Displays

Perovskite-Info is proud to announce an update to our Perovskite for the Display Industry Market Report. This market report, brought to you by the world's leading perovskite and OLED industry experts, is a comprehensive guide to next-generation perovskite-based solutions for the display industry that enable efficient, low cost and high-quality display devices. The report is now updated to July 2024, with all the latest commercial and research activity - including 9 new research papers, new company, new brochures, and commercial updates and more!

Reading this report, you'll learn all about:

• Perovskite materials and their properties
• Perovskite applications in the display industry
• Perovskite QDs for color conversion
• Prominent perovskite display related research activities

The report also provides a list of perovskite display companies, datasheets and brochures of pQD film solutions, an introduction to perovskite materials and processes, an introduction to emerging display technologies and more.

Researchers from Zhejiang University, LinkZill Technology, Jilin University, and Linköping University have found that the electroluminescence rise time of perovskite LEDs (PeLEDs) can be reduced to microseconds using an individual-particle passivation strategy. This addresses a known issue with PeLEDs, that tend to have electroluminescence rise times over milliseconds due to ion migration in crystal structure, which is problematic for the development of high-refresh-rate displays.

The team demonstrated a second-generation digital display screen that uses perovskite light-emitting diodes instead of standard LED technology. In their study, the group made improvements to the device and demonstrated its sensing capability.

A few months ago, Helio Display Materials, a developer of perovskite-based color conversion materials for displays, announced that it entered into a strategic partnership with Haylo Ventures, a venture operator specializing in accelerating the commercialization of deep tech. 

This collaboration targets micro displays for AR/VR headsets, signifying a pivotal shift in Helio's strategic direction.

Researchers at China's Shanghai University, Jilin University, University of Science and Technology of China, Chinese Academy of Sciences, Korea's Pohang University of Science and Technology (POSTECH) and UK's University of Cambridge have reported efficient and color-stable perovskite LEDs (PeLEDs) across the entire pure-red region, with a peak external quantum efficiency reaching 28.7% at 638 nm, enabled by incorporating a double-end anchored ligand molecule into pure-iodine perovskites.

Light-emitting diodes (LEDs) based on metal halide perovskites (PeLEDs) with high color quality and facile solution processing are promising candidates for full-color and high-definition displays. However, the team explained that despite the great success achieved in green PeLEDs with lead bromide perovskites, it is still challenging to realize pure-red (620–650 nm) LEDs using iodine-based counterparts, as they are constrained by the low intrinsic bandgap.

Researchers at China's Shanghai University, Southern University of Science and Technology, The University of Hong Kong, Yunnan University, Beijing Institute of Technology and Japan's Yamagata University have developed a stable, efficient and high-color purity hybrid light-emitting diodes (LEDs) with a tandem structure, by combining perovskite LED and commercial organic LED technologies. 

Device structure. Image credit: Light: Science & Applications

Perovskite-based LED technology can have tunable emission wavelength in visible light range as well as narrow linewidth, which makes it a promising contender among current light-emitting display technologies. However, it still suffers from severe instability driven by electric field. The research team in this work set out to tackle this challenge, by developing a method to create efficient and stable hybrid perovskite-organic light-emitting diodes.

Researchers at City University of Hong Kong (CityU) have presented a novel material design strategy and simple device-manufacturing process for skin-conformable perovskite-based alternating-current electroluminescent (PeACEL) devices. 

Working mechanism of the PeACEL device. Image credit: Nature Photonics

These devices exhibit a narrow emission bandwidth (full-width at half-maximum, <37 nm), continuously tunable emission wavelength (468–694 nm), high stretchability (400%) and adequate luminance (>200 cd m−2). 

Micro-LED (also known as mLED or µLED) is a display technology based on miniature LED devices that are used to directly create color pixels. Micro-LED displays are highly promising and have the potential to create efficient and great looking flexible displays, which could challenge even the most impressive high-end OLED displays. Micro LEDs are attracting significant attention as next-generation displays owing to their desirable characteristics such as low power consumption, high contrast ratio, high brightness, fast response speed, and long life span.

Perovskite materials can benefit the MicroLED industry in two ways: as materials for color conversion (using perovskite-based QDs) and in perovskite-based LED emitters. Much R&D work is taking place on both these fronts, and interest seems to be growing.

Researchers at Linköping University, Nanjing University and NanjingTech have developed a multifunctional display that uses photo-responsive metal halide perovskite LEDs as pixels. The perovskite LED display can be simultaneously used as a touch screen, ambient light sensor and image sensor (including for fingerprint drawing) without integrating any additional sensors. The light-to-electricity conversion efficiency of the pixels also allow the display to act as a photovoltaic device that can charge the equipment.

Illustration of functions realized by the multifunctional display. Image from Nature Electronics

This is a step forward compared to current display screens, which are typically only used for information display, but can have a range of different sensors integrated into them for functions such as touch control, ambient light sensing and fingerprint sensing. According to the team, photo-responsive light-emitting diodes (LEDs), which can display information and respond to light excitation, could be used to develop future ultra-thin and large screen-to-body ratio screens. However, photo-response is difficult to achieve with conventional display technologies. 

Researchers from China's Xiamen University, Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Yang Ming Chiao Tung University and Hon Hai Research Institute have reported a self-polarizing RGB device utilizing semipolar micro-LEDs and perovskite-in-polymer films aimed at improving backlight applications.

Structure of an LCD based on semipolar blue μLEDs excite anisotropic perovskite NCs as backlight. Image from Opto-Electronic Advances

In backlighting systems for LCDs, conventional red, green, and blue (RGB) light sources that lack polarization properties can result in a significant optical loss of up to 50% when passing through a polarizer. To address this inefficiency and optimize energy utilization, the scientists developed a high-performance device designed for RGB polarized emissions. The device uses an array of semipolar blue µLEDs with inherent polarization capabilities, coupled with mechanically stretched films of green-emitting CsPbBr₃ nanorods and red-emitting CsPbI₃-Cs₄PbI₆ hybrid nanocrystals. 

Perovskite nanocrystals (PNCs) have considerable potential as next-generation display materials thanks to their excellent photoluminescence quantum yield (PLQY), wide color gamut, and narrow emission bandwidth. However, due to their weak stability against solvents, their patterning remains a challenge. In a recent study, researchers at Ajou University, Hanyang University, Sungkyunkwan University, Macquarie University and Kongju National University developed functional organic ligands (AzL1-Th and AzL2-Th) for the fine pixelation of perovskite nanocrystal (PNC) displays. 

Functional ligands containing photocurable azide moieties exhibit good charge transport properties and fast and efficient photocrosslinking performance, while maintaining a high PLQY. The team successfully demonstrated the crosslinked PNC light emitting diodes using AzL1-Th. The results suggest the high potential of photocurable ligands for the micro-patterning of PNC films without film damages.