Technical / Research - Page 11

Eindhoven's Technical University (TU/e) announced a new project called SEQUOIA that aims to develop a strategy for the suppression of exciton quenching in OLED devices.

Exciton quenching, caused due to unwanted interactions among excitons and between excitons and charges, causes the efficiency of OLEDs to drop as brightness increases. The researchers hope to develop new materials and new OLED design to suppress (or hopefully eliminate entirely) this problem.

At the end of this month Toray Research Center (TRC) will host an online webinar focused on OLED technologies. TRC, who supplies technical analysis and support for R&D and manufacturing, invites you to attend the online lectures at no cost, to learn more about OLED technologies and analysis of OLED devices.

The webinars will include recorded presentations, which will be available online from February 22 to March 08. You can register for the webinars here.

Researchers from National Taiwan University, led by Prof. Chung-Chih Wu, have developed a 3D pixel configuration for OLED devices, which can improve the light extraction. The new design can improve the external quantum efficiency of a top-emitting OLED device by up to 30%.

The new design uses a 3D reflective pixel structure filled with a patterned high-index material. The researchers created several pixels with difference sizes, and found that the smaller the pixel, the higher the efficiency boost.

Researchers from Korea's KAIST and ETRI institute developed a new metal oxide charge transfer complex that, when dispersed in the OLED stack, can improve the OLED efficiency.

The researchers have applied this material to a green and blue OLED device. The current efficiency of the green OLED was enhanced by 189%, while the external quantum efficiency of the blue OLED was improved by 17%.

Researchers from japan's National Institute for Molecular Science and the University of Toyama have developed a new OLED structure that can operate at low voltages - the entire OLED runs at 1.5 Volt (compared to 4.5V commonly used in current OLED devices). The researchers say that this is the lowest operation voltage reported for an OLED devices with a luminance of 100 cd/m². In fact the researchers have demonstrated the OLED at 177 cd/m².

The researchers say that the OLED has a smaller turn-on voltage at 0.97 V than the optical energy of emitted photons at 2.04 eV (608 nm), because the OLED is based on upconversion (UC) transition associated with triplettriplet annihilation that doubles the energy of excited states.

Researchers from the University of Minnesota Twin Cities managed to deposit flexible OLED devices using 3D printing. The whole OLED stack (including the electrodes, interconnects, insulation, and encapsulation) was printed using a table-top 3D printer (custom build, and reportedly costing like a Tesla Model S).

The researchers used the new method to create a low-cost flexible OLED display of sort, made from relatively large pixels (see video above). The whole panel is 1.5 x 1.5 inch in size, with 64 pixels. The team is now working to improve the density of the process.

LG Display unveiled its latest OLED TV technology, branded as OLED EX. LG says that these WOLED panels combine new deuterium compounds and personalized algorithms to improve the image quality and increase brightness by up to 30%. EX is an acronym of Evolution and eXperience.

LG Display says that it has "successfully converted the hydrogen elements present in organic light emitting elements into stable deuterium". LGD extracts the deuterium compounds from water, and after stabilization, the compounds allow the OLED devices to be brighter - and also last longer.

OLEDON says that it has developed a new curved plane-source evaporation shadow mask process that can be used for OLED microdisplay fabrication, with a potential density of 10,000 PPI (minimum shadow distance of 0.18um). Using this technology it will be possible to create direct-emission microdisplays.

In the video above, you can see the lecture OLEDON's CEO gave last month at iMID 2021, that explains the new technology.

In 2020, US-based Kebotix was awarded with a US DoE grant to develop AI-based molecular screening technology to identify novel blue OLED emitters. The company now announced that it has managed to discover several new classes of candidate materials, and develop device prototypes.

Kebotix says it aims to start testing these molecules with device makers in early- to mid-2022.

Korea-based OLUM Material announced that it is starting to develop fine metal masks (FMM) for 8.5-Gen (2200x2500 mm) OLED production. Current FMM technologies are limited to 6-Gen substrates (1500x1850 mm).

As demand for larger mobile OLED displays, for laptops, tablets and monitors is on the rise, OLED makers aim to start making these panels on larger substrates. Samsung Display is considering, according to reports, a 8.5-Gen AMOLED fab dedicated for laptop and IT displays.