According to reports from Electronic Enthusiasts Network (by Wu Zipeng), in the digital age, as the information display carrier and human-computer interaction window, displays can be said to be ubiquitous, including smart homes, intelligent cockpits, smart healthcare, and social media, all relying on screens as carriers of information display. Currently, innovative display technologies are emerging continuously, with screens becoming lighter and thinner, while flexible display technology has made significant progress.
In fact, displays have a development history of over a hundred years today, during which they have undergone many generations of different mainstream display technologies, gradually forming the diversified and prosperous situation of today’s displays.
CRT (Cathode Ray Tube) is the first generation of mainstream display technology, invented by Braun in 1897 and later introduced into the display industry, becoming the most mainstream display technology of the 20th century. CRT monitors mainly consist of three main components: the electron gun, the phosphorescent screen, and the glass shell. More specifically, CRT monitors include screen glass, phosphor, aluminum film, inner graphite layer, outer graphite layer, deflection coils, first/second/third/fourth anodes, cathode, control grid, filament, and high-voltage nozzle.
The imaging principle of CRT is that when the filament heats up, the cathode emits an electron beam, and the electron beam changes according to the image information of the grid and cathode. The electron beam is then accelerated by the anode and adjusted by the deflection coils, finally hitting the phosphorescent screen at high speed, forming different gray levels on the screen to complete the image display.
In 1907, Russian scientist Boris Rosing first displayed geometric figures on the screen using CRT technology, although this was not the first display in history. The first display was born in 1922; then in 1925, Baird invented the first television; in 1936, the 11th Berlin Olympics realized live television broadcasting for the first time, accelerating the popularity of CRT televisions.
In the Chinese market, the first CRT television was born in 1958, a black-and-white television, which later received many colloquial names from the Chinese people, including “back head” and “big butt.” In 1970, China produced its first color CRT television, which generated color visual effects through the combination of red (R), green (G), and blue (B) primary colors, with the electron beam gun equipped with three cathodes, each bombarding different phosphors to complete the display.
The 1980s and 1990s were the stage of large-scale popularity of CRT televisions in the country; however, due to the bulky form of this display technology, it ultimately lost to LCD display technology.
In fact, LCD was born in 1964 and became a liquid crystal display in 1968. However, in the early stages of technological development, due to the more mature CRT technology, LCD could not compete with CRT in response time, color reproduction, resolution, etc., and could only be used for simple digital displays like electronic calculators and watches. Between 1968 and 1971, dynamic scattering technology was mainly used to produce liquid crystal displays, also known as DS-LCD, but this method easily damaged the liquid crystal, so it did not last long.
From 1971 to 1990, the industry successively developed TN-LCD (Twisted Nematic LCD) and STN-LCD (Super Twisted Nematic LCD). By the STN-LCD stage, the performance of liquid crystal displays had significantly improved, leading CRT display technology in terms of resolution, viewing angles, and contrast.
In 1988, TFT-LCD (Thin Film Transistor LCD) was born, with Japanese manufacturers leading significantly in this area. TFT-LCD drastically reduced the production cost of liquid crystal displays, ultimately surpassing CRT’s market share. TFT-LCD later evolved into IPS, also known as “Super TFT,” a type of in-plane switching screen technology. IPS has since branched into several subcategories, including IPS, S-IPS, AS-IPS, and IPS-PRO.
From the perspective of panel types, while TN-LCD and IPS were developing, the industry chain led by Sharp also invented VA liquid crystal panels, which are actually a variant of TFT-LCD. Like TN-LCD, VA liquid crystal is also a soft screen used for making curved screens. IPS is a hard screen but has excellent all-angle characteristics, dynamic clarity, and color reproduction.
To date, TN-LCD, IPS, and VA have their own main battlefields. Among them, TN-LCD has become mainstream in the gaming monitor market due to its low manufacturing cost and fast response speed; IPS, with its vivid colors and natural saturation, can also display dynamic high-definition images without ghosting or trailing, mainly used for professional monitors aimed at photography, design, video editing, and other scenarios; VA liquid crystal, with its high tolerance and contrast, purer black and white, and flexible characteristics, is mainly used for high-end televisions and most curved screens on the market.
The Short-lived Plasma Technology
While LCD dominates the global display market, it also faces competition from the original ruler CRT and concurrent plasma technology.
Plasma display technology was born in 1927 and was officially applied to displays in 1964. Although plasma technology originated in the United States, its real development occurred in Japan. American companies hoped to use plasma technology for displays and computer screens, but the results were not ideal. In 1994, Panasonic began to jointly develop color plasma technology with Plasmaco, which was acquired by Panasonic in 1996. In the 1990s, the main researchers of plasma technology were Panasonic and Fujitsu, followed by Philips, Pioneer, Samsung, LG, and Changhong joining in.
Statistics from 2006 showed that at that time, the shipment volume of LCD and plasma televisions worldwide was comparable. Subsequently, plasma technology began to fall into disputes over technological factions, and its market performance was gradually suppressed by LCD, leading to Panasonic’s announcement to cease production of plasma panels by the end of 2013.
The Future Mainstream OLED
The birth of OLED was an accidental discovery. In 1979, Dr. Dong Qingyun, who worked at Kodak, accidentally discovered that organic batteries emitted light when he forgot to bring something and returned to the lab, thus starting the research on OLED. The world’s first commercial OLED came from Kodak, released in 1987. Upon release, OLED exhibited characteristics of being thinner, blacker, and faster in response.
Before 2005, the technological development of OLED was dominated by Kodak, Pioneer, and UDC. During this period, the industry discovered the flexible characteristics of OLED and successively realized its commercial use in devices such as cars, cameras, and displays. Meanwhile, Kodak teamed up with Sanyo in 1998 to achieve full-color OLED.
In 2005, Samsung invested $850 million to build AMOLED production lines, marking the entry of OLED into the maturity phase, with Samsung becoming one of the main suppliers of OLED.
OLED has two technical routes: one is PMOLED, and the other is AMOLED. PMOLED has a relatively simple process and straightforward structure but cannot be made into large sizes and lacks color display richness, so it was once used for the outer screen of mobile phones; AMOLED has a complex structure and higher costs but offers richer colors and can be made in various sizes, making it the mainstream in the industry today.
In the smartphone market, Siemens was the first to commercialize AMOLED, but it was Samsung that truly made it a standard for high-end devices. From the first generation of the Galaxy S series, Samsung deeply bound high-end flagships with AMOLED, and every generation of Samsung’s flagship phones has led the industry by at least one generation. In 2017, Apple used AMOLED for the first time in the iPhone X.
In the television market, Sony launched an OLED TV in 2007, but the market response was mediocre. Subsequently, LG entered the OLED TV market in 2013, making OLED TVs the mainstream of high-end televisions. Currently, LG and Sony are the main OLED TV brands, with LG almost monopolizing global OLED TV panel supply, allocating 82% of production capacity to LG and Sony, while the remaining share is divided among brands like Hisense, Skyworth, and Xiaomi.
Full of Imagination: Micro LED
Micro LED refers to the miniaturization and matrix technology of LED. The technology history of LED can be traced back to 1907, but red LED commercialization began in 1962. However, for more than thirty years afterward, the industry had not conquered blue LED technology until Japanese scientist Shuji Nakamura developed blue LED using a GaN substrate in 1994, which allowed the development of full-color LEDs and laid the technical foundation for white LEDs.
Traditional LEDs mainly have two application directions: one is as a backlight source, widely used in mobile phones, digital cameras, televisions, displays, etc.; the other is direct display, mainly used for commercial splicing large screens.
From LED to Micro LED, there is an intermediate step, which is Mini LED, a new display technology that is currently the focus of major manufacturers. However, some analysts believe that Mini LED is a transitional product. Mini LED and Micro LED differ in chip size, with Mini LED chip sizes ranging from 50-200μm and Micro LED being less than 100μm; there are significant differences in chip preparation, as Mini LED still requires sapphire substrates, whereas Micro LED does not.
From a direct display perspective, Mini LED is indeed a transitional product from LED to Micro LED. During this process, the industry will successively validate technologies such as mass transfer and advanced LED packaging to prepare for the commercial use of Micro LED. However, currently, Mini LED backlight is shining brightly, as Mini LED is unique in this area since Micro LED will not be used for backlighting. Therefore, it can be said that Mini LED backlight is a major trend for the future development of traditional LCDs, continuing to extend the technological lifespan of LCDs.
Returning to Micro LED. Since the Japanese Satoshi Takano team released a set of Micro LED arrays in 2001, this technology has developed for over twenty years. However, due to the transition from traditional sapphire substrates to silicon substrates and the challenges of mass transfer technology, Micro LED is still far from large-scale commercial use. Nevertheless, the potential of Micro LED cannot be ignored; through the thin-film, miniaturization, and arraying of LEDs, Micro LED inherits the high efficiency, high brightness, high reliability, and fast response time of inorganic LEDs, and it brings significant improvements in display resolution, coupled with advantages such as energy efficiency, simple structure, small size, and thinness, the industry will continue to invest in Micro LED.
It is expected that in 2024, Micro LED will welcome its commercial year, with the first products being portable devices such as watches and VR, as well as high-end televisions.
As a window for human-computer interaction, displays will continue to update related technologies under the promotion of digitization and intelligence, with new display technologies constantly emerging. Today, LCD, with its mature industrial chain advantages, combined with the support of Mini LED backlighting, will still occupy the mainstream of the display market for a long time. However, the transition to OLED is inevitable. In addition to the continuous update of display technologies, supporting technologies such as video interfaces for displays are also developing rapidly. These technologies combined not only bring people a better visual experience but also make life increasingly rich in technological sense.
Disclaimer: This article is originally from Electronic Enthusiasts. Please indicate the source above when reprinting. If you need to join the group for communication, please add WeChat elecfans999, for submission and interview requests, please send an email to [email protected].
More Hot Articles to Read
-
Mercedes-Benz plans to cancel “oil-to-electric”; will the EQ brand soon become history, and is all-in pure electricity the right path?
-
Manufacturing inventory begins to ease; the last darkness before market recovery.
-
AITO Wenjie, Tesla slashes prices! Will 2023 new energy vehicles usher in a new round of elimination?
-
Cancel physical buttons, switch to Type-C; all the latest news on Apple’s iPhone 15 is here.
-
Electronic rearview mirrors officially approved; vehicle-mounted cameras and displays welcome new growth points!
