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Visionox and the research team of Professor Lian Duan at Tsinghua University jointly presented research results demonstrating OLED efficiency improvements through ViP™ (Visionox intelligent Pixelization) technology at ICDT 2026 (International Conference on Display Technology). This presentation is particularly noteworthy as it marks the first co-authored paper between Visionox, which has led the ViP™ process innovations, and Prof. Lian Duan’s group, which developed the pTSF (phosphor-assisted TADF-sensitized fluorescence) mechanism and contributed to its mass production adoption.

OLED panels fabricated using the fine metal mask (FMM) process have a pixel aperture ratio (APR) of only 20–30%. This narrow emitting area forces high current densities through the device, fundamentally accelerating efficiency roll-off and material degradation. On large-area substrates of Gen 8 and above, mask sagging makes precise alignment increasingly difficult, creating serious yield challenges for producing high-resolution OLED panels at 400 ppi and beyond.

The ViP™ technology, disclosed by Visionox in May 2023, patterns pixels via photolithography, enabling an APR exceeding 50%. Furthermore, unlike FMM, it allows the common layers of each R, G, and B sub-pixel — including HIL, HTL, EBL, ETL, and others — to be designed and optimized in complete independence.

The research team systematically investigated the efficiency-improvement effects of ViP™ technology along three axes: materials, layer thickness, and emission mechanism. In the FMM process, the hole transport material (HTM) has traditionally been selected based on the performance requirements of the blue device. With ViP™, however, the common layers for each sub-pixel can be chosen independently to match their respective emission characteristics.

Diagram showing the structural changes of ViP™ OLED devices from Reference to Phase 1 and Phase 2, illustrating the independent optimization of common layers (CAT, CPL, ETL, EBL, etc.) for each RGB subpixel

Structural optimization phases of ViP™ OLED devices revealed by Visionox and the Tsinghua University research team. It overcomes the limitations of FMM by independently designing the common layers of each subpixel to prove efficiency improvements. (Source: Visionox & Tsinghua University)

A comparison of three HTM materials sharing the same HOMO level (−5.2 eV) but differing in hole mobility revealed that a red device based on an HTM with significantly lower mobility degradation under high electric field conditions achieves an efficiency roll-off (G16/G255) of 101% — effectively zero — at high luminance, while extending LT95 lifetime by 48% relative to the reference device.

Two-stage optimization effects were quantitatively verified through SETFOS optical simulation. In Stage 1, individually tuning the cathode (CAT) and capping layer (CPL) thicknesses for the R and B devices alone improved white efficiency by 5%. In Stage 2, further optimizing the HTL, EBL, and ETL thicknesses for each of R, G, and B added an additional 9% (green), 3% (red), and 2% (blue) improvement. The combined white efficiency gain from both stages exceeds 7%, a magnitude comparable to a full year’s efficiency progress achievable through materials innovation (typically 5–10%).

ViP™ enables device structure optimization tailored to each emission color. A blue device based on the pTSF mechanism achieves theoretical efficiency 1.6–2.5× higher than that of a TTA (triplet-triplet annihilation) fluorescent device. Applying the pTSF mechanism across a white panel can boost overall efficiency by up to 55%. However, in FMM-based mass production lines, the HOMO/LUMO energy levels of the HTM and EBM required for pTSF green and pTSF blue pixels are mutually incompatible, making it practically impossible to raise efficiency within a single panel. ViP™ resolves this structural barrier and opens the path to integrating both a pTSF green device and a pTSF blue device within a single panel.

This study suggests that as ecosystem collaboration deepens between material suppliers and equipment manufacturers, the efficiency gains enabled by ViP™ technology will accelerate further. For next-generation applications demanding high resolution and low power consumption — large-format IT panels (monitors, laptops), AR/VR headsets, and automotive displays — the ViP™–pTSF technology combination is poised to emerge as a core source of differentiated competitive advantage that FMM-based mass production lines cannot replicate.

Changho Noh, Senior Analyst at UBI Research (chnoh@ubiresearch.com)

2026 Medium & Large Size OLED Display Annual Report

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China’s display industry has set a milestone beyond leading global production volume, advancing toward self-reliance in core material technologies. Tsinghua University and Visionox officially announced the successful mass production of Phosphor-assisted Thermally Activated Delayed Fluorescence Sensitized Fluorescence (pTSF) technology—a fourth-generation OLED light-emitting technology—at a jointly hosted technology forum held at Tsinghua University in Beijing on the 7th. They also unveiled achievements utilizing this technology. This announcement is considered a significant event, to announce that next-generation material technology, previously confined to the realm of academic possibility, has been successfully introduced into actual mass production lines and entered the commercialization stage.

The Phosphor-assisted Thermally Activated Delayed Fluorescence Sensitized Fluorescence (pTSF) technology developed by the joint research team is a fourth-generation solution that resolves the ‘Impossible Triangle’ challenge faced by conventional OLEDs—the difficult task of simultaneously achieving high efficiency, long lifetime, and high color purity. This technology operates on the principle of maximizing efficiency and lifespan by establishing a unique triple energy transfer system composed of a TADF host, a phosphorescent sensitizer, and a fluorescent emitter. It captures internal energy without loss and rapidly transfers it to the emitter.

Particularly noteworthy at this forum was the reconfirmed mass production performance data for the Green Phosphor-assisted Thermally Activated Delayed Fluorescence Sensitized Fluorescence (pTSF) device. This device garnered significant academic attention at ‘SID 2025’, the world’s largest display conference, held last May.

Visionox’s low-power ‘Product A’ (left) and ultra-high image quality ‘Product B’ (right) pTSF OLED panels demonstrated at SID 2025 (Source: SID 2025)

Visionox has disclosed the performance of two panel types (Product A, Product B) manufactured on its G6 mass production line. The low-power specialized model ‘Product A’ reduces power consumption by 12% compared to existing phosphorescent OLED products and improves lifetime (LT95) by over 15%. Furthermore, Product B’, an ultra-high-definition specialized model, achieved a color reproduction rate exceeding 99.5% for both DCI-P3 and AdobeRGB color gamuts, demonstrating significant progress in image quality. This was achieved by applying the research team’s independently developed Exciplex host and optimizing the device structure to enhance energy transfer efficiency, while also reducing the usage of expensive dopant materials by approximately 10%.

The newly unveiled technology is expected to be brought to Honor’s Magic series or Nubia’s latest models. Honor and Nubia are longstanding core partners of Visionox, with a history of being the first to adopt Visionox’s new technologies (such as high refresh rates and UDC) in their flagship lineups. Therefore, it is highly likely they have also secured priority supply for this 4th-generation technology.

Building on the success of mass-producing these green phosphors, Tsinghua University and Visionox have outlined a roadmap to expand the application of Phosphor-assisted Thermally Activated Delayed Fluorescence Sensitized Fluorescence (pTSF) technology into the red and blue phosphor domains. The research team is currently focusing on securing the stability of red MR emitters and blue auxiliary phosphors, which are considered major technical challenges. Through this, they plan to achieve complete independence in material technology across the entire OLED spectrum. The Chinese side views this achievement as a significant turning point for the Chinese display industry, marking its transition from a follower to a technology leader.

Visionox’s high-efficiency pTSF OLED device displayed at SID 2025 (Source: Visionox)

Changho Noh, Senior Analyst at UBI Research (chnoh@ubiresearch.com)

2025 OLED Emitting Materials Report Sample

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