Korean display corporations that once dominated over 90% of the global organic light-emitting diode (OLED) panel market are facing a threat to their monopoly from the emergence of BOE and CSOT, cultivated by the Chinese government. BOE and CSOT have made substantial investments in research and development to break the conventional belief that 'Chinese OLED lacks quality,' and analyses indicate that the technology gap has narrowed in the 2020s.
Recently, Chinese display corporations have provocatively claimed that their OLED technology for smartphones is superior in terms of thickness and brightness compared to Samsung Display, a leading Korean player. In the midst of this, Samsung Display has revealed a significant 'blow.' The company showcased its polarizer-free display, known as on-cell film (OCF)-based OLED technology, at the Mobile World Congress (MWC) 2025 in March of this year.
◇ OCF advances mobile OLED to the next level
Generally, OLED displays have a characteristic where the quality decreases when external light enters the panel, contacts the electrodes (electronic circuits) inside, and reflects back. To prevent this, a polarizer, which is typically an opaque plastic sheet, is attached to the panel to minimize reflection. However, as light passes through the polarizer, brightness decreases by over 50%, leading to a drop in light efficiency.
In response, Samsung Display has embarked on developing new technology, noting that if a color filter is used instead of a polarizer, colors can be expressed more vividly while reducing power consumption. In 2021, the company became the first in the industry to commercialize this technology, branded as 'Ecosquare OLED' based on OCF.
By attaching a black pixel defining layer (BPDL) and color filter to the panel instead of a polarizer, the method increases light transmittance while reducing power consumption and thickness. The developed panel stack structure prevents external light reflection and enhances light transmittance by 33%, potentially saving power consumption by up to 25%. While the complexity of the process increases, Samsung Display has quickly stabilized yield rates due to its extensive OLED production expertise.
This technology was first applied to the foldable display of the Samsung Electronics 'Galaxy Z Fold 3', and is also credited with enabling the implementation of the under panel camera (UPC) technology, which places the camera module beneath the panel. A Samsung Display official noted, "As the light transmittance of the display improved, more light was delivered to the camera module at the bottom of the panel, allowing us to secure UPC-based technology."
◇ China also joins the OCF competition, Samsung responds with next generation
After Samsung Display first commercialized this technology in 2021, Chinese corporations began their own research and development into similar technology. However, to date, Samsung Display's mass production quality is still regarded as the best. This is evident from its supply achievements. Samsung Display's OCF-based OLED is exclusively supplied to devices including the Galaxy Z Fold 3, Galaxy Z Fold 5, Xiaomi Mix Fold 3, Vivo X Fold 2, and Google Pixel Fold.
Samsung Display is also expanding the application of OCF technology to laptops. At the Consumer Electronics Show (CES) 2025 held in Las Vegas this January, Samsung Display unveiled the Lenovo 'ThinkBook Plus G6 Rollable,' which is equipped with OLED. This product supports a 14-inch screen with a 5:4 aspect ratio in rolled-in state and utilizes a 16.7-inch screen with an 8:9 aspect ratio in rolled-out state. The OLED, previously hidden beneath the keypad, expands vertically.
At MWC 2025, the plan is to further develop this technology to improve brightness and widen the gap with Chinese corporations. The OCF-based OLED that Samsung Display will unveil is said to have a screen brightness 1.5 times higher than existing OLED panels while reducing thickness by about 20%. Notably, the maximum screen brightness reaches 5000 nits (1 nit is the brightness of one candle), making it one of the highest in the industry.
A source familiar with Samsung Display stated, "In terms of power consumption, viewing angles, and reflection characteristics, Samsung Display's OLED panels maintain a competitive advantage over rivals," adding that "the next generation of OCF OLED technology to be unveiled at MWC 2025 will address the brightness weakness of OLEDs, capturing demand not only from major clients like Apple but also from PC manufacturers hastening the adoption of OLED panels."