LG Display held a 'display technology briefing session' on March 27th at Magok LG Science Park. Beginning with defining displays, the company has explained future progress directions and display technology leading to cathode ray tube (CRT), plasma display panel (PDP), liquid crystal display (LCD), organic light emitting diode (OLED), and micro light emitting diode (LED). In addition to Vice Chairman Han Sang-Bum, CTO Kang In-byung, Vice President Oh Chang-ho of TV business, Managing director Yun Soo-young of Research Center (Director), and Lee Bo-yeol R & D strategy official (Executive Director) attended the event.
THELEC summarized the contents that LG Display wanted to convey through the technical briefing session in five ways.
1 Samsung QLED is LCD after all
He emphasized that the complex terms such as LCD, LED, OLED, QD OLED, and QLED should be simplified. Apart from OLED, LCD is the key to TV display. The TV brand, which Samsung Electronics has named as QLED, was explained to be a Quantum Dot Enhancement Film (QDEF) attached to an LCD panel. In other words, QLED is equal to QD LCD technology. QD OLED, which Samsung Display is preparing for its next-generation TV, is also a kind of OLED. He repeatedly emphasized that OLED is dominant and LG Display is leading the market by starting earlier.
Regardless of the technology, Samsung emphasized that it was more important to supply the best (in terms of price and performance) products to consumers. Samsung Electronics vice chairman Yun Bu-keun said, "It is not important whether it is self-luminous (OLED) or LCD, but it should be able to provide the best performance without imposing a price burden on consumers."
2 For 8K, OLED is advantageous
LG Display first released 8K OLED panels in January last year. At that time, the company said, "The 8K implementation is easy because OLEDs have relatively low brightness degradation due to the reduction of the aperture ratio (the area ratio of the actual light). LCDs are non-luminescent, which means that as the pixel size gets smaller, the transmittance is rapidly reduced to ensure performance with the backlight. This can dramatically increase the material cost and power consumption of the backlight."
At the technical briefing, Oh Chang-ho VP said, “OLED is more advantageous than LCD as resolution increases. The higher the resolution, the lower the aperture ratio. OLEDs do not increase the power consumption when the screen size is constant. The difference in power consumption due to full HD and 8K resolution in 88-inch OLEDs is not big."
3 8K OLED panel made with a backlight
In the industry, LG Display is expected to adopt the top emission method in 8K OLED to secure the aperture ratio. Engineers and academics all agreed to this notion. The whole light emission is a method in which the light of the organic layer is bypassed to the side of the substrate without passing through the substrate. The loss is reduced because light does not pass through the substrate. The 8K OLED, however, uses the same bottom emission. The company succeeded in upgrading OLED panels based on their existing designs.
Yoon Soo-young Director said, "It is difficult to implement 8K OLED when it is not front-emitting. Because competitors came up with the same idea, only a fraction of the content were released at the International Information Display (IMID) exhibition last year. We plan to use the entire luminescence in inkjet (solubilized process, solution process) because we derived the backlight performance to the fullest extent.”
4 Transparent OLED mass production line to be established in Paju
LGD should expand its use of OLED. The company’s OLED panel shipments last year were only 2.9 million units. The portion the company occupies within the total TV market (around 220 million units) is still low. To conquer the B2B market, LG Display plans to build a transparent OLED panel production line with 40% transparency and full HD resolution in Paju this year. The main product’s screen size is 55 inches. Depending on the customer, 65 inch products can be supplied.
Transparent OLED panels were achieved through a national policy project for transparent flexible displays that implemented a 77-inch, UHD (3840 × 2160) resolution, transmittance of 40%, and a curvature radius of 80R (radius of 80mm radius). The rollerblue TV technology has also been developed from this project.
5 Applying inkjet on IT panel first
The solution process is a technique of placing an OLED light emitting material in the form of a solution on a substrate by inkjet printing technique. It is more economical than the vacuum evaporation method of vaporizing organic materials in a vacuum chamber. It is possible to drastically lower the price of OLED panels.
"We can make backlit 8K OLED panels." said VP Kang In-jin and added, "We are preparing to apply inkjet printing to IT panels. IT panels should also go beyond the 8th generation, and we will further develop the technology." This means that, as with transparent OLED panels, monitors, notebooks, and other OLEDs are not yet fully integrated.