Technical / Research

Researchers from the University of St Andrews, led by Prof. Ifor Samuel, have designed an OLED based communication device that achieves a record data rate of 3.2Gbps.

To realize this achievement, the researchers developed high-speed red, green and blue emitting OLED devices, on a single substrate. Using wavelength division multiplexing (WDM), the three OLED devices are emitting at the same time. By selecting fluorescent materials with nanosecond emission lifetimes and little overlap between their emission spectra, the researchers achieved a -6b dB electrical bandwidth of over 100 Mhz. 

Researchers from Durham University have used a unique molecule to create TADF emitters with better triplet harvesting, and thus extended lifetime. The fused indolocarbazole-phthalimide molecules offer rigidly planar charge-transfer and can maintain their stability and efficiency over time, even in high-stress conditions.

The researchers say that the new molecules break all our current ideas about excited states in OLED emitters and the researchers developed a new model linking molecular bonding patterns leading to the breaking of molecular pi-conjugation in the excited state. 

Researchers at Korea's Gachon University, in collaboration with InnoQD and researchers from Chungbuk National University, have developed a new QD-OLED patch that can encourage hair growth. The patch can also measure heart rate at the same time.

The researchers used a flexible OLED device, and covered it with quantum dots that emit near-infrared (NIR) light. The OLED device is a tandem blue OLED device, that offers a high light output. The researchers say that when attached to the head, the patch encourages hair collicle cell growth, with a measured improvement of 23% in hair growth.

Researchers from Seoul National University (SNU), in collaboration from colleagues from Samsung's SAIT institute, have identified a critical mechanism behind the performance degradation of OLED devices, the interfacial exciton-polaron quenching mechanism.

The researches have theoretically proposed a mechanism where excitons in the light-emitting layer are quenched by the accumulated charges at the interface. They followed with with experiments that have independently observed this phenomenon, identifying three key factors: interfacial barrier, exciton-polaron distance, and exciton lifetime. 

Researchers from Korea's UNIST institute, together with colleagues from Sungkyunkwan University have developed a new OLED intermediate layer material (with a highly unusual structure, twisted EBMs with anisotropic molecular arrangements) that significantly improves the brightness, efficiency and lifetime of blue phosphorescence OLED devices.

The researcher report that the new materials enable to reduce the operating voltage of the OLED display, thus enhancing the power efficiency by 24% and the operational stability by 21%. The researchers say that this new material can also be used for in-organic LEDs (including microLEDs).

Researchers from LORDIN, in collaboratioon with researchers from Korea's Dankook University, Gachon University and Hongik University, have reported on a highly efficient and stable ultra-pure blue phosphorescent OLED emitter, based on Lordin's Tetradentate Pt(II) material Complex with a vibration suppression effect.

The researchers say that the new emitter offers a lifetime of 451 hours (LT50 at 1,000 cd/m²), and an EQE of 25.1%. The emission spectrum is extremely narrow - full width at half a maximum of 22 nm. The researchers further developed a tandem OLED device based on this new emitter, which achieves an EQE of 50.3% and a lifetime of 589 hours (LT 70).

Researchers from the Fraunhofer IPMS, together with colleagues from the Max Planck Institute for Multidisciplinary Natural Sciences (MPI-NAT) are developing OLED-based optical stimulators for future cochlear implants.

The researchers explain that optogenetics is a method that uses light to control genetically modified cells in living tissues. By introducing light-sensitive proteins into cells, their activity can be precisely turned on and off with light pulses. This technique is commonly used in neuroscience to study the functions of nerve cells and to activate or inhibit specific neuronal populations.

Researchers from the University of Michigan, in collaboration with OLEDWorks, has developed an OLED device that converts near infrared (NIR) light into visible light and amplifies it more than 100 times. Compared to current night-vision systems based on image intensifiers, this device could enable a much more efficient and light-weight solution. 

The OLED device integrates a photo-absorbing layer inside the OLED stack, that converts infrared light into electrons. Those electrons are converted into visible light photons via the OLED layers - about five photons are created for each electron, and some of these photons are re-absorbved, converted into more electrons, and then even more photons, creating a great amplification of the absorbed NIR light. 

Researchers from Shenzhen University and Wuhan University have designed new white OLED devices that exhibit exceptional power efficiency (over 190 lm/W, 39% EQE) and extended operational lifetime (LT80 446 hours at 1,000 cd/m²). 

The new device uses a blue TADF emitter emitter combined with a yellow MR-TADF emitter. The light is a warm white light. The researchers also used the same technique to create a standard white emission device, that still achieves a high EQE of 35.6%, thus further validating the strategy.

Researchers from Kyung Hee University in Korea have designed highly efficient stretchable OLED devices by incorporating the prestretched elastomer with optical adhesive film.

The researchers say that the so-called Geometrical Stretchable OLED (GSOLED) device enhances the efficiency of the OLEDs with the light extraction phenomenon brought by nanowavy corrugated structures. Furthermore, GSOLED shows stability in stretchable conditions and displays narrower emission spectrum with improved color purity.