tft lcd color monitor reviews made in china

The monitoring system is consisted of extra-large high resolution TFT-LCD screen (4.3 inch) and Two Cameras. One of the most powerful flagship devices for your precious and dearest.

Monitor is built with 4.3-inch high resolution TFT-LCD screen (64K colors) and human-engineered exterior. Short cuts are allocated on both side in order to your fastest operation, just like a handheld gaming device. The 16:9 wide screen, is completely same resolution as popular portable gaming screen. Parents are always enjoying their life with best vision experience.

We consider your convenience before building the monitoring system. One-key-fast-operation is always our priority. You don’t need to spend too much time on understanding this professional device until further functions. Shortcuts may cover top features you would like to experience. Control your video/audio, talk balk to the camera very easily.

It is important to have two cameras for two rooms, because of two babies. Two cameras are paired before the monitoring system comes to you. Switch to your desired camera when they are paired to the monitor simultaneously. The monitor could also switch to each camera periodically (10s), automatically, by enabling AUTO-SCAN option in your handheld.

Light ray may vary lots of properties when transmitting through kinds of media and process, air, glass, water, optical-to-electrical converting, etc. We ensure the light ray is well received to the CMOS sensor, which is built-in the camera. An anti-reflective coated lens could avoid precious’ light information lost too much. Meanwhile, processor within the camera makes optical compensation, recovering the real image transmitting to monitor.

The monitor may turn screen off to sleep to save its own energy, but snooze. However, camera is always listening and watching what is happening at your precious. It could hear a sudden voice, like crying or shouting, and then send a signal to the monitor to wake up.

Don’t need going to your precious frequently for the room temperature, it is always shown on your monitor screen. Indicated number goes blinking when temperature turning out of normal range. Fahrenheit and Celsius units are available (press and hold VIDEO ON/OFF for 3 seconds).

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 1888,Friedrich Reinitzer (1858–1927) discovered the liquid crystalline nature of cholesterol extracted from carrots (that is, two melting points and generation of colors) and published his findings at a meeting of the Vienna Chemical Society on May 3, 1888 (F. Reinitzer: Beiträge zur Kenntniss des Cholesterins, Monatshefte für Chemie (Wien) 9, 421–441 (1888)).Otto Lehmann published his work "Flüssige Kristalle" (Liquid Crystals). In 1911, Charles Mauguin first experimented with liquid crystals confined between plates in thin layers.

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.

The MOSFET (metal-oxide-semiconductor field-effect transistor) was invented by Mohamed M. Atalla and Dawon Kahng at Bell Labs in 1959, and presented in 1960.Paul K. Weimer at RCA developed the thin-film transistor (TFT) in 1962.

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.

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.

Most of the new M+ technology was employed on 4K TV sets which led to a controversy after tests showed that the addition of a white sub pixel replacing the traditional RGB structure would reduce the resolution by around 25%. This means that a 4K TV cannot display the full UHD TV standard. The media and internet users later called this "RGBW" TVs because of the white sub pixel. Although LG Display has developed this technology for use in notebook display, outdoor and smartphones, it became more popular in the TV market because the announced 4K UHD resolution but still being incapable of achieving true UHD resolution defined by the CTA as 3840x2160 active pixels with 8-bit color. This negatively impacts the rendering of text, making it a bit fuzzier, which is especially noticeable when a TV is used as a PC monitor.

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.

Low power consumption. Depending on the set display brightness and content being displayed, the older CCFT backlit models typically use less than half of the power a CRT monitor of the same size viewing area would use, and the modern LED backlit models typically use 10–25% of the power a CRT monitor would use.

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.

Limited viewing angle in some older or cheaper monitors, causing color, saturation, contrast and brightness to vary with user position, even within the intended viewing angle.

Uneven backlighting in some monitors (more common in IPS-types and older TNs), causing brightness distortion, especially toward the edges ("backlight bleed").

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.

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".

Rong-Jer Lee; Jr-Cheng Fan; Tzong-Shing Cheng; Jung-Lung Wu (March 10, 1999). "Pigment-dispersed color resist with high resolution for advanced color filter application". Proceedings of 5th Asian Symposium on Information Display. ASID "99 (IEEE Cat. No.99EX291). pp. 359–363. doi:10.1109/ASID.1999.762781. ISBN 957-97347-9-8. S2CID 137460486 – via IEEE Xplore.

Kawamoto, H. (2012). "The Inventors of TFT Active-Matrix LCD Receive the 2011 IEEE Nishizawa Medal". Journal of Display Technology. 8 (1): 3–4. Bibcode:2012JDisT...8....3K. doi:10.1109/JDT.2011.2177740. ISSN 1551-319X.

Explanation of CCFL backlighting details, "Design News — Features — How to Backlight an LCD" Archived January 2, 2014, at the Wayback Machine, Randy Frank, Retrieved January 2013.

LCD Television Power Draw Trends from 2003 to 2015; B. Urban and K. Roth; Fraunhofer USA Center for Sustainable Energy Systems; Final Report to the Consumer Technology Association; May 2017; http://www.cta.tech/cta/media/policyImages/policyPDFs/Fraunhofer-LCD-TV-Power-Draw-Trends-FINAL.pdf Archived August 1, 2017, at the Wayback Machine

New Cholesteric Colour Filters for Reflective LCDs; C. Doornkamp; R. T. Wegh; J. Lub; SID Symposium Digest of Technical Papers; Volume 32, Issue 1 June 2001; Pages 456–459; http://onlinelibrary.wiley.com/doi/10.1889/1.1831895/full

Printable Reflective Color Filter Arrays from Cholesteric Reactive Mesogen Nanoposts; M.E. Sousa and G.P. Crawford; Society of Information Displays; SID digest, Volume 36, Issue 1; May 2005; Pages 706–709; http://onlinelibrary.wiley.com/doi/10.1889/1.2036540/full#references

K. H. Lee; H. Y. Kim; K. H. Park; S. J. Jang; I. C. Park & J. Y. Lee (June 2006). "A Novel Outdoor Readability of Portable TFT-LCD with AFFS Technology". SID Symposium Digest of Technical Papers. 37 (1): 1079–1082. doi:10.1889/1.2433159. S2CID 129569963.

Jack H. Park (January 15, 2015). "Cut and Run: Taiwan-controlled LCD Panel Maker in Danger of Shutdown without Further Investment". www.businesskorea.co.kr. Archived from the original on May 12, 2015. Retrieved April 23, 2015.

NXP Semiconductors (October 21, 2011). "UM10764 Vertical Alignment (VA) displays and NXP LCD drivers" (PDF). Archived from the original (PDF) on March 14, 2014. Retrieved September 4, 2014.

"Samsung to Offer "Zero-PIXEL-DEFECT" Warranty for LCD Monitors". Forbes. December 30, 2004. Archived from the original on August 20, 2007. Retrieved September 3, 2007.

"Display (LCD) replacement for defective pixels – ThinkPad". Lenovo. June 25, 2007. Archived from the original on December 31, 2006. Retrieved July 13, 2007.

M. d"Zmura, T. P. Janice Shen, Wei Wu, Homer Chen, and Marius Vassiliou (1998), "Contrast Gain Control for Color Image Quality," IS&T/SPIE Conference on Human Vision and Electronic Imaging III, San Jose, California, January 1998, SPIE Vol. 3299, 194-201.

Explanation of why pulse width modulated backlighting is used, and its side-effects, "Pulse Width Modulation on LCD monitors", TFT Central. Retrieved June 2012.

An enlightened user requests Dell to improve their LCD backlights, "Request to Dell for higher backlight PWM frequency" Archived December 13, 2012, at the Wayback Machine, Dell Support Community. Retrieved June 2012.

Oleg Artamonov (January 23, 2007). "Contemporary LCD Monitor Parameters: Objective and Subjective Analysis". X-bit labs. Archived from the original on May 16, 2008. Retrieved May 17, 2008.

We strive for excellence, service the customers", hopes to become the best cooperation team and dominator enterprise for personnel, suppliers and customers, realizes value share and continuous promotion for Tft Monitor Is, Portable Lcd Screen, Customize Tft Lcd Module, Module Tft,Small Touch Screen. We cordially welcome customers from at home and abroad to join us and cooperate with us to enjoy a better future. The product will supply to all over the world, such as Europe, America, Australia,Durban, Mexico,Singapore, Uruguay.Our products are widely recognized and trusted by users and can meet continuously developing economic and social needs. We welcome new and old customers from all walks of life to contact us for future business relationships and achieving mutual success!

Innovation, excellent and reliability are the core values of our firm. These principles today more than ever form the basis of our success as an internationally active mid-size corporation for 7 Inch Tft Display Price, Large Character Lcd Display, High Brightness Tn Lcd Module, Panel Led Lcd,Lcd Display Module. We invites you and your enterprise to thrive together with us and share a bright future in global market. The product will supply to all over the world, such as Europe, America, Australia,Puerto Rico, Belgium,Australia, Romania.With top quality products, great after-sales service and warranty policy, we win trust from many overseas partner, many good feedbacks witnessed our factory"s growth. With full confidence and strength, welcome customers to contact and visit us for future relationship.

* Rewards 3% back excludes taxes and shipping. Rewards are issued to your online Dell Rewards Account (available via your Dell.com My Account) typically within 30 business days after your order’s ship date. Rewards expire in 90 days (except where prohibited by law). “Current rewards balance” amount may not reflect the most recent transactions. Check Dell.com My Account for your most up-to-date reward balance. Total rewards earned may not exceed $2,000 within a 3-month period. Outlet purchases do not qualify for rewards. Expedited Delivery not available on certain TVs, monitors, batteries and adapters, and is available in Continental (except Alaska) U.S. only. Other exceptions apply. Not valid for resellers and/or online auctions. Offers and rewards subject to change without notice, not combinable with all other offers. See Dell.com/rewardsfaq. $50 in bonus rewards for Dell Rewards Members who open a new Dell Preferred Account (DPA), or Dell Business Credit (DBC) account on or after 8/10/2022. $50 bonus rewards typically issued within 30 business days after DPA or DBC open date.

*Expedited Delivery: * Expedited Delivery not available on certain TVs, monitors, batteries and adapters, and is available in Continental (except Alaska) U.S. only. Other exceptions apply. Not valid for resellers and/or online auctions. Offers subject to change, not combinable with all other offers. See Dell.com/rewardsfaq.

5K monitors. Take it up a notch with the LG UltraFine monitor, boasting an immersive 27-inch display with 5120 x 2880 resolution and 218 ppi that lets you experience the beauty of a MacBook or MacBook Pro on a large 5K screen. Add to that an unbelievable color spectrum of P3 99% and you’ll be editing and enjoying high-res photos like never before. Too much for you to handle? There’s an impressive 21.5-inch Mac-friendly 4K version as well.

21:9 Curved UltraWide monitors. These high-performance, feature-packed monitors are quite the multitaskers themselves, featuring UltraWide 21:9 resolution, 4-Screen Split, Mac-compatibility, Dual Linkup and stunning Full HD 1080p. They’re the perfect solutions for designers, photographers, gamers and other professionals who need more room for their big ideas.

IPS monitors. Boasting true-to-life colors, IPS computer monitors lessen color loss and help keep colors consistent at virtually any angle. The LED backlighting delivers deep black levels and rich colors for an amazing contrast and color detail.

Gaming monitors. Get panoramic multitasking and immersive gaming with features like a 144Hz refresh rate—the highest of any gaming monitor—plus a response time of less than 1ms (1/1000 of a second) in Motion 240 Mode. It’s the ideal monitor for real-time strategy and first-person shooters. Dynamic Action Sync® lets you catch every single moment in real time, while LG’s Black Stabilizer® brightens dark scenes so the enemy can’t hide. Get true-to-life color and brilliant clarity from virtually every angle.

TV monitors. Get Full HD 1080p entertainment from the TV, as well as your computer. With features like a built-in digital tuner and Dolby Surround sound, LG TV monitors can bring your favorite movies and TV shows to life, along with your favorite online content and games.

Discover the latest innovations in performance and technology with LG computer monitors—and choose one that fits your world. From 4K, IPS and gaming monitors, to TV, LED, UltraWide, UltraFine options and more. It’s time to make life good.

In recent years, China and other countries have invested heavily in the research and manufacturing capacity of display technology. Meanwhile, different display technology scenarios, ranging from traditional LCD (liquid crystal display) to rapidly expanding OLED (organic light-emitting diode) and emerging QLED (quantum-dot light-emitting diode), are competing for market dominance. Amidst the trivium strife, OLED, backed by technology leader Apple"s decision to use OLED for its iPhone X, seems to have a better position, yet QLED, despite still having technological obstacles to overcome, has displayed potential advantage in color quality, lower production costs and longer life.

Zhao: We all know display technologies are very important. Currently, there are OLED, QLED and traditional LCD technologies competing with each other. What are their differences and specific advantages? Shall we start from OLED?

Huang: OLED has developed very quickly in recent years. It is better to compare it with traditional LCD if we want to have a clear understanding of its characteristics. In terms of structure, LCD largely consists of three parts: backlight, TFT backplane and cell, or liquid section for display. Different from LCD, OLED lights directly with electricity. Thus, it does not need backlight, but it still needs the TFT backplane to control where to light. Because it is free from backlight, OLED has a thinner body, higher response time, higher color contrast and lower power consumption. Potentially, it may even have a cost advantage over LCD. The biggest breakthrough is its flexible display, which seems very hard to achieve for LCD.

Liao: Actually, there were/are many different types of display technologies, such as CRT (cathode ray tube), PDP (plasma display panel), LCD, LCOS (liquid crystals on silicon), laser display, LED (light-emitting diodes), SED (surface-conduction electron-emitter display), FED (filed emission display), OLED, QLED and Micro LED. From display technology lifespan point of view, Micro LED and QLED may be considered as in the introduction phase, OLED is in the growth phase, LCD for both computer and TV is in the maturity phase, but LCD for cellphone is in the decline phase, PDP and CRT are in the elimination phase. Now, LCD products are still dominating the display market while OLED is penetrating the market. As just mentioned by Dr Huang, OLED indeed has some advantages over LCD.

Huang: Despite the apparent technological advantages of OLED over LCD, it is not straightforward for OLED to replace LCD. For example, although both OLED and LCD use the TFT backplane, the OLED’s TFT is much more difficult to be made than that of the voltage-driven LCD because OLED is current-driven. Generally speaking, problems for mass production of display technology can be divided into three categories, namely scientific problems, engineering problems and production problems. The ways and cycles to solve these three kinds of problems are different.

At present, LCD has been relatively mature, while OLED is still in the early stage of industrial explosion. For OLED, there are still many urgent problems to be solved, especially production problems that need to be solved step by step in the process of mass production line. In addition, the capital threshold for both LCD and OLED are very high. Compared with the early development of LCD many years ago, the advancing pace of OLED has been quicker.While in the short term, OLED can hardly compete with LCD in large size screen, how about that people may change their use habit to give up large screen?

Liao: I want to supplement some data. According to the consulting firm HIS Markit, in 2018, the global market value for OLED products will be US$38.5 billion. But in 2020, it will reach US$67 billion, with an average compound annual growth rate of 46%. Another prediction estimates that OLED accounts for 33% of the display market sales, with the remaining 67% by LCD in 2018. But OLED’s market share could reach to 54% in 2020.

Huang: While different sources may have different prediction, the advantage of OLED over LCD in small and medium-sized display screen is clear. In small-sized screen, such as smart watch and smart phone, the penetration rate of OLED is roughly 20% to 30%, which represents certain competitiveness. For large size screen, such as TV, the advancement of OLED [against LCD] may need more time.

Xu: LCD was first proposed in 1968. During its development process, the technology has gradually overcome its own shortcomings and defeated other technologies. What are its remaining flaws? It is widely recognized that LCD is very hard to be made flexible. In addition, LCD does not emit light, so a back light is needed. The trend for display technologies is of course towards lighter and thinner (screen).

But currently, LCD is very mature and economic. It far surpasses OLED, and its picture quality and display contrast do not lag behind. Currently, LCD technology"s main target is head-mounted display (HMD), which means we must work on display resolution. In addition, OLED currently is only appropriate for medium and small-sized screens, but large screen has to rely on LCD. This is why the industry remains investing in the 10.5th generation production line (of LCD).

Xu: While deeply impacted by OLED’s super thin and flexible display, we also need to analyse the insufficiency of OLED. With lighting material being organic, its display life might be shorter. LCD can easily be used for 100 000 hours. The other defense effort by LCD is to develop flexible screen to counterattack the flexible display of OLED. But it is true that big worries exist in LCD industry.

LCD industry can also try other (counterattacking) strategies. We are advantageous in large-sized screen, but how about six or seven years later? While in the short term, OLED can hardly compete with LCD in large size screen, how about that people may change their use habit to give up large screen? People may not watch TV and only takes portable screens.

Some experts working at a market survey institute CCID (China Center for Information Industry Development) predicted that in five to six years, OLED will be very influential in small and medium-sized screen. Similarly, a top executive of BOE Technology said that after five to six years, OLED will counterweigh or even surpass LCD in smaller sizes, but to catch up with LCD, it may need 10 to 15 years.

Xu: Besides LCD, Micro LED (Micro Light-Emitting Diode Display) has evolved for many years, though people"s real attention to the display option was not aroused until May 2014 when Apple acquired US-based Micro LED developer LuxVue Technology. It is expected that Micro LED will be used on wearable digital devices to improve battery"s life and screen brightness.

Micro LED, also called mLED or μLED, is a new display technology. Using a so-called mass transfer technology, Micro LED displays consist of arrays of microscopic LEDs forming the individual pixel elements. It can offer better contrast, response times, very high resolution and energy efficiency. Compared with OLED, it has higher lightening efficiency and longer life span, but its flexible display is inferior to OLED. Compared with LCD, Micro LED has better contrast, response times and energy efficiency. It is widely considered appropriate for wearables, AR/VR, auto display and mini-projector.

However, Micro LED still has some technological bottlenecks in epitaxy, mass transfer, driving circuit, full colorization, and monitoring and repairing. It also has a very high manufacturing cost. In short term, it cannot compete traditional LCD. But as a new generation of display technology after LCD and OLED, Micro LED has received wide attentions and it should enjoy fast commercialization in the coming three to five years.

Peng: It comes to quantum dot. First, QLED TV on market today is a misleading concept. Quantum dots are a class of semiconductor nanocrystals, whose emission wavelength can be continuously tuned because of the so-called quantum confinement effect. Because they are inorganic crystals, quantum dots in display devices are very stable. Also, due to their single crystalline nature, emission color of quantum dots can be extremely pure, which dictates the color quality of display devices.

Interestingly, quantum dots as light-emitting materials are related to both OLED and LCD. The so-called QLED TVs on market are actually quantum-dot enhanced LCD TVs, which use quantum dots to replace the green and red phosphors in LCD’s backlight unit. By doing so, LCD displays greatly improve their color purity, picture quality and potentially energy consumption. The working mechanisms of quantum dots in these enhanced LCD displays is their photoluminescence.

For its relationship with OLED, quantum-dot light-emitting diode (QLED) can in certain sense be considered as electroluminescence devices by replacing the organic light-emitting materials in OLED. Though QLED and OLED have nearly identical structure, they also have noticeable differences. Similar to LCD with quantum-dot backlighting unit, color gamut of QLED is much wider than that of OLED and it is more stable than OLED.

Another big difference between OLED and QLED is their production technology. OLED relies on a high-precision technique called vacuum evaporation with high-resolution mask. QLED cannot be produced in this way because quantum dots as inorganic nanocrystals are very difficult to be vaporized. If QLED is commercially produced, it has to be printed and processed with solution-based technology. You can consider this as a weakness, since the printing electronics at present is far less precision than the vacuum-based technology. However, solution-based processing can also be considered as an advantage, because if the production problem is overcome, it costs much less than the vacuum-based technology applied for OLED. Without considering TFT, investment into an OLED production line often costs tens of billions of yuan but investment for QLED could be just 90–95% less.

Peng: Good questions. Ligand chemistry of quantum dots has developed quickly in the past two to three years. Colloidal stability of inorganic nanocrystals should be said of being solved. We reported in 2016 that one gram of quantum dots can be stably dispersed in one milliliter of organic solution, which is certainly sufficient for printing technology. For the second question, several companies have been able to mass produce quantum dots. At present, all these production volume is built for fabrication of the backlighting units for LCD. It is believed that all high-end TVs from Samsung in 2017 are all LCD TVs with quantum-dot backlighting units. In addition, Nanosys in the United States is also producing quantum dots for LCD TVs. NajingTech at Hangzhou, China demonstrate production capacity to support the Chinese TV makers. To my knowledge, NajingTech is establishing a production line for 10 million sets of color TVs with quantum-dot backlighting units annually.China"s current demands cannot be fully satisfied from the foreign companies. It is also necessary to fulfill the demands of domestic market. That is why China must develop its OLED production capability.

Huang: The importance of China"s LCD manufacturing is now globally high. Compared with the early stage of LCD development, China"s status in OLED has been dramatically improved. When developing LCD, China has adopted the pattern of introduction-absorption-renovation. Now for OLED, we have a much higher percentage of independent innovation.

units for LCD and electroluminescence in QLED. For the photoluminescence applications, the key is quantum-dot materials. China has noticeable advantages in quantum-dot materials.

Huang: When OLED was compared with LCD in the past, lots of advantages of OLED were highlighted, such as high color gamut, high contrast and high response speed and so on. But above advantages would be difficult to be the overwhelming superiority to make the consumers to choose replacement.

It seems to be possible that the flexible display will eventually lead a killer advantage. I think QLED will also face similar situation. What is its real advantage if it is compared with OLED or LCD? For QLED, it seem