Session Index

A high efficiency deep-blue thermally activated delayed fluorescence (TADF) organic light emitting diode (OLED) was demonstrated by incorporating a multiple-resonance-induced thermally activated delayed fluorescence (MR-TADF) emitter and a novel host material with carbazole moiety. The device showed its max current efficiency (CEmax) of 12.0 cd/A, maximum power efficiency (PEmax) of 12.6 lm/W, maximum external quantum efficiency (EQEmax) of 21.3%, Commission Internationale de l'Eclairage (CIE) coordinates of (0.126, 0.108) and peak emission wavelength at 466 nm. Notably, OLED based on MR-TADF emitter exhibited narrow electroluminescence spectrum with full width at half maximum of 22 nm.

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Achieving low ambient light reflection is essential for OLED displays. However, inevitable surface undulation associated with pixel structures naturally induces scattering reflection over larger viewing angles, even with circular polarizers. This work reports optimized designs of OLED pixel structures for minimizing such scattering reflection and for achieving consistently low ambient light reflection over angles and enhanced viewing experiences.

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In this study, the patterning work is performed through the photo-conductor properties of the coated PVK film and the dynamic scattering of the liquid crystal material. The scattering regions of the pattern can maintain a stable state for a long time, and the scattering state can be transformed into a transparent state by high frequency AC voltage.

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In this work, passivation layers of Al2O3 and SiO2 are simultaneously deposited on the side wall of the μ-LED to improve the output power, external quantum efficiency and minimum leakage current. Compared with the leakage current of the μ-LED without passivation layers, the maximum EQE can be improved by 32%.


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We designed four host materials in spiro[fluorene-9,9'-phenanthrene-10'-one] core configurations, decorated with substituents such as cyano, triarylamine, and carbazole groups. These compounds have an adequate energy bandgap suitable as host materials for yellow emitters. These materials are combined with CN-T2T to construct a mixed host in the devices. As a result, the H4/CN-T2T-based OLED with PO-01 yellow emitter has the best performance, achieving a peak efficiency of 27.1% (80.0 cd/A, 11.3 lm/W), a low turn-on voltage of 2.1 V, and high maximum luminance of 142464 cd/m2. This performance is one of the highest values reported in the literature for PO-01-based devices.

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An efficient green thermal activated delayed fluorescence (TADF) organic light emitting diode was demonstrated by incorporating an acridine (Ac)-derivative host material and a green reported acridine dopant, DMAC-TRZ. The Ac moiety possess the electron donating capability and expect to improve of hole transport in OLED application. Consequently, the TADF-OLED in the absence of the electron blocking layer can exhibit low turn on voltage of 2.9 V, maximum current efficiency of 43.9 cd/A, maximum power efficiency of 42.0 lm/W and maximum external quantum efficiency of 12.1%.

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Herein, we report the design and synthesis of three donor-acceptor-acceptor-configured host materials composed of a thioxanthone or diphenyl sulfonyl acceptor and phenyl carbazolyl donor. These systems exhibit strong deep-blue photoluminescence (422–432 nm) in solutions and red-shifted emission (472–486 nm) in thin films. These compounds were used as hosts for red-emitting Ir(piq)2acac in OLEDs. The phosphorescent OLEDs based on TP-1, TP-2, and TP-7 achieve excellent peak external quantum efficiencies (luminance efficiencies) of 22.9% (14.0 cd/A), 21.6% (12.0 cd/A), and 21.9 (12.3 cd/A), respectively. These results highlight the promising prospects of these host materials in practical OLED applications.

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Three bipolar host materials were proposed, consisting of 2-phenylbenzo[d]thiazole acceptor and different donor moieties. These materials are designed to endow themselves with balanced carrier transport capabilities and sufficient band gaps for green phosphors. As a result, the Ir(ppy)3-based device with BTZ-CZ host exhibited excellent performance, such as high peak efficiency of 26.3%, a low turn-on voltage of 2.6 V, and high maximum luminance of 192557 cd/m2. Furthermore, the balanced carrier transport capability of BTZ-CZ can help expand the recombination region and thereby reduce triplet-triplet annihilation. These results implied that these molecular designs have a high potential for realizing efficient OLEDs.

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In this work, we demonstrate a novel process of green laser crystallization (GLC) for poly-Si crystallization. Under specific crystallization power the electrical characteristics could be optimized, exhibiting higher mobility of 28.218 cm2/V-s, lower threshold voltage (VTH) of -0.202V, higher on/off current ratio (ION/IOFF) of 2.32×107, subthreshold swing (S.S.) of 93.71 mV/dec and low off-state current in comparison with other crystallization powers.

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Electrically switchable handedness of circular polarized light (CPL) using broadband quarter waveplate (BBQWP) with twisted nematic liquid crystals (TNLCs) is reported. The BBQWP consists of two LC plates. Using a TNLC plate, handedness of CPLs can be switched by turning on/off a suitable voltage applied onto the TNLCs.

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ITO/Ag/ITO (40 nm/20 nm/40 nm) as transparent display electrodes can improve the overall performance of μ-LED displays.In terms of optical measurements, the optical output power was 1.38 mW under 3 mA current injection.The external quantum efficiency reaches the highest point of 20.2% at 0.1mA.The display brightness is 529 nits under 3V.

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We report on a high-performance polariton vertical light-emitting transistor (VLET)
by integrating a ZnO transistor and a Super Yellow inverted OLED in a microcavity. The
VLET exhibits the maximum EQE of 2.4% and spatially uniform emission from the ZnO
pattern, while having a narrow-band, weakly angle-dependent spectrum that follows lower
polariton mode. Furthermore, we demonstrate the VLET operation in the ultrastrong coupling
regime with a Rabi splitting energy of 0.7 eV (25% of the exciton absorption energy). This
high emission efficiency and unique spectral properties make this VLET a promising building
block for novel display applications.

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We carried out a comparative study to evaluate the feasibility of Ag@Au and Au@Ag core-shell nanoparticles (NPs) to enhance the emitter emission in visible light. As a result, Ag@Au NP with fixed diameter of 50 nm can increase the red emitter quantum yield when the core diameter is smaller than 30 nm. In contrast, Au@Ag NP is suitable for improving the emitter quantum yield in the whole visible region and shows greater radiative enhancement.

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We have developed a new deep blue fluorescent host material based on benzene derivative for high efficiency organic light-emitting diode (OLED). By optimizing the dopant concentration of emitter in the emitting layer (EML) from 3% to 10%, the maximum external quantum efficiency (EQEmax) of deep-blue OLED can achieve as high as 5.5% and showed a deep blue emission with peaks at 432 nm and CIE coordinates of (0.1524,0.0548).



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