OLED Lifetime

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 Tsinghua University in Shenzhen, China, have managed to dramatically increase the stability of OLED devices by the adoption of deuterated host material.

The researchers, led by Prof. Man-Chung Tang, have designed and synthesized deuterated anthracene-based hydrocarbon PNA as the new host material. The researchers have observed that the faraday loss decreases with the increase of the deuteration degree.

A report from Korea says that LG Display has successfully developed an OLED panel that is based on a blue phosphorescence emitter. The blue PHOLED, provided by Universal Display, offers 100% IQE, up from 25% used by current fluorescence emitters. This will result in around 20-30% power saving for the display itself (depending on the images shown).

UDC has been developing blue emitters for many years, and recently the company said that the development will take a few more months and won't be ready in 2024. The main challenge is increasing the lifetime of the materials. However LG Display has adopted a tandem design to enable a commercially ready display, perhaps even sooner than UDC planned.

OLED displays have been gaining popularity rapidly, and are already the dominant smartphone display technology. OLEDs are also the display technology of choice in the smartwatch market, making inroads into the TV, monitor, laptop and tablet markets. The future of the OLED industry looks bright.

In recent years, the focus of the industry, beyond increasing capacity and reducing production costs, has been improving the performance of OLEDs in the areas of display brightness, efficiency, and lifetime. Brightness is required in many applications - from TVs (for HDR and to view in ambient lighting) through smartphones (outdoor viewing) to automotive, and efficiency is a plus in any scenario (but mostly in mobile displays). Display lifetime is already good enough for many applications, but in some cases (like automotive, and IT displays) it is critical. These three properties usually go together - if you can make more efficient OLED displays, you can drive them at a lower current to achieve the same brightness, and so lifetime increases, or you can achieve higher brightness, etc. 

LG Display says that it has started to mass produce tandem OLED laptop panels, the first company to do so. LGD says its tandem architecture double the lifetime of its OLEDs, reduce power consumption by up to 40%, and enable up to three times the brightness.

LGD has been producing tandem OLED displays since 2019, mainly for the automotive industry. This expertise has enabled it to be Apple's main tandem OLED display suppler for its 2024 iPad Pro devices, and now to be the first one to produce tandem laptop panels. 

Researchers from the University of Manchester, University of Cambridge and University of Eastern Finland, led by Dr. Alexander Romanov have developed a new deep-blue Carbene-Metal-Amide (CMA) OLED emitter material with promising operating lifetime.

The emitter is based on a a new CMA complex with a rigid amide donor, benzoguanidine. The researcher say that the new design unlocks bright charge-transfer deep-blue emission with 100% photoluminescence quantum yields. The excited state lifetimes of the new CMA complexes are among the lowest reported to date among all TADF emitters
(down to 213 ns), resulting in remarkably fast radiative rates of up to 4.7 × 10 6 s⁻¹ . 

According to reports, BOE has commercialized a new tandem OLED architecture, that enabled an improvement of 40% in power consumption and a 600% increase in display lifetime. 

As you can see from the teaser poster above, Chinese smartphone maker Honor will release the first phone to adopt the new panel, the Honor Magic 6 Ultimate, next week on March 18th.

Researchers from the UK's National Physical Laboratory (NPL), together with the Samsung Advanced Institute of Technology (SAIT), released a new study to better understand the degradation of blue OLED devices. 

Close-up of the OrbiSIMS instrument’s vacuum chamber showing the nozzles of the ion beams and electrode that extract ionised molecules for analysis (Picture credit: NPL)

The OLED degradation mechanisms that limit the lifetime of blue OLED emitters, whether physical, chemical or something else, are still not yet fully understood. Understanding the degradation mechanism of blue OLEDs is essential to improve their performance and stability. The NPL / SAIT team used OrbiSIMS, an innovative mass spectrometry imaging technique invented at NPL in 2017, to study OLED degradation.