full active lcd displays factory

This is another story just like those, except this one involves the very screen you’re probably looking at, especially if it’s based on LCD technology.
In the 1970s, a pair of engineers that worked for Westinghouse, T. Peter Brody and Fang-Chen Luo, came to develop the first active-matrix LCD screen. Brody, born in Hungary, had gained an interest in the fledgling technology of thin film transistors, an experimental technology that had come to be seen as a potential avenue for visually displaying content in a more compact form than a cathode-ray tube.
“It has been apparent for some time that a solid-state flat panel display is conceptually achievable,” the patent filing stated. “Efforts to utilize silicon technology to this end are limited by the size limitation problems of the silicon wafer, which negates achievement of large area displays.”
But it was the starting point of the technology that stuck. By the mid-1990s, active-matrix displays that relied on color became the norm in laptops, thanks to their combination of vivid color and thinness. But despite the concept coming from an American company’s R&D department and improved by other American R&D departments, nearly all panels were developed by Japanese manufacturers even at the beginning of their mainstream use cases.
In fact, Westinghouse’s efforts with the flat-panel LCD display ended way back in the 1970s, as did similar efforts at other large U.S. companies. “Both large corporations and venture capital-backed start-ups have quit the field, usually after hitting production difficulties,” authors Richard Florida and David Browdy wrote.

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EarthLCD is a division of Earth Computer Technologies, Inc. originally founded in 1984. A full line of products plus custom engineered solutions are available. We source LCD displays direct from major manufacturers world wide allowing for a cost advantage over our competitors. EarthLCD offer’s the world’s widest variety of LCD’s in fully integrated solutions for OEM supply chain requirements.
EarthLCD targets industries such as Point Of Sale, Industrial Automation, Security, Hospitality, Kiosks, Home Automation, OEM, Gaming, Banking, Service, Test Equipment and Monitoring, Embedded Systems, Automotive, and many other applications.

We have thousands of standard products that are in stock and available from our Seattle, WA and Hong Kong warehouses to support fast product development and preproduction without MOQ. The stock covers TN, STN LCD display panels, COB, COG character LCD display, graphic LCD display, PMOLED, AMOLED display, TFT display, IPS display, high brightness and transflective, blanview sunlight readable display, super high contrast ratio display, lightning fast response displays, efficient low power consumption display, extreme temperature range display, HMI display, HDMI display, Raspberry Pi Display, Arduino display, embedded display, capacitive touch screen, LED backlight etc. Customers can easily purchase samples directly from our website to avoid time delays with setting up accounts and credit terms and shipping within 24 hours.
Many of our customers require customized OEM display solutions. With over two decades of experience, we apply our understanding of available display solutions to meet our customer’s requirements and assist from project concept to mass production. Using your ideas and requirements as a foundation, we work side by side with you to develop ideas/concepts into drawings, build prototypes and to final production seamlessly. In order to meet the fast changing world, we can provide the fastest turnaround in the industry, it takes only 3-4 weeks to produce LCD panels samples and 4-6 weeks for LCD display module, TFT LCD, IPS LCD display, and touch screen samples. The production time is only 4-5 weeks for LCD panels and 5-8 weeks for LCD display module, TFT LCD, IPS LCD display, and touch screen.

TFT is an LCD Technology which adds a thin-film transistor at each pixel to supply common voltages to all elements. This voltage improves video content frame rates. Displays are predominantly utilizing color filter layers and white LED backlighting.
OLED Displays are emissive displays and do not utilize liquid crystal. Each pixel is emissive with light. Passive OLED displays multiplex power and logic through the IC. Active OLED displays add a transistor at each pixel to supply power directly to the pixels and the IC only performs logical functions.

Established in 2007, Raystar has built its reputation by offering advanced products in PMOLED display and modules as well as in FSTN / STN LCD Display Module, COG LCD, TFT LCD Display.

When working with a 20×4 character LCD, you might be surprised to see the controller set to 2-line mode: Write_To_LCD(COMMAND,0x38); //SET 2 LINE,5*8 FONT Why would a 4-line LCD’s controller be set to 2-line mode? It has to do with the way the LCD glass is laid out. Essentially the display is the right and … Read more FAQ: Why does the initialization code for a 20×4 LCD specify 2-line mode?
What is involved in ISO certification (and annual recertification) and what does it mean for a company to be ISO certified? This post takes a deeper look at everything involved in ISO certification for our LCD electronics-based company.
Confused about the differences between TFTs, LCDs, and OLEDs? What Do They Stand For? How Do They Work? TFT displays are also known as an “Active Matrix TFT LCD module” and have an array of thin film transistors fabricated on the glass that makes the LCD. There is one of these transistors for each pixel on the … Read more FAQ: What is the Difference Between a TFT, LCD, and OLED?
Sherman, set the wayback machine to 1985: We are going to take a look at the original HD44780 Data Sheet. Some time back, we wrote about the legendary HD44780 controller, to which the modern character LCD industry owes much of its existence. Having been in the business of designing embedded electronics for some time, we … Read more A Look Back in Tech History: The HD44780 Controller Data Sheet
Did you know that ePaper modules emulate ink used for paper? Check out the meaning of the glossary term electrophoresis and how it relates to ePaper module displays. Need ePaper for Your Project? For assistance in determining what ePaper module is the best one for your application, please contact our knowledgeable and friendly support staff by email, phone, or … Read more A Quick ePaper Primer
Modern Character LCD display modules have been possible since 1987 when Hitachi introduced the HD44780 LCD controller. Since then, Hitachi no longer manufactures this integrated circuit (IC), but modern LCD controller ICs make it a point to be HD44780-compatible. Controller Compatibility The character LCD display modules offered by Crystalfontz America Inc. are no exception to … Read more The Legendary HD44780 Controller
Confused about the differences (and similarities) between OLEDs, PMOLEDs, and AMOLEDs? Quick Version: OLED stands for Organic Light Emitting Diode. PMOLED is Passive Matrix OLED — Passive Matrix Organic Light Emitting Diode. AMOLED is Active Matrix OLED. An Active Matrix OLED uses a TFT (Thin Film Transistor) transistor-per-pixel architecture. Learn More To find out more … Read more What is the Difference Between OLED, PMOLED, and AMOLED?

When working with a 20×4 character LCD, you might be surprised to see the controller set to 2-line mode: Write_To_LCD(COMMAND,0x38); //SET 2 LINE,5*8 FONT Why would a 4-line LCD’s controller be set to 2-line mode? It has to do with the way the LCD glass is laid out. Essentially the display is the right and … Read more FAQ: Why does the initialization code for a 20×4 LCD specify 2-line mode?
What is involved in ISO certification (and annual recertification) and what does it mean for a company to be ISO certified? This post takes a deeper look at everything involved in ISO certification for our LCD electronics-based company.
Confused about the differences between TFTs, LCDs, and OLEDs? What Do They Stand For? How Do They Work? TFT displays are also known as an “Active Matrix TFT LCD module” and have an array of thin film transistors fabricated on the glass that makes the LCD. There is one of these transistors for each pixel on the … Read more FAQ: What is the Difference Between a TFT, LCD, and OLED?
Sherman, set the wayback machine to 1985: We are going to take a look at the original HD44780 Data Sheet. Some time back, we wrote about the legendary HD44780 controller, to which the modern character LCD industry owes much of its existence. Having been in the business of designing embedded electronics for some time, we … Read more A Look Back in Tech History: The HD44780 Controller Data Sheet
Did you know that ePaper modules emulate ink used for paper? Check out the meaning of the glossary term electrophoresis and how it relates to ePaper module displays. Need ePaper for Your Project? For assistance in determining what ePaper module is the best one for your application, please contact our knowledgeable and friendly support staff by email, phone, or … Read more A Quick ePaper Primer
Modern Character LCD display modules have been possible since 1987 when Hitachi introduced the HD44780 LCD controller. Since then, Hitachi no longer manufactures this integrated circuit (IC), but modern LCD controller ICs make it a point to be HD44780-compatible. Controller Compatibility The character LCD display modules offered by Crystalfontz America Inc. are no exception to … Read more The Legendary HD44780 Controller
Confused about the differences (and similarities) between OLEDs, PMOLEDs, and AMOLEDs? Quick Version: OLED stands for Organic Light Emitting Diode. PMOLED is Passive Matrix OLED — Passive Matrix Organic Light Emitting Diode. AMOLED is Active Matrix OLED. An Active Matrix OLED uses a TFT (Thin Film Transistor) transistor-per-pixel architecture. Learn More To find out more … Read more What is the Difference Between OLED, PMOLED, and AMOLED?

As your Kyocera Display distributor and solution provider, Edge can help you choose the appropriate LCD display for your project and supply you with compatible accessories or enhancements such as a controller board or inverter. We supply Kyocera Display"s full line of LCD displays including active TFT LCDs, passive displays, and OLEDs.
Kyocera is a leading manufacturer of LCD products, focused on total solutions for the industrial and automotive markets. Kyocera offers high performance TFT display products, applied LTPS TFT array technology, and high performance passive displays.
Kyocera Display products feature superior optical performance, such as high transmittance, high contrast, high brightness, and high reliability in both standard TFT-LCDs and full custom products.

Planar® CarbonLight™ VX Series is comprised of carbon fiber-framed indoor LED video wall and floor displays with exceptional on-camera visual properties and deployment versatility, available in 1.9 and 2.6mm pixel pitch (wall) and 2.6mm (floor).
From cinema content to motion-based digital art, Planar® Luxe MicroLED Displays offer a way to enrich distinctive spaces. HDR support and superior dynamic range create vibrant, high-resolution canvases for creative expression and entertainment. Leading-edge MicroLED technology, design adaptability and the slimmest profiles ensure they seamlessly integrate with architectural elements and complement interior décor.
From cinema content to motion-based digital art, Planar® Luxe Displays offer a way to enrich distinctive spaces. These professional-grade displays provide vibrant, high-resolution canvases for creative expression and entertainment. Leading-edge technology, design adaptability and the slimmest profiles ensure they seamlessly integrate with architectural elements and complement interior decor.
From cinema content to motion-based digital art, Planar® Luxe MicroLED Displays offer a way to enrich distinctive spaces. HDR support and superior dynamic range create vibrant, high-resolution canvases for creative expression and entertainment. Leading-edge MicroLED technology, design adaptability and the slimmest profiles ensure they seamlessly integrate with architectural elements and complement interior décor.
Planar® CarbonLight™ VX Series is comprised of carbon fiber-framed indoor LED video wall and floor displays with exceptional on-camera visual properties and deployment versatility, available in 1.9 and 2.6mm pixel pitch (wall) and 2.6mm (floor).
Carbon fiber-framed indoor LED video wall and floor displays with exceptional on-camera visual properties and deployment versatility for various installations including virtual production and extended reality.
a line of extreme and ultra-narrow bezel LCD displays that provides a video wall solution for demanding requirements of 24x7 mission-critical applications and high ambient light environments
Since 1983, Planar display solutions have benefitted countless organizations in every application. Planar displays are usually front and center, dutifully delivering the visual experiences and critical information customers need, with proven technology that is built to withstand the rigors of constant use.

From their discovery in 1888 to their first application within displays in the 1960s, liquid crystals have become a mainstream material choice with many impactful applications in the world of electronics.
As the key component behind liquid crystal displays (LCD), these materials change light polarization to create vibrant, high-resolution images on digital screens. The growth of LCD technology has helped propel the larger display panel market enormously, with industry valuation projected to reach $178.20 billion by 2026.
A prolific variety of LCD types has been developed to best meet their exact use-cases and end-environments. Displays may be optimized for power consumption, contrast ratio, color reproduction, optimal viewing angle, temperature range, cost, and more.
Passive Matrix LCDs are addressed with common and segment electrodes. A pixel or an icon is formed at the intersection where a common and a segment electrode overlap. Common electrodes are addressed one-at-a-time in a sequence. Segment electrodes are addressed simultaneously with the information corresponding to all pixels or icons connected to the current common electrode. This method is referred to as multiplexing.
Passive Matrix LCDs offer a cost advantage (both parts and tooling) and are highly customizable. The counterpart to Passive Matrix displays are Active Matrix displays.
Active-Matrix LCDs were developed to overcome some of the limitations of Passive Matrix LCDs – namely resolution, color, and size. Within an Active-Matrix LCD, an “active element” is added to each pixel location (the intersection between a horizontal row and vertical column electrode). These active elements, which can be diodes or transistors, create a threshold and allow control of the optical response of the liquid crystal structure to the applied voltage. Transistors are used as switches to charge a capacitor, which then provides the voltage to the pixel. Whenever a row is turned on, one at a time, all transistor switches in that row are closed and all pixel capacitors are charged with the appropriate voltage. The capacitor then keeps the voltage applied to the pixel after the row is switched off until the next refresh cycle.
Furthermore, the processes used for manufacturing Active-Matrix LCDs can create much finer details on the electrode structure. This allows splitting each pixel in three sub-pixels with different color. This together with the better voltage control allows full color displays.
The transistor switches used in Active Matrix Displays must not protrude significantly above the surface of the display substrates lest they might interfere with a uniform liquid crystal layer thickness. They must be implemented in thin films of suitable materials. Hence, the name Thin Film Transistors (TFT). While AM and TFT have a different meaning, they are often used interchangeably to indicate a higher performance display.
Currently the most common Electronics Display Technology on the market is LCD technology and among LCD technologies, TFT display technology is the most widely used across consumer applications (laptops, tablets, TVs, Mobile phones, etc.) as well as many industrial, automotive, and medical applications.
As the first commercially successful LCD technology, Passive Matrix Twisted Nematic (TN) LCDs use a 90° twist of the nematic LC fluid between two polarizers to display information. The twist of the LC fluid either blocks light from passing through the LCD cell or allows light to pass, depending on the applied voltage. The applied voltage changes the twisted nematic orientation into an orientation that does not change the polarization of tight. This is called the TN effect.
TN displays can be normally white (NW) when they use two orthogonal liner polarizers or normally black (NB) when parallel linear polarizers are used. ‘Normally’ refers to what happens when no voltage is applied.
Initially, Passive TN LCDs were used in segmented, icon, or character displays where an image element was turned “on” and “off” depending on how the fluid was driven. Improvements were made along the way to address the limited viewing angle of TN technology, which can suffer from contrast loss or even inversion at shallow angles.
It can be advantageous to twist the director of the nematic phase a bit more than 90 degrees, but less than 180 degrees. Displays like this are a subset of TN displays and are sometimes caller Hyper Twisted Nematic Displays.
The numbers of rows or icons that can be addressed in a TN display without Active Matrix addressing is very limited. This is related to how strongly the liquid crystal responds to the applied voltage. Twisting the LC nematic fluid more than 180 degrees (typically between 210 and 270 degrees) causes the display to require a much smaller voltage difference between on and off pixels. This in turn allows addressing of many more rows without an active matrix. Displays with a twist between 210 and 270 degrees are called Super Twisted Nematic displays.
The higher display resolution of STN displays comes at a price. The optical effect is no longer neutrally black and white as in a TN display. Rather these displays are naturally yellow and black or blue and white. The color can be somewhat compensated with colored polarizers, but that comes at the expense of brightness and contrast.
The color in STN displays is caused by birefringence. Adding the same birefringence in the opposite direction can compensate for the effect. Initially this was done by stacking two STN displays on top of each other. This is referred to as Double STN or DSTN, but this is of course thicker and more expensive.
The birefringence of an STN display can be approximated with a stretched transparent plastic film. Adding such a film to an STN display instead of the 2nd STN display is a lot more attractive and has almost the same performance. This is referred to as a Film Compensated STN display (FSTN, or sometimes if two films are used as FFSTN).
FSTN displays are used commonly in consumer, medical and industrial display applications that require low cost and do not need high resolution images or full color.
Another development to the TN display was to use the same concept as in FSTN displays on TN displays. However, the film cannot just be a stretched polymer. Instead, a twisted liquid crystal structure is made and polymerized into a film that is used as a compensation film for TN displays. As this method mostly improves the display characteristics at shallow viewing angles while preserving the excellent performance in straight on viewing, this technology is called Wide View Twisted Nematic (WVTN).
The above display technologies have liquid crystal molecules that are aligned nearly parallel to the display surface with more or less twisting when going from one substrate to the other. In VA (also called VAN) displays, the liquid crystal molecules are aligned vertically with respect to the display surface. Applying a voltage causes the molecules to lay flat, with or without twist.
The advantage of this arrangement is a very dark black state with very little light leakage. This allows making displays with a black mask and colored icons or symbols. These displays look like color displays with brilliant colors, however each image element or icon can only have its assigned color or black.
Due to the ability in AM displays to address one row while the other rows are isolated, the demands on the electro-optical performance of the Liquid Crystal Configuration are less stringent. In principle, all the above mentioned configurations can be used in AM displays. In practice, TN, and WVTN are frequently used as well as some versions of VA technology described below. (MVA, AIFF-MVA, PVA, ASV).
The advantage of these technologies is a much wider and more symmetrical viewing angle along with the elimination of the contrast inversion (or color shift) seen in TN TFT LCDs when viewed from various angles. IPS and FFS displays also are less sensitive to pressure, which is a big advantage in touchscreen displays.
Here, each color sub-pixel is further divided into zones (called domains) having a different direction of the molecular movement when voltage is applied. Again, the purpose is a much wider and more symmetric viewing performance and the elimination of color shifts and contrast inversion at shallow angles. MVA technology achieves that with carefully designed protrusions on the inside surfaces of the display, while PVA uses fine patterning of the electrodes on both substrates.
The integrated circuit is a patterned piece of silicon or other type of semiconducting material. A modern IC contains millions or even billions of tiny transistors. Their tiny size allows for the fabrication of smaller, faster, more efficient, and less expensive electronic circuits. The driver chips addressing electronics displays are ICs.
Legacy LCDs normally have the driver ICs (integrated circuit) mounted on a printed circuit board (PCBA) which consists of a flat sheet of insulating material used to mount and connect the driver IC and electronic periphery to the LCD. PCBs can be a single-sided, double-sided or multi-layer.
Low Voltage Differential Signaling (LVDS) is an interface to the display, not a display technology itself. This technology is not specific to displays, as it’s used in many other applications as well. It’s a high-speed signal that provides some noise immunity for the display. It also allows for longer distances compared to parallel interfaces.

Glass substrate with ITO electrodes. The shapes of these electrodes will determine the shapes that will appear when the LCD is switched ON. Vertical ridges etched on the surface are smooth.
A liquid-crystal display (LCD) is a flat-panel display or other electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers. Liquid crystals do not emit light directlybacklight or reflector to produce images in color or monochrome.seven-segment displays, as in a digital clock, are all good examples of devices with these displays. They use the same basic technology, except that arbitrary images are made from a matrix of small pixels, while other displays have larger elements. LCDs can either be normally on (positive) or off (negative), depending on the polarizer arrangement. For example, a character positive LCD with a backlight will have black lettering on a background that is the color of the backlight, and a character negative LCD will have a black background with the letters being of the same color as the backlight. Optical filters are added to white on blue LCDs to give them their characteristic appearance.
LCDs are used in a wide range of applications, including LCD televisions, computer monitors, instrument panels, aircraft cockpit displays, and indoor and outdoor signage. Small LCD screens are common in LCD projectors and portable consumer devices such as digital cameras, watches, calculators, and mobile telephones, including smartphones. LCD screens have replaced heavy, bulky and less energy-efficient cathode-ray tube (CRT) displays in nearly all applications. The phosphors used in CRTs make them vulnerable to image burn-in when a static image is displayed on a screen for a long time, e.g., the table frame for an airline flight schedule on an indoor sign. LCDs do not have this weakness, but are still susceptible to image persistence.
Each pixel of an LCD typically consists of a layer of molecules aligned between two transparent electrodes, often made of Indium-Tin oxide (ITO) and two polarizing filters (parallel and perpendicular polarizers), the axes of transmission of which are (in most of the cases) perpendicular to each other. Without the liquid crystal between the polarizing filters, light passing through the first filter would be blocked by the second (crossed) polarizer. Before an electric field is applied, the orientation of the liquid-crystal molecules is determined by the alignment at the surfaces of electrodes. In a twisted nematic (TN) device, the surface alignment directions at the two electrodes are perpendicular to each other, and so the molecules arrange themselves in a helical structure, or twist. This induces the rotation of the polarization of the incident light, and the device appears gray. If the applied voltage is large enough, the liquid crystal molecules in the center of the layer are almost completely untwisted and the polarization of the incident light is not rotated as it passes through the liquid crystal layer. This light will then be mainly polarized perpendicular to the second filter, and thus be blocked and the pixel will appear black. By controlling the voltage applied across the liquid crystal layer in each pixel, light can be allowed to pass through in varying amounts thus constituting different levels of gray.
The chemical formula of the liquid crystals used in LCDs may vary. Formulas may be patented.Sharp Corporation. The patent that covered that specific mixture expired.
Most color LCD systems use the same technique, with color filters used to generate red, green, and blue subpixels. The LCD color filters are made with a photolithography process on large glass sheets that are later glued with other glass sheets containing a TFT array, spacers and liquid crystal, creating several color LCDs that are then cut from one another and laminated with polarizer sheets. Red, green, blue and black photoresists (resists) are used. All resists contain a finely ground powdered pigment, with particles being just 40 nanometers across. The black resist is the first to be applied; this will create a black grid (known in the industry as a black matrix) that will separate red, green and blue subpixels from one another, increasing contrast ratios and preventing light from leaking from one subpixel onto other surrounding subpixels.Super-twisted nematic LCD, where the variable twist between tighter-spaced plates causes a varying double refraction birefringence, thus changing the hue.
LCD in a Texas Instruments calculator with top polarizer removed from device and placed on top, such that the top and bottom polarizers are perpendicular. As a result, the colors are inverted.
The optical effect of a TN device in the voltage-on state is far less dependent on variations in the device thickness than that in the voltage-off state. Because of this, TN displays with low information content and no backlighting are usually operated between crossed polarizers such that they appear bright with no voltage (the eye is much more sensitive to variations in the dark state than the bright state). As most of 2010-era LCDs are used in television sets, monitors and smartphones, they have high-resolution matrix arrays of pixels to display arbitrary images using backlighting with a dark background. When no image is displayed, different arrangements are used. For this purpose, TN LCDs are operated between parallel polarizers, whereas IPS LCDs feature crossed polarizers. In many applications IPS LCDs have replaced TN LCDs, particularly in smartphones. Both the liquid crystal material and the alignment layer material contain ionic compounds. If an electric field of one particular polarity is applied for a long period of time, this ionic material is attracted to the surfaces and degrades the device performance. This is avoided either by applying an alternating current or by reversing the polarity of the electric field as the device is addressed (the response of the liquid crystal layer is identical, regardless of the polarity of the applied field).
Displays for a small number of individual digits or fixed symbols (as in digital watches and pocket calculators) can be implemented with independent electrodes for each segment.alphanumeric or variable graphics displays are usually implemented with pixels arranged as a matrix consisting of electrically connected rows on one side of the LC layer and columns on the other side, which makes it possible to address each pixel at the intersections. The general method of matrix addressing consists of sequentially addressing one side of the matrix, for example by selecting the rows one-by-one and applying the picture information on the other side at the columns row-by-row. For details on the various matrix addressing schemes see passive-matrix and active-matrix addressed LCDs.
LCDs are manufactured in cleanrooms borrowing techniques from semiconductor manufacturing and using large sheets of glass whose size has increased over time. Several displays are manufactured at the same time, and then cut from the sheet of glass, also known as the mother glass or LCD glass substrate. The increase in size allows more displays or larger displays to be made, just like with increasing wafer sizes in semiconductor manufacturing. The glass sizes are as follows:
Until Gen 8, manufacturers would not agree on a single mother glass size and as a result, different manufacturers would use slightly different glass sizes for the same generation. Some manufacturers have adopted Gen 8.6 mother glass sheets which are only slightly larger than Gen 8.5, allowing for more 50 and 58 inch LCDs to be made per mother glass, specially 58 inch LCDs, in which case 6 can be produced on a Gen 8.6 mother glass vs only 3 on a Gen 8.5 mother glass, significantly reducing waste.AGC Inc., Corning Inc., and Nippon Electric Glass.
The origins and the complex history of liquid-crystal displays from the perspective of an insider during the early days were described by Joseph A. Castellano in Liquid Gold: The Story of Liquid Crystal Displays and the Creation of an Industry.IEEE History Center.Peter J. Wild, can be found at the Engineering and Technology History Wiki.
In 1922, Georges Friedel described the structure and properties of liquid crystals and classified them in three types (nematics, smectics and cholesterics). In 1927, Vsevolod Frederiks devised the electrically switched light valve, called the Fréedericksz transition, the essential effect of all LCD technology. In 1936, the Marconi Wireless Telegraph company patented the first practical application of the technology, "The Liquid Crystal Light Valve". In 1962, the first major English language publication Molecular Structure and Properties of Liquid Crystals was published by Dr. George W. Gray.RCA found that liquid crystals had some interesting electro-optic characteristics and he realized an electro-optical effect by generating stripe-patterns in a thin layer of liquid crystal material by the application of a voltage. This effect is based on an electro-hydrodynamic instability forming what are now called "Williams domains" inside the liquid crystal.
In the late 1960s, pioneering work on liquid crystals was undertaken by the UK"s Royal Radar Establishment at Malvern, England. The team at RRE supported ongoing work by George William Gray and his team at the University of Hull who ultimately discovered the cyanobiphenyl liquid crystals, which had correct stability and temperature properties for application in LCDs.
The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968.dynamic scattering mode (DSM) LCD that used standard discrete MOSFETs.
On December 4, 1970, the twisted nematic field effect (TN) in liquid crystals was filed for patent by Hoffmann-LaRoche in Switzerland, (Swiss patent No. 532 261) with Wolfgang Helfrich and Martin Schadt (then working for the Central Research Laboratories) listed as inventors.Brown, Boveri & Cie, its joint venture partner at that time, which produced TN displays for wristwatches and other applications during the 1970s for the international markets including the Japanese electronics industry, which soon produced the first digital quartz wristwatches with TN-LCDs and numerous other products. James Fergason, while working with Sardari Arora and Alfred Saupe at Kent State University Liquid Crystal Institute, filed an identical patent in the United States on April 22, 1971.ILIXCO (now LXD Incorporated), produced LCDs based on the TN-effect, which soon superseded the poor-quality DSM types due to improvements of lower operating voltages and lower power consumption. Tetsuro Hama and Izuhiko Nishimura of Seiko received a US patent dated February 1971, for an electronic wristwatch incorporating a TN-LCD.
In 1972, the concept of the active-matrix thin-film transistor (TFT) liquid-crystal display panel was prototyped in the United States by T. Peter Brody"s team at Westinghouse, in Pittsburgh, Pennsylvania.Westinghouse Research Laboratories demonstrated the first thin-film-transistor liquid-crystal display (TFT LCD).high-resolution and high-quality electronic visual display devices use TFT-based active matrix displays.active-matrix liquid-crystal display (AM LCD) in 1974, and then Brody coined the term "active matrix" in 1975.
In 1972 North American Rockwell Microelectronics Corp introduced the use of DSM LCDs for calculators for marketing by Lloyds Electronics Inc, though these required an internal light source for illumination.Sharp Corporation followed with DSM LCDs for pocket-sized calculators in 1973Seiko and its first 6-digit TN-LCD quartz wristwatch, and Casio"s "Casiotron". Color LCDs based on Guest-Host interaction were invented by a team at RCA in 1968.TFT LCDs similar to the prototypes developed by a Westinghouse team in 1972 were patented in 1976 by a team at Sharp consisting of Fumiaki Funada, Masataka Matsuura, and Tomio Wada,
In 1983, researchers at Brown, Boveri & Cie (BBC) Research Center, Switzerland, invented the passive matrix-addressed LCDs. H. Amstutz et al. were listed as inventors in the corresponding patent applications filed in Switzerland on July 7, 1983, and October 28, 1983. Patents were granted in Switzerland CH 665491, Europe EP 0131216,
The first color LCD televisions were developed as handheld televisions in Japan. In 1980, Hattori Seiko"s R&D group began development on color LCD pocket televisions.Seiko Epson released the first LCD television, the Epson TV Watch, a wristwatch equipped with a small active-matrix LCD television.dot matrix TN-LCD in 1983.Citizen Watch,TFT LCD.computer monitors and LCD televisions.3LCD projection technology in the 1980s, and licensed it for use in projectors in 1988.compact, full-color LCD projector.
In 1990, under different titles, inventors conceived electro optical effects as alternatives to twisted nematic field effect LCDs (TN- and STN- LCDs). One approach was to use interdigital electrodes on one glass substrate only to produce an electric field essentially parallel to the glass substrates.Germany by Guenter Baur et al. and patented in various countries.Hitachi work out various practical details of the IPS technology to interconnect the thin-film transistor array as a matrix and to avoid undesirable stray fields in between pixels.
Hitachi also improved the viewing angle dependence further by optimizing the shape of the electrodes (Super IPS). NEC and Hitachi become early manufacturers of active-matrix addressed LCDs based on the IPS technology. This is a milestone for implementing large-screen LCDs having acceptable visual performance for flat-panel computer monitors and television screens. In 1996, Samsung developed the optical patterning technique that enables multi-domain LCD. Multi-domain and In Plane Switching subsequently remain the dominant LCD designs through 2006.South Korea and Taiwan,
In 2007 the image quality of LCD televisions surpassed the image quality of cathode-ray-tube-based (CRT) TVs.LCD TVs were projected to account 50% of the 200 million TVs to be shipped globally in 2006, according to Displaybank.Toshiba announced 2560 × 1600 pixels on a 6.1-inch (155 mm) LCD panel, suitable for use in a tablet computer,
In 2016, Panasonic developed IPS LCDs with a contrast ratio of 1,000,000:1, rivaling OLEDs. This technology was later put into mass production as dual layer, dual panel or LMCL (Light Modulating Cell Layer) LCDs. The technology uses 2 liquid crystal layers instead of one, and may be used along with a mini-LED backlight and quantum dot sheets.
Since LCDs produce no light of their own, they require external light to produce a visible image.backlight. Active-matrix LCDs are almost always backlit.Transflective LCDs combine the features of a backlit transmissive display and a reflective display.
CCFL: The LCD panel is lit either by two cold cathode fluorescent lamps placed at opposite edges of the display or an array of parallel CCFLs behind larger displays. A diffuser (made of PMMA acrylic plastic, also known as a wave or light guide/guiding plateinverter to convert whatever DC voltage the device uses (usually 5 or 12 V) to ≈1000 V needed to light a CCFL.
EL-WLED: The LCD panel is lit by a row of white LEDs placed at one or more edges of the screen. A light diffuser (light guide plate, LGP) is then used to spread the light evenly across the whole display, similarly to edge-lit CCFL LCD backlights. The diffuser is made out of either PMMA plastic or special glass, PMMA is used in most cases because it is rugged, while special glass is used when the thickness of the LCD is of primary concern, because it doesn"t expand as much when heated or exposed to moisture, which allows LCDs to be just 5mm thick. Quantum dots may be placed on top of the diffuser as a quantum dot enhancement film (QDEF, in which case they need a layer to be protected from heat and humidity) or on the color filter of the LCD, replacing the resists that are normally used.
WLED array: The LCD panel is lit by a full array of white LEDs placed behind a diffuser behind the panel. LCDs that use this implementation will usually have the ability to dim or completely turn off the LEDs in the dark areas of the image being displayed, effectively increasing the contrast ratio of the display. The precision with which this can be done will depend on the number of dimming zones of the display. The more dimming zones, the more precise the dimming, with less obvious blooming artifacts which are visible as dark grey patches surrounded by the unlit areas of the LCD. As of 2012, this design gets most of its use from upscale, larger-screen LCD televisions.
RGB-LED array: Similar to the WLED array, except the panel is lit by a full array of RGB LEDs. While displays lit with white LEDs usually have a poorer color gamut than CCFL lit displays, panels lit with RGB LEDs have very wide color gamuts. This implementation is most popular on professional graphics editing LCDs. As of 2012, LCDs in this category usually cost more than $1000. As of 2016 the cost of this category has drastically reduced and such LCD televisions obtained same price levels as the former 28" (71 cm) CRT based categories.
Monochrome LEDs: such as red, green, yellow or blue LEDs are used in the small passive monochrome LCDs typically used in clocks, watches and small appliances.
Mini-LED: Backlighting with Mini-LEDs can support over a thousand of Full-area Local Area Dimming (FLAD) zones. This allows deeper blacks and higher contrast ratio.
Today, most LCD screens are being designed with an LED backlight instead of the traditional CCFL backlight, while that backlight is dynamically controlled with the video information (dynamic backlight control). The combination with the dynamic backlight control, invented by Philips researchers Douglas Stanton, Martinus Stroomer and Adrianus de Vaan, simultaneously increases the dynamic range of the display system (also marketed as HDR, high dynamic range television or FLAD, full-area local area dimming).
The LCD backlight systems are made highly efficient by applying optical films such as prismatic structure (prism sheet) to gain the light into the desired viewer directions and reflective polarizing films that recycle the polarized light that was formerly absorbed by the first polarizer of the LCD (invented by Philips researchers Adrianus de Vaan and Paulus Schaareman),
A pink elastomeric connector mating an LCD panel to circuit board traces, shown next to a centimeter-scale ruler. The conductive and insulating layers in the black stripe are very small.
A standard television receiver screen, a modern LCD panel, has over six million pixels, and they are all individually powered by a wire network embedded in the screen. The fine wires, or pathways, form a grid with vertical wires across the whole screen on one side of the screen and horizontal wires across the whole screen on the other side of the screen. To this grid each pixel has a positive connection on one side and a negative connection on the other side. So the total amount of wires needed for a 1080p display is 3 x 1920 going vertically and 1080 going horizontally for a total of 6840 wires horizontally and vertically. That"s three for red, green and blue and 1920 columns of pixels for each color for a total of 5760 wires going vertically and 1080 rows of wires going horizontally. For a panel that is 28.8 inches (73 centimeters) wide, that means a wire density of 200 wires per inch along the horizontal edge.
The LCD panel is powered by LCD drivers that are carefully matched up with the edge of the LCD panel at the factory level. The drivers may be installed using several methods, the most common of which are COG (Chip-On-Glass) and TAB (Tape-automated bonding) These same principles apply also for smartphone screens that are much smaller than TV screens.anisotropic conductive film or, for lower densities, elastomeric connectors.
Monochrome and later color passive-matrix LCDs were standard in most early laptops (although a few used plasma displaysGame Boyactive-matrix became standard on all laptops. The commercially unsuccessful Macintosh Portable (released in 1989) was one of the first to use an active-matrix display (though still monochrome). Passive-matrix LCDs are still used in the 2010s for applications less demanding than laptop computers and TVs, such as inexpensive calculators. In particular, these are used on portable devices where less information content needs to be displayed, lowest power consumption (no backlight) and low cost are desired or readability in direct sunlight is needed.
A comparison between a blank passive-matrix display (top) and a blank active-matrix display (bottom). A passive-matrix display can be identified when the blank background is more grey in appearance than the crisper active-matrix display, fog appears on all edges of the screen, and while pictures appear to be fading on the screen.
Displays having a passive-matrix structure are employing Crosstalk between activated and non-activated pixels has to be handled properly by keeping the RMS voltage of non-activated pixels below the threshold voltage as discovered by Peter J. Wild in 1972,
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.
Twisted nematic displays contain liquid crystals that twist and untwist at varying degrees to allow light to pass through. When no voltage is applied to a TN liquid crystal cell, polarized light passes through the 90-degrees twisted LC layer. In proportion to the voltage applied, the liquid crystals untwist changing the polarization and blocking the light"s path. By properly adjusting the level of the voltage almost any gray level or transmission can be achieved.
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.
Usually no refresh-rate flicker, because the LCD pixels hold their state between refreshes (which are usually done at 200 Hz or faster, regardless of the input refresh rate).
No theoretical resolution limit. When multiple LCD panels are used together to create a single canvas, each additional panel increases the total resolution of the display, which is commonly called stacked resolution.
LCDs can be made transparent and flexible, but they cannot emit light without a backlight like OLED and microLED, which are other technologies that can also be made flexible and transparent.
As an inherently digital device, the LCD can natively display digital data from a DVI or HDMI connection without requiring conversion to analog. Some LCD panels have native fiber optic inputs in addition to DVI and HDMI.
Limited viewing angle in some older or cheaper monitors, causing color, saturation, contrast and brightness to vary with user position, even within the intended viewing angle. Special films can be used to increase the viewing angles of LCDs.
As of 2012, most implementations of LCD backlighting use pulse-width modulation (PWM) to dim the display,CRT monitor at 85 Hz refresh rate would (this is because the entire screen is strobing on and off rather than a CRT"s phosphor sustained dot which continually scans across the display, leaving some part of the display always lit), causing severe eye-strain for some people.LED-backlit monitors, because the LEDs switch on and off faster than a CCFL lamp.
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.
Subject to burn-in effect, although the cause differs from CRT and the effect may not be permanent, a static image can cause burn-in in a matter of hours in badly designed displays.
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.
Several different families of liquid crystals are used in liquid crystal displays. The molecules used have to be anisotropic, and to exhibit mutual attraction. Polarizable rod-shaped molecules (biphenyls, terphenyls, etc.) are common. A common form is a pair of aromatic benzene rings, with a nonpolar moiety (pentyl, heptyl, octyl, or alkyl oxy group) on one end and polar (nitrile, halogen) on the other. Sometimes the benzene rings are separated with an acetylene group, ethylene, CH=N, CH=NO, N=N, N=NO, or ester group. In practice, eutectic mixtures of several chemicals are used, to achieve wider temperature operating range (−10..+60 °C for low-end and −20..+100 °C for high-performance displays). For example, the E7 mixture is composed of three biphenyls and one terphenyl: 39 wt.% of 4"-pentyl[1,1"-biphenyl]-4-carbonitrile (nematic range 24..35 °C), 36 wt.% of 4"-heptyl[1,1"-biphenyl]-4-carbonitrile (nematic range 30..43 °C), 16 wt.% of 4"-octoxy[1,1"-biphenyl]-4-carbonitrile (nematic range 54..80 °C), and 9 wt.% of 4-pentyl[1,1":4",1-terphenyl]-4-carbonitrile (nematic range 131..240 °C).
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".
Castellano, Joseph A (2005). Liquid Gold: The Story of Liquid Crystal Displays and the Creation of an Industry. World Scientific Publishing. ISBN 978-981-238-956-5.
Liquid Gold: The Story of Liquid Crystal Displays and the Creation of an Industry, Joseph A. Castellano, 2005 World Scientific Publishing Co. Pte. Ltd., ISBN 981-238-956-3.
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.
Competing display technologies for the best image performance; A.J.S.M. de Vaan; Journal of the society of information displays, Volume 15, Issue 9 September 2007 Pages 657–666; http://onlinelibrary.wi
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