In-depth Report On The LCD Panel Industry

LCD panels are still the mainstream of the display field in the next 5-10 years

The replacement of mainstream display technology from picture tubes to liquid crystal panels has taken about 50 years. In the last round of display technology replacement, the main driving force of emerging technologies is the increasing consumer demand of consumers, and the core of the commercialization of emerging technologies is still price.

We believe that with the support of technologies such as Mini-LED backlighting, LCD panels will be able to meet consumers' new demands for high-definition and large-screen displays. Considering that the yield and cost of emerging technologies are difficult to solve in the short term, it is expected that LCD panels will remain the mainstream technology in the display field in the next 5-10 years.

 Rise: From CRT to Liquid Crystal Display Technology

With the development of material technology, display technology has also developed from the original cathode ray tube display technology (CRT) to flat panel display technology (FPD), and flat panel displays have also extended to plasma display (PDP), liquid crystal display (LCD), and organic light emitting Diode display (OLED) and other technical routes.

The development of display technology can be divided into three stages. Take TV as an example.

The first stage, the CRT era of the 20th century: In 1897, the world's first CRT was born. The phosphor on the inner surface of the screen was excited by electron beams to display images, which realized the conversion of electrical signals to light output. With the improvement of technology and technology, the industrialization of CRT technology began in the 1950s, and black-and-white CRT TVs and color CRT TVs became the most important display devices in life. Although CRT production costs are low and limited by picture tubes, CRTs generally can only be 34 inches in size, which cannot meet the increasing demand for large sizes.

The second stage, the alternate era of the 1990s: rear projection technology, plasma technology, and liquid crystal technology are in parallel. The size of traditional CRT TVs cannot meet the needs of consumers. Around 1990, manufacturers began to try various technologies to achieve larger display effects. The rear projection TV is based on the principle of projection and emission. The projector is installed at the bottom of the fuselage, and the signal is projected to the back of the translucent screen for visualization through reflection.

Although rear-projection TVs had the advantages of large size and high brightness at the time, problems such as the lifespan of the bulbs were gradually eliminated due to their heavy fuselage. The plasma TV uses a plasma tube as a light-emitting element, injects mixed gas between two ultra-thin glass plates, and uses phosphors to emit light by applying a voltage. Although plasma TVs have high screen definition, they cannot be resolved due to the screen burn-in phenomenon and have not become the mainstream of next-generation displays.

The third stage, the LCD era of the 21st century: Early LCD TVs were illuminated by CCFL tubes inside the TV. Due to the limitation of the volume of the tubes, the thickness of the TV was not ideal. After 2000, with the improvement of liquid crystal technology, LED light-emitting diodes have been used as backlight sources to reduce the size of LCD TVs. At the same time, the LED backplane has obvious advantages in power consumption, which is more than 30% lower than the power consumption of traditional LCD TVs.

Since 2005, the cost of LCD TVs has fallen sharply, and the price war among manufacturers has become more intense at that time, and LCD TV prices have fallen sharply: According to CNN News, 32-inch LCD TVs have fallen sharply from US$1,566 in 2005 to US$580 in 2008. The price of a CRT TV of the same size is comparable. In the same year, LCD TVs accounted for more than 50% of shipments in my country for the first time, becoming the mainstream technology in the display field.

It can be seen from the evolution of display technology that high-definition, large-size, thinner (portable) have always been the main factors for consumer demand. The new generation of display technology not only needs to meet the needs of consumers at the time, sufficient performance advantages, and stability for long-term verification, but also needs to continuously reduce costs during the industrialization process to achieve a competitive price before it has the opportunity to replace the existing ones. Mainstream display technology.

Challenge: The development and bottleneck of emerging technologies

As we mentioned in the previous article, the needs of the display industry are mainly portability-flexibility, large size and high definition. At present, the emerging technologies explored by major manufacturers mainly include OLED, Micro-LED direct display and other technologies.

Although Micro-LED has a high display effect, it still takes time to achieve commercialization: Micro-LED is currently a research hotspot in the display industry, and it is also one of the most promising display technologies in the future. However, there are technical difficulties such as massive transfer, packaging and testing, full color, uniformity, etc., which are still in the research and development stage, and there are still a few years away from commercial mass production.

OLED technology has gradually realized commercial production and has begun to be applied to small-size fields such as watches and mobile phones. The full name of OLED is organic light-emitting diode. OLED uses self-luminous imaging and has the characteristics of low energy consumption, high contrast, flexibility and relatively simple process. At present, OLED displays are mainly equipped with smart phones with folding screens represented by active matrix AMOLED.

Due to other expenses such as depreciation and labor costs, there is still a certain price difference between AMOLED and LCD mobile phone panels: Data from Zhiyan Consulting shows that the yield of AMOLED needs to reach 80% and its cost may be lower than that of LCD. With the increase in yield, Trendforce predicts that the penetration rate of AMOLED mobile phones will rise from 31% in 2019 to 38% in 2021, and the penetration rate of AMOLED mobile phones is expected to exceed 50% in 2025.

Although OLED has begun to be used in small-sized devices, OLED will not be able to replace LCD screens and become the mainstream market in the next few years. There are three main reasons:

First, there are still larger technical barriers to OLED than the mature TFT-LCD. At present, the OLED manufacturing process does not have a unified mass production technology, and it is still necessary to continuously optimize the devices, equipment, and process flow, such as masks, vacuum evaporation machines: low-voltage heating and electron beam bombardment of the raw materials of each layer of OLED in the vacuum chamber Or laser heating method sublimates into atoms and molecules, and then passes through the mask to condense on the substrate to form a thin film. The higher the degree of precision of the mask, the more uniform the thickness of each layer of material is condensed, and the more precise the position of the three-color luminescent material vapor deposited on the same layer. Enlarged size production has greatly increased the difficulty of achieving the required precision, and the high requirements of production have made high-standard vacuum evaporation machines still "hard to find".

Second, the stability of the OLED panel is insufficient compared to the lifespan of the LCD panel. When the screen is used for a long time with high brightness, the sensitivity of OLED's self-luminous material characteristics to humidity and oxygen concentration will cause the performance of some sub-pixels to decline faster (half-life) than TFT-LCD, and display sub-pixels with different colors The speed of attenuation is not consistent, which may cause black screen, blurring or burn-in of the OLED that is used for long-term high-intensity. Although the use of small-screen mobile phones and other consumer terminals has no obvious impact, the display application of OLED panels in large-size devices still requires technological updates and iterations, which cannot be realized in the short term.

Third, OLED lacks a cost competitive advantage over LCD. According to data from IHSMarkit, the current mainstream market is the mainstream panel size of 49 to 60 inches. Taking a 55-inch ultra-high-definition OLED as an example, the manufacturing cost of an OLED panel with only a 60% yield rate is about 2.5 times that of a TFT-LCD of the same size. In the short term, due to the high technical barriers of the two key steps of sublimation purification and vacuum distillation, OLEDs cannot quickly increase the yield rate.

For large-size OLED panels, even if the yield rate reaches more than 90%, the manufacturing cost is still about 1.8 times that of TFT-LCDs of the same size. Taking into account that depreciation is also an important factor in cost, the OLED factory has been depreciated, and the cost gap of 60% yield is still 1.7 times, and the yield is reduced to 1.3 times in the case of 90%.

Although OLED has a capacity expansion trend in the field of small and medium-sized screens and has performance advantages, in the large-size field, compared with TFT-LCD, OLED still has technology and capacity limitations within 3-5 years. Samsung and LGD, who have invested in this technology on a large scale, will have the future The total shipment volume does not exceed 10% of the global TV panel demand, and there is still a big gap with the TFT-LCD shipment volume.

New opportunities: Mini-LED backlight technology brings growth opportunities to LCD

Compared with OLED technology, LCD technology has obvious advantages in terms of cost and life; it has a small difference in color gamut, resolution, and power consumption, and has disadvantages in contrast and motion image blur. Although OLED has a variety of characteristics with excellent image quality, and its self-luminous display technology is recognized as the new development direction of the future display industry, the current material stability and packaging and sealing technology of OLED need to be improved, compared with the mature traditional backlight Source LCD, the cost still has room for further sinking.

The appearance of Mini-LED changed the passive situation of LCD. The addition of Mini-LED backlight technology has greatly improved the performance of LCD, and directly competes with OLED in all aspects of non-flexible display performance: Because Mini-LED has local dimming technology, it can dynamically adjust the overall picture. Light can achieve high dynamic contrast and wide color gamut display. Through special packaging structure and technology, the light angle can be increased, the halo effect can be reduced, and the terminal can achieve near-zero OD design with uniform self-mixing effect, and the whole machine can be thin and light. It can achieve the same effect as OLED display.