus Schaareman),

A pink elastomeric connector mating an LCD panel to circuit board traces, shown next to a centimeter-scale ruler. The conductive and insulating layers in the black stripe are very small.

A standard television receiver screen, a modern LCD panel, has over six million pixels, and they are all individually powered by a wire network embedded in the screen. The fine wires, or pathways, form a grid with vertical wires across the whole screen on one side of the screen and horizontal wires across the whole screen on the other side of the screen. To this grid each pixel has a positive connection on one side and a negative connection on the other side. So the total amount of wires needed for a 1080p display is 3 x 1920 going vertically and 1080 going horizontally for a total of 6840 wires horizontally and vertically. That"s three for red, green and blue and 1920 columns of pixels for each color for a total of 5760 wires going vertically and 1080 rows of wires going horizontally. For a panel that is 28.8 inches (73 centimeters) wide, that means a wire density of 200 wires per inch along the horizontal edge.

The LCD panel is powered by LCD drivers that are carefully matched up with the edge of the LCD panel at the factory level. The drivers may be installed using several methods, the most common of which are COG (Chip-On-Glass) and TAB (Tape-automated bonding) These same principles apply also for smartphone screens that are much smaller than TV screens.anisotropic conductive film or, for lower densities, elastomeric connectors.

Monochrome and later color passive-matrix LCDs were standard in most early laptops (although a few used plasma displaysGame Boyactive-matrix became standard on all laptops. The commercially unsuccessful Macintosh Portable (released in 1989) was one of the first to use an active-matrix display (though still monochrome). Passive-matrix LCDs are still used in the 2010s for applications less demanding than laptop computers and TVs, such as inexpensive calculators. In particular, these are used on portable devices where less information content needs to be displayed, lowest power consumption (no backlight) and low cost are desired or readability in direct sunlight is needed.

A comparison between a blank passive-matrix display (top) and a blank active-matrix display (bottom). A passive-matrix display can be identified when the blank background is more grey in appearance than the crisper active-matrix display, fog appears on all edges of the screen, and while pictures appear to be fading on the screen.

STN LCDs have to be continuously refreshed by alternating pulsed voltages of one polarity during one frame and pulses of opposite polarity during the next frame. Individual pixels are addressed by the corresponding row and column circuits. This type of display is called response times and poor contrast are typical of passive-matrix addressed LCDs with too many pixels and driven according to the "Alt & Pleshko" drive scheme. Welzen and de Vaan also invented a non RMS drive scheme enabling to drive STN displays with video rates and enabling to show smooth moving video images on an STN display.

Bistable LCDs do not require continuous refreshing. Rewriting is only required for picture information changes. In 1984 HA van Sprang and AJSM de Vaan invented an STN type display that could be operated in a bistable mode, enabling extremely high resolution images up to 4000 lines or more using only low voltages.

High-resolution color displays, such as modern LCD computer monitors and televisions, use an active-matrix structure. A matrix of thin-film transistors (TFTs) is added to the electrodes in contact with the LC layer. Each pixel has its own dedicated transistor, allowing each column line to access one pixel. When a row line is selected, all of the column lines are connected to a row of pixels and voltages corresponding to the picture information are driven onto all of the column lines. The row line is then deactivated and the next row line is selected. All of the row lines are selected in sequence during a refresh operation. Active-matrix addressed displays look brighter and sharper than passive-matrix addressed displays of the same size, and generally have quicker response times, producing much better images. Sharp produces bistable reflective LCDs with a 1-bit SRAM cell per pixel that only requires small amounts of power to maintain an image.

Segment LCDs can also have color by using Field Sequential Color (FSC LCD). This kind of displays have a high speed passive segment LCD panel with an RGB backlight. The backlight quickly changes color, making it appear white to the naked eye. The LCD panel is synchronized with the backlight. For example, to make a segment appear red, the segment is only turned ON when the backlight is red, and to make a segment appear magenta, the segment is turned ON when the backlight is blue, and it continues to be ON while the backlight becomes red, and it turns OFF when the backlight becomes green. To make a segment appear black, the segment is always turned ON. An FSC LCD divides a color image into 3 images (one Red, one Green and one Blue) and it displays them in order. Due to persistence of vision, the 3 monochromatic images appear as one color image. An FSC LCD needs an LCD panel with a refresh rate of 180 Hz, and the response time is reduced to just 5 milliseconds when compared with normal STN LCD panels which have a response time of 16 milliseconds.

Samsung introduced UFB (Ultra Fine & Bright) displays back in 2002, utilized the super-birefringent effect. It has the luminance, color gamut, and most of the contrast of a TFT-LCD, but only consumes as much power as an STN display, according to Samsung. It was being used in a variety of Samsung cellular-telephone models produced until late 2006, when Samsung stopped producing UFB displays. UFB displays were also used in certain models of LG mobile phones.

In-plane switching is an LCD technology that aligns the liquid crystals in a plane parallel to the glass substrates. In this method, the electrical field is applied through opposite electrodes on the same glass substrate, so that the liquid crystals can be reoriented (switched) essentially in the same plane, although fringe fields inhibit a homogeneous reorientation. This requires two transistors for each pixel instead of the single transistor needed for a standard thin-film transistor (TFT) display. The IPS technology is used in everything from televisions, computer monitors, and even wearable devices, especially almost all LCD smartphone panels are IPS/FFS mode. IPS displays belong to the LCD panel family screen types. The other two types are VA and TN. Before LG Enhanced IPS was introduced in 2001 by Hitachi as 17" monitor in Market, the additional transistors resulted in blocking more transmission area, thus requiring a brighter backlight and consuming more power, making this type of display less desirable for notebook computers. Panasonic Himeji G8.5 was using an enhanced version of IPS, also LGD in Korea, then currently the world biggest LCD panel manufacture BOE in China is also IPS/FFS mode TV panel.

In 2011, LG claimed the smartphone LG Optimus Black (IPS LCD (LCD NOVA)) has the brightness up to 700 nits, while the competitor has only IPS LCD with 518 nits and double an active-matrix OLED (AMOLED) display with 305 nits. LG also claimed the NOVA display to be 50 percent more efficient than regular LCDs and to consume only 50 percent of the power of AMOLED displays when producing white on screen.

This pixel-layout is found in S-IPS LCDs. A chevron shape is used to widen the viewing cone (range of viewing directions with good contrast and low color shift).

Vertical-alignment displays are a form of LCDs in which the liquid crystals naturally align vertically to the glass substrates. When no voltage is applied, the liquid crystals remain perpendicular to the substrate, creating a black display between crossed polarizers. When voltage is applied, the liquid crystals shift to a tilted position, allowing light to pass through and create a gray-scale display depending on the amount of tilt generated by the electric field. It has a deeper-black background, a higher contrast ratio, a wider viewing angle, and better image quality at extreme temperatures than traditional twisted-nematic displays.

Blue phase mode LCDs have been shown as engineering samples early in 2008, but they are not in mass-production. The physics of blue phase mode LCDs suggest that very short switching times (≈1 ms) can be achieved, so time sequential color control can possibly be realized and expensive color filters would be obsolete.

Some LCD panels have defective transistors, causing permanently lit or unlit pixels which are commonly referred to as stuck pixels or dead pixels respectively. Unlike integrated circuits (ICs), LCD panels with a few defective transistors are usually still usable. Manufacturers" policies for the acceptable number of defective pixels vary greatly. At one point, Samsung held a zero-tolerance policy for LCD monitors sold in Korea.ISO 13406-2 standard.

Dead pixel policies are often hotly debated between manufacturers and customers. To regulate the acceptability of defects and to protect the end user, ISO released the ISO 13406-2 standard,ISO 9241, specifically ISO-9241-302, 303, 305, 307:2008 pixel defects. However, not every LCD manufacturer conforms to the ISO standard and the ISO standard is quite often interpreted in different ways. LCD panels are more likely to have defects than most ICs due to their larger size. For example, a 300 mm SVGA LCD has 8 defects and a 150 mm wafer has only 3 defects. However, 134 of the 137 dies on the wafer will be acceptable, whereas rejection of the whole LCD panel would be a 0% yield. In recent years, quality control has been improved. An SVGA LCD panel with 4 defective pixels is usually considered defective and customers can request an exchange for a new one.

Some manufacturers, notably in South Korea where some of the largest LCD panel manufacturers, such as LG, are located, now have a zero-defective-pixel guarantee, which is an extra screening process which can then determine "A"- and "B"-grade panels.clouding (or less commonly mura), which describes the uneven patches of changes in luminance. It is most visible in dark or black areas of displayed scenes.

The zenithal bistable device (ZBD), developed by Qinetiq (formerly DERA), can retain an image without power. The crystals may exist in one of two stable orientations ("black" and "white") and power is only required to change the image. ZBD Displays is a spin-off company from QinetiQ who manufactured both grayscale and color ZBD devices. Kent Displays has also developed a "no-power" display that uses polymer stabilized cholesteric liquid crystal (ChLCD). In 2009 Kent demonstrated the use of a ChLCD to cover the entire surface of a mobile phone, allowing it to change colors, and keep that color even when power is removed.

In 2004, researchers at the University of Oxford demonstrated two new types of zero-power bistable LCDs based on Zenithal bistable techniques.e.g., BiNem technology, are based mainly on the surface properties and need specific weak anchoring materials.

Resolution The resolution of an LCD is expressed by the number of columns and rows of pixels (e.g., 1024×768). Each pixel is usually composed 3 sub-pixels, a red, a green, and a blue one. This had been one of the few features of LCD performance that remained uniform among different designs. However, there are newer designs that share sub-pixels among pixels and add Quattron which attempt to efficiently increase the perceived resolution of a display without increasing the actual resolution, to mixed results.

Spatial performance: For a computer monitor or some other display that is being viewed from a very close distance, resolution is often expressed in terms of dot pitch or pixels per inch, which is consistent with the printing industry. Display density varies per application, with televisions generally having a low density for long-distance viewing and portable devices having a high density for close-range detail. The Viewing Angle of an LCD may be important depending on the display and its usage, the limitations of certain display technologies mean the display only displays accurately at certain angles.

Temporal performance: the temporal resolution of an LCD is how well it can display changing images, or the accuracy and the number of times per second the display draws the data it is being given. LCD pixels do not flash on/off between frames, so LCD monitors exhibit no refresh-induced flicker no matter how low the refresh rate.

Color performance: There are multiple terms to describe different aspects of color performance of a display. Color gamut is the range of colors that can be displayed, and color depth, which is the fineness with which the color range is divided. Color gamut is a relatively straight forward feature, but it is rarely discussed in marketing materials except at the professional level. Having a color range that exceeds the content being shown on the screen has no benefits, so displays are only made to perform within or below the range of a certain specification.white point and gamma correction, which describe what color white is and how the other colors are displayed relative to white.

Brightness and contrast ratio: Contrast ratio is the ratio of the brightness of a full-on pixel to a full-off pixel. The LCD itself is only a light valve and does not generate light; the light comes from a backlight that is either fluorescent or a set of LEDs. Brightness is usually stated as the maximum light output of the LCD, which can vary greatly based on the transparency of the LCD and the brightness of the backlight. Brighter backlight allows stronger contrast and higher dynamic range (HDR displays are graded in peak luminance), but there is always a trade-off between brightness and power consumption.

Usually no refresh-rate flicker, because the LCD pixels hold their state between refreshes (which are usually done at 200 Hz or faster, regardless of the input refresh rate).

No theoretical resolution limit. When multiple LCD panels are used together to create a single canvas, each additional panel increases the total resolution of the display, which is commonly called stacked resolution.

LCDs can be made transparent and flexible, but they cannot emit light without a backlight like OLED and microLED, which are other technologies that can also be made flexible and transparent.

As an inherently digital device, the LCD can natively display digital data from a DVI or HDMI connection without requiring conversion to analog. Some LCD panels have native fiber optic inputs in addition to DVI and HDMI.

Limited viewing angle in some older or cheaper monitors, causing color, saturation, contrast and brightness to vary with user position, even within the intended viewing angle. Special films can be used to increase the viewing angles of LCDs.

As of 2012, most implementations of LCD backlighting use pulse-width modulation (PWM) to dim the display,CRT monitor at 85 Hz refresh rate would (this is because the entire screen is strobing on and off rather than a CRT"s phosphor sustained dot which continually scans across the display, leaving some part of the display always lit), causing severe eye-strain for some people.LED-backlit monitors, because the LEDs switch on and off faster than a CCFL lamp.

Only one native resolution. Displaying any other resolution either requires a video scaler, causing blurriness and jagged edges, or running the display at native resolution using 1:1 pixel mapping, causing the image either not to fill the screen (letterboxed display), or to run off the lower or right edges of the screen.

Fixed bit depth (also called color depth). Many cheaper LCDs are only able to display 262144 (218) colors. 8-bit S-IPS panels can display 16 million (224) colors and have significantly better black level, but are expensive and have slower response time.

Input lag, because the LCD"s A/D converter waits for each frame to be completely been output before drawing it to the LCD panel. Many LCD monitors do post-processing before displaying the image in an attempt to compensate for poor color fidelity, which adds an additional lag. Further, a video scaler must be used when displaying non-native resolutions, which adds yet more time lag. Scaling and post processing are usually done in a single chip on modern monitors, but each function that chip performs adds some delay. Some displays have a video gaming mode which disables all or most processing to reduce perceivable input lag.

Dead or stuck pixels may occur during manufacturing or after a period of use. A stuck pixel will glow with color even on an all-black screen, while a dead one will always remain black.

In a constant-on situation, thermalization may occur in case of bad thermal management, in which part of the screen has overheated and looks discolored compared to the rest of the screen.

Loss of brightness and much slower response times in low temperature environments. In sub-zero environments, LCD screens may cease to function without the use of supplemental heating.

The production of LCD screens uses nitrogen trifluoride (NF3) as an etching fluid during the production of the thin-film components. NF3 is a potent greenhouse gas, and its relatively long half-life may make it a potentially harmful contributor to global warming. A report in Geophysical Research Letters suggested that its effects were theoretically much greater than better-known sources of greenhouse gasses like carbon dioxide. As NF3 was not in widespread use at the time, it was not made part of the Kyoto Protocols and has been deemed "the missing greenhouse gas".

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Abbreviated LCD, liquid crystal display is a flat, thin display device that has replaced the older CRT display. LCD provides better picture quality and support for large resolutions.

Generally, LCD refers to a type of monitor utilizing the LCD technology, but also flat-screen displays like those in laptops, calculators, digital cameras, digital watches, and other similar devices.

There"s also an FTP command that uses the letters "LCD." If that"s what you"re after, you can read more about it on Microsoft"s website, but it doesn"t have anything to do with computers or TV displays.

As liquid crystal display would indicate, LCD screens use liquid crystals to switch pixels on and off to reveal a specific color. Liquid crystals are like a mixture between a solid and a liquid, where an electric current can be applied to change their state in order for a specific reaction to occur.

These liquid crystals can be thought of like a window shutter. When the shutter is open, light can easily pass through into the room. With LCD screens, when the crystals are aligned in a special way, they no longer allow that light through.

It"s the back of an LCD screen that"s responsible for shining light through the screen. In front of the light is a screen made up of pixels that are colored red, blue, or green. The liquid crystals are responsible for electronically turning a filter on or off in order to reveal a certain color to or keep that pixel black.

This means that LCD screens work by blocking light emanating from the back of the screen instead of creating the light themselves like how CRT screens work. This allows LCD monitors and TVs to use much less power than CRT ones.

LED stands for light-emitting diode. Although it has a different name than liquid crystal display, it"s not something entirely different, but really just a different type of LCD screen.

The major difference between LCD and LED screens is how they provide backlighting. Backlighting refers to how the screen turns light on or off, something that"s crucial for providing a great picture, especially between black and colored portions of the screen.

A regular LCD screen uses a cold cathode fluorescent lamp (CCFL) for backlighting purposes, while LED screens use more efficient and smaller light-emitting diodes (LED"s). The difference is that CCFL-backlit LCDs can"t always block out all black colors, in which case something like a black on white scene in a movie may not appear so black after all, while LED-backlit LCDs can localize the blackness for a much deeper contrast.

If you"re having a hard time understanding this, just consider a dark movie scene as an example. In the scene is a really dark, black room with a closed door that"s allowing some light through the bottom crack. An LCD screen with LED backlighting can pull it off better than CCFL backlighting screens because the former can turn on color for just the portion around the door, allowing all the rest of the screen to remain truly black.

Not every LED display is capable of dimming the screen locally, like you just read. It"s usually full-array TV"s (versus edge-lit ones) that support local dimming.

Unlike CRT monitors and TVs, LCD screens don"t have a refresh rate. You might need to change the monitor"s refresh rate setting on your CRT screen if eye strain is a problem, but it"s not needed on the newer LCD screens.

Most LCD computer monitors have a connection for HDMI and DVI cables. Some still support VGA cables, but that"s much less common. If your computer"s video card only supports the older VGA connection, double-check that the LCD monitor has a connection for it. You might need to purchase a VGA to HDMI or VGA to DVI adapter so that both ends can be used on each device.

CRT hardware, LCD"s predecessor, was famously susceptible to screen burn-in, a faint image imprinted on the electronic display that could not be removed.

LCD conditioning solves minor problems that occur on LCD monitors, including persistent images or ghost images. The process involves flooding the screen or monitor with various colors (or with all white). Dell includes an image conditioning feature in its LCD monitors.

If you see a black spot that never changes, it"s likely a dead pixel and may require a professional repair or screen replacement. Stuck pixels are usually red, green, blue, or yellow (although they can be black in rare cases). A dead-pixel testdistinguishes between stuck and dead pixels.

A liquid crystal display (LCD) monitor is a computer monitor or display that uses LCD technology to show clear images, and is found mostly in laptop computers and flat panel monitors. This technology has replaced the traditional cathode ray tube (CRT) monitors, which were the previous standard and once were considered to have better picture quality than early LCD variants. With the introduction of better LCD technology and its continuous improvement, LCD is now the clear leader over CRT, in terms of color and picture quality, not to mention capabilities for large resolutions. Also, LCD monitors may be made much more cheaply than CRT monitors.

A liquid crystal display (LCD) has liquid crystal material sandwiched between two sheets of glass. Without any voltage applied between transparent electrodes, liquid crystal molecules are aligned in parallel with the glass surface. When voltage is applied, they change their direction and they turn vertical to the glass surface. They vary in optical characteristics, depending on their orientation. Therefore, the quantity of light transmission can be controlled by combining the motion of liquid crystal molecules and the direction of polarization of two polarizing plates attached to the both outer sides of the glass sheets. LCDs utilize these characteristics to display images.

An LCD consists of many pixels. A pixel consists of three sub-pixels (Red/Green/Blue, RGB). In the case of Full-HD resolution, which is widely used for smartphones, there are more than six million (1,080 x 1,920 x 3 = 6,220,800) sub-pixels. To activate these millions of sub-pixels a TFT is required in each sub-pixel. TFT is an abbreviation for "Thin Film Transistor". A TFT is a kind of semiconductor device. It serves as a control valve to provide an appropriate voltage onto liquid crystals for individual sub-pixels. A TFT LCD has a liquid crystal layer between a glass substrate formed with TFTs and transparent pixel electrodes and another glass substrate with a color filter (RGB) and transparent counter electrodes. In addition, polarizers are placed on the outer side of each glass substrate and a backlight source on the back side. A change in voltage applied to liquid crystals changes the transmittance of the panel including the two polarizing plates, and thus changes the quantity of light that passes from the backlight to the front surface of the display. This principle allows the TFT LCD to produce full-color images.

Photo: Prove to yourself that an LCD display uses polarized light. Simply put on a pair of polarizing sunglasses and rotate your head (or the display). You"ll see the display at its brightest at one angle and at its darkest at exactly 90 degrees to that angle.

Looking to buy a new TV, smartphone, monitor or any other type of product that has a display? It’s likely you’ve come across the term LCD in some form or fashion.

LCD stands for ‘liquid crystal display’, a reference to the liquid crystal material used in the display to strategically block out light. It’s a display type commonly used across a range of TVs, monitors, tablet and phone screens.

This light becomes the light source for the hundreds or thousands of RGB (Red, Green, Blue) pixels packed into the display, the combination of which creates the image seen on-screen.

Other concerns to consider the number of pixels in a display, along with what type of LCD the screen uses. For example, IPS LCD displays offer better contrast ratios and viewing angles than TN LCD displays.

Like LCD displays, LED uses liquid crystal technology to control where light can and cannot go. The distinction between the two was originally made because LCD screens used CCFL (cold cathode fluorescent lamps) as their light source, which were larger and less efficient than those found in LED TVs.

Over the last few years, LCD displays have found themselves gradually replaced by OLED from TVs to flagship phones such as the Galaxy S22 and iPhone 13 to the Nintendo Switch OLED.

Unlike LCD screens, OLED (organic light-emitting diode) displays don’t require a backlight. Rather OLED screens can switch individual pixels on for deeper blacks and more intense contrast. The lack of a backlight also means the screen is thinner, leading to slimmer designs and reduced power consumption when compared with the older display type.

However, OLED generally costs much more to produce and can suffer from issues like image retention and burn-in if the screen is left displaying a static image for too long, although screensavers and reducing the brightness of the screen can manage these issues.

• Perform highly diversified duties to install and maintain electrical apparatus on production machines and any other facility equipment (Screen Print, Punch Press, Steel Rule Die, Automated Machines, Turret, Laser Cutting Machines, etc.).

LCD display screens are everywhere. You probably own one or more devices with an LCD display screen at home and at work. This includes your TV, computer monitor, watches, clocks, smartphones, and even calculators.

But have you ever wondered about how your LCD display screen works, its lifespan, components, and how it holds up to other emerging display technologies today?

Knowing all these things about your LCD display lets you appreciate your screen all the more. Caring for your device becomes easier when you’re armed with this knowledge.

LCD display screens make use of Liquid Crystal Display technology. The screen is embedded with liquid crystals, a substance that has properties in between a conventional liquid and a solid crystal. Liquid crystals can flow, but their molecules carry a crystal-like solid orientation.

Liquid crystals are responsible for producing an image flashed onto the LCD screen. They don’t emit light, though. Backlights are used to illuminate these crystals.

A display screen is made up of several tiny color blocks called pixels. The term is a portmanteau of “picture” and “element”, denoting pixels as little elements making up an entire screen picture. A screen is typically made up of millions of pixels.

Every pixel on the display screen is made up of red, blue, and green light. These lights can be quickly turned on or off to create an overall moving picture or image.

Now, in LCD displays, pixels are regulated by using liquid crystals for rotating polarized light. Polarized light denotes light waves with vibrations occurring in a single plane. In LCDs, this is achieved by using polarized layers.

A single LCD contains millions of pixels, nematic liquid crystals, polarizing filters, and transistors. They all work together to create images on the screen.

Most LCD monitors have a lifespan ranging from 30,000 to 60,000 hours. That’s equivalent to 5-7 years using the monitor for 24 hours per day. It could also translate to 10-20 years with running the monitor for 8 hours a day, 5 days a week.

The backlight’s life expectancy is the biggest factor in determining the LCD display lifespan. It’s because liquid crystals do not give off light from themselves. The liquid crystals depend on the backlight for illuminating them. Hence, the LCD screen wears off when the backlights dim as it reaches its maximum lifespan.

The backlight serves as the illuminator of the entire LCD display device. Without a backlight, the LCD device remains darkened and hard to use. Backlights are installed directly behind the LCD panel to lighten up the display.

Simple devices such as pocket calculators don’t use a backlight for their LCD screens. Users rely on natural light to see the numbers displayed on such calculators. However, the majority of modern LCD screens such as televisions, computer monitors, smartphones, aviation screen panels, outdoor signages, and medical monitoring devices use backlights as their internal light source.

This type of backlight is the most popular and widely-used light source for LCDs today. Light-emitting diodes are semiconductors that emit light once electric current flows into it. Particles carrying the electric current are called electrons holes. These combine with electrons in the semiconductor, releasing photons (light particles).

Edge-Lit White LED (EL-WLED)– One or more LED rows are placed on the screen’s edge. A special light diffuser is used to scatter the light evenly across the entire display screen. Computer monitors, laptops, notebooks, and even HDTVs are now lit in this way.

White LED (WLED)– The LCD panel’s rear side is lit up with several white-colored LEDs. A diffuser is set in front of the LEDs to help evenly smooth out the light throughout the screen. Some computer monitors and large-screen LCD TVs use this LED technology.

ELP uses electroluminescent materials such as colored phosphors instead of heat to create light. This material is placed in between two conductor layers. The material emits light as a result of an electric current flowing through it. ELPs are mostly used in small LCD screens.

CCFL backlight uses a cold cathode fluorescent lamp as its main light source. This lamp consists of a cathode that isn’t heated electrically by a filament, hence the connotation “cold”.  A diffuser is placed in front of the CCFL lamp to evenly distribute light across the entire screen.

Computer monitors and TV screens predominantly used CCFLs for backlights. However, modern manufacturers opt for LED technology instead of CCFL for their devices’ backlights.

HCFL backlights have filaments that need to be heated to excite mercury atoms, cause the current to flow, and ultimately emit light. HCFLs are often used in LCD equipment such as medical devices, custom task-oriented lamps, scanners, and outdoor LCD signs.

Liquid crystals are the heart of an LCD display. This unique substance flows like a liquid but retains many characteristics of solid crystals. They have long and cylindrical-shaped molecules that can twist when changes in molecular orientation happen.

Different liquid crystal families are used in LCD displays. One requirement of such liquids is to exhibit mutual attraction. Also, the molecules in the liquid crystal need to be anisotropic. This means that the liquid crystal molecules have that average structural order along a molecular axis.

The nematic phase is characterized by the crystal molecules freely moving around the liquid. However, these molecules point themselves to one direction only, making it unique from pure liquid molecules. Nematic liquid crystals are the most common liquid used in LCD screens.

Now, molecules in liquid crystals move as a reaction to an electric field. Their arrangement changes as a voltage are applied to them. This allows liquid crystals to control polarized light, which, in turn, defines which pixels on a screen will be illuminated or not.

Color filters are found in between the liquid crystals. These filters determine whether the pixel shows red, green, or blue colors when activated. The filters work by independently controlling the pixel’s red, green, and blue sub-pixels. With this, the LCD screen can reproduce all possible colors found in the color space.

An LCD cell is made up of two polarizing filters. They enclose the LCD display and color filters. One polarizing filter is located in front of the backlight and is horizontal in orientation. The other one is found just beneath the pixel in front and is vertical in orientation. Polarizing filters are typically made of transparent crystals or glass substrates.

The role of polarizing filters is to control which light patterns can pass through the LCD screen. Without these filters, visual images generated by the LCD panel will have a poor contrast ratio and an inferior quality image.

Now, light emitted by your panel’s backlight source enters the first horizontal polarizing filter. It then passes through the liquid crystals. The polarized light vibrates vertically if the liquid crystals are in a twisted state. Hence, these light waves can then pass through the second vertical polarizing filter. The pixel on the screen turns on and is illuminated properly.

Meanwhile, if the LCD display is arranged in a straightened way, the horizontal light waves that came from the first polarizing filter will be blocked from entering the vertical polarizing filter. The pixel is then turned off and no light illuminates it.

The two polarizing filters need to be vertical and horizontal in orientation, respectively. If the filters are oriented in the same way (ie; both horizontal or both vertical) will block all the light passing through, displaying nothing on the screen.

TFTs are responsible for providing electrical voltage to the LCD display. Each screen pixel has a corresponding transistor, enabling the pixels to easily be controlled in unison through changes in electrical current.

Using TFTs requires less charge and less power to operate the LCD display screen successfully. TFT use also leads to sharper images because each pixel has its own transistor controlling it. The charge given to a certain pixel can be actively maintained even if the screen is refreshed to display another image.

That’s all the basic information you need to know about LCD display screens. Now, you know how an LCD screen works, its possible lifespan, its components, and how it compares to other display technologies.

Armed with this information, you can better appreciate and take care of your LCD display devices. And in case you’re planning to add display devices to your business, the information you’ve learned will help you make educated choices regarding the display technologies you’ll utilize.

M2 PRESSWIRE-August 29, 2019-: TFT LCD Display Modules Market To Show Extensive Growth Due To The Increasing Popularity Of LCD Displays Till 2023 | Million Insights

Kaohsiung Opto-Electronics (KOE), a wholly owned subsidiary of Japan Display Inc (JDI), was formed in 2012 to advance the design, development and manufacture of market leading TFT LCD display modules previously established by Hitachi.

However, the R&D team of the Chinese firm has developed an algorithm-based approach which uses deep learning and neural networks to optimise and recognise fingerprints on a LCD display. The breakthrough could result in a big development in the prominence of in-display fingerprint sensors on smartphones.

Greensburg, PA, March 02, 2019 --(PR.com)-- AGDisplays, an advanced LCD display solutions company, announces the release of a new line of powerful IPS LCD modules for use in Marine electronic applications.

LCD Display Technology to Represent Robust Growth Compared to TFT-LCD technology, LCD display technology is anticipated to witness strong growth in the global automotive smart display market.

NEC Display Solutions of America, Inc., a provider of commercial LCD display and projector solutions, is pleased to announce that Richard Ventura, Vice President of Strategy, NEC Display Solutions of America, has been selected as a 2018 inductee to System Contract News" Hall of Fame, the company said.

(http://www.ibtimes.com/apple-reportedly-going-big-6-inch-lcd-iphone-8-successor-2593796) IBT previously reported that that Apple is planning to put a 6-inch LCD display on the iPhone 8 successor and Japan Display would be supplying those LCD panels.

One 5.5-inch version will have an LCD display, while a premium version will pack an OLED display for the first time in the iPhone"s history, according to the supply chain analyst (via Apple Insider).

- Japanese IT company NEC"s NEC Display Solutions of America commercial LCD display and projector solutions unit has launched the MultiSync MDC212C2 monitor, a clinical review display with a built-in calibration timer so technicians can schedule calibrations of displays during off hours, the company said.

Tokyo, Oct 7, 2014 - (JCN Newswire) - Sharp"s "8K full-spec LCD display" exhibited at CEATEC Japan, a comprehensive annual exhibition showcasing the latest in IT and electronics from October 7 to 11, has received "Minister of Internal Affairs and Communications Award of CEATEC AWARD 2014".

Leaked photos of a gadget claimed to be the next Apple iPad appear to show a bonded LCD display, which would allow either a thinner next-gen model or a larger battery, according to a report from UK-based tech site The Register.

"The new Micro820 controller, LCD display, plug-in modules and Connected Components Workbench software Release 6.0 have the features and options that help them differentiate their offerings and be more competitive." Connected Components Workbench software simplifies the configuration, design and maintenance of the Micro820 controller.