lcd panel layer thickness made in china

One of today’s modern technological wonders is the flat-panel liquid crystal display (LCD) screen, which is the key component we find inside televisions, computer monitors, smartphones, and an ever-proliferating range of gadgets that display information electronically.What most people don’t realize is how complex and sophisticated the manufacturing process is. The entire world’s supply is made within two time zones in East Asia. Unless, of course, the factory proposed by Foxconn for Wisconsin actually gets built.

Liquid crystal display (LCD) screens are manufactured by assembling a sandwich of two thin sheets of glass.On one of the sheets are transistor “cells” formed by first depositing a layer of indium tin oxide (ITO), an unusual metal alloy that you can actually see through.That’s how you can get electrical signals to the middle of a screen.Then you deposit a layer of silicon, followed by a process that builds millions of precisely shaped transistor parts.This patterning step is repeated to build up tiny little cells, one for each dot (known as a pixel) on the screen.Each step has to be precisely aligned to the previous one within a few microns.Remember, the average human hair is 40 microns in diameter.

On the other sheet of glass, you make an array of millions of red, green, and blue dots in a black matrix, called a color filter array (CFA).This is how you produce the colors when you shine light through it.Then you drop tiny amounts of liquid crystal material into the cells on the first sheet and glue the two sheets together.You have to align the two sheets so the colored dots sit right on top of the cells, and you can’t be off by more than a few microns in each direction anywhere on the sheet.The sandwich is next covered with special sheets of polarizing film, and the sheets are cut into individual “panels” – a term that is used to describe the subassembly that actually goes into a TV.

For the sake of efficiency, you would like to make as many panels on a sheet as possible, within the practical limitations of how big a sheet you can handle at a time.The first modern LCD Fabs built in the early 1990s made sheets the size of a single notebook computer screen, and the size grew over time. A Gen 5 sheet, from around 2003, is 1100 x 1300 mm, while a Gen 10.5 sheet is 2940 x 3370 mm (9.6 x 11 ft).The sheets of glass are only 0.5 - 0.7 mm thick or sometimes even thinner, so as you can imagine they are extremely fragile and can really only be handled by robots.The Hefei Gen 10.5 fab is designed to produce the panels for either eight 65 inch or six 75 inch TVs on a single mother glass.If you wanted to make 110 inch TVs, you could make two of them at a time.

The fab is enormous, 1.3 km from one end to the other, divided into three large buildings connected by bridges.LCD fabs are multi-story affairs.The main equipment floor is sandwiched between a ground floor that is filled with chemical pipelines, power distribution, and air handling equipment, and a third floor that also has a lot of air handling and other mechanical equipment.The main equipment floor has to provide a very stable environment with no vibrations, so an LCD fab typically uses far more structural steel in its construction than a typical skyscraper.I visited a Gen 5 fab in Taiwan in 2003, and the plant manager there told me they used three times as much structural steel as Taipei 101, which was the world’s tallest building from 2004- 2010.Since the equipment floor is usually one or two stories up, there are large loading docks on the outside of the building.When they bring the manufacturing equipment in, they load it onto a platform and hoist it with a crane on the outside of the building.That’s one way to recognize an LCD fab from the outside – loading docks on high floors that just open to the outdoors.

LCD fabs have to maintain strict standards of cleanliness inside.Any dust particles in the air could cause defects in the finished displays – tiny dark spots or uneven intensities on your screen.That means the air is passed through elaborate filtration systems and pushed downwards from the ceiling constantly.Workers have to wear special clean room protective clothing and scrub before entering to minimize dust particles or other contamination.People are the largest source of particles, from shedding dead skin cells, dust from cosmetic powders, or smoke particles exhaled from the lungs of workers who smoke.Clean rooms are rated by the number of particles per cubic meter of air.A class 100 cleanroom has less than 100 particles less than 0.3 microns in diameter per cubic meter of air, Class 10 has less than 10 particles, and so on. Fab 9 has hundeds of thousands of square meters of Class 100 cleanroom, and many critical areas like photolithography are Class 10.In comparison, the air in Harvard Square in Cambridge, MA is roughly Class 8,000,000, and probably gets substantially worse when an MBTA bus passes through.

Since most display manufacturing has to be done in a cleanroom and handling the glass requires such precision, the factory is heavily automated.As you watch the glass come in, it is placed into giant cassettes by robot handlers, and the cassettes are moved around throughout the factory.At each step, robots lift a piece of glass out of the cassette, and position it for the processing machines.Some of the machines, like the ones that deposit silicon or ITO, orient the glass vertically, and put them inside an enormous vacuum chamber where all the air is first pumped out before they can go to work.And then they somehow manage to deposit micrometer thin layers that are extremely uniform.It is a miracle that any of this stuff actually works.

The Hefei Gen 10.5 is one of the most sophisticated manufacturing plants in the world.On opening day for the fab, BOE shipped panels to Sony, Samsung Electronics, LG Electronics, Vizio, and Haier.So if you have a new 65 or 75-inch TV, there is some chance the LCD panel came from here.

BEIJING -- China is facing a serious glut of large LCD panels as manufacturers keep boosting output capacity despite the lackluster market, a trend likely to have far-reaching repercussions for related businesses in East Asia.

Local LCD panel producer BOE, now operating a cutting-edge plant in Beijing that can make panels using 8.5-generation (2,200-by-2,500mm) glass substrates, is moving to open similar facilities in Hefei, Anhui Province, and Chongqing, Sichuan Province, by summer 2015.

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OCT is a standard ophthalmologist"s tool for diagnosing and managing retinal pathologies [21–23]. Imaging of the retina has substantially advanced since the development of SD-OCT. Recent studies demonstrated SD-OCT retinal thickness measurements and some inaccuracies in SD-OCT retinal thickness measurements [6, 21, 24–29]. In pathologies where the OCT B-scan image is distorted, automated segmentation may produce inaccurate results due to segmentation errors. In such cases, manual measurements and/or manual correction of segmentation errors may provide more accuracy, which is essential in understanding the pathophysiology of numerous ocular diseases [14]. Subsequently in this study, we measured manually the CFT using the two OCT display modes, which revealed significant differences in retinal thickness measurements based on 1:1 pixel display mode compared to the measurements based on 1:1 micron display mode. Moreover, we found that the differences between the two display modes are correlated to the OCT ITA. The current study shows a significant difference in the measurement of CFT, HFL + ONL thickness, ELM-EZ distance, and EZ-RPE under the two OCT display modes. We found that there is an overestimation of CFT measurement in the 1:1 pixel mode when the OCT image is tilted. It is beneficial to consider the differences between OCT display modes to avoid measurement errors and misinterpretations and to plan for the best management of retinal diseases. In their study, Kim et al. also found differences between the two display modes for choroidal thickness measurement and they found that the subfoveal choroidal thickness (SFCT) was greater in measurements based on the 1:1 pixel mode. A critical overestimation of the SFCT was noted when it was measured on a 1:1 pixel mode. This finding suggested that the estimation of choroidal thickness should be performed based on a 1:1 µm display mode, particularly if the estimation line is not vertical. In addition, as demonstrated in some eyes for foveal retinal thickness, they believed that a similar measurement error can occur when measuring the thickness of other structures when the image of the structure is tilted, which is exactly the case in our current study. In their study, approximately 30% of the images with the 1:1 pixel setting showed a tilted view of the retina/choroid. Their study did not elucidate the exact reason for the tilted images, but suspected the curvature of the eye, especially in case of myopia, poor fixation, head tilt, or tilt OCT camera [30].

In their study, Cho et al. show that 1:1 µm images granted slightly better repeatability in interobserver measurements, and suggested that choroidal thickness measurements must be interpreted with caution, especially for a thick choroid. In their study for both image modes, the SFCT does not significantly vary between the observers (p = 0.5663 for the 1:1 pixel image and p = 0.2839 for the 1:1 micron image, respectively). The mean SFCT was 315.3 ± 89.2 mm in the 1:1 pixel images and 312.6 ± 88.4 mm in the 1:1 micron images based on the two observers’ initial measurements. However, in their study, statistical analysis of the 1:1 pixel images revealed significantly stronger repeatability than the 1:1 micron images [31]. Although Kim et al. showed overestimation in the 1:1 pixel images, these inaccuracies did not appear to have a substantial impact on reproducibility [30]. We realized that the differences between the two display modes in our study are statically more significant than the differences in their studies. This can be explained by the differentiation of the technique of measurement without considering the OCT ITA and also the measured parameters. Marcel et al. performed a study on the reproducibility of retinal thickness measurements in healthy subjects using Spectralis optical coherence tomography system. Their study shows a high reproducibility in the retinal thickness measurement for all the Early Treatment Diabetic Retinopathy Study areas. In their study, the mean foveal thickness is 286 ± 17 µm in the micron display mode in contrast, in our study the mean CFT is 213.33 μm (22.33 μm) in the 1:1 µm mode [6]. This difference can probably be explained by the differences in the study population (emmetropes vs. myopes), the technique of measurement (automatic vs. manual), and the model of OCT machine used (frequency-domain vs. spectral-domain). Previous studies have shown that retinal thickness may be affected by refractive status [32, 33], measurement technique [34], and OCT machine model [35–37].

Despite the reproducibility between the two display modes, previous studies mainly used 1:1 pixel display mode. Although 1:1 pixel display mode shows all acquired pixels, 1:1 micron display mode organizes the pixels using the same scale horizontally and vertically. As a result, to reflect the physical dimensions, the 1:1 micron display mode must be vertically compressed approximately threefold. Even though the 1:1 pixel display mode can more clearly show a precise structural change, a slight deviation from the perpendicular measuring can lead to a large error during manual measurement [31]. However, there is no consensus on whether to use a 1:1 pixel display mode or a 1:1 micron display mode for manual retinal thickness measurement. As a result, the type of image used for measuring CFT is at the discretion of each investigator the same as for CT manual measurement. In some previous studies, measurements were based on 1:1 pixel display mode [38–44], whereas others used 1:1 micron display mode [45–48].

Since there is no agreement on whether to use 1:1 pixel display mode or 1:1 micron display mode for thickness measurement, methods to convert the values between different display modes are warranted. Our research found correlations between the differences in retinal thickness and the OCT ITA. We found that the more the OCT B-scan image was tilted, the more differences in retinal thickness were observed. This finding may be due to different vertical-to-horizontal scale ratios in the two display modes. As the ITA is increased, the CFT is more over-estimated by the 1:1 pixel mode because the ratio is 3.775 in this mode while it is 1 in the 1:1 micron mode. We then provided equations produced by the regression models to calculate the differences between the two display modes according to the OCT ITA on the B-scan image. Further studies are needed to validate the reliability of these equations, and before that they should be applied with caution.

The differences in retinal thickness between the two display modes were correlated with the OCT ITA, but not with SE or AL. Such differences could also be affected by the angle kappa and shape of the posterior pole, since both can affect the horizontality of the OCT B-scans. Therefore, in any case, where the OCT B-scan image is tilted, the difference in retinal thickness measurement should be considered. The limitation of the current study is that it only describes the differences at a single center and in myopic patients, and the retinal thickness was only measured at the central fovea. Whether our findings can be generalized to other patients (hyperopes or emmetropes) and other retinal locations needs to be validated.

Since it is difficult to ensure that the probe tip is sitting on the highest peaks of the surface profile, the preferred option is to place a plastic shim of a known thickness that is close to the expected thickness of the applied coating between the probe and substrate and adjust to the stated thickness of the shim- referred to as a 1-point adjustment. The plastic shim sits on the peaks of the surface profile over a greater area than the probe tip, ensuring that the adjustment is being taken ‘over the peaks’. This best simulates a coating covering the peaks of the surface profile.

If access to the bare substrate is not possible, another option is to use the PosiTector Zero Offset feature in accordance with ISO 19840. The Zero Offset adjustment is useful when measuring paint and coating thickness over rough or blasted substrates without access to the uncoated representative substrate. Predefined Zero Offset values can be selected according to the blast profile height. Alternatively, a custom Zero Offset can be entered.

An organic light-emitting diode (OLED or organic LED), also known as organic electroluminescent (organic EL) diode,light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light in response to an electric current. This organic layer is situated between two electrodes; typically, at least one of these electrodes is transparent. OLEDs are used to create digital displays in devices such as television screens, computer monitors, and portable systems such as smartphones and handheld game consoles. A major area of research is the development of white OLED devices for use in solid-state lighting applications.

An OLED display works without a backlight because it emits its own visible light. Thus, it can display deep black levels and can be thinner and lighter than a liquid crystal display (LCD). In low ambient light conditions (such as a dark room), an OLED screen can achieve a higher contrast ratio than an LCD, regardless of whether the LCD uses cold cathode fluorescent lamps or an LED backlight. OLED displays are made in the same way as LCDs, but after TFT (for active matrix displays), addressable grid (for passive matrix displays) or indium-tin oxide (ITO) segment (for segment displays) formation, the display is coated with hole injection, transport and blocking layers, as well with electroluminescent material after the first 2 layers, after which ITO or metal may be applied again as a cathode and later the entire stack of materials is encapsulated. The TFT layer, addressable grid or ITO segments serve as or are connected to the anode, which may be made of ITO or metal.transparent displays being used in smartphones with optical fingerprint scanners and flexible displays being used in foldable smartphones.

Pope"s group reported in 1965exciton energy level. Also in 1965, Wolfgang Helfrich and W. G. Schneider of the National Research Council in Canada produced double injection recombination electroluminescence for the first time in an anthracene single crystal using hole and electron injecting electrodes,Dow Chemical researchers patented a method of preparing electroluminescent cells using high-voltage (500–1500 V) AC-driven (100–3000Hz) electrically insulated one millimetre thin layers of a melted phosphor consisting of ground anthracene powder, tetracene, and graphite powder.

On 5 December 2017, JOLED, the successor of Sony and Panasonic"s printable OLED business units, began the world"s first commercial shipment of inkjet-printed OLED panels.

A typical OLED is composed of a layer of organic materials situated between two electrodes, the anode and cathode, all deposited on a substrate. The organic molecules are electrically conductive as a result of delocalization of pi electrons caused by conjugation over part or all of the molecule. These materials have conductivity levels ranging from insulators to conductors, and are therefore considered organic semiconductors. The highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) of organic semiconductors are analogous to the valence and conduction bands of inorganic semiconductors.

Originally, the most basic polymer OLEDs consisted of a single organic layer. One example was the first light-emitting device synthesised by J. H. Burroughes et al., which involved a single layer of poly(p-phenylene vinylene). However multilayer OLEDs can be fabricated with two or more layers in order to improve device efficiency. As well as conductive properties, different materials may be chosen to aid charge injection at electrodes by providing a more gradual electronic profile,quantum efficiency (up to 19%) by using a graded heterojunction.

During operation, a voltage is applied across the OLED such that the anode is positive with respect to the cathode. Anodes are picked based upon the quality of their optical transparency, electrical conductivity, and chemical stability.electrons flows through the device from cathode to anode, as electrons are injected into the LUMO of the organic layer at the cathode and withdrawn from the HOMO at the anode. This latter process may also be described as the injection of electron holes into the HOMO. Electrostatic forces bring the electrons and the holes towards each other and they recombine forming an exciton, a bound state of the electron and hole. This happens closer to the electron-transport layer part of the emissive layer, because in organic semiconductors holes are generally more mobile than electrons. The decay of this excited state results in a relaxation of the energy levels of the electron, accompanied by emission of radiation whose frequency is in the visible region. The frequency of this radiation depends on the band gap of the material, in this case the difference in energy between the HOMO and LUMO.

Indium tin oxide (ITO) is commonly used as the anode material. It is transparent to visible light and has a high work function which promotes injection of holes into the HOMO level of the organic layer. A second conductive (injection) layer is typically added, which may consist of PEDOT:PSS,barium and calcium are often used for the cathode as they have low work functions which promote injection of electrons into the LUMO of the organic layer.aluminium to avoid degradation. Two secondary benefits of the aluminum capping layer include robustness to electrical contacts and the back reflection of emitted light out to the transparent ITO layer.

Experimental research has proven that the properties of the anode, specifically the anode/hole transport layer (HTL) interface topography plays a major role in the efficiency, performance, and lifetime of organic light-emitting diodes. Imperfections in the surface of the anode decrease anode-organic film interface adhesion, increase electrical resistance, and allow for more frequent formation of non-emissive dark spots in the OLED material adversely affecting lifetime. Mechanisms to decrease anode roughness for ITO/glass substrates include the use of thin films and self-assembled monolayers. Also, alternative substrates and anode materials are being considered to increase OLED performance and lifetime. Possible examples include single crystal sapphire substrates treated with gold (Au) film anodes yielding lower work functions, operating voltages, electrical resistance values, and increasing lifetime of OLEDs.

Balanced charge injection and transfer are required to get high internal efficiency, pure emission of luminance layer without contaminated emission from charge transporting layers, and high stability. A common way to balance charge is optimizing the thickness of the charge transporting layers but is hard to control. Another way is using the exciplex. Exciplex formed between hole-transporting (p-type) and electron-transporting (n-type) side chains to localize electron-hole pairs. Energy is then transferred to luminophore and provide high efficiency. An example of using exciplex is grafting Oxadiazole and carbazole side units in red diketopyrrolopyrrole-doped Copolymer main chain shows improved external quantum efficiency and color purity in no optimized OLED.

Molecules commonly used in OLEDs include organometallic chelates (for example Alq3, used in the organic light-emitting device reported by Tang et al.), fluorescent and phosphorescent dyes and conjugated dendrimers. A number of materials are used for their charge transport properties, for example triphenylamine and derivatives are commonly used as materials for hole transport layers.perylene, rubrene and quinacridone derivatives are often used.3 has been used as a green emitter, electron transport material and as a host for yellow and red emitting dyes.

In the case of OLED, that means the cavity in a TEOLED could be especially designed to enhance the light output intensity and color purity with a narrow band of wavelengths, without consuming more power. In TEOLEDs, the microcavity effect commonly occurs, and when and how to restrain or make use of this effect is indispensable for device design. To match the conditions of constructive interference, different layer thicknesses are applied according to the resonance wavelength of that specific color. The thickness conditions are carefully designed and engineered according to the peak resonance emitting wavelengths of the blue (460 nm), green (530 nm), and red (610 nm) color LEDs. This technology greatly improves the light-emission efficiency of OLEDs, and are able to achieve a wider color gamut due to high color purity.

Patternable organic light-emitting devices use a light or heat activated electroactive layer. A latent material (PEDOT-TMA) is included in this layer that, upon activation, becomes highly efficient as a hole injection layer. Using this process, light-emitting devices with arbitrary patterns can be prepared.

Organic vapour jet printing (OVJP) uses an inert carrier gas, such as argon or nitrogen, to transport evaporated organic molecules (as in organic vapour phase deposition). The gas is expelled through a micrometre-sized nozzle or nozzle array close to the substrate as it is being translated. This allows printing arbitrary multilayer patterns without the use of solvents.

Like ink jet material deposition, inkjet etching (IJE) deposits precise amounts of solvent onto a substrate designed to selectively dissolve the substrate material and induce a structure or pattern. Inkjet etching of polymer layers in OLED"s can be used to increase the overall out-coupling efficiency. In OLEDs, light produced from the emissive layers of the OLED is partially transmitted out of the device and partially trapped inside the device by total internal reflection (TIR). This trapped light is wave-guided along the interior of the device until it reaches an edge where it is dissipated by either absorption or emission. Inkjet etching can be used to selectively alter the polymeric layers of OLED structures to decrease overall TIR and increase out-coupling efficiency of the OLED. Compared to a non-etched polymer layer, the structured polymer layer in the OLED structure from the IJE process helps to decrease the TIR of the OLED device. IJE solvents are commonly organic instead of water-based due to their non-acidic nature and ability to effectively dissolve materials at temperatures under the boiling point of water.

Transfer-printing is an emerging technology to assemble large numbers of parallel OLED and AMOLED devices efficiently. It takes advantage of standard metal deposition, photolithography, and etching to create alignment marks commonly on glass or other device substrates. Thin polymer adhesive layers are applied to enhance resistance to particles and surface defects. Microscale ICs are transfer-printed onto the adhesive surface and then baked to fully cure adhesive layers. An additional photosensitive polymer layer is applied to the substrate to account for the topography caused by the printed ICs, reintroducing a flat surface. Photolithography and etching removes some polymer layers to uncover conductive pads on the ICs. Afterwards, the anode layer is applied to the device backplane to form the bottom electrode. OLED layers are applied to the anode layer with conventional vapor deposition, and covered with a conductive metal electrode layer. As of 2011mm × 400mm. This size limit needs to expand for transfer-printing to become a common process for the fabrication of large OLED/AMOLED displays.

For a high resolution display like a TV, a thin-film transistor (TFT) backplane is necessary to drive the pixels correctly. As of 2019, low-temperature polycrystalline silicon (LTPS)– TFT is widely used for commercial AMOLED displays. LTPS-TFT has variation of the performance in a display, so various compensation circuits have been reported.excimer laser used for LTPS, the AMOLED size was limited. To cope with the hurdle related to the panel size, amorphous-silicon/microcrystalline-silicon backplanes have been reported with large display prototype demonstrations.indium gallium zinc oxide (IGZO) backplane can also be used.

OLEDs can be printed onto any suitable substrate by an inkjet printer or even by screen printing,plasma displays. However, fabrication of the OLED substrate as of 2018 is costlier than that for TFT LCDs.registration — lining up the different printed layers to the required degree of accuracy.

OLEDs enable a greater contrast ratio and wider viewing angle compared to LCDs, because OLED pixels emit light directly. This also provides a deeper black level, since a black OLED display emits no light. Furthermore, OLED pixel colors appear correct and unshifted, even as the viewing angle approaches 90° from the normal.

LCDs filter the light emitted from a backlight, allowing a small fraction of light through. Thus, they cannot show true black. However, an inactive OLED element does not produce light or consume power, allowing true blacks.nm. The refractive value and the matching of the optical IMLs property, including the device structure parameters, also enhance the emission intensity at these thicknesses.

OLEDs also have a much faster response time than an LCD. Using response time compensation technologies, the fastest modern LCDs can reach response times as low as 1ms for their fastest color transition, and are capable of refresh frequencies as high as 240Hz. According to LG, OLED response times are up to 1,000 times faster than LCD,μs (0.01ms), which could theoretically accommodate refresh frequencies approaching 100kHz (100,000Hz). Due to their extremely fast response time, OLED displays can also be easily designed to be strobed, creating an effect similar to CRT flicker in order to avoid the sample-and-hold behavior seen on both LCDs and some OLED displays, which creates the perception of motion blur.

The biggest technical problem for OLEDs is the limited lifetime of the organic materials. One 2008 technical report on an OLED TV panel found that after 1,000hours, the blue luminance degraded by 12%, the red by 7% and the green by 8%.hours to half original brightness (five years at eight hours per day) when used for flat-panel displays. This is lower than the typical lifetime of LCD, LED or PDP technology; each rated for about 25,000–40,000hours to half brightness, depending on manufacturer and model. One major challenge for OLED displays is the formation of dark spots due to the ingress of oxygen and moisture, which degrades the organic material over time whether or not the display is powered.

However, some manufacturers" displays aim to increase the lifespan of OLED displays, pushing their expected life past that of LCD displays by improving light outcoupling, thus achieving the same brightness at a lower drive current.cd/m2 of luminance for over 198,000hours for green OLEDs and 62,000hours for blue OLEDs.hours for red, 1,450,000hours for yellow and 400,000hours for green at an initial luminance of 1,000cd/m2.

Degradation occurs three orders of magnitude faster when exposed to moisture than when exposed to oxygen. Encapsulation can be performed by applying an epoxy adhesive with dessicant,Atomic Layer Deposition (ALD). The encapsulation process is carried out under a nitrogen environment, using UV-curable LOCA glue and the electroluminescent and electrode material deposition processes are carried out under a high vacuum. The encapsulation and material deposition processes are carried out by a single machine, after the Thin-film transistors have been applied. The transistors are applied in a process that is the same for LCDs. The electroluminescent materials can also be applied using inkjet printing.

Improvements to the efficiency and lifetime of blue OLEDs is vital to the success of OLEDs as replacements for LCD technology. Considerable research has been invested in developing blue OLEDs with high external quantum efficiency, as well as a deeper blue color.

Since 2012, research focuses on organic materials exhibiting thermally activated delayed fluorescence (TADF), discovered at Kyushu University OPERA and UC Santa Barbara CPOS. TADF would allow stable and high-efficiency solution processable (meaning that the organic materials are layered in solutions producing thinner layers) blue emitters, with internal quantum efficiencies reaching 100%.

As an emissive display technology, OLEDs rely completely upon converting electricity to light, unlike most LCDs which are to some extent reflective. E-paper leads the way in efficiency with ~ 33% ambient light reflectivity, enabling the display to be used without any internal light source. The metallic cathode in an OLED acts as a mirror, with reflectance approaching 80%, leading to poor readability in bright ambient light such as outdoors. However, with the proper application of a circular polarizer and antireflective coatings, the diffuse reflectance can be reduced to less than 0.1%. With 10,000 fc incident illumination (typical test condition for simulating outdoor illumination), that yields an approximate photopic contrast of 5:1. Advances in OLED technologies, however, enable OLEDs to become actually better than LCDs in bright sunlight. The AMOLED display in the Galaxy S5, for example, was found to outperform all LCD displays on the market in terms of power usage, brightness and reflectance.

While an OLED will consume around 40% of the power of an LCD displaying an image that is primarily black, for the majority of images it will consume 60–80% of the power of an LCD. However, an OLED can use more than 300% power to display an image with a white background, such as a document or web site.

OLED technology is used in commercial applications such as displays for mobile phones and portable digital media players, car radios and digital cameras among others, as well as lighting.Philips Lighting has made OLED lighting samples under the brand name "Lumiblade" available onlineNovaled AG based in Dresden, Germany, introduced a line of OLED desk lamps called "Victory" in September, 2011.

The Google and HTC Nexus One smartphone includes an AMOLED screen, as does HTC"s own Desire and Legend phones. However, due to supply shortages of the Samsung-produced displays, certain HTC models will use Sony"s SLCD displays in the future,Nexus S smartphone will use "Super Clear LCD" instead in some countries.

OLED displays were used in watches made by Fossil (JR-9465) and Diesel (DZ-7086). Other manufacturers of OLED panels include Anwell Technologies Limited (Hong Kong),AU Optronics (Taiwan),Chimei Innolux Corporation (Taiwan),LG (Korea),

The number of automakers using OLEDs is still rare and limited to the high-end of the market. For example, the 2010 Lexus RX features an OLED display instead of a thin film transistor (TFT-LCD) display.

In October 2008, Samsung showcased the world"s thinnest OLED display, also the first to be "flappable" and bendable.mm (thinner than paper), yet a Samsung staff member said that it is "technically possible to make the panel thinner".cd/m2. The colour reproduction range is 100% of the NTSC standard.

At the 2007, Las Vegas Consumer Electronics Show (CES), Sony showcased a 11-inch (28 cm), (resolution 960×540) and 27-inch (69 cm), full HD resolution at 1920 × 1080 OLED TV models.contrast ratios and total thicknesses (including bezels) of 5mm. In April 2007, Sony announced it would manufacture 1000 11-inch (28 cm) OLED TVs per month for market testing purposes.XEL-1, was the first commercial OLED TV

In May 2007, Sony publicly unveiled a video of a 2.5-inch (6.4 cm) flexible OLED screen which is only 0.3 millimeters thick.mm thick 3.5 inches (8.9 cm) display with a resolution of 320×200 pixels and a 0.3mm thick 11-inch (28 cm) display with 960×540 pixels resolution, one-tenth the thickness of the XEL-1.

In October 2008, Sony published results of research it carried out with the Max Planck Institute over the possibility of mass-market bending displays, which could replace rigid LCDs and plasma screens. Eventually, bendable, see-through displays could be stacked to produce 3D images with much greater contrast ratios and viewing angles than existing products.

Lumiotec is the first company in the world developing and selling, since January 2011, mass-produced OLED lighting panels with such brightness and long lifetime. Lumiotec is a joint venture of Mitsubishi Heavy Industries, ROHM, Toppan Printing, and Mitsui & Co.

On 6 January 2016, Dell announced the Ultrasharp UP3017Q OLED monitor at the Consumer Electronics Show in Las Vegas.Hz refresh rate, 0.1 millisecond response time, and a contrast ratio of 400,000:1. The monitor was set to sell at a price of $4,999 and release in March, 2016, just a few months later. As the end of March rolled around, the monitor was not released to the market and Dell did not speak on reasons for the delay. Reports suggested that Dell canceled the monitor as the company was unhappy with the image quality of the OLED panel, especially the amount of color drift that it displayed when you viewed the monitor from the sides.Hz refresh rate and a contrast ratio of 1,000,000:1. As of June, 2017, the monitor is no longer available to purchase from Dell"s website.

Apple began using OLED panels in its watches in 2015 and in its laptops in 2016 with the introduction of an OLED touchbar to the MacBook Pro.iPhone X with their own optimized OLED display licensed from Universal Display Corporation.iPhone XS and iPhone XS Max, and iPhone 11 Pro and iPhone 11 Pro Max.

A third model of Nintendo"s Switch, a hybrid gaming system, features an OLED panel in place of the original model"s LCD panel. Announced in the summer of 2021, it was released on 8 October 2021.

In 2014, Mitsubishi Chemical Corporation (MCC), a subsidiary of Mitsubishi Chemical Holdings, developed an OLED panel with a 30,000-hour life, twice that of conventional OLED panels.

On 18 October 2018, Samsung showed of their research roadmap at their 2018 Samsung OLED Forum. This included Fingerprint on Display (FoD), Under Panel Sensor (UPS), Haptic on Display (HoD) and Sound on Display (SoD).

Flat-panel electronic displays: a triumph of physics, chemistry and engineering, Philosophical Transactions of the Royal Society, Volume 368, Issue 1914

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Abstract: The present invention provides a thin film transistor array substrate and a manufacture method thereof, comprising: a substrate (1) and a thin film transistor and a storage capacitor formed on the substrate (1); the storage capacitor comprises a first electrode plate (31) on the substrate (1), a gate isolation layer (31) or an etching stopper layer (5) on the first electrode plate (31), a second electrode plate (32) on the gate isolation layer (3) or the etching stopper layer (5); there is only one isolation layer, which is the gate isolation layer or the etching stopper layer, existing between the two electrode plates of the storage capacitor in the aforesaid thin film transistor array substrate, the isolation layer thickness of the storage capacitor is thinner, and relatively, the capacitor occupies a smaller area and possesses a higher aperture ratio.

Abstract: The present invention provides a drive method and a drive device of a liquid crystal display, and the drive method comprises: receiving an image to display; selecting one color washout compensation mode from several different color washout compensation modes according to the user selection or the display mode, and implementing color washout compensation to the image to display; driving the liquid crystal panel to show the image to display after the color washout compensation. With the aforesaid arrangement, the present invention can reduce the color washout under large view angle to promote the display effect of the large view angle.

Abstract: The present invention discloses a display apparatus, comprising: a control unit, employed for setting an image display period and a touch sense period and generating image display data, a first control signal and a second control signal; a display panel, employed for displaying images and generating a touch sense signal. The present invention also discloses a method of image display and touch sense of a display apparatus. The present invention integrates the image display function and the touch sense function without stacking the touch panel and promotes the display quality.

Abstract: Disclosed is a method for detecting defects of a TFT array substrate. The method comprises steps of: positioning an abnormal area of the TFT array substrate; separating the abnormal area from other areas of the array substrate; and treating the abnormal area as such that multiple layers in the abnormal area can be revealed one by one, and detecting the revealed layers to determine a defective layer in the abnormal area.

Abstract: A liquid crystal display (LCD) panel and an LCD device are provided. The panel has: a first transparent conductive layer configured to introduce a first polarity electric charge accumulated on a first substrate, a second transparent conductive layer configured to introduce a second polarity electric charge accumulated on a second substrate, and a connecting component disposed on the first substrate and/or the second substrate. Only when pressing the liquid crystal display panel, the first transparent conductive layer and the second transparent conductive layer are electrically connected to each other by the connecting component.

Abstract: The present invention provides an array substrate and a manufacture method thereof. The array substrate, by locating both a black matrix and a color resist layer on the array substrate, and locating the color resist layer on the TFT layer prevents the bad influence to the color resist layer from the high temperature TFT process, and accordingly to make the liquid crystal panel with higher display quality. The manufacture method of the array substrate, first forms a black matrix on the substrate, and second implements TFT manufacture process on the black matrix, and then forms a color resist layer after the TFT manufacture.

Abstract: An alignment film drying system and a method for drying alignment films are proposed. The alignment film drying system is used for drying an alignment film coated on a substrate. The alignment film drying system includes a plurality of magnetrons. The alignment liquid is coated on one side of the substrate facing the plurality of magnetrons and is heated through electromagnetic radiation produced by the plurality of magnetrons. The dried alignment liquid forms an alignment film having a uniform thickness, which ensures that the display effect of LCDs is better.

Abstract: A display panel and an image display method for using in the display panel are provided. The display panel comprises first pixel rows and second pixel rows, the first pixel row is adapted for displaying a three-dimensional image according to a three-dimensional image data and the second pixel row is adapted for displaying a luminance compensated image corresponding to a luminance compensated data according to the luminance compensated data so as to increase a brightness of a screen composed of the three-dimensional image and the luminance compensated image. This increases the brightness of the three-dimensional image displayed by the display panel.

Abstract: An adjusting method of display parameter and a liquid crystal display (LCD) system are provided. The adjusting method includes: obtaining a first luminance value and a second luminance value when a LCD panel displaying a minimum grayscale image and a maximum grayscale image respectively; based on the first luminance value, the second luminance value and a standard Gamma curve of the LCD panel, obtaining each target luminance value conforming to the standard Gamma curve and corresponding to each grayscale; based on the target luminance value of each grayscale and a relationship between grayscale voltage and luminance obtained in advance, obtaining a target grayscale voltage of each grayscale; and adjusting a grayscale voltage of each grayscale to be the target grayscale voltage of the grayscale to thereby achieve Gamma adjustment. By the above method, automatic adjustment of display parameter for the LCD panel can be achieved.

Abstract: A includes a switch TFT and a drive TFT. The switch TFT is formed of a first source and a first drain, a first gate, and a first etching stopper layer, and a first oxide semiconductor layer and first gate isolation layer sandwiched therebetween. The drive TFT is formed of a second source and a second drain, a second gate, and a second oxide semiconductor layer, and a first etching stopper layer and a second gate isolation layer sandwiched therebetween. The electrical properties of the switch TFT and the drive TFT are different. The switch TFT has a smaller subthreshold swing to achieve fast charge and discharge, and the drive TFT has a relatively larger subthreshold swing for controlling a current and a grey scale more precisely.

Abstract: The present disclosure discloses a HSD liquid crystal display panel, a display device and a driving method thereof. Said display panel comprises a plurality of sub pixel unit groups connected with data lines and scanning lines, wherein each data line comprises a plurality of winding parts; and wherein the sub pixel unit groups that are spaced from each other by k rows and connected to data line i and the sub pixel unit groups that are spaced from each other by k rows and connected to data line i+m are located in the same column group, so that during display driving the polarity of a sub pixel unit group is opposite to that of its adjacent sub pixel unit group in the same row, and the polarity of a sub pixel unit group is the same as that of the sub pixel unit group which is spaced from said sub pixel unit group by k rows in the same column group, i and k being positive integers and m being odd number.

In recent years, with the rapid development of China"s high generation LCD panel industry, related industry chain development is also in full swing, Polaroid flat panel display as one of the most important supporting materials industry, also ushered in a rare development opportunity, and gradually localization, in this process, Shenzhen City three tiptop photoelectric Polytron Technologies Inc (hereinafter abbreviation: Sanli plays the role of forerunner spectrum), the future will continue to enjoy the huge growth space localization alternative polarizer.

As everyone knows, the polarizing film of high technical threshold, before the market dominated by several major manufacturers of LG chemistry, chemistry, etc. Sumitomo ensequence foreign monopoly. But with the transfer of the global panel business to the domestic market, the trend of polarizing industry transfer to the mainland has also been formed. For the growing domestic panel capacity, the urgent demand for the polarizing film localization is increasing.

Past industry experience shows that the rise of panel industry in a region must be accompanied by the rapid development of supporting industries in the global panel, the third panel industry transfer tide, China"s end panel manufacturing has been in the forefront to become the world"s first, and the polarizing liquid crystal panel as the most important raw materials, its development is still subject to South Korea Taiwan suppress competition rivals such as productivity advantages and technical advantages, but the trend of industrial transfer, Japanese manufacturers have basically no new production capacity, with special authorization of the technical cooperation, South Korea Taiwan polarizer manufacturers are also actively in the expansion of domestic, is particularly important for domestic manufacturers at this stage of the expansion of the window period is.

At present, three physical has numerous applications to meet the downstream demand of Polaroid production capacity. The product types include TN polarizer, STN polarizer, TFT polarizer, OLED polarizer and 3D glasses polarizer. The effective thickness of the product is the thinnest that has reached 90m, and can provide 120m, 130m, 150m, 210m and other different thickness products. At the same time, the company can provide different types and thickness matching products to support customers" product design according to customer needs, and jointly develop special polarized products with customers.

Polarizer, as one of the key raw materials of LCD panel, has been strongly supported by the national industrial policy. In recent years, the state has continuously increased its support for the flat panel display industry, especially the LCD panel industry.

At present, the domestic LCD panel production capacity has been ranked first in the world, while domestic panel makers still further accelerated the high generation panel production line construction progress, and promote domestic Polaroid demand growth, although foreign investment increase in domestic production capacity construction, but there are still a large gap between supply and demand.

According to statistics, the current domestic Polaroid accounted for less than 40% of domestic demand, to 2019 self-sufficiency rate is expected to increase to 65%, is expected to 2019 domestic demand for TFT-LCD panel factory Polaroid polarizer of about 185 million square meters, OLED needs about 9 million 580 thousand square meters, and almost all are increasing demand for capacity planning; to 2019 domestic manufacturers look at the supply of only 120 million square meters, there is a big gap between supply and demand, as one of the polarizer panel core material, the panel cost accounted for about 10%, to accelerate the localization of materials is one of the important starting point for the downstream panel manufacturers in the future to further improve the cost competitiveness, in line with industry rules - the rise of downstream upstream material substitution accelerate domestic drive. With the rapid growth of demand and the rise of domestic panel manufacturers, domestic polarizer will usher in the best opportunity for development. Three physical will take this wind, become a polarizing film industry rise directly to a high position, the leading solutions provider with international competitiveness.

► When the leading Korean players Samsung Display and LG Display exit LCD production, BOE will be the most significant player in the LCD market. Though OLED can replace the LCD, it will take years for it to be fully replaced.

► As foreign companies control evaporation material and machines, panel manufacturers seek a cheaper way to mass-produce OLED panels – inkjet printing.

When mainstream consumer electronics brands choose their device panels, the top three choices are Samsung Display, LG Display (LGD) and BOE (000725:SZ) – the first two from Korea and the third from China. From liquid-crystal displays (LCD) to active-matrix organic light-emitting diode (AMOLED), display panel technology has been upgrading with bigger screen products.

From the early 1990s, LCDs appeared and replaced cathode-ray tube (CRT) screens, which enabled lighter and thinner display devices. Japanese electronics companies like JDI pioneered the panel technology upgrade while Samsung Display and LGD were nobodies in the field. Every technology upgrade or revolution is a chance for new players to disrupt the old paradigm.

The landscape was changed in 2001 when Korean players firstly made a breakthrough in the Gen 5 panel technology – the later the generation, the bigger the panel size. A large panel size allows display manufacturers to cut more display screens from one panel and create bigger-screen products. "The bigger the better" is a motto for panel makers as the cost can be controlled better and they can offer bigger-size products to satisfy the burgeoning middle-class" needs.

LCD panel makers have been striving to realize bigger-size products in the past four decades. The technology breakthrough of Gen 5 in 2002 made big-screen LCD TV available and it sent Samsung Display and LGD to the front row, squeezing the market share of Japanese panel makers.

The throne chair of LCD passed from Japanese companies to Korean enterprises – and now Chinese players are clinching it, replacing the Koreans. After twenty years of development, Chinese panel makers have mastered LCD panel technology and actively engage in large panel R&D projects. Mass production created a supply surplus that led to drops in LCD price. In May 2020, Samsung Display announced that it would shut down all LCD fabs in China and Korea but concentrate on quantum dot LCD (Samsung calls it QLED) production; LGD stated that it would close LCD TV panel fabs in Korea and focus on organic LED (OLED). Their retreats left BOE and China Stars to digest the LCD market share.

Consumer preference has been changing during the Korean fab"s recession: Bigger-or-not is fine but better image quality ranks first. While LCD needs the backlight to show colors and substrates for the liquid crystal layer, OLED enables lighter and flexible screens (curvy or foldable), higher resolution and improved color display. It itself can emit lights – no backlight or liquid layer is needed. With the above advantages, OLED has been replacing the less-profitable LCD screens.

Samsung Display has been the major screen supplier for high-end consumer electronics, like its own flagship cell phone products and Apple"s iPhone series. LGD dominated the large OLED TV market as it is the one that handles large-size OLED mass production. To further understand Korean panel makers" monopolizing position, it is worth mentioning fine metal mask (FMM), a critical part of the OLED RGB evaporation process – a process in OLED mass production that significantly affects the yield rate.

Prior to 2018, Samsung Display and DNP"s monopolistic supply contract prevented other panel fabs from acquiring quality FMM products as DNP bonded with Hitachi Metal, the "only" FMM material provider choice for OLED makers. After the contract expired, panel makers like BOE could purchase FFM from DNP for their OLED R&D and mass production. Except for FFM materials, vacuum evaporation equipment is dominated by Canon Tokki, a Japanese company. Its role in the OLED industry resembles that of ASML in the integrated circuit space. Canon Tokki"s annual production of vacuum evaporation equipment is fewer than ten and thereby limits the total production of OLED panels that rely on evaporation technology.

The shortage of equipment and scarcity of materials inspired panel fabs to explore substitute technology; they discovered that inkjet printing has the potential to be the thing to replace evaporation. Plus, evaporation could be applied to QLED panels as quantum dots are difficult to be vaporized. Inkjet printing prints materials (liquefied organic gas or quantum dots) to substrates, saving materials and breaking free from FMM"s size restriction. With the new tech, large-size OLED panels can theoretically be recognized with improved yield rate and cost-efficiency. However, the tech is at an early stage when inkjet printing precision could not meet panel manufacturers" requirements.

Display and LGD are using evaporation on their OLED products. To summarize, OLED currently adopts evaporation and QLED must go with inkjet printing, but evaporation is a more mature tech. Technology adoption will determine a different track for the company to pursue. With inkjet printing technology, players are at a similar starting point, which is a chance for all to run to the front – so it is for Chinese panel fabs. Certainly, panel production involves more technologies (like flexible panels) than evaporation or inkjet printing and only mastering all required technologies can help a company to compete at the same level.

Presently, Chinese panel fabs are investing heavily in OLED production while betting on QLED. BOE has four Gen 6 OLED product lines, four Gen 8.5 and one Gen 10.5 LCD lines; China Star, controlled by the major appliance titan TCL, has invested two Gen 6 OLED fabs and four large-size LCD product lines.

Remembering the last "regime change" that occurred in 2005 when Korean fabs overtook Japanese" place in the LCD market, the new phase of panel technology changed the outlook of the industry. Now, OLED or QLED could mark the perfect time for us to expect landscape change.

After Samsung Display and LGD ceding from LCD TV productions, the vacant market share will be digested by BOE, China Star and other LCD makers. Indeed, OLED and QLED have the potential to take over the LCD market in the future, but the process may take more than a decade. Korean companies took ten years from panel fab"s research on OLED to mass production of small- and medium-size OLED electronics. Yet, LCD screen cell phones are still available in the market.

LCD will not disappear until OLED/QLED"s cost control can compete with it. The low- to middle-end panel market still prefers cheap LCD devices and consumers are satisfied with LCD products – thicker but cheaper. BOE has been the largest TV panel maker since 2019. As estimated by Informa, BOE and China Star will hold a duopoly on the flat panel display market.

BOE"s performance seems to have ridden on a roller coaster ride in the past several years. Large-size panel mass production like Gen 8.5 and Gen 10.5 fabs helped BOE recognize the first place in production volume. On the other side, expanded large-size panel factories and expenses of OLED product lines are costly: BOE planned to spend CNY 176.24 billion (USD 25.92 billion) – more than Tibet"s 2019 GDP CNY 169.78 billion – on Chengdu and Mianyang"s Gen 6 AMOLED lines and Hefei and Wuhan"s Gen 10.5 LCD lines.

Except for making large-size TVs, bigger panels can cut out more display screens for smaller devices like laptops and cell phones, which are more profitable than TV products. On its first-half earnings concall, BOE said that it is shifting its production focus to cell phone and laptop products as they are more profitable than TV products. TV, IT and cell phone products counted for 30%, 44% and 33% of its productions respectively and the recent rising TV price may lead to an increased portion of TV products in the short term.

Except for outdoor large screens, TV is another driver that pushes panel makers to research on how to make bigger and bigger screens. A research done by CHEARI showed that Chinese TV sales dropped by 10.6% to CNY 128.2 billion from 2018 to 2019. Large-size TV sales increased as a total but the unit price decreased; high-end products like laser TV and OLED TV saw a strong growth of 131.2% and 34.1%, respectively.

The demand for different products may vary as lifestyles change and panel fabs need to make on-time judgments and respond to the change. For instance, the coming Olympics is a new driving factor to boost TV sales; "smart city" projects around the world will need more screens for data visualization; people will own more screens and better screens when life quality improves. Flexible screens, cost-efficient production process, accessible materials, changing market and all these problems are indeed the next opportunity for the industry.

Automotive head-up display (HUD) systems include a projector that projects light onto the windshield. This light is then reflected into the driver"s eyes and appears as a virtual image on top of the hood of the car, at a comfortable viewing distance from the driver.1 The image source of the HUD projector, however, emits multiple rays of light at different angles from a common origin. For example, the light that is reflected into the driver"s eyes from the inner and outer air interfaces of the windshield creates the virtual image and a ghost image, respectively, and results in a double image. The windshield comprises laminated safety glass made from two layers of glass that are bonded together with one or more layers of polyvinyl butyral (PVB). Most windshields are not simple flat structures, but include slight curvatures in both the horizontal and vertical dimensions. The ghosting problem is illustrated in Figure 1(a) for standard windshields that have no wedge angle. The green and red lines show the paths of light from the image source, reflecting off the inner and outer windshield–air interfaces, respectively, into the driver"s eye to form the virtual and ghost images. The virtual and ghost images do not overlap, therefore, the image is blurred, as shown on the left of Figure 1(a).

To eliminate this ghosting effect, the angular separation between the virtual and ghost images must be less than the angular resolution of the human eye, which is about 0.2mrad. A PVB interlayer with a small, constant wedge angle is normally used to eliminate the ghost image for a driver at a defined location.2 The optimum wedge angle is dependent on the location of the driver"s eyes, as well as the mounting angle, thickness, and curvature of the windshield.3 This use of a PVB interlayer with a small wedge angle causes the virtual and ghost images to overlap, resulting in a sharp image, as shown on the left of Figure 1(b). A constant wedge angle, however, will only have an optimal effect for a single location of the driver, and taller or shorter drivers will still experience ghosting. To overcome this problem, manufacturers are starting to produce windshields with a wedge angle that varies as a function of the vertical position on the windshield.4, 5