- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 International Energy and Sustainability Conference (IESC) - Farmingdale, NY, USA (2019.10.17-2019.10.18)] 2019 International Energy and Sustainability Conference (IESC) - Methodology for the implementation of photovoltaic energy in a microgrid
摘要： A new accurate voltage-programmed pixel circuit for active-matrix organic light-emitting diode (AMOLED) displays is presented. Composed of three TFTs and one storage capacitor, the proposed pixel circuit is implemented both in a-Si and a-IGZO TFT technologies for the same pixel size for fair comparison. The simulation result for the a-Si-based design shows that, during a programming time of 90 s, the pixel circuit was able to compensate for a 3 V threshold voltage ( ) shift of the drive TFT with almost no error. In contrast, the a-IGZO-based pixel circuit, has a larger current error (of around 8%), despite its proven three-fold higher speed.
关键词： Active-matrix organic light-emitting diode (AMOLED),compensation,oxide thin-film transistor (TFT),amorphous silicon (a-Si)
更新于2025-09-19 17:13:59
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Recent advances in thermally activated delayed fluorescence for white OLEDs applications
摘要： Thermally activated delayed fluorescence (TADF) materials, which can harvest all excitons without utilizing any noble metals to emit light, are becoming the key cornerstone for developing the next generation of organic light-emitting diode (OLED) devices. In recent years, TADF materials are attracting numerous attentions as a new surge of research focuses on both science and industry owing to their high efficiency, low power consumption, and low production cost attributes when applied to white OLEDs. The design and application of TADF in WOLED devices have also experienced the rapid development in fundamental science and industrial technology perspectives. In the present review, the specific reverse intersystem crossing mechanism and evolution of TADF is outlined firstly, and then the latest research progress of TADF-WOLEDs is summarized and discussed. TADF/conventional fluorescence, TADF/phosphorescence, all TADF and TADF exciplex-based WOLEDs are categorized and elaborated in terms of the device structure, working mechanism, efficiency, color-rendering index, etc. Finally, we conclude with the future challenges and opportunities in high-quality TADF devices and application area.
关键词： Thermally activated delayed fluorescence,exciplex,OLED,TADF,RISC,white OLEDs,organic light-emitting diode,reverse intersystem crossing
更新于2025-09-19 17:13:59
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Electro-optically efficient and thermally stable multilayer semitransparent pristine Ag cathode structure for top emission organic light emitting diodes
摘要： To attain high efficiency and stability in a top-emission organic light-emitting diode (TEOLED), the semitransparent metal cathode must have high transmittance, low absorbance, and uniform surface properties under continuous driving conditions. However, conventional semitransparent metal electrodes have numerous fundamental issues. Here, we report an electro-optically efficient and stable semitransparent pristine thin Ag cathode configuration for the high performances of TEOLED. A multilayer semitransparent cathode structure is fabricated by sandwiching a thin silver (Ag) layer between new organic wetting inducer and capping layer, 1,4-bis(2-phenyl-1,10-phenanthrolin-4-yl)benzene (p-bPPhenB). A thin Ag layer in the presence of p-bPPhenB exhibits superior optical and electrical properties including a high transmittance of 83.8% at 550 nm, low absorbance of 7.65% at 550 nm, and the low sheet resistance of 2.1 Ω/□, respectively, at room temperature and even under 110 OC for 100 hours. It is observed that our organic wetting inducer and capping layer, p-bPPhenB has considerable influence on the stabilization of surface properties of the thin Ag film by forming coordination bond between the Ag atoms and nitrogen atoms of p-bPPhenB through donating unshared electrons to the Ag atom. An optically optimized phosphorescent green TEOLED with this pure Ag cathode configuration enables a low driving voltage of 5.0 V at 10 mA/cm2 and remarkably high maximum current efficiency of about 167 cd/A compared with the Mg:Ag (10:1) cathode (5.4 V and 109 cd/A).
关键词： micro-cavity effect,organic wetting inducer,semitransparent pristine silver cathode,top-emitting organic light emitting diode,thermal stability
更新于2025-09-16 10:30:52
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Starburst-type triarylphosphine oxide trimers forming a stable amorphous n-type layer in solution-processed multilayer OLED
摘要： Novel starburst-type triphenylphosphine oxide trimers PO-1 and PO-2 were synthesized aimed at application as an electron-transporting material for multilayer organic light-emitting diodes (OLEDs). They showed high glass transition temperatures (Tg; 175 and 205 (cid:1)C, respectively) and high lowest triplet energies (T1; 2.81 and 2.78 eV, respectively). Their high solubility in 2-propanol allowed us to fabricate multilayer OLEDs by solution processing, and a double-emitting layer OLED consisting of poly(9-vinylcarbazole)-based p-type and PO-1-based n-type layers doped with a phosphorescent material (FIrpic) showed efficient sky-blue electroluminescence with a maximum external quantum efficiency of 9.33%.
关键词： Solution processing,Organic light-emitting diode,Phosphine oxide,Double emitting layer,Multilayer,Electron-transporting material
更新于2025-09-16 10:30:52
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High efficiency color-temperature tunable organic light-emitting diode
摘要： In this study, we demonstrate a high-efficiency and high light-quality organic light-emitting diode (OLED) with color temperature tunable from the 1700 K of dusk-hue, 1900 K of candles and 2500 K of incandescent bulbs to 3000 K of warm-white light. The color-temperature tunable OLED device was achieved by utilizing a hybrid system and inserting a carrier modulation layer (CML) between the emission layers. In addition, the electron-rich charge transport properties of EML-1, facilitated via a 3 : 1 composition ratio of the 3P-T2T host to TPD-15 co-host, played a crucial role in tuning the desirable low-color temperature of the fabricated OLED devices. The current efficiency, power efficacy, and spectrum resemblance index (SRI) of the studied OLED are 40.2 cd/A, 40.3 lm W?1 and 82.2 at 1000 cd m?2, respectively. The resultant devices show great potential to advance the study and development of physiologically friendly lighting and enable a successful commercial OLED lighting product in the market.
关键词： organic light-emitting diode,physiologically friendly lighting,high light-quality,color temperature tunable,high efficiency
更新于2025-09-16 10:30:52
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A review of highly reliable flexible encapsulation technologies towards rollable and foldable OLEDs
摘要： As the demand for flexible, rollable, and foldable displays grows, various state-of-the-art component technologies, including thin-film transistors (TFTs), electrodes, thin-film encapsulations (TFEs), and touch screen panels, have been developed based on organic light-emitting diodes (OLEDs) with flexible organic layers. Developing highly reliable flexible OLEDs is essential to realize flexible displays, but the flexible encapsulation technology still has technical difficulties and issues to be addressed. This review covers the recent developments in encapsulation technologies, particularly their material and structural designs, for highly reliable, flexible OLEDs. The solution concepts for the existing technical hurdles in flexible encapsulations are addressed. Among the various advanced flexible encapsulation technologies developed so far, neutral-axis engineering with a thin metal layer and a crack arrester is introduced.
关键词： organic light-emitting diode (OLED),Thin-film encapsulation (TFE),foldable,flexible,rollable
更新于2025-09-16 10:30:52
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Chemically doped hole transporting materials with low cross-linking temperature and high mobility for solution-processed green/red PHOLEDs
摘要： Recently, developing insoluble cross-linkable functional layers plays a vital role for solution-processed organic light emitting diodes (OLEDs). Here, two vinyl-based cross-linkable hole transporting materials V-TPAVTPD and V-TPAVCBP are designed and synthesized. Additionally, cationic photoinitiator 4-octyloxydiphenyliodonium hexafluoroantimonate (OPPI) is first introduced to chemically induce vinyl-based photo cross-linking process, aiming at lowering cross-linking temperature and enhancing hole mobility. As a result, cross-linking can occur at expressly low temperature of 120 °C with >95% solvent resistance. Moreover, hole mobility is markedly enhanced with the value higher than 10-3 cm2 V-1 s-1. When applying hole transporting layers (HTLs) to solution-processed green and red phosphorescent OLEDs, devices exhibit excellent properties. Particularly, the maximum current efficiency of 54.0 cd A?1 (green), 9.8 cd A?1 (red) and external quantum efficiency of 15.5% (green), 15.0% (red) are obtained when OPPI doped V-TPAVCBP serves as HTL. This low temperature feasible cross-linking process to prepare HTLs with preferable hole mobility promotes the development of OLEDs.
关键词： organic light emitting diode,low temperature,solution-processed,cross-linkable,4-octyloxydiphenyliodonium hexafluoroantimonate,hole transporting material
更新于2025-09-16 10:30:52
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Electrical Conduction and Luminescence for Inverted-Type Organic Light-Emitting Diodes with Polyethyleneimine
摘要： Organic light-emitting diodes (OLEDs) have showed the unique potentials of display by bendable, foldable and storable panels. In general, since OLEDs consisted of multi organic layers, their electrical conduction would be complicated. Aluminum quinoline (Alq3) was a classical and famous fluorescent material. We studied the conduction properties of inverted Alq3-bilayer OLEDs. Since the barrier height of electron injection from ITO cathode to Alq3 was higher than that from LiF/Al, electrons were little injected into Alq3 and the current density in the absence of EL was controlled by holes. In the specimen using polyethyleneimine as an injection layer, the current density and hole injection were influenced by electron injection for the current continuity. Despite that holes could arrive at the counter cathode through Alq3, the recombination zone was located near a hole transport layer as the conventional bilayer OLED. It was suggested that the carrier transport in an organic layer depends on both carrier injections.
关键词： Polyethyleneimine,Organic light-emitting diode,Inverted structure,Carrier injection
更新于2025-09-16 10:30:52
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A Pixel Circuit With Wide Data Voltage Range for OLEDoS Microdisplays With High Uniformity
摘要： A new pixel circuit is proposed for the realization of high resolution and high uniformity organic light-emitting diode on silicon (OLEDoS) microdisplays in this article. A compensation scheme is adopted to mitigate the influence of threshold voltage variation of the driving transistor on display uniformity. Furthermore, two coupling capacitors are used to reduce the voltage at the gate terminal of the driving transistor in order to extend the data voltage range. The performance of the proposed pixel circuit is verified in an industrial 0.18-μm CMOS process. Simulation results show that the data voltage of the proposed pixel circuit ranges from 0.5 to 3.12 V, which is up to 4.37× wider than the previously published pixel circuits. The emission current error of the proposed pixel circuit varies from ?2.1% to 2.08%, under the condition of ±5 mV threshold voltage variation for the driving transistor. The maximum emission current error changes from ?10.36% to ?2.62% when the OLED turn-on voltage is increased by 5 to 20 mV due to device aging. Furthermore, the proposed pixel circuit only occupies a layout area of 8.1 μm × 4 μm.
关键词： Aging,high uniformity,compensation,organic light-emitting diode on silicon (OLEDoS),threshold voltage variation
更新于2025-09-16 10:30:52
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Pixel Circuit With Leakage Prevention Scheme for Low-Frame-Rate AMOLED Displays
摘要： This work proposes a new pixel circuit for active-matrix organic light-emitting (AMOLED) smartwatch displays with a low frame rate. Within the long emission period, the leakage current of a low-temperature polycrystalline silicon thin-film transistor (LTPS TFT) is reduced to suppress the distortion of the driving voltage at the gate node of the driving TFT. Based on the measured electrical characteristics of a fabricated p-type LTPS TFT, the HSPICE model is established to verify the feasibility of the proposed circuit. The analytical results indicate that the relative OLED current error rates are all below 4.73%, as the threshold voltage of TFT varies by ±0.5 V. Notably, the OLED current varies by only 2.94% during the emission period of 66.7 ms at a medium gray level, demonstrating the effectiveness of the leakage prevention scheme.
关键词： low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs),Active-matrix organic light-emitting diode (AMOLED),leakage current prevention
更新于2025-09-16 10:30:52