dark lcd screen problem manufacturer

Black screens appear in the daily work of industrial LCD screens, what should we do? Don’t worry. black screen fault treatment method. Today, we summarize the reasons for the black screen fault treatment method by the failure of industrial LCD screens:

In addition, it is important to check the quality of the power switch and reset key and the correct connection between them and the motherboard, because the power switch and reset key in many inferior cases are often damaged after several times of use, resulting in a black screen display. If the power supply is damaged, replace it.

When the Industrial LCD display is powered up, there is a click sound, and the LCD’s power indicator lights up. When users move to the LCD screen, there is a hissing sound, and hairs on the back of their hands stand up.

If the Industrial LCD screen and speakers within the host let out a long and a short hum industrial LCD screen indicates display card and the connection between the mainboard has a problem, or display card and display this connection has a problem, can be the key to check whether the slot contacts good whether there is a foreign body inside the tank, the display card in a motherboard slot for testing, to determine whether there is something wrong with the slot.

Beijing STONE Technology Co., Ltd. focuses on the industrial display screen, Industrial touch screen product development, and manufacturing, products are widely used in medical equipment, industrial equipment, civil fields, and smart home.

Liquid crystal displays (LCDs) are the most widely used display technology. Their applications cover TV, mobile phone, appliances, automotive, smart home, industrial meters, consumer electronics, POS, marine, aerospace, military etc. LCD screen display problem can occur for several reasons.

Effect of environmental conditions on the LCD assembly. Environmental conditions include both the effects of temperature and humidity, and cyclic loading.

Effect of manufacturing process. With the development of LCD for more than 40 years and the modern manufacturing equipment, this kind if defects are getting rear.

Common failures seen in LCDs are a decrease in screen contrast, non-functioning pixels or the whole display, and broken glass. Different kinds of LCD display problem need to have different kinds of fix methods or make the decision not worthwhile to repair.

Broken glassIf you accidently drop the LCD and you find it broken on the surface but the display still works. You might just break the touch panel; you can find a repair house or find a youtube video to replace the touch panel. If you find the display not showing, especially you find the fluid leaking out. You need to reply the whole display modules.

Dim LCD displayLCD can’t emit light itself. It uses backlight. Normally, the backlight is not fully driven, you can increase the LED backlight to make a dim LCD display brighter. But if you LCD display has been used for a long time, it is possible that the LED backlight has to be the end of life (not brightness enough) if you turn on 100% backlight brightness. In that case to fix LCD screen, you have to find a way to change the backlight. For some display, it is an easy job but it can be difficult for other displays depending on the manufacturing process.

Image sticking (Ghosting)Sometimes, you will find the previous image still appearing at the background even if you change to another image. It is also called burn in. This kind of failure doesn’t need to repair by professionals. You can simply shut off the display overnight, this kind of problem will go away. Please do remember that displaying a static image for a long time should be avoided.

LCD has white screen – If a LCD has a white screen which means the backlight is good. Simply check your signal input sources which are the most causes. It can also be caused by the display totally damaged by ESD or excess heat, shock which make the LCD controller broken or the connection failure which has to be repaired by professionals.

Blur ImagesAs the LCD images are made of RGB pixels, the screen shouldn’t be blur like old CRT displays. If you do see blur images, they might be caused by two reasons. 1) LCD has certain response time, if you are playing games or watch fast action movies, some old LCD displays can have image delays. 2) The surface of the LCD is made of a layer of plastic film with maximum hardness of 3H. If you clean the surface often or use the wrong detergent or solvent which cause the surface damage. To fix damage on LED screen it’s need to be changed with professionals.

A black screen on an Android can be frustrating. If you can tell your Android phone is on, but the screen is black and won"t respond, there are a few things you can do that might get it working again.

Wait until the batteries die completely and the phone shuts down and then recharge the phone, and restart it after it"s fully charged. If there is a critical system error causing the black screen, this should get your phone working again.

Gently, but firmly press your phone from both sides, squeezing the front and back together. If there"s a loose LCD connection, this could help reseat the connection and get the screen working again. If this works, consider taking the phone to an authorized service center to have them firmly reseat the LCD cable.

If your phone is in a case, remove it from the case before you start this process so that you can accurately gauge how much pressure to put on your phone without breaking the screen.

Plug in phone, wait five minutes, and then try to do a Force Restart. This ensure the phone has enough power to restart, and restarting could clear any errors that might be affecting the screen.

If you have one, remove the stylus and see if it causes the screen to come on. If it does, navigate to Settings > General management > Reset and then choose Auto Restart and schedule a time for your phone to restart. You"ll have to wait until this time to see if an automatic restart fixes your problem.

Alternatively, you could also choose Factory data reset from the screen to completely reset your phone back to factory specs. This can be useful if you"ve installed a corrupt app that is affecting your display.

Reboot your phone into Safe mode. Safe mode may allow you to navigate the phone to restart it, clear the cache (more on that below), or perform other tasks that could help fix the black screen problem.

Tim, sounds to me like the backlight inverter is going out. You want to definitely check on fuses or continuity of voltage supply lines going to the X Board/s, (your case check the X Board) as well as the LVDS cable. Replace blown fuses, connect broken lines, and resolder loose solders. Check on the capacitors on your boards, they may be either loose or popped. Look for any leakage on the boards (looks like a oily sticky substance) and check the top of the capacitors. they should be flat. Any bulging indicates a failed capacitor, The older LG"s have the backlight inverter power separate from the power supply, and in that case you will require a new LCD Panel. Very costly, if you can even find somebody who has them for sale. The newer LG"s have the inverter connected to the power board. In that case you could try to fix it by replacing the power board. It would be great if besides the model number you could find the Chassis number. It might be possible to get a service manual for you and give you some more specific details for your TV. Hope this gets you started in the right direction. Good Luck.

Hi. It looks like the backlight on your LED TV has failed. LED TVs feature long thin circuit boards with surface-mount LEDs packaged every few inches. Direct backlit TVs have quite a few strips with the LEDS spaced out over the area of the LCD panel. Edge lit LED Tvs have the majority of the LEDs on the sides of the LCD panel. It looks like your TV is direct LED backlight.

The reason why Vizio told you to buy a new TV is because the LEDs which have failed are the hardest part to get to inside the TV. It requires you to disassemble the lcd display assembly, which is very fragile. In order to disassembly the display assembly, you need a lot of space and a lot of patience.

Also, even if you replace the LEDs or LED strips, it is extremely likely that your backlight will fail again within 2 years. A lot of the folks who repair LED TVs mention to go into the settings of your tv and manually turn the backlight of the LCD at least half way down. Lowering the backlight brightness will increase the lifespan of your backlight.

One of the most concerning issues to plague smartphone users is a black screen, often referred to as the “black screen of death.” However, despite the harsh name, this issue can be remedied in several ways.

To fix a black screen on an iPhone or Android, the first (and easiest) step is to do a hard reset. This basically entails rebooting the phone’s software. A hard reset can be performed right on your phone, although the process differs depending on what type of device you own.

If you’re still staring at a blank screen, it’s possible that the cable connecting the logic board to the LCD screen has become disconnected. This can occur if you accidentally drop your phone a few times. In order to regain your screen’s functionality, the cable will need to be plugged back in.

If you want to repair a broken iPhone or Android this way, it’s best to seek help from a professional. While you may find DIY instructions online, you could risk causing irreparable damage to your device if you don’t know what you’re doing. So, if you suspect that your phone’s LCD cable is disconnected, search for a place in Las Vegas that fixes phones.

When your phone screen goes black randomly, it may be an indication that something is wrong with your operating system. In that case, a factory reset is often beneficial. During a factory reset, your device’s data and settings are completely wiped, returning the phone to its original state (i.e., the state it was in when you first purchased it).

If you’re in need of smartphone repair, NerdsToGo can help. Our expert team understands the inner workings of a wide variety of devices. We’ll determine the root of the problem to get your phone up and running again as quickly as possible. And, if you don’t have time to visit our storefront for your smartphone repairs, we’ll come to you!

LED-backlit LCD TVs typically come in one of two sub-types of panels: Vertical Alignment (VA) or In-Plane Switching (IPS). VA panels tend to have much high contrast ratios, and therefore better black uniformity. IPS panels, on the other hand, have worse contrast ratios and suffer from more backlight issues that can affect black uniformity, including "IPS glow", which is a kind of "glow" effect that can be seen in the corners of IPS screens.

LED-backlit LCD TVs are prone to black uniformity issues, but OLED TVs can produce virtually perfect blacks because their pixels are self-emitting, and therefore don"t have the same limitations caused by improper backlight implementation. That means they don"t suffer from clouding or flashlighting as LED TVs do.

Poorly designed backlight placement. The type of backlight and its position directly affects the uniformity of the screen. The worst uniformity can be found on edge-lit LED TVs, because the LEDs are only on the edge of the screen. Full-array LED TVs have good uniformity because their LEDs are spread out across the whole screen. Some edge-lit TVs have great uniformity. You can learn more about different backlights here.

Non-uniform frame pressure. Both the LCD screen and the diffuser layers are somewhat flexible. A slight difference in pressure on the frame of the television can change the uniformity of the picture. On some televisions, this can be fixed (see below).

Flashlighting can sometimes be fixed on some televisions. If the flashlighting is caused by pressure from the TV"s frame, you can adjust it by slightly loosening or tightening the screws behind the edge of the screen. Some TVs don"t expose the screws, however, so this won"t always be possible. You should also keep in mind that a small change in the tightness of a screw can have a big impact on the uniformity of the screen, so be careful if ever you do try this step. While this can fix the issue, we don"t recommend it unless you know exactly what you"re doing, as it may cause more problems than it solves.

For clouding, there"s a pretty simple fix that—while not guaranteed—can have good results. Power on the TV and display a black image. This will allow you to see the lighter spots on the screen. Next, take a soft cloth and massage those brighter spots to improve the uniformity. You should only apply very gentle pressure, just barely touching the screen. You can also try a few different stroking patterns. If you are patient enough, this works surprisingly often, especially on edge-lit TVs, although you should be very careful to avoid damaging your screen.

Black uniformity refers to how evenly a TV can display black across the screen, especially when displaying a bright object over a dark background. It’s important when watching dark scenes in a dark room, and while most people shouldn’t notice black uniformity issues like flashlighting and clouding, they can become more apparent when the issues are especially bad. You won’t need to worry about these problems in rooms with lights on, though. For each TV, we take a photo of a black frame to capture the black uniformity, and then we calculate the color values of the pixels to find the standard deviation of the uniformity. We then do the same with local dimming enabled.

You may be able to remove flashlighting (to some degree) by tightening the screws of the TV’s frame. This can have pretty dramatic effects on the picture, though, so you should be very careful when attempting this. For clouding, gently massaging problem areas with a soft cloth often does a good job of fixing bad uniformity. In the end, the safest bet may be to simply return or exchange your TV if you can, since uniformity varies between individual units.

Are you having any problems with your TV? Leave your worries! Check on eligibility for warranty and feel free to call TUSA Service Center for our Same-Day In-Home service. 180-day warranty!

Verify if the surge protector or an extension is turned on in case a power cord is connected to these devices. If a TV screen appears black, plug another device into the socket to check whether this device is getting power from the outlet. If power is supplied to the outlet it means that your TV is powering on and a picture issue should be revised. You need to make a call to the TUSA Service Center and our technician will soon revive your TV.

There are many possible problems in case your TV is powered but a TV screen goes black and there is no sound. All you can do in this case at home is to reset your TV to the factory defaults. This procedure is described in the User Manual of your TV.

To double-check this failure press a MENU button installed on the TV to see if TV´s MENU appears on the screen, In case the MENU appears, verify that all video connections are well secured and to appropriate jacks on your TV. If the result is negative, you can trigger the MENU to reset your TV to the factory defaults.

In case neither of the above steps resolved the problem of the TV, you are welcome to get urgent assistance with this problem by contacting the TUSA Service Center.

Sometimes when watching TV, annoying situations arise when a TV screen fades off to black. That is to say, the TV screen goes black at random times and appears to be off but the sound is available and the power light is still illuminating. A troubleshooting procedure may differ for a variety of TV brands but generally will work the same to fix the problem and is as the following:

Connect a different device to the TV or the same device to another TV. The device being used (Ex. Blu-Ray/CABLE BOX) may cause the black screen issue.

A hidden fault within HDMI cable – Replace with new High-Speed HDMI 2.0 cable. Replace the HDMI cable as it may have a short or another defect which causes the black screen issue.

Troubleshoot a video connection from a monitor (or a TV being used as a monitor) to a desktop computer. If your computer has a built-in display, see Screen is Blank after Starting the Computer.

This document will help you determine if the blank screen is being caused by the computer hardware, the video signal to the monitor, or the monitor itself.

If you have a flat panel LCD monitor, unplug the monitor power cable, wait about 30 seconds, reconnect the cable and then turn on the monitor. This resets the electronics on the monitor.

If you do not hear noise from the fans and the power lights on the computer are not on, the problem is related to the computer, not the monitor. To troubleshoot a computer that does not start, see Computer Does Not Start.

If you can hear the computer fan spinning and see lights on the computer, the problem is probably caused by the video cable connection or the monitor. Continue to the next step.

If a message is displayed, the monitor panel is working and the problem is related to the video signal. For further troubleshooting steps, see, Flat Panel Monitor Displays Message about No Signal, Signal out of Range, Sleep, or Power Save.

Some monitors do not have on-screen messages but instead use the lights to indicate no signal. When you disconnect the cable, instead of an on-screen message, the light turns amber, indicating that the monitor lost signal and is working properly, but is out of range, or not receiving the signal.

Connect the computer to another monitor to determine which device has the problem (the monitor or the computer). If you do not have an extra monitor, temporarily connect the computer to another monitor for troubleshooting purposes.

If the monitor still displays a black screen or displays a No signal message, the video hardware may be faulty and needs to be replaced or serviced. If the monitor displays the first startup screen but then goes blank, continue to the next step.

Use this step to configure Windows to use a display resolution that is compatible with the main monitor device. In order to perform these steps, you must connect the computer to another working monitor. If you cannot view the first startup screens, skip to Replace the graphics card or have the hardware serviced.

Use the following steps to change to a compatible display resolution and color depth setting from a standard graphics mode. For flat panel LCD monitors, set the display resolution to the monitor"s native display resolution.

If Windows was recently upgraded, Windows might be starting up into a Power Saving state and producing the blank screen before it loads. After Windows loads (about 2 minutes after turning on the computer), press the power button briefly or press the Suspend key on the keyboard to see if the computer comes out of a suspended state. If the computer opens into a suspended state every time the computer is started, use the following steps to disable Power Saving in the BIOS.

Slowly drag your finger to the bottom right corner without lifting. Try to move your finger slowly enough that you can count to 10 before reaching the opposite corner of the screen.

Under your Pixel 5 phone’s screen, at the top center, you can see a white dot. This white dot is your proximity sensor. When your proximity sensor is on, the dot shows through the display. The dot can blink or stay solid.

Your proximity sensor keeps your phone’s screen off while you hold your phone near your face during a call, when your screen is locked, and when used by certain apps. Keeping the screen off helps save battery and avoid accidental taps on the screen.

All Pixel phones have proximity sensors. Because the Pixel 5’s display goes almost to the edge, you can see the Pixel 5’s sensor under the screen. Check our Pixel 5 phone diagram.

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, digital clocks, calculators, and mobile telephones, including smartphones. LCD screens are also used on consumer electronics products such as DVD players, video game devices and clocks. LCD screens have replaced heavy, bulky cathode-ray tube (CRT) displays in nearly all applications. LCD screens are available in a wider range of screen sizes than CRT and plasma displays, with LCD screens available in sizes ranging from tiny digital watches to very large television receivers. LCDs are slowly being replaced by OLEDs, which can be easily made into different shapes, and have a lower response time, wider color gamut, virtually infinite color contrast and viewing angles, lower weight for a given display size and a slimmer profile (because OLEDs use a single glass or plastic panel whereas LCDs use two glass panels; the thickness of the panels increases with size but the increase is more noticeable on LCDs) and potentially lower power consumption (as the display is only "on" where needed and there is no backlight). OLEDs, however, are more expensive for a given display size due to the very expensive electroluminescent materials or phosphors that they use. Also due to the use of phosphors, OLEDs suffer from screen burn-in and there is currently no way to recycle OLED displays, whereas LCD panels can be recycled, although the technology required to recycle LCDs is not yet widespread. Attempts to maintain the competitiveness of LCDs are quantum dot displays, marketed as SUHD, QLED or Triluminos, which are displays with blue LED backlighting and a Quantum-dot enhancement film (QDEF) that converts part of the blue light into red and green, offering similar performance to an OLED display at a lower price, but the quantum dot layer that gives these displays their characteristics can not yet be recycled.

Since LCD screens do not use phosphors, they rarely suffer 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 are, however, susceptible to image persistence.battery-powered electronic equipment more efficiently than a CRT can be. By 2008, annual sales of televisions with LCD screens exceeded sales of CRT units worldwide, and the CRT became obsolete for most purposes.

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, along with OLED displays, 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 1964, George H. Heilmeier, then working at the RCA laboratories on the effect discovered by Williams achieved the switching of colors by field-induced realignment of dichroic dyes in a homeotropically oriented liquid crystal. Practical problems with this new electro-optical effect made Heilmeier continue to work on scattering effects in liquid crystals and finally the achievement of the first operational liquid-crystal display based on what he called the George H. Heilmeier was inducted in the National Inventors Hall of FameIEEE Milestone.

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,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.

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),

Due to the LCD layer that generates the desired high resolution images at flashing video speeds using very low power electronics in combination with LED based backlight technologies, LCD technology has become the dominant display technology for products such as televisions, desktop monitors, notebooks, tablets, smartphones and mobile phones. Although competing OLED technology is pushed to the market, such OLED displays do not feature the HDR capabilities like LCDs in combination with 2D LED backlight technologies have, reason why the annual market of such LCD-based products is still growing faster (in volume) than OLED-based products while the efficiency of LCDs (and products like portable computers, mobile phones and televisions) may even be further improved by preventing the light to be absorbed in the colour filters of the LCD.

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.

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.

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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