Power consumption

In 2014 Konica Minolta started constructing its groundbreaking R2R flexible OLED lighting fab. The project saw many delays and entered production later than planned, and KM started producing panels at low volume at around 2020. The company recently started to ramp up production, and today we hear of one of its first customers and partners, Sentry Enterprises.

Sentry, a fintech company, launched the Radiance card illumination platform, which enables credit card (and other payment card) issuers to offer a unique experience by using an OLED lighting panel embedded in the card. The OLED panel is produced by Konica Minolta. The card works without a battery, and the OLED panel is powered by the NFC receiver upon a transaction (a technology that was demonstrated by KM back in 2020).

Researchers from the University of St. Andrews in the UK, led by Professor Ifor Samuel and Professor Eli Zysman-Colman, identified the key processes controlling the efficiency of TADF OLED emitters under high brightness. This could assist material develops on their quest to design materials that maintain high efficiency at high brightness.

The researchers explain that OLEDs have lower efficiency at higher brightness, and in many TADF materials, the efficiency roll-off is severe, so that the high efficiencies achieved at very low brightness are not maintained at higher brightnesses needed for displays or lighting applications. For the first time, the researcher identified the key processes controlling the triplet population, and propose a figure of merit for efficiency roll-off.  

Researchers from the UK's Northumbria, Cambridge, Imperial and Loughborough universities developed a new Hyperfluorescence OLED emitter system based on a new molecular design, which is highly efficient and simple to produce.

The researchers explain, that in Hyperfluorescence  systems, the elimination of the Dexter transfer to terminal emitter triplet states is the key towards OLED efficiency and stability. Current devices rely on high-gap matrices to prevent Dexter transfer, which unfortunately leads to overly complex devices from a fabrication standpoint. The researchers developed a novel molecular design in which ultranarrowband blue emitters are covalently encapsulated by insulating alkylene straps. 

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 Durham University, led by Professor Andrew Monkman, discover new OLED emitters that offer high performance in a hyperfluorescence emission system. The main new material, a molecule called ACRSA, was found to triple the efficiency of hyperfluorescence OLED devices.

These OLED emitters aren't actually new - they were studied years ago, but were found to be poor emitters. That was true when used as OLED emitters, but when used in a hyperfluorescence system (which combines both fluorescent and TADF emitters), these were surprisingly efficient. The ACRSA emits a green emission, but deep blue light emission can be achieved by transferring ACRSA's energy to a blue terminal emitter. This approach reduces exciton energy compared to direct blue emission in devices, allowing more stable, longer-lasting blue OLEDs.

Researchers at Lawrence Berkeley National Laboratory (Berkeley Lab), led by Prof. Peidong Yang, developed a new 3D printing ink based on perovskite materials, that exhibits unity photoluminescence quantum yield (PLQY). Interestingly, as it is a 3D printable ink, it is possible to create luminescent objects from it, as seen in the image below:

The researchers brand the new ink as 'supramolecular ink', and say it is produced without any rare metals. It is a combination of several powders containing hafnium (Hf) and zirconium (Zr), and is made at room temperatures. In a process called supramolecular assembly, tiny molecular building block structures are self-assembled within the ink. These supramolecular structures enable the material to achieve stable and high-purity synthesis at low temperatures.

In 2023, we reported on research conducted at Germany's Max Planck Institute, led by Prof. Paul W.M. Blom, that looks into single-layer OLED devices. In such devices, a single TADF OLED emitter layer is sandwiched between two electrode - a much simpler design compared to commercial OLED devices that use multilayer stacks, sometimes with 10 or more layers. The researchers the the MPI say that in fact it is possible to develop highly efficient OLEDs with just the TADF emitter - and have demonstrated 100% IQE single-layer devices, with an EQE of 27.7%. 

Prof. Blom's group continues to improve its single-layer TADF OLED device, and have now reported that by employing a recently developed trap-free large band gap material as a host for the DMAC-BP OLED emitter, a nearly balanced charge transport is achieved. The device achieves a record power efficiency for DMAC-BP TADF OLEDs of 82 lm/W - surpassing  the best reported multilayer power efficiencies of 52.9–59 lm/W. This is due to the lower operating voltage. The single-layer device reaches an external quantum efficiency (EQE) of 19.6%, which is only slightly lower than the reported EQEs of 18.9–21% for multilayer devices. In addition to the high power efficiency, the operational stability is greatly improved compared to multilayer devices and the use of conventional host materials in combination with DMAC-BP as an emitter.

LG Display announced that it has developed its 2nd generation Multi-Lens Array (MLA) technology, branded as META Technology 2.0.  The company demonstrated a 83" META 2.0 OLED TV panel, during CES 2023. The company will apply this technology to several of its 2024 OLED TVs, ranging in size from 55-inch to 88". 

META 2.0 WOLED panels achieve a peak brightness of 3,000 nits - a 42% improvement over the company's conventional panels. LGD explains that META 2.0 includes a pattern of optimized micrometer-scale lenses with an optimized lens angle, an upgraded "brightness enhancing algorithm" called META Multi Booster, and a full-range brightness detail enhancing algorithm called Detail Enhancer. All of these new technologies, combined, makes for a META 2.0 panel. In a 77-inch 4K panel, there are 42.4 billion micro lenses (!).

US-based Pixelligent is an advanced materials company that delivers next generation optical materials applications in lighting and displays. For the OLED industry, Pixelligent offers materials that significantly increase light output by increasing the refractive index of materials in the device.

Pixelligent's President and CEO, Craig Bandes, was kind enough to answe a few questions we had, to learn more about Pixelligent and its solutions for the OLED industry.

Hello Craig! Can you explain your technology and materials and how they enhance the efficiency of OLED display?

We are best known for our high refractive index (HRI) nanocrystal formulations and dispersions that deliver breakthrough performance in next-generation electronics, like extended reality, displays, optics, and sensors. We designed our PixJet®, PixNIL®, and PixClear® products to offer the best combination of brightness, clarity, operating efficiencies, and device-lifetime. 

In 2021, LG Display started to adopt deuterated OLED compounds in its WOLED panels, to improve the lifetime, efficiency and brightness. Today, all of LG's WOLED TV panels use deuterated blue OLED emitters, in which hydrogen is replaced by its more stable isotope, deuterium. The higher stability enables longer lifetime, which in turn enables higher brightness and efficiency.

It is now reported in Korea that LG Display now aims to expand the adoption of deuterated OLED compounds to its red and green and yellow emitters, and also other layers in the OLED stack. If this report is true, it means that LGD will also use the technology in its mobile (p-OLED) panels, not just its OLED TV ones.