revolution of the tft lcd technology made in china

The introduction of flat panel displays that are fabricated with thin-film-transistor liquid-crystal displays (TFT LCDs) has changed human"s lifestyle very significantly. Traditionally, the revolution of the TFT LCD technology has been presented by the timeline of product introduction. Namely, it first started with audio/video (AV) and notebook applications in the early 1990s, and then began to replace cathode-ray tubes (CRTs) for monitor and TV applications. Certainly, TFT LCDs will continue…Expand

China"s first 8.5-generation TFT-LCD production line was launched in Bengbu, East China"s Anhui province, on June 18, 2019, representing a breakthrough in the production of high-definition LCD screen, Science and Technology Daily reported.

TFT-LCD, or Thin Film Transistor Liquid Crystal Display, is key strategic material of the electronic information display industry. The Gen 8.5 TFT-LCD production line, launched by the Bengbu Glass Industry Design and Research Institute of the China National Building Material Group, will produce high-definition LCD screens of 55 inches, the report said.

According to the Liquid Crystal Branch of the China Optics and Optoelectronics Manufactures Association, the demand for TFT-LCD in the Chinese mainland was about 260 million square meters in 2018, including 233 million square meters" Gen 8.5 TFT-LCD. However, the annual supply of domestically made TFT-LCD is less than 40 million square meters, with all of them Gen 6 or below, which cannot meet the demand in scale and quantity.

The association predicted that China"s market demand for Gen 8.5 TFT-LCD or above will exceed 300 million square meters by 2020, accounting for 49.6 percent of the total global demand.

The production and control precision of Gen 8.5 TFT-LCD is comparable to that of the semiconductor industry, representing a higher level of large-scale manufacturing of modern glass industry.

The institute in Bengbu, with 60 years of expertise in glass, has finally made a breakthrough in the production of Gen 8.5 TFT-LCD, and will provide key raw material guarantee for China"s LCD panel industry after it goes into mass production in September, the report said.

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China is home to various TFT LCD panel manufacturers, all offering exceptional services and high-end products. China remains one of the top sources for TFT LCD panel manufacturing, as they have been producing some of the best quality panels available on the market. Many Chinese technology companies specialize in providing these superior TFT LCDs, and several of them have even managed to make it into the top ten list of China"s leading TFT LCD panel producers. These companies are known for their efficient service, impressive product lineup, reliability, innovative approach to design, and customer service excellence. If you are looking for an excellent China-based supplier for TFT LCD panels, it would be wise to consider one of these top 10 China TFT LCD manufacturers.

China is a leading producer of TFT LCD panels, with industry leaders such as BOE Technology Group Co., Ltd. (BOE) at the forefront of innovation. Founded in 1993, BOE has developed a comprehensive business structure featuring port products and services for information exchange as well as healthcare solutions like its revolutionary MLED technology. In 2021, BOE boasted an impressive 70,000 independent patent applications, and more than 90% of its new patent applications are for invention patents. Additionally, over 35% of those inventions" patents can be found overseas in the United States, Europe, Japan, South Korea, and other countries. China"s TFT LCD panel manufacturers continue developing their technology by innovating on existing models such as LCD screens and LCD panels to provide better solutions for customers worldwide.

China-based Tianma is a highly reputable TFT LCD panel manufacturer with over 30 years of expertise in the display solutions industry. Since 1983, the company has grown to become a trusted China TFT LCD panel provider, and in 1995, it obtained a public listing on China"s Shenzhen Stock Exchange. With tech and production capabilities at the top of their game, Tianma specializes in SLT-LCD, LTPS TFT-LCD, AMOLED, In-cell/On-cell integrated touch technology, Flexible Displays, Force Touch TED Plus, fingerprint recognition under/on-screen and Mini/Micro LED segments. They have set the benchmark for future innovative developments in terms of LCD panels, LCD screens, and more. Offering unbeatable support services around the globe that are coupled with advanced technology makes Tianma a forerunner for China TFT LCD panel manufacturers.

China"s IVO is one of the top 10 China TFT LCD panel manufacturers and has been making a name for itself since 2005. From its Kunsan Jiangsu base, it now employs more than 3000 staff, including 400 dedicated R&D employees. IVO also boasts a G-5 TFT panel production line, and its products are used in a variety of cutting-edge applications: 60% for notebook displays, 23% for smartphones, and 11% for automotive uses. This makes it an important player in the China TFT LCD market as well as gaining great recognition worldwide in the notebook display industry.

With China being one of the leading suppliers in the global TFT LCD market, 4th in the top 10 manufacturers is TCL CSOT. This China TFT LCD panel manufacturer has been expanding its production capacity with continuous developments in technology and gaining a more solid global presence. According to the latest TV shipment stats, China"s CSOT has ranked 3rd in the world for producing TVs and 1st for supplying domestic 6 major brands since 2014. Furthermore, it holds strong places on the world scale when it comes to 55-inch UD product shipments (1st worldwide) and 32-inch UD product shipments (2nd). G6 LTPS-LCD production line is also amongst its highly lauded products, boasting second place in small and medium sizes with the most accelerated growth rate. Focused on independent innovation-driven development, TCLCSOT reinforces its position as China"s leader in TFT LCD screen technology by accumulating 12185 patent applications since 2019.

China"s TFT LCD panel manufacturer, Truly Semiconductor Co., Ltd., was established in 1991 and dedicated to TN-LCD production and became the first China-based CSTN/LCD line producer in 1995. In 2003 they obtained the OLED patents from Kodak, followed by mass production of TFT-LCD modules in 2012 and breakthrough technology in mobile 3D displays. Their 2013 production launch of naked-eye 3D displays for phones and tablet computers solidified their position as China"s top 10 TFT LCD manufacturers. To expand its portfolio further, it invested in Truly (Huizhou) Smart Display Co., Ltd., which specializes in G4.5 AMOLED and TFT displays. Truly sets an example for China"s other TFT LCD panel manufacturers through its sustained 25 years of research and development, innovation, and brand recognition.

Foxconn Technology Group founded China’s TFT LCD panel manufacturing company, Innolux, in 2003. With its headquarters and factory located in Longhua Foxconn Technology Park in Shenzhen and over 14 production bases situated across China like Nanjing, Ningbo and Foshan, Innolux is known for its comprehensive vertical integration that enables cutting-edge display technology research and development. The high quality and reliability of TFT LCD panels manufactured by Innolux have made them available to be used by some of the major global electronics giants like Apple, Lenovo, Hewlett-Packard Panda, Nokia, and Motorola. Furthermore, its amalgamation with Chi Mei Electronics and Tong Bao Optoelectronics in March 2010 has led to a significant improvement in the level of the world plane display industry.

Founded in 2001, China"s top 3 TFT LCD panel manufacturer HKC has come a long way since its inception. The company designs, manufactures, and markets a full range of TFT LCDs from 1 inch to 60 inches with an annual sales amount reaching up to half a billion USD. As it looks for global expansion opportunities, HKC has established branch companies in Russia and India and formed strategic relationships with customers worldwide. In 2010, the China-based firm moved into a new industrial park and is now capable of producing 1 million displays per month. Thanks to advanced technologies and excellent quality control standards, HKC has been praised by its customers both at home and abroad and continues to prove itself as a reliable China TFT LCD panel manufacturer.

Panda is one of China"s top 10 TFT LCD manufacturers, utilizing cutting-edge technology from China Electronics (CEC) to offer a wide range of products such as crystal resonators, thermal-sensitive crystals, ordinary oscillators, voltage-controlled oscillators, and temperature-compensated oscillators. These are used in various applications of TFT LCD screens that can be found in products like LCD TVs, monitors, and laptops. Panda studies customers" requirements with utmost care and provides reliable services and quality products. With the help of its diverse pricing strategy, it assists its clients in finding value for their money across global markets.

China has a flourishing automotive technology industry, and Eagle Tech is one of China"s top ten TFT LCD panel manufacturers. They understand the special requirements of their use environment, such as moisture-proof, dust-proof, anti-glare, high brightness, sun leakage resistance, and temperature resistance, in order to ensure the optimal performance of their displays. Having years of experience in providing Resistive touch screens, PCAP touch screens, and IPS panels make Eagle Tech the trusted electronic display manufacturer for automotive technologies to meet consumer expectations.

China is the leading source of TFT LCD panel manufacturers, and Eagle Tech has been making a name for itself as one of China"s top 10 TFT LCD manufacturers. Not only do they offer quality automotive TFT LCDs in sizes ranging from 3.5" to 21.5", but their products boast excellent durability as well; if you are looking for a reliable China TFT LCD provider that can deliver quality products for your applications, look no further than Eagle Tech.

TFT LCD manufacturing is an incredibly important part of the technology industry, and Century Technology (Shenzhen) Co., Ltd. (CTC) is one of China"s top 10 TFT LCD manufacturers. In addition, CTC invests in global optoelectronics industry personnel who specialize in TFT-LCD research and development, as well as manufacturing display panel products such as laptops, PCs, monitors, and LCD TVs. The production line project was installed during the eleventh five-year plan to position CTC at the forefront of TFT-LCD production lines for the Pearl River Delta region. Looking ahead to late 2008, this ambitious project will be put into action – it is sure to leave a lasting impact on the growth of TFT production globally.

China is the world"s largest producer and exporter of TFT LCD panels, making it a great resource for any company looking to purchase them. China is home to some of the world"s most respected TFT LCD manufacturers, with the top 10 China-based TFT LCD panel manufacturers providing displays that consistently exceed industry requirements. All ten have been commended for their amazing product designs, expertise, and quality standards. Collectively, these companies serve customers all over the world by producing panels that are reliable and high-performance – making China an important resource for businesses seeking out cost-effective TFT LCD panels.

China is quickly becoming the leader in TFT LCD technology. The top 10 China TFT LCD manufacturers are a testament to this, as they provide outstanding quality at competitive prices without sacrificing any of the standards that people have grown to expect from China"s expertise and craftsmanship.

It"s clear that China is fast becoming an unstoppable force when it comes to LCD panel production and innovative screen solutions. With its ability to make efficient panels for various applications, China is respected around the world for its skillful production of TFT LCD panels and screens. Additionally, with these reliable manufacturers trying to ensure maximum customer satisfaction with competitive pricing and high-quality products, China has become a trusted source of LCD screens worldwide.

China has been opened its first thin film transistor liquid crystal display (TFT LCD) production line in the Changchun Digital Science Park in Jilin Province. A joint venture between a Chinese company and a Hong Kong investor, the $160m facility will go into production by the end of the year. It claims to have already signed contracts with local computer and electronics manufacturers for the first two years’ output.

Recently, there is a lot of buzz about whether Apple will choose Mini-LEDover OLED, for the next round of iPads, MacBooks and other products. Regardless of the fascination analyzing current product releases, or one specific consumer-product company, the more significant movement over the last 5~10 years, has been the steep upwards ramp in Micro-LED Startups, IP, investments and acquisitions by: Apple, Facebook, and Google. And from the chip makers themselves such as Intel, Global-Foundries, in Startups such as Luxview, InfiniLED, Plessey, Aledia, Compound Photonics and more.

For an industry that is literally in the business of visualization, the display industry often seems rather opaque, mysterious, and even geo-politically contentious (refer: Foxconn"s LCD Fab in Wisconsin). These articles will cover aspects not well-elaborated in popular analysis, and also provide an update to the material presented 5yrs ago at the Bay-Area SID (Society for Information Displays), on why this technology, is so different, so disruptive, and how it will reach far beyond even the wildest market projections. But for a background on the basics of how & why, vision, the brain and displays work, recommend an easy to digest, and popular, book by Mark Changizi: The Vision Revolution. There are also excellent industry analysts, who cover displays professionally, and in much finer-grain detail, such as Yole Development (thanks to Eric Virey for source graphics) and DSCC (thanks to Ross Young & team for references, and feedback).

Firstly, to be clear: the flat-panel display industry is a semiconductor industry. This is the critical "border", where electrons of digital information, are turned into photons of visual information. And the pixels you see, while reading this article, are driven by transistors - Thin-Film Transistors (TFT) - somewhere between 3 and 12 transistors per pixel, depending on the type of display (OLED needs more than LCD), and the maker. The Transistor, Resistor, Capacitor circuits are built by nano-scale material deposition processes, on a glass substrate (the backplane), via semiconductor manufacturing equipment, from suppliers including US"s Applied Materials, Japan"s Canon Tokki, Korea"s SNU Precision, Wonik IPS and more. Yet it has not attracted the same strategic interest from within the US, as other semiconductor industry segments e.g. processor chips. While there is a drive to increase the number of (existing) semiconductor chip fabs on US soil, the fact is that the US has no significant domestic display manufacturing capability at all, effectivelyzero. And the same is true for most of the technology ingredients comprising the display, such as the film layers, LED’s & OLED and their ingredient materials, and the controller & driver chips - which is dominated entirely by non-US companies you probably never heard of, such as Taiwan Novatek (the 13th largest semi maker, worldwide), Taiwan Himax, Taiwan Parade, and Japan"s Renesas. That is, until one of them has a problem.

So if the geopolitical semiconductor war gets any rougher, you might be wondering, where is this chip (that Biden is holding) going to display it"s output ? On an etch-sketch ? (perhaps the only display device still made in the US ?)

Since more than 40% of our brain is devoted to vision, more than all of the other senses combined, this would seem an important gap. After all, light, color and contrast are the fundamentals of art, literature, civilization, as well as your next Zoom virtual meeting. Of course we need to see the results of the computation of AI, CPU, Memory, GPU, Network, 5G ... processors, appear on some display eventually, right ? So this article also aims to provide some more insights on key factors in the previous transition, what"s going on now, why it"s important, and how it may matter in real-life terms.

Secondly, (and this an easy bet) you’re more likely reading this article on an LCD flat-panel Display, rather than OLED or ePaper. But all 3 have been transformational technologies of the 21st century. Could modern society continue to communicate effectively, presenting a person in front of you from anywhere/anytime, productivity continuing virtually, during a Global Pandemic ? What would it have been like if we were still sharing the 20th century family’s TV ? (recap for millennials: the Cathode Ray Tube TV was a 50 ~ 100 lb, X-Ray-emitting, monster appliance, using electron beam scanning technology from the 1920"s, and with coarse interlaced video rendering designed to save 6MHz (3 Mbit/s by modern standards) of precious radio-frequency bandwidth). Even the 12yr old iPhone 3GS could muster more than that, on a bad day.

As for myself, am writing this article across two of my favorite consumer flat-panel devices: a newer 15” Retina MacBook Pro and an older 17” MacBook Pro. Partly because both are still the best, un-compromised, example of the portability & performance enabled by the Hybrid Graphics technology, a Display & GPU technology, drove across the laptop industry while working at NVIDIA. But mostly because Apple consistently aims for excellence in their displays. Am enjoying a large, bright, 300 “nit” (candela/meter2) LCD screen, an excellent 900~1000:1 contrast ratio, a full DCI-P3 color gamut, and sharp 220 ppi "retina" resolution that renders crisp text and beautiful images. The recurring theme: light, color, contrast.

However, at the 2019, 2020 and 2021 CES, Micro-LED and Mini-LED began appearing across more and more applications (e.g. TV, AR, Monitors, Digital Signage), and demo"s like the Samsung Wall and Sony MicroLED continue to attract the largest, most excited crowds, have ever seen at CES (before it went virtual). Back in 2017, I wrote this article about Micro-LED & Mini-LED"s, talking about potential applications, and specifically about the key challenges to this visual revolution, that PixelDisplay set out to solve: in the color conversion material needed to more economically create Red & Green from the high efficiency Blue. In November 2020, PixelDisplay publicly disclosed details of NanoBright™solution, at the Phosphor & QD Summit, and is now offered for sale on PixelDisplay.com

In the Mini-LED ecosystem, the role of NanoBright is often used the same as per regular white LED"s, which in 2018 PixelDisplay estimated to be worth $750m/yr, but this market is now projected to be worth $5b, for Mini-LED"s overall, by 2025. The color converter can be simply coated on the Mini-LED and surrounding backplane (providing a high efficiency, bright-contrast, High-Dynamic-Range with DCI-P3 wide-color gamut), but there are more interesting benefits e.g. eliminating existing LCD films to make thinner, borderless and more efficient.

But to put this in larger perspective, here"s the role NanoBright™fills in the Micro-LED ecosystem, as described in DSCC"s ( @Guillaume Chansin) excellent LinkedIn article.

But why should this Micro-LED technology be of any broader importance ? Why is it any different than OLED, or LCD ? How is it a disrupting technology ? What difference does it have from any of the other opaque display industry machinations that means it will have significant impact in our lives? It"s a great test to ask: "would my mother care ?".

To start with how it"s different, and how it is disruptive, we need to recap on how we got here on the glass backplane of LCD and OLED. And to fully appreciate the magnitude of the disruption represented by the Micro-LED revolution, we have to also understand the scale of the investment behind the commercializing flat-panel glass, and to the display TFT semiconductor industry.

Am not going to cover the long sordid history of display technologies, nor the detailed lineage of LCD, or OLED. But it is worth noting that both technologies were born in the US, the LCD from RCA, and the OLED from Kodak - and ironically, both pioneering companies are now just brands - non practicing entities. But there are other pioneers, such as UDC, who have persisted, and remain necessary ingredients in the ecosystem (we"ll touch on "why ?" later). But instead, will identify two key elements from the 1990"s, that were the major accelerators flat-panel displays to escape velocity in 2000"s, launched the FPD revolution into orbit, and led to the proliferation of what we enjoy today:

1) TFT follows Square-Rule Growth:To understand the explosion in the economics of producing glass flat panel displays covered in TFT pixels, we can start with the size increases of the glass processing fabrication itself. The term, "Gen" refers to the size generation, the capability of the TFT panel fab, by the dimensions of the glass sheet that it can process, which typically entails creating deposition layers stacked layer-by-layer, to build the TFT pixels - whether OLED or LCD, it starts with TFT pixels on a sheet of glass. In the late 90’s, massive government investments spurred the creation of ever larger display fabrication facilities, with ever larger deposition equipment based on the successful A-Si (amorphous Silicon) process, which grew quickly from Gen 3.5 (0.62 x 0.75m) to Gen 5 (1.1 x 1.3m) to Gen 6 (1.5 x 1.85m) glass substrates, in just a handful of years. Every sheet of glass processed in an LCD production line is cut into smaller panels, making TV’s, Monitors, laptops, tablets and phones.

But unlike Moore’s Law (which doubles transistors every 18months), the glass panel area increase (width x height) results in a faster, power-of-2 square-rule, increase in the number of pixels, and thus the number of TFT transistors. In fact, the number of semiconductor transistors on glass TFT was increasing at 2.5x Moore’s Law, during the last decade. While it took 10 years to go from 5mil transistors in Intel’s Pentium Pro 1995, to 169 mil transistors in the Prescott CPU 2005 – the LCD display industry made the same increase in the number of TFT transistors for 8K resolution, in roughly 5 years (from the PixelDisplay presentation at the 2018 DSCC Future Display Technology Conference).

By early 2000"s, Plasma was beyond hope, the transition from CRT"s was in full-swing, the IBM Thinkpad was a staple of corporate life, and laptops had crossed the 8hr battery-life mark thanks to display efficiency improvements (as we"ll discuss later the display is the key enabler of longer battery-life). The LCD plants were pumping out everything from laptop screens, to LCD monitors, to 60" large-screen LCD TV"s, at lower-and-lower price-points - from fabs based in Japan, then Taiwan, and Korea. By the late 2000"s, the Fab-depreciation (eff. cost of borrowed capital) was the most significant component of the LCD panel prices, and panel makers squeezed the margins out of everyone in the supply chain including films, LED, controller and driver chips. Major winners were the materials suppliers: Corning Inc (the Glass), Merck (the LCD material itself), Nichia (the backlight LED"s), and Canon Tokki & Applied Materials (TFT-glass deposition equipment).

Meanwhile in the US, Intel made a huge bet in 2001, that LCD would not scale, and that LCOS would provide solutions, and enable larger-screen, like the earlier (CRT-based TV) projection displays. But in just 3~4 years, it became clear the LCD square-rule economies were different, ever-larger ever-cheaper LCD panels seemed to be viral, ramping to fill the large-screen TV market. The LCOS & DLP were relegated to the projector market, and Intel exited LCOS in late 2004. It"s worth noting Intel has gradually become more active in the display industry, and Intel Capital has made multiple investments in the Micro-LED partnerships for GaN-on-Si (and we"ll come back to that later).

Outside the US, the display industry has been the target of massive strategic investments for Asia for over 3 decades. Starting with Japan government forcing the collaboration of Sony, Hitachi and Toshiba to create JDI (which made the first iPhone and iPad screens), and the INCJ (a government investment consortium) of Japan, then Korea and Taiwan Governments, and then China. Today this industry is dominated by China, as per the reports from analysts e.g. this one from Display Supply Chain Consultants. The government of China and private investors, aggressively funded the rise of China from sub 10% a decade ago, to owning more than 63% of the world’s display production. By 2017, the Taiwan government had publicly stated they were no longer going to invest in more LCD fabs, and in 2018 the chairman of LG got up in front of the entire company taking a sledge hammer to smash an LCD TV, in a symbolic communication of the company"s shift in focus to the highly profitable OLED (not facing competition from China) - the fate of LCD flat-panels was sealed.

One example of China"s investment in display leadership is Beijing Opto Electronics (BOE). And I have visited BOE’s Gen 6, 8.5, and 10.5 (2.9m x 3.4m) fabs in HeFei and Beijing. This picture below is a panorama I took standing outside one of the older (smaller, older) Gen 8.5 Fab"s from a visit to the BOE facility in HeFei. At the time, they had built a Gen 10 behind it, and building another beside that.

But when you’re outside looking at a factory that is literally over 1.3 kilometer per side, the staggering magnitude of China"s investment in display leadership, is simply breathtaking. The first Gen 10.5 fab located in Sakai Japan, was also Japan"s last one. But at last count there are seven (7) Gen 10.5 fabs in Mainland China, and still more are being built. There is no questioning China’s intent to seize control over the majority of eye-balls, from the source.

2) Inorganic Solid-State gives 4x increase in efficiency: The second important innovation was the In/GaN-based Blue LED. Invented in Japan (ironically, US-based CREE had a blue LED earlier, but failed to productize until much later), from which Nichia made White LED’s, by adding yellow-emitting YAG:Ce inorganic phosphor, they had left over from their CRT phosphor business. It was a cheap trick to synthesize something that looked White, from a psycho-visual hack of using two complementary colors: Blue + Yellow. But in short, the poor color was an acceptable tradeoff for higher-efficiency, smaller size, more robust inorganic solid-state solution. LED backlights quickly transformed the industry from (thicker, bulky, and very fragile) fluorescent tube (CCFL) backlights, into thin/efficient LED backlights, in the early-mid 2000"s. And the lead inventors, including Shuji Nakamora of Nichia, won the 2014 Nobel prize for the work on GaN LED.

This was an important step forward in the story. Originally, the CCFL backlit display was 70~80% of the total power consumption of an idle Laptop. In fact, back in 2001 while at Intel, together with Ying Cui we invented and implemented Intel’s Backlight Modulation Technology (called DPST(tm)) which was like an inverse-High-Dynamic Range, it proportionally increased pixel contrast, in order to allow decreasing the CCFL backlight brightness and provide huge system power-savings. That was the star feature of Intel’s EBL (Extended Battery Life) initiative, saving more system power than other, more publicized, Intel CPU features (e.g. Geyserville aka "SpeedStep"). For me, that was a first introduction to the value and importance of the flat-panel display technology, as the essential ingredient in portable platforms. But LED"s further helped enable the "implosion" of visual-compute portability into sub-8lb / sub-1inch Laptops. And the displays that appeared in Phones and Tablets, were using LED"s that are only 0.4~0.6 mm tall, fitting in the edge of the panel.

Today, LED efficiency is over 200 lm/W (4x the efficiency of older CCFL), but efficiency improvements in processor and memory technology means the display is still typically 50~70% of total system power for phone or laptop, and this is worse for OLED (than LCD) because of how poorly OLED technology handles mostly-white backgrounds (e.g. of browsers, text & productivity applications).

The LED industry has also been a source of massive investment and deeply geopolitical rifts as Japan (e.g. Nichia) vs Korea (e.g. Seoul Semi Conductor) vs Taiwan (e.g. Foxconn/AOT, LiteOn, Epistar) vs China (e.g. CSOT, SanAn). Initially dominated by IP held by Nichia, CREE and Osram, those players now have diminished roles, but it has remained a complex ecosystem.

Tiny efficient LED"s enable 2D-array backlighting on LCD to achieve HDR (High-Dynamic-Range). Higher-end LCD TV"s were the first consumer displays to use LED"s with better R-G Phosphors to create a wider DCI-P3 color gamut. Firstly, arranging the Edge-Backlight LED"s to control 1-Dimensional regions, from along the edge. And then advancing into 2D-array of LED"s, to create active-region backlight. This enabled LCD"s to increase the contrast ratio beyond 1000:1, and peak brightness beyond traditional edge illumination, creating the High-Dynamic Range (HDR) experience first popularized by BrightSide (later acquired by Dolby, to form DolbyVision, and which is now licensed-technology on the iPhone). Today HDR content leverages individual screen-region lighting, to create brighter highlights, and the deeper-blacks to create a more realistic and dynamic experience. In summary, HDR LCD TV with 2D backlight became commercially practical as a result of small (less than 3.0 x 3.0 mm) LED"s with over 220 Lm/W efficiency - 13x more efficient than incandescent bulbs Brightside originally used, which had required huge exotic water cooling solution.

Challenges of the "Crystal Cycle":the size of these glass-processing fab investments is so large, and the equipment CapEx expenditures are so huge, that this leads to massive disconnect between supply and demand, causing large cyclical swings in pricing, which became known as the "Crystal Cycle"

To ride the economies of scale requires increasing the glass handling size, which requires ever larger investments, just as the second of Moore’s Laws predicts. For example, BOE’s invested US$7 billion to make a Gen 10.5 fab. And in an interesting geopolitical twist, after the Taiwan (once a former colony of Japan) government declared they were not investing anymore in the LCD business, Terry Guo (Taiwan Foxconn CEO), acquired a majority of Sharp, and their huge LCD display production lines in Kameyama (which made the innovative IGZO-based LCD panels, which enabled the thinner/more-efficient iPhone 6, and iPad Air), and Japan’s only Gen 10.5 plant in Sakai, which is making 8K TV’s (was spun-off into Sakai Display Corporation). Foxconn was already a large player in the display industry owning Taiwan’s #2 maker, Innolux Optoelectronics. Far beyond merely being “the sport of king’s”, the display industry has been “the sport of nations”.

OLED is doubly challenged: and it has not become progressively cheaper with economies-of-scale as many expected. In LCD only a tiny current is needed to flip a pixel, all of the light is produced from a thin string of backlight LED"s. Whereas in OLED, every pixel is itself a light emitting organic-LED, with many orders of magnitude higher current required at every pixel. The high contrast emissive pixel design of OLED displays provides excellent contrast, but typically requires the use of the more expensive and complex LTPS (low-temperature polycrystalline silicon) process to produce the active TFT driving backplane. LTPS involves a more complex 11-step process, with much higher-temperatures that only a few materials (glass, clear polyamide) can sustain. LTPS requires a high-power excimer laser to anneal the surface, forming the layer of polycrystalline silicon - this is slow, and does not scale well into larger sizes. The OLED fabs have thus been limited to Gen 6 (1.5 x 1.85m) or smaller, in glass size. Even though this is big enough to make a few TV"s, the smaller starting glass size means the cost-curve is sub-optimal, unless partitioned into many smaller panels e.g. the higher-cost has lower impact for smaller smartphone screen. While an oxide deposition process called LTPO (a simpler Oxide process, borrowing from the IGZO process that delivered LCD efficiency improvements in iPhone 6 & iPad Air), offers some hope in the future, there’s another additional challenge.

The complexities of driving a large number of emitters from a thin layer on glass backplane has also meant limits on full-screen brightness, and limited ability to address higher resolutions. A full screen of white does not occur often on a OLED TV, as it does on an Tablet or Laptop, but if you do witness a larger amount of white (as in productivity apps on a Laptop) you"d notice the whole OLED screen goes dimmer, this is done in order to limit the total current across the thin conductor traces that feed the pixels on the glass.

Unlike LCD TFT (which only requires a single transistor and storage capacitor), a typical OLED driving circuit can have 3~6 transistor (and similar number of capacitors) per color i.e. 9~18 transistors per pixel. This driving complexity also limits the net active emitting area of the pixel, versus the inactive driving circuit, also called the "Fill-Ratio". And that"s part of the reason why the Oculus and Samsung Gear VR headsets look like watching everything through a thick fly-screen mesh - the amount of non-emitting "dark-area" per pixel is huge (much larger than LCD). Laying out complex circuits naturally extends the non-emitting pixel-area, horizontally outwards in width & length, that is of course a limitation of thin deposition layers on glass. This limits both the ability to go into finer pitch (>1000ppi and 40Kx16K resolution is the ultimate goal for x-Reality displays), and also to create larger emitters for higher brightness.

Furthermore, the front-plane of an OLED panel requires ultra-precise patterning with emissive organic phosphor materials, with tightly controlled size & depth-tolerances. This has switched from vapor deposition, to inkjet patterning to save some cost, but because of the non-uniformity it is limited in ability to go into very fine pitch, retina-quality displays. But either way, the OLED materials themselves remain very expensive, with Universal Display Corp (UDC) maintaining a tight grip on the materials supply chain, thanks to a portfolio of significant & early IP. The alternatives to UDC patents, such as HF (Hyper fluorescence e.g. KyuLux) or TADFL (thermally activated delayed fluorescence e.g. Cynora) are really 5~10yrs out, and merging QD on OLED aka "QD-OLED (e.g. Nanosys & Samsung) has consistently missed every promised demo/roll-out, and feels more like either a science project, or a ploy for negotiating UDC pricing.

But since OLED breaks-down with age, and even faster with moisture, heat, and higher-energy blue/uv photons (reminder, the “O” in OLED, stands for Organic), the use of glass (or expensive polyamide materials) with low gas & moisture permeability remains a requirement, since lifetime & brightness remain the bigger issues for OLED. In the phone industry, key manufacturers came to embrace OLED since it looks fantastic but wears out - after-all consumers are more motivated to buy a new phone, if it looks noticeably brighter and sharper, than the worn-out 2-year-old one in hand. While higher production costs, aging and burn-in problems of OLED have been acceptable (even desirable) in the phone business, they have hampered the progression of OLED into IT and Automotive applications. And while OLED came with the promise of more freedoms than LCD, in creating foldable and flexible displays, the fact remains: it lasts longer when hermetically encapsulated in glass the best barrier protecting from oxygen and moisture.

While OLED has not enjoyed the same cost-reduction curve, as in the LCD proliferation, the higher-end and visually-satisfying (initial) experience continue to feed hope & investment. Glass TFT has both enabled, and limited OLED"s ability to achieve higher brightness, and higher resolution. There"s frequently news of better OLED solution coming down the research pipeline, and we"ve already touched on the bigger ones (e.g. Hyperfluorescence, Thermally Activated Delayed Fluorescence, Quantum Dot on OLED), but the reality has fallen far short, nor is there anything helping to break-free from the most expensive TFT processes. OLED is very likely to continue to service the small display markets, products that have a shorter life expectancy, and only need a lower-brightness display (e.g. TV"s, which only need 100nits of brightness).

The industry is ripe for disruption from a brighter, more robust inorganic solution, that comes with a better (near-term) ability to reduce cost as it scales.

Unmet needs, in important niche markets: is the essential formula, for the beginning of disruption, as outlined by Clayton Christensen. Who described the formula for disruption as essentially: a niche market (of future importance) with unmet needs, that can afford to adopt a more expensive solution, where that solution has an ability to scale and leverage the niche-win to expand into broader markets, displacing incumbent technologies. Some example display niche markets:Automotive and Smartwatches displays have been over 1,000 nits for some time, but need much more to compete with typical daylight glare.

Autonomous vehicles (e.g. robo-taxis) are on the horizon, but pause for a moment to consider how they will visually communicate to passengers & pedestrians, when no human is present ? No driver to confirm name or usher in passenger, or gesticulate with body language to other less-patient human drivers. The solutions are being developed right now (and PixelDisplay is involved), they of course need to operate in bright daylight, and be colorful & robust as the painted bumper panel or shatter-resistant safety-glass, they"ll be integrated-into.

When the HDR standards were formed, they included a high peak-brightness of 10,000 nits (far beyond wildest dreams of OLED and Quantum Dots), and real-world contrast ratio"s (>10x that available on LCD with edge backlight). And studio-grade content-authoring displays can do well over 4,000 nits, but need constant recalibration to account for non-uniformity from wear, and sometimes replaced after only a year. We can expect this to migrate into more consumer displays over the next 5yrs, and the Gaming/TV/Video/Movie content standards (BluRay-UHD, VESA DisplayHDR and the Hollywood UHD-Alliance) already integrated that support.

These are markets that will pay for a more expensive solution, that can deliver unmet needs of bright, high (HDR) contrast, deep-black and defined shadows, and crisp-rich colors (like OLED), in a thin form-factor, but with higher brightness and longer lifetime (like LED-backlit LCD).

The value of the Flat Panel Display: the industry is worth over $120 billion (3x the value of the GPU market), and is project to grow to well over $200 billion by 2025. Yearly production (rough numbers): over 1.8 billion smartphone panels, 300 million laptop and tablet panels. This thin, complex, glass-stack, in the flat-panel module, still represents the single most expensive component in the phone & tablet (and many laptops also).

In the iPhone BOM, the display has, at times, been more than 2~3x the cost of the SoC (CPU & GPU) and RF BaseBand chips, combined. And in the iPhone 12, the new OLED display is responsible for 35% of the BOM cost increase vs iPhone 11. It should then, be unsurprising that Apple (unlike Intel, NVIDIA, AMD, DELL or any other OEM that I know), has multiple (large) divisions devoted just to display technology - one in each of their business verticals. Staffed with display architects, and engineers refining technologies, sourcing core materials (even the phosphors), creating new designs. Even custom-designing the display controller and driver chips, for the panel makers to insert inside displays made - exclusively for Apple - that are not available to any other panel customers. Perhaps because it is the most critical border of the Visual Information Age, and obviously because it is necessary to control the border to control your future, right ?

In summary,during this pandemic we"re able to adapt and continue our communications visually; collaborating, pitching, working efficiently, and remotely from anywhere; thanks to the internet, wireless connectivity, and the glass flat-panel visual interface. Long Zoom sessions can be taxing, but imagine if this had happened in the 1950"s, 1970"s or 1990"s ? Would our children have been able to engage in school remotely ? Would we have remained as connected, and as productive ?

The technology innovations may have US origins, but the major enablers of the last visual revolution were: a) execution driven by massive investments in manufacturing & commercialization from: Japan, Taiwan, Korea and China in flat-panel display leadership, b) faster than Moore’s Law growth in the economies-of-scale of glass-substrate TFT pixels, and c) the shift to cheaper/smaller/robustsolid-state In/GaN semiconductor LED technology.

Now there’s a another shift happening. With the Micro-LED & Mini-LED generation, there"s a new, and very different, formula. Unlike the past display technologies: Micro-LED are innately decoupled from the glass backplane, and that changes everything.

In the next article,more details of how this visual revolution is progressing, firstly re-igniting LCD 2.0 with Mini-LED"s, and breaking through the glass-barrier with Micro-LED"s, and what displays of the future will look like.

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

There are two main families of OLED: those based on small molecules and those employing polymers. Adding mobile ions to an OLED creates a light-emitting electrochemical cell (LEC) which has a slightly different mode of operation. An OLED display can be driven with a passive-matrix (PMOLED) or active-matrix (AMOLED) control scheme. In the PMOLED scheme, each row and line in the display is controlled sequentially, one by one,thin-film transistor (TFT) backplane to directly access and switch each individual pixel on or off, allowing for higher resolution and larger display sizes.

OLED is fundamentally different from LED which is based on a p-n diode structure. In LEDs doping is used to create p- and n- regions by changing the conductivity of the host semiconductor. OLEDs do not employ a p-n structure. Doping of OLEDs is used to increase radiative efficiency by direct modification of the quantum-mechanical optical recombination rate. Doping is additionally used to determine the wavelength of photon emission.

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

André Bernanose and co-workers at the Nancy-Université in France made the first observations of electroluminescence in organic materials in the early 1950s. They applied high alternating voltages in air to materials such as acridine orange dye, either deposited on or dissolved in cellulose or cellophane thin films. The proposed mechanism was either direct excitation of the dye molecules or excitation of electrons.

In 1960, Martin Pope and some of his co-workers at New York University developed ohmic dark-injecting electrode contacts to organic crystals.work functions) for hole and electron injecting electrode contacts. These contacts are the basis of charge injection in all modern OLED devices. Pope"s group also first observed direct current (DC) electroluminescence under vacuum on a single pure crystal of anthracene and on anthracene crystals doped with tetracene in 1963volts. The proposed mechanism was field-accelerated electron excitation of molecular fluorescence.

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

The first Polymer LED (PLED) to be created was by Roger Partridge at the National Physical Laboratory in the United Kingdom. It used a film of poly(N-vinylcarbazole) up to 2.2 micrometers thick located between two charge-injecting electrodes. The light generated was readily visible in normal lighting conditions though the polymer used had 2 limitations; low conductivity and the difficulty of injecting electrons.

Research into polymer electroluminescence culminated in 1990, with J. H. Burroughes et al. at the Cavendish Laboratory at Cambridge University, UK, reporting a high-efficiency green light-emitting polymer-based device using 100nm thick films of poly(p-phenylene vinylene).plastic electronics and OLED research and device production grew rapidly.et al. at Yamagata University, Japan in 1995, achieved the commercialization of OLED-backlit displays and lighting.

In 1999, Kodak and Sanyo had entered into a partnership to jointly research, develop, and produce OLED displays. They announced the world"s first 2.4-inch active-matrix, full-color OLED display in September the same year.

Manufacturing of small molecule OLEDs was started in 1997 by Pioneer Corporation, followed by TDK in 2001 and Samsung-NEC Mobile Display (SNMD), which later became one of the world"s largest OLED display manufacturers - Samsung Display, in 2002.

The Sony XEL-1, released in 2007, was the first OLED television.Universal Display Corporation, one of the OLED materials companies, holds a number of patents concerning the commercialization of OLEDs that are used by major OLED manufacturers around the world.

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

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

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

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

As electrons and holes are fermions with half integer spin, an exciton may either be in a singlet state or a triplet state depending on how the spins of the electron and hole have been combined. Statistically three triplet excitons will be formed for each singlet exciton. Decay from triplet states (phosphorescence) is spin forbidden, increasing the timescale of the transition and limiting the internal efficiency of fluorescent devices. Phosphorescent organic light-emitting diodes make use of spin–orbit interactions to facilitate intersystem crossing between singlet and triplet states, thus obtaining emission from both singlet and triplet states and improving the internal efficiency.

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

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

Single carrier devices are typically used to study the kinetics and charge transport mechanisms of an organic material and can be useful when trying to study energy transfer processes. As current through the device is composed of only one type of charge carrier, either electrons or holes, recombination does not occur and no light is emitted. For example, electron only devices can be obtained by replacing ITO with a lower work function metal which increases the energy barrier of hole injection. Similarly, hole only devices can be made by using a cathode made solely of aluminium, resulting in an energy barrier too large for efficient electron injection.

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

Organic small-molecule electroluminescent materials have the advantages of a wide variety, easy to purify, and strong chemical modifications. In order to make the luminescent materials to emit light as required, some chromophores or unsaturated groups such as alkene bonds and benzene rings will usually be introduced in the molecular structure design to change the size of the conjugation range of the material, so that the photophysical properties of the material changes. In general, the larger the range of π-electron conjugation system, the longer the wavelength of light emitted by the material. For instance, with the increase of the number of benzene rings, the fluorescence emission peak of benzene, naphthalene, anthracene,anthracenes, biphenyl acetylene aryl derivatives, coumarin derivatives,Ching W. Tang et al.Eastman Kodak. The term OLED traditionally refers specifically to this type of device, though the term SM-OLED is also in use.

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

Because of the structural flexibility of small-molecule electroluminescent materials, thin films can be prepared by vacuum vapor deposition, which is more expensive and of limited use for large-area devices. The vacuum coating system, however, can make the entire process from film growth to OLED device preparation in a controlled and complete operating environment, helping to obtain uniform and stable films, thus ensuring the final fabrication of high-performance OLED devices.However, small molecule organic dyes are prone to fluorescence quenching

Polymer light-emitting diodes (PLED, P-OLED), also light-emitting polymers (LEP), involve an electroluminescent conductive polymer that emits light when connected to an external voltage. They are used as a thin film for full-spectrum colour displays. Polymer OLEDs are quite efficient and require a relatively small amount of power for the amount of light produced.

Vacuum deposition is not a suitable method for forming thin films of polymers. If the polymeric OLED films are made by vacuum vapor deposition, the chain elements will be cut off and the original photophysical properties will be compromised. However, polymers can be processed in solution, and spin coating is a common method of depositing thin polymer films. This method is more suited to forming large-area films than thermal evaporation. No vacuum is required, and the emissive materials can also be applied on the substrate by a technique derived from commercial inkjet printing.Langmuir-Blodgett film.

Typical polymers used in PLED displays include derivatives of poly(p-phenylene vinylene) and polyfluorene. Substitution of side chains onto the polymer backbone may determine the colour of emitted lightring opening metathesis polymerization.

Phosphorescent organic light-emitting diodes use the principle of electrophosphorescence to convert electrical energy in an OLED into light in a highly efficient manner,

The heavy metal atom at the centre of these complexes exhibits strong spin-orbit coupling, facilitating intersystem crossing between singlet and triplet states. By using these phosphorescent materials, both singlet and triplet excitons will be able to decay radiatively, hence improving the internal quantum efficiency of the device compared to a standard OLED where only the singlet states will contribute to emission of light.

Applications of OLEDs in solid state lighting require the achievement of high brightness with good CIE coordinates (for white emission). The use of macromolecular species like polyhedral oligomeric silsesquioxanes (POSS) in conjunction with the use of phosphorescent species such as Ir for printed OLEDs have exhibited brightnesses as high as 10,000cd/m2.

The bottom-emission organic light-emitting diode (BE-OLED) is the architecture that was used in the early-stage AMOLED displays. It had a transparent anode fabricated on a glass substrate, and a shiny reflective cathode. Light is emitted from the transparent anode direction. To reflect all the light towards the anode direction, a relatively thick metal cathode such as aluminum is used. For the anode, high-transparency indium tin oxide (ITO) was a typical choice to emit as much light as possible.thin film transistor (TFT) substrate, and the area from which light can be extracted is limited and the light emission efficiency is reduced.

An alternative configuration is to switch the mode of emission. A reflective anode, and a transparent (or more often semi-transparent) cathode are used so that the light emits from the cathode side, and this configuration is called top-emission OLED (TE-OLED). Unlike BEOLEDs where the anode is made of transparent conductive ITO, this time the cathode needs to be transparent, and the ITO material is not an ideal choice for the cathode because of a damage issue due to the sputtering process.transmittance and high conductivity.

When light waves meet while traveling along the same medium, wave interference occurs. This interference can be constructive or destructive. It is sometimes desirable for several waves of the same frequency to sum up into a wave with higher amplitudes.

Since both electrodes are reflective in TEOLED, light reflections can happen within the diode, and they cause more complex interferences than those in BEOLEDs. In addition to the two-beam interference, there exists a multi-resonance interference between two electrodes. Because the structure of TEOLEDs is similar to that of the Fabry-Perot resonator or laser resonator, which contains two parallel mirrors comparable to the two reflective electrodes),

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

In "white + color filter method," red, green, and blue emissions are obtained from the same white-light LEDs using different color filters.uneven degradation rate of blue pixels vs. red and green pixels. Disadvantages of this method are low color purity and contrast. Also, the filters absorb most of the light waves emitted, requiring the background white light to be relatively strong to compensate for the drop in brightness, and thus the power consumption for such displays can be higher.

Color filters can also be implemented into bottom- and top-emission OLEDs. By adding the corresponding RGB color filters after the semi-transparent cathode, even purer wavelengths of light can be obtained. The use of a microcavity in top-emission OLEDs with color filters also contributes to an increase in the contrast ratio by reducing the reflection of incident ambient light.

Transparent OLEDs use transparent or semi-transparent contacts on both sides of the device to create displays that can be made to be both top and bottom emitting (transparent). TOLEDs can greatly improve contrast, making it much easier to view displays in bright sunlight.Head-up displays, smart windows or augmented reality applications.

Stacked OLEDs use a pixel architecture that stacks the red, green, and blue subpixels on top of one another instead of next to one another, leading to substantial increase in gamut and color depth,

In contrast to a conventional OLED, in which the anode is placed on the substrate, an Inverted OLED uses a bottom cathode that can be connected to the drain end of an n-channel TFT especially for the low cost amorphous silicon TFT b