The Mini LED direct display television is still in the conceptual stage and cannot replace the LCD and LED displays on the market in the short term, with at least five years to go before mass production.
On July 22, 2020, Mini LED products were exhibited at the Display Technology and Application Innovation Exhibition. Image/Visual China
By | Caijing Reporter Fang Shuo
Editor | Yu Le
On December 11, TCL Technology (000100.SZ) announced that it would acquire 100% equity of Maojia International held by TCL Industries (Hong Kong) in cash, with a transaction price of 2.8 billion yuan.The main purpose of this acquisition is to shorten the development cycle of new technologies and products such as Mini LED.
The mainstream products in the panel industry are currently LED and LCD, but companies are still exploring new technological directions. Once, OLED was considered a key future path, but before OLED could gain traction, Mini LED has arrived.
Compared with the traditional LCD and LED displays that are most common on the market, Mini LED displays have a larger number and density of chips behind them, providing more vivid picture quality and the ability to present more detailed displays. This type of screen is mainly used in products such as television displays, laptop monitors, and gaming monitors.
Since 2019, leading companies in the panel industry such as TCL, Sony, and BOE (000725.SZ) have launched Mini LED products, including television displays, computer displays, and automotive displays. TCL’s 75-inch Xingyao screen and Xiaomi’s 82-inch Supreme Commemorative Edition TV are both Mini LED backlit displays.Previously, there were rumors in the industry chain that Samsung and Apple would launch new Mini LED products in 2021. As of the time of publication, neither Samsung nor Apple has responded to Caijing’s reporter’s verification.
As leading consumer electronics manufacturers, Apple, Samsung, and TCL have a strong guiding role. Once the news of these three companies entering the Mini LED market emerged, it quickly drove the upgrading and development of the industry chain.
Upstream chip manufacturers in the industry chain, San’an Optoelectronics (600703.SH) and Jufei Optoelectronics (300303.SZ), have announced the start of mass production of Mini LED chips.TCL’s panel company Huaxing Optoelectronics is focusing its research and production of Mini LED on gaming screens, automotive screens, and television screens. BOE is also actively laying out Mini LED as a key project for the company.
However, several industry insiders told Caijing that although the development potential of Mini LED is enormous, it is still only in the conceptual stage, and there is a long way to go before mass production.
The Entry of Mini LED
The current mainstream television displays are LCD and LED displays. LCD (Liquid Crystal Display) screens do not emit light on their own; they require a backlight to display images. LED (Light Emitting Diode) displays are similar to LCD displays, with the only difference being the form of the backlight. The backlight for LCD displays is provided by lamp tubes, while LED displays use LEDs, or light-emitting diodes, as the backlight source.
Mini LED refers to mini light-emitting diodes. Compared to ordinary LED displays, Mini LED displays have a higher pixel density per unit area and a smaller light source size, allowing for greater brightness and controllable color gamut. For a 50-inch display, an ordinary LED might require about 60 chips, while Mini LED requires thousands.
The application direction of Mini LED is divided into two types: backlight and direct display. Backlight screens are essentially still LED backlight sources, just with smaller chip sizes and more chips; direct display screens eliminate the backlight panel, which means the screen can be thinner, has faster response times, and is less prone to burn-in. These products mainly occupy the ultra-high-end display market and commercial market. Although the quantity is small, the prices are high, thus the market scale remains considerable.
According to information provided by Huaxing Optoelectronics, the first Mini LED backlit screen television launched by TCL can achieve a resolution of 8K (7680×4320). The current mainstream television displays are still primarily 4K and 1080P. In terms of contrast, traditional LCDs have a contrast ratio of about 1000 to 1, while TCL Huaxing’s Mini LED has a contrast ratio of up to 1 million to 1, providing richer detail representation.
A relevant person from TCL Huaxing Optoelectronics told Caijing that they are optimistic about Mini LED mainly because it has the potential to iterate on existing display technologies. There is a basic rule in the iterative development of display technology: image quality (resolution, color, response speed, contrast, etc.) and form (thinness, flexibility, etc.) determine the feasibility of technological replacement, while cost determines the penetration rate of technological replacement.
Mini LED has technological advantages, but from a cost perspective, it cannot replace the current mainstream panels in the short term.
The number of chips directly correlates with cost. Chen, the R&D and production manager at Huahao Weiye Optoelectronics, stated: “For the same size screen, the cost of Mini LED can differ by dozens of times from that of a regular LCD screen. As it stands, LCD does not have any defects. If Mini LED’s costs do not come down, LCD will not be replaced by Mini LED.”
Aside from mainstream television displays, the entry of Mini LED displays has limited impact on OLED displays.
OLED stands for organic light-emitting diode. When current passes through, these organic materials emit light on their own, essentially functioning as a panel that emits light. According to research reports from Qianzhan Economics, OLED panels have characteristics such as wide viewing angles, lightweight, and flexible folding capabilities, making them highly competitive in the wearable devices sector. Compared to traditional LCD displays, OLEDs are thinner, brighter, and more flexible. Many smartphones and wearable devices on the market use OLEDs.
Research reports from Dongguan Securities indicate that under current technology, the main advantages of OLED lie in flexibility and folding. In the future, as 5G, the Internet of Things, and wearable devices become more integrated into consumers’ lives, the application scenarios for OLED will become more diverse, while the main application of Mini LED displays remains in display screens.
A staff member from Huaxing Optoelectronics also told Caijing that in the future, Mini LED and OLED will coexist, being applied in different fields or terminals.
A technician from BOE told Caijing: “Mini LED is an upgraded product based on traditional panels, more stable and with smaller steps. OLED is a completely new direction and should not be replaced.”
OLED has distinct advantages in small-size display panels, but in large-size screens, Mini LED has more advantages than OLED. Due to its technical limitations, OLED has a low yield rate, and the cost of using it for large-size displays is extremely high. A 100-inch OLED screen can only have 3 defective pixels, but the probability of defects is highly unpredictable. Chen stated, “If Mini LED can be commercialized and its costs come down, it is very likely to replace OLED screens larger than 100 inches.”
Domestic Manufacturers Are Still Observing
Although major panel manufacturers are laying out Mini LED, whether for backlight or direct display screens, there is still a long way to go before large-scale commercialization.
Chen stated to Caijing, “In terms of Mini backlight screens, there is no demand from the terminal. It is driven by the upstream industry chain. The overall capacity of domestic LED is in excess, and new application demands are needed to stimulate consumption. In the existing LED chip production lines, LED production lines can be directly converted to Mini LED production lines with just the addition of a welding furnace. However, the production capacity for Mini LED is still relatively low.”
Direct display screens are still in the research and development stage. Industry insiders have indicated that samples are expected to be launched around the end of 2021. This type of screen is still about five years away from mass production and will take at least ten years to fully replace mainstream home displays.
Huaxing Optoelectronics stated to Caijing: “Most of the technical challenges of Mini LED have been overcome; the most pressing issue for mass production is establishing a mature supply chain, which entails high trial-and-error costs.”Currently, Huaxing Optoelectronics is collaborating with upstream chip leader San’an Optoelectronics to jointly solve the challenges of large-scale production processes.
The LED industry chain is divided into upstream chip manufacturers, midstream packaging manufacturers, and downstream application companies. Since 2009, the government has heavily subsidized LED chip manufacturers, leading to an influx of capital into the industry, resulting in excess capacity in the upstream sector and a gradual decline in LED chip prices. Midstream packaging companies have also faced price wars due to capacity expansion, with some small and medium-sized manufacturers being eliminated, leading to increased industry concentration. Downstream application companies face similar situations.
If Mini LED is mass-produced in the future, costs will pose a challenge for midstream packaging manufacturers. Currently, only the “mass transfer” (also known as “large-scale solid crystal”) process can break through the cost limits of conventional processes. Chen stated: “Mass transfer equipment is currently being mass-produced in Japan and Taiwan, with a machine costing between 5 million and 8 million yuan. The entire production line requires nearly ten million yuan. Before Mini LED commercialization, midstream packaging manufacturers are still in a wait-and-see state regarding their investment in mass transfer technology.”
“The industry is currently waiting for Apple to launch Mini LED products. Once there is demand, there will be a market. Everyone hopes that Apple will lead the market and drive real terminal demand,” Chen said.
This article was originally published in the December 21, 2020 issue of Caijing magazine.
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