Advancing Emissive Displays at Fuzhou University

Abstract

FROM CATHODE RAY TUBES (CRTS) TO OLED OR MICROLED, emissive displays capture the imagination of consumers and developers who want high-performance televisions or professionals who need the most accurate display for mastering films and performing scientific research. With illumination and lighting control at the individual pixel level, emissive displays can reproduce near-perfect black levels—allowing for movement of images with minimal blur and providing outstanding detail and contrast as well as deep, rich colors. However, these displays tend to carry higher price tags than their LCD counterparts, which can limit their audience. Also, current emissive displays are mostly passive, with limited user interactivity.

At institutions such as Fuzhou University (FZU), ongoing research is advancing the state of the art in emissive displays, adding rich interactivity and advanced AI features, while also bringing the cost and complexity down to make these next-generation display devices more accessible. Founded in 1958 and located in Fujian, China, FZU is one of the key national universities selected for the Double First-Class Initiative, a commitment by the Chinese government to enhance China's higher education and foster international competitiveness.

FZU's history in electronic display research dates to its pioneering work in oxide cathode emission in CRTs in the late 1970s. University researchers expanded into field emission displays in the late 1990s and early 2000s and then into flat panels, including LCD TVs, from the mid-2000s. By 2012, FZU was leading the way in Chinese flat-panel TV development via the Haixi Collaborative Innovation Center for New Display Devices and Systems Integration. This project united 11 institutions, including universities across mainland China, Hong Kong, Taiwan, and Singapore, plus display industry leaders such as TCL, AOC, Tianma, Hisense, and Sanan Optoelectronics. Each collaborated with the goal of refining the processes and technologies used in end-to-end display development.

In 2019, FZU allied with the Chinese Academy of Sciences (CAS) to establish the China (Fujian) Science & Technology Innovation Laboratory for Optoelectronic Information, also known as the Mindu Innovation Lab. It is one of four provincial laboratories focusing on advanced photonic materials, new display and lighting technologies, and high-speed optical communications. The lab expanded the university's research into flexible, 3D, and microLED display technologies. FZU's display research program currently includes 25 professors and researchers and approximately 300 students.

Qun “Frank” Yan joined FZU as a distinguished professor in 2016. Previously, he worked in senior research roles at Plasmaco, Panasonic, and Changhong Electric Group, where he served as the chief scientist until 2016. Yan is currently president elect of the Society for Information Display (SID) as well as director of SID China and an authoritative expert in the field of visual display devices. He received the SID Special Recognition Award in 2013 and SID Fellow in 2017 for his outstanding contributions to display technology—the only scholar born in mainland China to hold both distinctions. He has published more than 200 papers and 40 conference presentations in his field of expertise and holds more than 60 patents.

Many of Yan's early patents were related to plasma display panel (PDP) technology and were instrumental in bringing PDPs into wide-scale production. His innovations continued as technologies evolved. “These newest patents will be a core part of innovation in microLED technology, including the know-how for mass production, and some patents will be key IPs for a newly established company by my research group,” said Yan.

Yan saw the potential of microLED as a successor to plasma and decided to move to academia to help develop both the technology and people who could bring it to market. He chose FZU because of its comprehensive program for display research, excellent facilities, and collaborative research environment. He guides both undergraduate and graduate students in display technology and related interactive systems.

“Having witnessed the rise and decline of PDP, I was convinced that microLED represented the true ‘third wave’ of emissive displays, but recognized that its maturation would require sustained, fundamental research and a new generation of skilled engineers,” said Yan.

FZU offers a state-level display research laboratory within its College of Physics and Information Engineering. The lab comprises more than 30 researchers and 300 graduate students. Yan's team includes two professors, four engineers, and more than 30 graduate students whose research focuses on highly integrated semiconductor information display (HISID) (Fig. 1).

HISID is a visionary concept introduced by Yan to transform conventional screens into multifunctional, interactive information terminals. Rather than simply presenting static images, a HISID panel integrates display, sensing, communication, and computing directly within a microLED–based module.

At its core, HISID leverages heterogeneous device integration to embed driver integrated circuits (ICs), memory, processors, sensors, and antennas onto the display substrate, frequently referred to as a system-on-panel. By mounting these components within or immediately behind the pixel array, HISID eliminates bulky external electronics, thereby reducing interconnect length (minimizing latency) and enabling ultra-thin, ultra-lightweight form factors.

“A crucial enabler [of HISID] is advanced mass-transfer and packaging technology,” said Yan. “For instance, laser-induced forward transfer (LIFT) has emerged as a practical method to place microscale LEDs onto active backplanes with high accuracy and throughput—addressing one of the greatest manufacturing hurdles for microLED displays and paving the way for HISID integration.”

Developing HISID has required multiple advancements in both panel and component device technology. MicroLED chips must be manufactured in the single-digit micron range, delivering extremely high pixel densities (greater than 1,000 ppi). Because each emitter occupies only a tiny fraction of a typical pixel cell, the remaining area can host micron-scale ICs and sensors, realizing true system-on-panel capabilities.

MicroLEDs outperform incumbent competitive technologies by delivering exceptional brightness (several thousand nits) and energy efficiency, with lifetimes measured in tens of thousands of hours. These attributes are particularly critical for applications demanding daylight visibility or always-on operation.

With nanosecond-scale switching, microLEDs support ultrahigh refresh rates and can double as visible-light communication (Li-Fi) transmitters, enabling high-bandwidth data links through the display itself. This dual role—display plus optical channel—forms a cornerstone of HISID's bidirectional interaction paradigm.

HISID aspires to generate real 3D light fields that float in space, empowering users to engage naturally—no headgear required. By combining volumetric capture systems, custom light-field codecs, and HISID panels capable of directional light emission, the technology promises glasses-free 3D experiences and immersive “video-as-game” interactions. Integrated spatial sensors (e.g., gesture or eye tracking) further enable AI-driven personalization and feedback loops.

Placing millions of microLEDs with near-perfect accuracy remains a yield-critical process. While LIFT and self-assembly techniques show promise, achieving consumer-scale cost targets is still ongoing. Integrating diverse components (e.g., driver ICs, sensors, and antennas) requires cutting-edge 2.5D/3D packaging and precise interconnects to ensure signal integrity and thermal management.

High-brightness operation and densely packed electronics necessitate novel microscale heat spreaders or substrate solutions to avoid color shifts or reliability issues. Fabricating red, green, and blue microLEDs with matched performance is difficult; quantum-dot (QD) layers or phosphor color conversion can help, but they introduce their own efficiency and longevity considerations (Fig. 2).

Realizing HISID's interactive potential demands new operating systems, middleware, and content standards to orchestrate sensing, rendering, and communication—efforts just beginning in industry consortia.

Yan's research group has made significant strides in microLED mass transfer and bonding technologies (Fig. 3). “One of the most important issues is to decrease the time necessary to evaluate a microLED array to identify any defects before mass transfer and fast bonding,” said Yan. “This will help reduce the effort involved in repairing bad microLED elements after bonding (which can take quite bit of time). We also developed unique bonding techniques that can get very reliable bonding, even if the alignment between microLED arrays and TFT electrodes is not perfect.”

The complexity of developing such a display can be overwhelming. Even the most promising ideas do not always work in practical applications. Issues such as limitations in resources and investments—even geopolitical issues—may lead to delays.

To address these challenges, Yan is developing a blockchain-based innovation community collaboration platform that aggregates market signals, investment, ideas, and expertise. All stakeholders (investors, researchers, and manufacturers) register on the platform, where project proposals are evaluated and ranked by community consensus and AI-driven metrics.

An AI algorithm dynamically aligns funding sources, fabrication facilities, technical teams, and market opportunities, accelerating decision-making and reducing inefficiency and misallocation. The blockchain's ledger records project milestones, funding transactions, and IP registrations—providing both confidentiality for research and development (R&D) data and verifiable audit trails for technology transfer. Objective performance indicators and peer-review feedback guide investment and partnership decisions, minimizing bias and enabling high-integrity project evaluations.

By uniting capital, capabilities, and ideas on a single, tamper-proof platform, and leveraging AI to optimize matches, Yan feels that this approach should help to streamline innovation, de-risk investment, and ultimately accelerate the commercialization of next-generation display technologies.

Yan sees HISID as a shift from passive screens to interactive, intelligent terminals. Powered by microLED's superior optoelectronic properties and enabled by advances in heterogeneous integration, HISID promises immersive 3D light-field displays, bidirectional AI-driven interaction, and potentially unprecedented form-factor flexibility. While significant manufacturing and ecosystem challenges remain, the rapid pace of microLED innovation—validated by mass-transfer breakthroughs and growing industry consortia—points to HISID becoming a cornerstone of next-generation information networks and rich-media experiences.

The FZU research team, as well as the greater global research community, continues to refine HISID's building blocks. We may very well stand on the cusp of a new era in display technology—one in which every wall, window, and wearable device could become a dynamic portal for interactive content, communication, and sensing.

Regarding other promising technology, Yan mentioned possibly combining multiple display technologies into one hybrid display, such as microLED with OLED or microLED with QLED. Work on display integration with sensors, photovoltaics, thin-film batteries, and micro-size ICs could bring advanced displays to more environments and to a wide variety of form factors.

Funding at any university is always a challenge, even when government grants and private support provide a significant boost. FZU's display research program has been fortunate to receive support based on its research reputation, with TCL, Hisense, and Tianma as some of the school's top benefactors. The school also collaborates with organizations such as GlobalFoundries. GlobalFoundries and FZU established a joint research agreement to explore advanced complementary metal-oxide semiconductor (CMOS) backplane integration for microLED arrays.

Through these industry partnerships, FZU aligns their academic research with industry needs—securing in-kind support (equipment, materials, and process access), providing their students with real-world training, and accelerating the translation of laboratory breakthroughs into commercial display products.

Yan attributes the school's ongoing progress and success to its tight collaboration with display companies for joint development projects strongly funded by the government. This has placed FZU in a position to concentrate on cutting-edge research rather than fundraising.

FZU and Yan's research group follow a learner-centered, practice-driven philosophy that prepares students for both academic and industrial careers (Fig. 4). In the program, Yan says they emphasize five core competencies:

By combining project-based coursework, lab rotations, and industry placements, FZU ensures that graduates not only master display-technology fundamentals but also leave with the practical skills and professional confidence required to excel beyond academia.

Most of Yan's past students have gone on to R&D roles in high-tech companies, including display-related companies in China. Some of his doctoral students have chosen to continue in academic positions at universities, mentoring and training the next generation of display researchers and engineers. Other FZU graduates choose to continue their research in government positions.

As for Yan, besides day-to-day research, conferences, and lectures, he prioritizes exercise and encourages his team to exercise together.

He has several technological milestones—from significant advancements in PDP technology and processes to microLED breakthroughs related to high-throughput mass transfer, hybrid driver integration, and in-pixel sensing. In 2017, Yan established the International Conference on Display Technology (ICDT) in Fuzhou, China, which has grown into one of SID's marquee events.

Yan takes pride in mentoring the next generation of display professionals and sees a bright future for FZU. “I think the collaboration with other universities, research institutions, and display companies both domestically and internationally, plus attracting the best talent in display research is the most important path for Fuzhou University to keep advancing the study of display technologies. By combining robust partnerships, a world-class talent pipeline, and translational research infrastructure, Fuzhou University will cement its leadership in next-generation display technologies and nurture the innovations that define the future of interactive, immersive information displays.”