tft lcd versus led future made in china

TFT LCD is a mature technology. OLED is a relatively new display technology, being used in more and more applications. As for Micro LED, it is a new generation technology with very promising future. Followings are the pros and cons of each display technology.

TFT Liquid Crystal Display is widely used these days. Since LCD itself doesn"t emit light. TFT LCD relies on white LED backlight to show content. This is an explanation of how TFT LCD works.

Relatively lower contrast：Light needs to pass through LCD glasses, liquid crystal layer, polarizers and color filters. Over 90% is lost. Also, LCD can not display pure black.

Organic Light-Emitting Diode is built from an electro-luminescent layer that contains organic compounds, which emit light in response to an electric current. There are two types of OLED, Passive Matrix OLED (PMOLED) and Active Matrix OLED (AMOLED). These driving methods are similar to LCD"s. PMOLED is controlled sequentially using a matrix addressing scheme, m + n control signals are required to address a m x n display. AMOLED uses a TFT backplane that can switch individual pixels on and off.

Low power consumption and flexible: OLED doesn"t rely on backlight and consumes less power. OLED is essentially created on plastic film. It is bendable and easy to process.

High contrast and vivid color: OLED emits light itself, can produce very bright image with beautiful color. And because OLED can be turned off, it can produce true black.

Stroboscopic effect: most OLED screen uses PWM dimming technology. Some people who are easy perceive stroboscopic frequency may have sore eyes and tears.

​Micro LED, sometimes called μLED is made up of tiny LED, measure less than 100μm. Another way of looking at this is that MicroLEDs are simply traditional LEDs shrunk down and placed into an array.

Replacing organic material with inorganic GaN material eliminates the need of polarizing and encapsulation layer, found in OLED. Micro LED is smaller and thinner, consumes less power.

China has become the world"s largest LCD panel manufacturing base and is investing in a complete Mini/Micro-LED industry chain. Li Leiguang, JW Insights" chief analyst of the display industry, shared this information at a Mini/Micro-LED industry forum held in Shenzhen in late October.

China had long depended on imports of IC and display screens in the manufacturing of display products. IC and display screens are the two pillar sectors of the ICT Industry. The trend has been changing. With the continuous increase of high-generation production lines and capacity of domestic panel manufacturers and the gradual closure of LCD production lines by South Korean manufacturers, China"s LCD panel market share has increased year by year.

In 2020, China achieved a trade surplus in LCD panels for the first time. Meanwhile, the TFT-LCD has become a mainstream choice in the display panel industry after nearly 30 years of development.

JW Insights data shows that China has invested a total of RMB1.2 trillion($187.56 billion) in TFT-LCD and AMOLED panel production lines; Some 50 TFT-LCD and AMOLED panel production lines have been built, with 197 million m2/year TFT-LCD production capacity, 8.9 million m2/year AMOLED production capacity.

China"s LCD production capacity accounted for 50% of the global production capacity in 2020, becoming the world"s largest LCD panel production center; It will reach more than 75% of the world"s total by 2025.

China"s mainland is currently the only region that maintains continuous growth in LCD panel production capacity. With Japanese and South Korean manufacturers gradually withdrawing from the LCD panel, China is becoming the dominant player.

Chinese domestic display panel manufacturers are also embracing new display technologies such as Mini LED, Mirco LED, OLED and Micro OLED (silicon-based OLED), which are in an explosive market growth phase.

Chinese screen manufacturers plan to invest nearly RMB 30 billion($4.7 billion) in silicon-based OLED products lines, with more than 15 planned production lines and the total production capacity equivalent to 95 million units 1-inch screen, according to JW Insights statistics.

Meanwhile, China is leading the world in Micro LED research and development. Chinese players have actively invested in the Mini/Micro-LED, geared up for a new round of capacity ramps. The total investments in this field have amounted to RMB100 billion($15.6 billion), expected to accelerate Mini/Micro LED commercialization.

Unlike LCD technology that originated overseas, China has kept pace with the world in Mini/Micro-LED and has established a relatively complete industrial chain in it. Currently, the Mini LED is mainly used for LCD panel backlighting; It will be an inevitable trend for the direct LED display with Mini LED in large-screen in the future.

Regarding the Micro-LED technological progress choices, Chinese display manufacturers are facing challenges in mass transfer and full-color display. They are exploring and verifying multiple technical routes.

However, TFT-LCD technology will remain the mainstay for a long time in the future, because of its maturity and competitive prices. Multiple display technologies will coexist in the future; Micro-LED panels mass production will not be achieved in the short term.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Given the relatively low resolution of printing technology, QLED shall be difficult to reach a resolution greater than 300 PPI (pixels per inch) within a few years. Thus, QLED might not be applied for small-sized displays at present and its potential will be medium to large-sized displays.

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

Huang: Based on my understanding of Samsung, the leading Korean player in OLED market, we cannot say it had foresight in the very beginning. Samsung began to invest in AMOLED (active-matrix organic light-emitting diode, a major type of OLED used in the display industry) in about 2003, and did not realize mass production until 2007. Its OLED production reached profitability in 2010. Since then, Samsung gradually secured a market monopoly status.

So, originally, OLED was only one of Samsung"s several alternative technology pathways. But step by step, it achieved an advantageous status in the market and so tended to maintain it by expanding its production capacity.

Another reason is customers’ demands. Apple has refrained itself from using OLED for some years due to various reasons, including the patent disputes with Samsung. But after Apple began to use OLED for its iPhone X, it exerted a big influence in the whole industry. So now Samsung began to harvest its accumulated investments in the field and began to expand the capacity more.

Liao: South Korean manufacturers including Samsung and LG Electronics have controlled 90% of global supplies of medium and small-sized OLED panels. Since Apple began to buy OLED panels from Samsung for its cellphone products, there were no more enough panels shipping to China. Therefore, China"s current demands cannot be fully satisfied from the foreign companies. On the other hand, because China has a huge market for cellphones, it would be necessary to fulfill the demands through domestic efforts. That is why China must develop its OLED production capability.

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

Then it is the scale of human resources. One big factory will create several thousand jobs, and it will mobilize a whole production chain, involving thousands of workers. The requirement of supplying these engineers and skilled workers can be fulfilled in China.

The third advantage is the national supports. The government has input huge supports and manufacturers’ technological capacity is improving. I think Chinese manufacturers will have a great breakthrough in OLED.

Although we cannot say that our advantages triumph over ROK, where Samsung and LG have been dominating the field for many years, we have achieved many significant progresses in developing the material and parts of OLED. We also have high level of innovation in process technology and designs. We already have several major manufacturers, such as Visionox, BOE, EDO and Tianma, which have owned significant technological reserves.

Peng: As mentioned above, there are two ways to apply quantum dots for display, namely photoluminescence in backlightingFor QLED, the three stages of technological development [from science issue to engineering and finally to mass production] have been mingled together at the same time. If one wants to win the competition, it is necessary to invest on all three dimensions.

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

China is internationally leading in electroluminescence at present. In fact, it was the 2014 Nature publication by a group of scientists from Zhejiang University that proved QLED can reach the stringent requirements for display applications. However, who will become the final winner of the international competition on electroluminescence remains unclear. China"s investment in quantum-dot technology lags far behind US and ROK. Basically, the quantum-dot research has been centered in US for most of its history, and South Korean players have invested heavily along this direction as well.

For electroluminescence, it is very likely to co-exist with OLED for a long period of time. This is so because, in small screen, QLED’s resolution is limited by printing technology.

Peng: If electroluminescence can be successfully achieved with printing, it will be much cheaper, with only about 1/10th cost of OLED. Manufacturers like NajingTech and BOE in China have demonstrated printing displays with quantum dots. At present, QLED does not compete with OLED directly, given its market in small-sized screen. A while ago, Dr. Huang mentioned three stages of technological development, from science issue to engineering and finally to mass production. For QLED, the three stages have been mingled together at the same time. If one wants to win the competition, it is necessary to invest on all three dimensions.

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

It seems to be possible that the flexible display will eventually lead a killer advantage. I think QLED will also face similar situation. What is its real advantage if it is compared with OLED or LCD? For QLED, it seems to have been difficult to find the advantage in small screen. Dr. Peng has suggested its advantage lies in medium-sized screen, but what is its uniqueness?

Peng: The two types of key advantages of QLED are discussed above. One, QLED is based on solution-based printing technology, which is low cost and high yield. Two, quantum-dot emitters vender QLED with a large color gamut, high picture quality and superior device lifetime. Medium-sized screen is easiest for the coming QLED technologies but QLED for large screen is probably a reasonable extension afterwards.

Huang: But customers may not accept only better wider color range if they need to pay more money for this. I would suggest QLED consider the changes in color standards, such as the newly released BT2020 (defining high-definition 4 K TV), and new unique applications which cannot be satisfied by other technologies. The future of QLED seems also relying on the maturity of printing technology.

Peng: New standard (BT2020) certainly helps QLED, given BT2020 meaning a broad color gamut. Among the technologies discussed today, quantum-dot displays in either form are the only ones that can satisfy BT2020 without any optical compensation. In addition, studies found that the picture quality of display is highly associated with color gamut. It is correct that the maturity of printing technology plays an important role in the development of QLED. The current printing technology is ready for medium-sized screen and should be able to be extended to large-sized screen without much trouble.

Xu: For QLED to become a dominant technology, it is still difficult. In its development process, OLED precedes it and there are other rivaling technologies following. While we know owning the foundational patents and core technologies of QLED can make you a good position, holding core technologies alone cannot ensure you to become a mainstream technology. The government"s investment in such key technologies after all is small as compared with industry and cannot decide QLED to become mainstream technology.

Peng: Domestic industry sector has begun to invest in these future technologies. For example, NajingTech has invested about 400 million yuan ($65 million) in QLED, primarily in electroluminescence. There are some leading domestic players having invested into the field. Yes, this is far from enough. For example, there are few domestic companies investing R&D of printing technologies. Our printing equipment is primarily made by the US, European and Japan players. I think this is also a chance for China (to develop the printing technologies).

Liao: Due to their lack of kernel technologies, Chinese OLED panel manufacturers heavily rely on investments to improve their market competitiveness. But this may cause the overheated investment in the OLED industry. In recent years, China has already imported quite a few new OLED production lines with the total cost of about 450 billion yuan (US$71.5 billion).Lots of advantages of OLED over LCD were highlighted, such as high color gamut, high contrast and high response speed and so on …. It seems to be possible that the flexible display will eventually lead a killer advantage.

The short of talent human resources perhaps is another issue to influence the fast expansion of the industry domestically. For an example, BOE alone demands more than 1000 new engineers last year. However, the domestic universities certainly cannot fulfill this requirement for specially trained OLED working forces currently. A major problem is the training is not implemented in accordance with industry demands but surrounding academic papers.

Liao: However, Chinese researchers’ priority pursuit of papers is in disjunction from industry demand. Majority of people (at universities) who are working on organic optoelectronics are more interested in the fields of QLED, organic solar cells, perovskite solar cells and thin-film transistors because they are trendy fields and have more chances to publish research papers. On the other hand, many studies that are essential to solve industry"s problems, such as developing domestic versions of equipment, are not so essential for paper publication, so that faculty and students shed from them.

Zhao: Today there are really good observations, discussions and suggestions. The industry-academics-research collaboration is crucial to the future of China"s display technologies. We all should work hard on this.

Market research firm Sigmaintell said BOE Technology Group Co Ltd－a leading Chinese supplier of display products and solutions－became the world"s largest shipper of LCD TV panels for the first time in 2019.

The Beijing-based company shipped 53.3 million units of LCD panels in 2019, with production capacity increasing by more than 20 percent on a yearly basis.

The consultancy said the LCD TV panel production area of Chinese manufacturers will account for more than 50 percent of the global total this year, surpassing South Korean competitors who are accelerating the shutdown of large-sized LCD panel production capacity due to competition from Chinese manufacturers.

It estimated the production capacity of large-sized LCD panels will continue to increase in China over the next three years. In addition, global LCD TV panel shipments stood at 283 million pieces last year, a slight decrease of 0.2 percent year-on-year. Meanwhile, the shipment area was 160 million square meters, an increase of 6.3 percent year-on-year.

"Chinese companies have gained an upper hand in large-screen LCD displays. Samsung and LG"s decision to exit from the LCD sector means Chinese panel makers will take a dominant position in this field," said Li Dongsheng, founder and chairman of Chinese tech giant TCL Technology Group Corp.

Li said South Korean firms will focus on organic LED screens and quantum dot LED displays, while Chinese TV panel makers are catching up at a rapid pace.

Data consultancy Digitimes Research said it comes as little surprise that Samsung has opted to withdraw from the LCD panel sector as its LCD business was losing money in every quarter of 2019 due to challenges from Chinese competitors.

BOE said its Gen 10.5 TFTLCD production line achieved mass production in Hefei, Anhui province, in March 2018. The plant mainly produces high-definition LCD screens of 65 inches and above. With a total investment of 46 billion yuan ($6.5 billion), the company"s second Gen 10.5 TFT-LCD production line launched operations in Wuhan, Hubei province, in December.

The Gen 11 TFT-LCD and active-matrix OLED production line of Shenzhen China Star Optoelectronics Technology, a subsidiary of TCL, officially entered operations in November 2018, producing 43-inch, 65-inch and 75-inch LCD screens.

Bian said the OLED and QLED will be the next-generation flat-panel display technologies to be in the spotlight. LG Display is currently the world"s only supplier of large-screen OLED TV panels.

OLED is a relatively new technology and part of recent display innovation. It has a fast response rate, wide viewing angles, super high-contrast images and richer colors. It is much thinner and can be made flexible, compared with traditional LCD display panels.

Li Yaqin, general manager of Sigmaintell, said 65-inch TVs will become the mainstream in people"s living rooms in the future, but OLED TVs will not be able to immediately spur customer purchases at this time though the future trend is for higher-tech options.

Cluster and center console display research: how Chinese manufacturers scramble for Mini LED/Micro LE market. The surging demand for intelligent and connected vehicles, in-vehicle infotainment systems and navigation systems among others gives a big boost to the automotive display market.

New York, Jan. 24, 2022 (GLOBE NEWSWIRE) -- Reportlinker.com announces the release of the report "Global and China Automotive LCD Cluster and Center Console Industry Report, 2021" - https://www.reportlinker.com/p06219667/?utm_source=GNW

Automotive display is a key booster to the digital transformation of automotive cockpits. The better performance of on-board computers enables the central computing unit to support LCD cluster, high-resolution infotainment display, HUD, electronic rearview mirror and other display systems, and provides technical support for multi-display systems.

The installation of clusters shows that about 60% of new vehicles carry LCD clusters. In the first three quarters of 2021, 6.544 million LCD clusters were installed in passenger cars, a like-on-like spurt of 44.5%, of which 12.0-inch (incl.) to 13.0-inch (excl.) LCD clusters were most installed, up to 2.512 million units, up by 35.0%, and 10.0-inch (incl.) to 12.0-inch (excl.) LCD clusters grew at the fastest pace with the installations rocketing by 173.8% to 1.186 million units.

From center console displays, it can be seen that the installations of large-size ones have surged. In the first three quarters of 2021, 8.0-inch to 9.0-inch center console displays were most installed, up to 4.016 million units, up by 4.3% from the prior-year period, but with the proportion of the total center console display installations down 4.2 percentage points; the installations of 13.0-inch to 15.0-inch center console displays proliferated by 250.6%; that of 15.0-inch and above center console displays multiplied by 204.0%.

Cockpit electronics are heading in the direction of multi-display integration. Early in 2019, emerging carmakers have rolled out mass-produced models like LiXiang One and ENOVATE ME7 with 4 and even 5-screen displays. Traditional OEMs also step up efforts to deploy, having introduced multi-screen display products since 2020.

FAW Hongqi H9 unveiled in August 2020 bears dashboard, center console, and co-pilot seat entertainment displays, 2 rear row entertainment displays, and HUD. In addition, it also packs an electronic image acquisition and display system (i.e., streaming media rearview mirror) which consists of digital camera, image processing and high-definition digital display. The system uses the rear camera to project images onto the display, and displays them on the rearview mirror in digital format.

In the future, as standards and regulations are improved, more vehicle displays will be used. For example, in June 2021, Zhejiang Society of Automotive Engineers was approved for release of group standard, the Performance Requirements and Test Methods of Passenger Car Digital Perspective A-pillar System. Neta Auto under Hozon Auto introduced its “transparent A-pillar”-enabled mass-production models with OLED flexible screens as display interfaces. The issuance of this standard will accelerate the application of “transparent A-pillar”.

The soaring demand for vehicle displays give impetus to development of new vehicle display technologies. In current stage, a-Si TFT LCD still prevail in vehicle display market, but advanced display technologies such as LTPS TFT LCD, OLED, mini LED backlight and micro LED are making their way into the market.

The year of 2020 saw the start of production of automotive OLED. Due to high cost, OLED, often larger than 7.2 inches, is largely used in high-end models, with applications including cluster, center console and copilot seat entertainment displays. Suppliers are led by LGD, Samsung Display and BOE.

2021 Mercedes-Benz S-Class sedans differ greatly from the previous generations in application of displays, changing the original siamesed center console display into a large waterfall display, a 12.8-inch vertical waterfall OLED screen with resolution of 1888×1728. They also pack a glasses-free 3D full LCD dashboard, HUD and rear row entertainment display, which connect with each other.

Mercedes-Benz EQS rolled out overseas in September 2021 features an OLED flexible integrated touch screen that sweeps almost from A-pillar to A-pillar, and adopts innovative technologies like optically clear adhesives (OCA) and On-cell touch control.

2021 Cadillac Escalade is equipped with an OLED AR perspective curved display with three screens total – a 7.2-inch driver information display, a 14.2-inch digital dashboard, and a 16.9-inch infotainment screen. Wherein, the cluster option features a large speedometer displaying temperature and time at the left and dynamics at the right. In addition, the display is in night mode where infrared technology is used to observe farther than human eyes.

Mini LED is a necessary transition phase from fine pitch LED to Micro LED. At present, most vehicle display technology companies have deployed Mini LED and Micro LED, and ever more vehicle projects use mini LED backlight technology. One example is Cadillac Lyriq EV in which GM plans to use a 33-inch mini LED backlit display in 2022.

In November 2021, Mecha Dragon, the first model of SL, a high-end brand of Great Wall Motor made a debut at Auto Guangzhou. The Mini-LED external display technology at the rear of this model enables display of user-defined content, the first attempt to apply Mini-LED in cars.

Automotive displays head in the direction of large size and multi-screen integration, and the surging demand creates huge room to grow. Various suppliers are therefore trying hard to deploy innovative technologies such as Mini LED and Micro LED.

Tianma Microelectronics works to deploy Mini LED and Micro LED technologies. Following the on-site exhibition of its self-developed LTPS AM Mini LED HDR display at annual meeting of Society for Information Display (SID) early in 2019, the company showcased its Micro LED technologies online at SID 2021, including 5.04" Splitting ultra-narrow bezel Micro LED, the world’s first 7.56" transparent Micro LED, and innovative technology applications combined with electronic paper.

Moreover, its self-developed Hybrid TFT Display (HTD) technology is in the phase of verification for mass production. The company has deployed HTD on its flexible AMOLED production lines, and will achieve mass production based on the advanced drive and backplane technologies with lower power consumption.

HGC Lighting Solutions: the new-generation white light Mini LED vehicle backlight display module features automotive-grade reliability, ultra-thin display body, multi-zone dynamic control, and million-level ultra-high contrast.

This white light Mini LED display module uses automotive chip and self-developed superior ACSP chip-scale packaging technology. By removing the cost of QD and DBEF and upgrading the production process, it not only delivers automotive-grade reliability but cuts 15-25% production cost. The company have spawned and delivered white light Mini LED vehicle display series products and partnered with several well-known automakers.

China automotive display market (installation of LCD/HUD/center console/rear seat entertainment displays, display technologies of major suppliers, vehicle display installation schemes of major OEMs, etc.);

KLA is proud to be part of the most significant technological breakthroughs that help create the devices and ideas that transform our current life and shape our future. One of the latest emerging trends is a renewed focus on microLED technology.

As the name suggests, a microLED, or µLED, is a light-emitting diode (LED) – roughly 100 times smaller than conventional LEDs. MicroLEDs can be arranged into arrays to make high-resolution displays for applications ranging from smartwatches to very large displays – unlike conventional LEDs, which are suitable only for very large displays like billboards or stadium screens.

MicroLED technology was invented in 2000. However, it wasn"t until 2012 that a major consumer electronics company demonstrated a 55-inch, high-definition microLED TV. Other companies followed with their own demonstrations in 2018 and 2019 at retail prices of $80,000 for 89-inch models, making the technology out of reach for most consumers. Although microLED can potentially offer significant advantages over LCD or organic light-emitting diode (OLED) screens, technology issues and production costs have prevented widespread commercialization.

KLA – which has supported the global display industry for more than 40 years – has during the past decade been helping leaders in microLED technologies to overcome many of the obstacles to mass production and reduced costs.

"Our proven process and process control products are designed to meet the unique and demanding challenges of the complex microLED production flow to help accelerate wide market adoption," said Chet Lenox, KLA fellow, industry and customer collaboration.

While more products, based on slightly larger "miniLEDs" (typically ~50µm-300µm square), have been brought to market successfully in recent years as a way to improve on traditional LED backlighting for LCD displays, screen manufacturers and their supply chain are still committed to developing the more advanced microLED technology. In addition to the key goal of reducing product cost for consumers, companies are investing heavily in microLEDs for use in small products like watches and augmented reality (AR) headsets because they deliver better energy efficiency, consistent pixel quality and other key benefits as shown in the graphics below.

The potential market is huge. Shipping for microLED displays is expected to total 5 million and generate $7 billion in revenue by 2025, rising to more than 11 million units shipped in 2027, according to global technology research firm Omdia.

A key factor behind the industry"s focus on microLEDs is that LCD and OLED displays are produced on large substrates, where all layers are deposited one after the other. The larger the substrate, the more efficient the process – but large single displays can be difficult to handle and ship. MicroLEDs displays, however, can be produced using seamless tiling of small modules into larger displays.

The schematic cross-section of a typical microLED display (below) shows the simpler and thinner structure of a microLED compared to a thin film transistor liquid crystal display (TFT LCD) or OLED display, with the red/green/blue LED chips and a single electrode encased between the substrate and glass cover. The precise arrangement of the red, green and blue sub-pixels will vary among models and may even be stacked on top of each other.

MicroLEDs offer viewing performance equivalent to or, for some criteria such as brightness and refresh rate, better than OLED and LCD technologies. They also offer a longer life than OLED, thinner packaging and generally better energy efficiencies.

*Mass transferring millions of micro-sized red, green and blue microLEDs in the desired arrangement and precise locations (Solutions to avoid this might include the use of white or blue microLEDs with color conversion, growing uLEDs directly on silicon backplanes or using wafer-bonding of epi layers on the backplane.)

Each of the above would seem to add cost and make LCDs and OLEDs more economical. However, KLA"s metrology, inspection, wafer processing and repair solutions are critical to helping microLED manufacturers address these challenges, optimize yields, reduce the need for built-in redundancy and reduce expenditures to help microLED displays become a viable alternative to the established technologies.

KLA"s comprehensive portfolio of solutions for microLED manufacturing provides a pathway to yield improvement throughout the entire process – from epitaxy wafer to final display. KLA"s proven process and process control products are designed to meet the unique and demanding challenges of complex microLED production.

LCD manufacturers are mainly located in China, Taiwan, Korea, Japan. Almost all the lcd or TFT manufacturers have built or moved their lcd plants to China on the past decades. Top TFT lcd and oled display manufactuers including BOE, COST, Tianma, IVO from China mainland, and Innolux, AUO from Tianwan, but they have established factories in China mainland as well, and other small-middium sizes lcd manufacturers in China.

China flat display revenue has reached to Sixty billion US Dollars from 2020. there are 35 tft lcd lines (higher than 6 generation lines) in China,China is the best place for seeking the lcd manufacturers.

The first half of 2021, BOE revenue has been reached to twenty billion US dollars, increased more than 90% than thesame time of 2020, the main revenue is from TFT LCD, AMoled. BOE flexible amoled screens" output have been reach to 25KK pcs at the first half of 2021.the new display group Micro LED revenue has been increased to 0.25% of the total revenue as well.

Established in 1993 BOE Technology Group Co. Ltd. is the top1 tft lcd manufacturers in China, headquarter in Beijing, China, BOE has 4 lines of G6 AMOLED production lines that can make flexible OLED, BOE is the authorized screen supplier of Apple, Huawei, Xiaomi, etc,the first G10.5 TFT line is made in BOE.BOE main products is in large sizes of tft lcd panel,the maximum lcd sizes what BOE made is up to 110 inch tft panel, 8k resolution. BOE is the bigger supplier for flexible AM OLED in China.

As the market forecast of 2022, iPhone OLED purchasing quantity would reach 223 million pcs, more 40 million than 2021, the main suppliers of iPhone OLED screen are from Samsung display (61%), LG display (25%), BOE (14%). Samsung also plan to purchase 3.5 million pcs AMOLED screen from BOE for their Galaxy"s screen in 2022.

Technology Co., Ltd), established in 2009. CSOT is the company from TCL, CSOT has eight tft LCD panel plants, four tft lcd modules plants in Shenzhen, Wuhan, Huizhou, Suzhou, Guangzhou and in India. CSOTproviding panels and modules for TV and mobile

three decades.Tianma is the leader of small to medium size displays in technologyin China. Tianma have the tft panel factories in Shenzhen, Shanhai, Chendu, Xiamen city, Tianma"s Shenzhen factory could make the monochrome lcd panel and LCD module, TFT LCD module, TFT touch screen module. Tianma is top 1 manufactures in Automotive display screen and LTPS TFT panel.

Tianma and BOE are the top grade lcd manufacturers in China, because they are big lcd manufacturers, their minimum order quantity would be reached 30k pcs MOQ for small sizes lcd panel. price is also top grade, it might be more expensive 50%~80% than the market price.

Panda electronics is established in 1936, located in Nanjing, Jiangshu, China. Panda has a G6 and G8.6 TFT panel lines (bought from Sharp). The TFT panel technologies are mainly from Sharp, but its technology is not compliance to the other tft panels from other tft manufactures, it lead to the capacity efficiency is lower than other tft panel manufacturers. the latest news in 2022, Panda might be bougt to BOE in this year.

Established in 2005, IVO is located in Kunsan,Jiangshu province, China, IVO have more than 3000 employee, 400 R&D employee, IVO have a G-5 tft panel production line, IVO products are including tft panel for notebook, automotive display, smart phone screen. 60% of IVO tft panel is for notebook application (TOP 6 in the worldwide), 23% for smart phone, 11% for automotive.

Besides the lcd manufacturers from China mainland,inGreater China region,there are other lcd manufacturers in Taiwan,even they started from Taiwan, they all have built the lcd plants in China mainland as well,let"s see the lcd manufacturers in Taiwan:

Innolux"s 14 plants in Taiwan possess a complete range of 3.5G, 4G, 4.5G, 5G, 6G, 7.5G, and 8.5G-8.6G production line in Taiwan and China mainland, offering a full range of large/medium/small LCD panels and touch-control screens.including 4K2K ultra-high resolution, 3D naked eye, IGZO, LTPS, AMOLED, OLED, and touch-control solutions,full range of TFT LCD panel modules and touch panels, including TV panels, desktop monitors, notebook computer panels, small and medium-sized panels, and medical and automotive panels.

AUO is the tft lcd panel manufacturers in Taiwan,AUO has the lcd factories in Tianma and China mainland,AUOOffer the full range of display products with industry-leading display technology,such as 8K4K resolution TFT lcd panel, wide color gamut, high dynamic range, mini LED backlight, ultra high refresh rate, ultra high brightness and low power consumption. AUO is also actively developing curved, super slim, bezel-less, extreme narrow bezel and free-form technologies that boast aesthetic beauty in terms of design.Micro LED, flexible and foldable AMOLED, and fingerprint sensing technologies were also developed for people to enjoy a new smart living experience.

Hannstar was found in 1998 in Taiwan, Hannstar display hasG5.3 TFT-LCD factory in Tainan and the Nanjing LCM/Touch factories, providing various products and focus on the vertical integration of industrial resources, creating new products for future applications and business models.

driver, backlight etc ,then make it to tft lcd module. so its price is also more expensive than many other lcd module manufacturers in China mainland.

Maclight is a China based display company, located in Shenzhen, China. ISO9001 certified, as a company that more than 10 years working experiences in display, Maclight has the good relationship with top tft panel manufacturers, it guarantee that we could provide a long term stable supply in our products, we commit our products with reliable quality and competitive prices.

Maclight products included monochrome lcd, TFT lcd module and OLED display, touch screen module, Maclight is special in custom lcd display, Sunlight readable tft lcd module, tft lcd with capacitive touch screen. Maclight is the leader of round lcd display. Maclight is also the long term supplier for many lcd companies in USA and Europe.

If you want tobuy lcd moduleorbuy tft screenfrom China with good quality and competitive price, Maclight would be a best choice for your glowing business.

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To evaluate the performance of display devices, several metrics are commonly used, such as response time, CR, color gamut, panel flexibility, viewing angle, resolution density, peak brightness, lifetime, among others. Here we compare LCD and OLED devices based on these metrics one by one.

where Tf is the frame time (e.g., Tf=16.67 ms for 60 fps). Using this equation, we can easily obtain an MPRT as long as the LC response time and TFT frame rate are known. The results are plotted in Figure 5.

From Figure 5, we can gain several important physical insights: (1) Increasing the frame rate is a simple approach to suppress image motion blur, but its improvement gradually saturates. For example, if the LC response time is 10 ms, then increasing the frame rate from 30 to 60 fps would significantly reduce the MPRT. However, as the TFT frame rate continues to increase to 120 and 240 fps, then the improvement gradually saturates. (2) At a given frame rate, say 120 fps, as the LC response time decreases, the MPRT decreases almost linearly and then saturates. This means that the MPRT is mainly determined by the TFT frame rate once the LC response time is fast enough, i.e., τ≪Tf. Under such conditions, Equation (1) is reduced to MPRT≈0.8Tf. (3) When the LC response is <2 ms, its MPRT is comparable to that of an OLED at the same frame rate, e.g., 120 fps. Here we assume the OLED’s response time is 0.

The last finding is somehow counter to the intuition that a LCD should have a more severe motion picture image blur, as its response time is approximately 1000 × slower than that of an OLED (ms vs. μs). To validate this prediction, Chen et al.

If we want to further suppress image blur to an unnoticeable level (MPRT<2 ms), decreasing the duty ratio (for LCDs, this is the on-time ratio of the backlight, called scanning backlight or blinking backlight) is mostly adopted

High CR is a critical requirement for achieving supreme image quality. OLEDs are emissive, so, in theory, their CR could approach infinity to one. However, this is true only under dark ambient conditions. In most cases, ambient light is inevitable. Therefore, for practical applications, a more meaningful parameter, called the ACR, should be considered

To investigate the ACR, we have to clarify the reflectance first. A large TV is often operated by remote control, so touchscreen functionality is not required. As a result, an anti-reflection coating is commonly adopted. Let us assume that the reflectance is 1.2% for both LCD and OLED TVs. For the peak brightness and CR, different TV makers have their own specifications. Here, without losing generality, let us use the following brands as examples for comparison: LCD peak brightness=1200 nits, LCD CR=5000:1 (Sony 75″ X940E LCD TV); OLED peak brightness=600 nits, and OLED CR=infinity (Sony 77″ A1E OLED TV). The obtained ACR for both LCD and OLED TVs is plotted in Figure 7a. As expected, OLEDs have a much higher ACR in the low illuminance region (dark room) but drop sharply as ambient light gets brighter. At 63 lux, OLEDs have the same ACR as LCDs. Beyond 63 lux, LCDs take over. In many countries, 60 lux is the typical lighting condition in a family living room. This implies that LCDs have a higher ACR when the ambient light is brighter than 60 lux, such as in office lighting (320–500 lux) and a living room with the window shades or curtain open. Please note that, in our simulation, we used the real peak brightness of LCDs (1200 nits) and OLEDs (600 nits). In most cases, the displayed contents could vary from black to white. If we consider a typical 50% average picture level (i.e., 600 nits for LCDs vs. 300 nits for OLEDs), then the crossover point drops to 31 lux (not shown here), and LCDs are even more favorable. This is because the on-state brightness plays an important role to the ACR, as Equation (2) shows.

Calculated ACR as a function of different ambient light conditions for LCD and OLED TVs. Here we assume that the LCD peak brightness is 1200 nits and OLED peak brightness is 600 nits, with a surface reflectance of 1.2% for both the LCD and OLED. (a) LCD CR: 5000:1, OLED CR: infinity; (b) LCD CR: 20 000:1, OLED CR: infinity.

Recently, an LCD panel with an in-cell polarizer was proposed to decouple the depolarization effect of the LC layer and color filtersFigure 7b. Now, the crossover point takes place at 16 lux, which continues to favor LCDs.

For mobile displays, such as smartphones, touch functionality is required. Thus the outer surface is often subject to fingerprints, grease and other contaminants. Therefore, only a simple grade AR coating is used, and the total surface reflectance amounts to ~4.4%. Let us use the FFS LCD as an example for comparison with an OLED. The following parameters are used in our simulations: the LCD peak brightness is 600 nits and CR is 2000:1, while the OLED peak brightness is 500 nits and CR is infinity. Figure 8a depicts the calculated results, where the intersection occurs at 107 lux, which corresponds to a very dark overcast day. If the newly proposed structure with an in-cell polarizer is used, the FFS LCD could attain a 3000:1 CRFigure 8b), corresponding to an office building hallway or restroom lighting. For reference, a typical office light is in the range of 320–500 luxFigure 8 depicts, OLEDs have a superior ACR under dark ambient conditions, but this advantage gradually diminishes as the ambient light increases. This was indeed experimentally confirmed by LG Display

Calculated ACR as a function of different ambient light conditions for LCD and OLED smartphones. Reflectance is assumed to be 4.4% for both LCD and OLED. (a) LCD CR: 2000:1, OLED CR: infinity; (b) LCD CR: 3000:1, OLED CR: infinity. (LCD peak brightness: 600 nits; OLED peak brightness: 500 nits).

For conventional LCDs employing a WLED backlight, the yellow spectrum generated by YAG (yttrium aluminum garnet) phosphor is too broad to become highly saturated RGB primary colors, as shown in Figure 9aTable 2. The first choice is the RG-phosphor-converted WLEDFigure 9b, the red and green emission spectra are well separated; still, the green spectrum (generated by β-sialon:Eu2+ phosphor) is fairly broad and red spectrum (generated by K2SiF6:Mn4+ (potassium silicofluoride, KSF) phosphor) is not deep enough, leading to 70%–80% Rec. 2020, depending on the color filters used.

Transmission spectra of color filters and emission spectra of (a) YAG WLED, (b) KSF WLED, (c) QDEF and (d) Vivid Color LED. KSF, potassium silicofluoride; QDEF, quantum dot enhancement film; WLED, white light-emitting diode; YAG, yttrium aluminum garnet.

Recently, a new LED technology, called the Vivid Color LED, was demonstratedFigure 9d), which leads to an unprecedented color gamut (~98% Rec. 2020) together with specially designed color filters. Such a color gamut is comparable to that of laser-lit displays but without laser speckles. Moreover, the Vivid Color LED is heavy-metal free and shows good thermal stability. If the efficiency and cost can be further improved, it would be a perfect candidate for an LCD backlight.

A color filter array is another effective approach to enhance the color gamut of an OLED. For example, in 2017, AUO demonstrated a 5-inch top-emission OLED panel with 95% Rec. 2020. In this design, so-called symmetric panel stacking with a color filter is employed to generate purer RGB primary colors

As mentioned earlier, TFT LCDs are a fairly mature technology. They can be operated for >10 years without noticeable performance degradation. However, OLEDs are more sensitive to moisture and oxygen than LCDs. Thus their lifetime, especially for blue OLEDs, is still an issue. For mobile displays, this is not a critical issue because the expected usage of a smartphone is approximately 2–3 years. However, for large TVs, a lifetime of >30 000 h (>10 years) has become the normal expectation for consumers.

Here we focus on two types of lifetime: storage and operational. To enable a 10-year storage lifetime, according to the analysis−6 g (m2-day)−1 and 1 × 10−5 cm3 (m2-day)−1, respectively. To achieve these values, organic and/or inorganic thin films have been developed to effectively protect the OLED and lengthen its storage lifetime. Meanwhile, it is compatible to flexible substrates and favors a thinner display profile

The next type of lifetime is operational lifetime. Owing to material degradation, OLED luminance will decrease and voltage will increase after long-term drivingT50) can be as long as >80 000 h with a 1000 cd m−2 luminanceT50, half lifetime) with an initial luminance of 1000 nits. However, this is still ~20 × shorter than that of red and green phosphorescent OLEDs

To further enhance the lifetime of the blue OLED, the NTU group has developed new ETL and TTF-EML materials together with an optimized layer structure and double EML structureFigure 10a shows the luminance decay curves of such a blue OLED under different initial luminance values (5000, 10 000, and 15 000 nits). From Figure 10b, the estimated T50 at 1000 nits of this blue OLED is ~56 000 h (~6–7 years)

Power consumption is equally important as other metrics. For LCDs, power consumption consists of two parts: the backlight and driving electronics. The ratio between these two depends on the display size and resolution density. For a 55″ 4K LCD TV, the backlight occupies approximately 90% of the total power consumption. To make full use of the backlight, a dual brightness enhancement film is commonly embedded to recycle mismatched polarized light

The power efficiency of an OLED is generally limited by the extraction efficiency (ηext~20%). To improve the power