Demystifying AMOLED: Innovations in LTPO Backplanes and Colorization Technologies

  AMOLED display technology has become a mainstream choice in the small and medium-sized consumer electronics sector due to its self-emissive nature, high contrast ratio, wide color gamut, and flexible bendability. Compared to traditional LCD screens that rely on a backlight module, each pixel in an AMOLED screen emits its own light, consuming almost no power when displaying black. This results in a simpler structure, wider viewing angles, and significantly faster response times. Its core components include the backplane, OLED light-emitting layer, and thin-film encapsulation (TFE).

  Backplane technology is crucial for achieving high-quality AMOLED displays. Early amorphous silicon (a-Si:H) TFTs were inadequate for effectively driving OLED pixels due to their low mobility and insufficient stability. The industry currently widely adopts low-temperature polycrystalline silicon (LTPS) TFT and  (Oxide) TFT backplane solutions. LTPS offers high carrier mobility, making it suitable for driving light emission, while Oxide TFTs exhibit extremely low leakage current, which helps maintain pixel state.

  Apple's introduction of LTPO technology in 2018 combined the advantages of both, integrating LTPS and IGZO TFTs to enable dynamic refresh rate adjustment, significantly reducing screen power consumption. This has since become a signature technology for high-end AMOLED displays.

  To address the issue of "burn-in" caused by the differing lifespans of organic materials, the industry has proposed several colorization solutions.

WOLED (White OLED) combines a white light source with color filters (CF) to derive the three primary colors, ensuring consistent aging rates for RGB sub-pixels. Another approach is blue OLED + quantum dot color conversion (QD-CC), which uses blue OLED to excite a quantum dot film to emit red and green light.

  Additionally, a multi-layer tandem structure stacks multiple light-emitting units via a charge generation layer (CGL), enhancing brightness while extending device lifespan. These technologies have further led to mainstream mass-production solutions such as WOLED and QD-OLED.

  MicroLED is regarded as a major direction for next-generation display technology. It utilizes inorganic materials such as gallium nitride to create micron-scale LED light-emitting units, offering long lifespan, high efficiency, and extremely high brightness, all without the need for a backlight or color filter system. It holds significant potential in fields like AR/VR. However, the technology still faces industrialization challenges related to the precision and cost of mass transfer. Despite these bottlenecks, its performance advantages are substantial. Whether through the ongoing optimization of LCD modules, iterations in AMOLED technology, or advances in MicroLED, the display industry continues to drive progress in visual experiences, offering a rich array of choices for various customized LCD screens and new display requirements.

About CNK

  Founded in Shenzhen in 2010, CNK Electronics (CNK in brief) expanded the world leading factory in Longyan, Fujian in 2019. It is a specialized and innovative enterprise specializing in the design, development, production and sales of display products. CNK provides customers with a full range of cost-effective small and medium-sized display modules, solutions, and services with excellent quality worldwide. Oriented in technology and high quality, CNK keeps sustainable development, works to offer customers  better and stable services.