Search

This paper proposes a new eye‐tracking data correction method for the development of an automatic detection system for difficult‐to‐read characters in Japanese text. The proposed method, which adjusts the x‐axis of the eye, was compared with existing methods that adjust only the y‐axis. Data correction was performed for each method, and the detection accuracy of difficult‐to‐read Japanese characters was calculated and compared. The experimental results indicate that adjusting the x‐axis and y‐axis can improve the detection accuracy of difficult‐to‐read characters in Japanese text. This research advances easy correction techniques for difficult‐to‐read character detection in Japanese text and broadens the use of eye trackers, including low‐cost eye trackers. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

In this study, a novel and sustainable triboelectric material is successfully designed and developed by extracting keratin from recycled fur and combining it with chitosan to create a keratin/chitosan triboelectric nanogenerator (CK‐TENG) device. The device is designed for the simultaneous treatment of waste and the generation of green and clean energy, crucial for addressing global challenges. CK is prepared through a freeze‐drying method to overcome the weak mechanical properties of keratin and achieve a high surface contact area, which is important for triboelectric properties. The results showed that the output voltage is improved by 375% compared to the TENG without keratin, with values reaching 322 V under a 6 N. It produced a high power density of 14.4 W m−2 and excellent cyclic stability for more than 8000 cycles, which are crucial for practical applications. Further, the potential applications are also studied, and the results showed that it can turn on over 250 light‐emitting diodes (LEDs), display liquid crystal display (LCD), and charge capacitors under 6 N. Moreover, it is successful in harvesting energy from waste vibrations, acoustic energy, and as a shoe, and the electrical output is utilized to power electronic devices. Furthermore, the power density harvested by the device is higher than that of TENG devices made with keratin‐rich materials. Therefore, this study paves the way for the use of keratin‐based bio‐waste materials for clean and green energy production, which can play significant roles in applications such as the charging of electronic devices, biomedicine, sensors, and smart textiles. [ABSTRACT FROM AUTHOR]

The conditions for the growth of polycrystalline GeSn films on SiO2/Si(001) substrates by hot wire chemical vapor deposition are determined for the first time. The effect of the introduction of Sn into the Ge lattice on the morphology, structure, and transport properties of films is studied. GeSn films obtained at 300 °C have a uniform surface with a roughness of less than 1.0 nm. It is shown that the introduction of 5% Sn allows, without the use of recrystallization annealing, to significantly increase the hole mobility of polycrystalline GeSn films from 20 to 60 cm2 V−1 × s−1. despite the small grain size of 35 nm. Such films are of great interest for creating thin‐film transistors for active matrices' liquid crystal displays. [ABSTRACT FROM AUTHOR]

In this paper, a novel partial scan Gate Driver on Array (GOA) architecture with gate and cascade scan separated output (GCSS‐GOA) is proposed. Combined with a newly designed timing controller (TCON) IC and IP, dynamic local refresh at any position and with different refresh rate at different area on liquid crystal display (LCD) panel are achieved. The driving schemes for dynamic local refresh and the display image quality evaluation results are also presented. For power consumption, it can be reduced by up to 50% respectively for GOA and data drivers in dynamic local refresh mode under 60 Hz benchmark refresh rate. This technology is also applicable to OLED, LED, e‐paper and other display products. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrated the front NFC card swipe and touch display in Touch and Display Driver Integration (TDDI) liquid crystal display (LCD) through the technologies shown later. A new NFC sampling and noise reduction algorithm was used to reduce the generation of the ghost position and touch failure. The touch/NFC part‐time driving was applied to optimize the noise interference when NFC works. Meanwhile, we integrated the NFC antenna in the TDDI LCD and added a new display signal filter circuit and VCOM driver signal. In the NFC in‐cell demo, front NFC swiping distance of 60 mm is achieved. [ABSTRACT FROM AUTHOR]

The full‐screen mobile phone can be fabricated by integrating the camera beneath the screen, which needs the nanocomposite light guide plate (nano‐LGP) with exceptional transparency and light‐guiding properties simultaneously. Choosing an appropriate nanoparticle with a high refractive index and exceptional compatibility within the polymer matrix is crucial for producing the nano‐LGP. In this study, the high refractive index carbonized polymer dots (HRI‐CPDs) are synthesized through the solvothermal treatment, achieving a refractive index value of 1.7220 at 450 nm. Subsequently, the modified HRI‐CPDs (mHRI‐CPDs)/polymethyl methacrylate (PMMA) nanocomposites are fabricated by copolymerizing the mHRI‐CPDs with methyl methacrylate. Due to the high visible light transmittance and Rayleigh scattering characteristics when light passes through the nanocomposites, this kind of nanocomposites is suitable for serving as nano‐LGPs. The potential of carbonized polymer dots as light‐scattering unit is originally explored to improve surface illuminance and uniformity of nano‐LGPs. The best‐performing 4.3‐inch LGP with 1.0 wt.% doping content shows 15.8 times higher surface illuminance and 2.1 times higher uniformity than pure PMMA. This new type of LGP based on mHRI‐CPDs/PMMA nanocomposite holds tremendous promise in conjunction with advanced liquid crystal display technology. [ABSTRACT FROM AUTHOR]

We develop a measurement and evaluation system to quantify the halo effect of mini‐light‐emitting diode (LED) backlight liquid crystal displays (mLCDs). The validity and reliability of our halo measurement system was investigated through a human visual perception experiment. The results indicate that our halo measurement system can effectively distinguish the halo differences among different displays, with matching rate of 93.3% between our measurement and the human visual system. [ABSTRACT FROM AUTHOR]

A virtual qualification (VQ) model is proposed using a digital twin not only for verifying electrical properties of a liquid crystal display (LCD) but also for assessing the effect of environmental stresses. The digital twin is developed to reflect product specifications and distributions of manufacturing process data. The VQ model utilizes the digital twin to infer and verify the changes in electrical characteristic values in the internal circuit under a high‐temperature operating test. Additionally, a procedure is proposed for developing digital twins, and its effectiveness is demonstrated based on a case study of an LCD. The developed digital twin may also be used for similar LCD models for design verification. [ABSTRACT FROM AUTHOR]

Global energy policies have urged power consumption reductions for electronic devices. However, this is inconsistent with the users' need for enhanced device performance. In this work, converse flexoelectricity is used to reduce power consumption while maintaining the superior display image quality of liquid crystal display (LCD). The first 1 Hz‐refresh‐rate and flicker‐free fringe‐field switching (FFS) LCD for a 13.4‐inch laptop are reported. A noticeable brightness deviation is inevitable when driving voltage polarity is altered during low‐frequency driving, which is caused by the flexoelectric effect and voltage‐holding failure. The nature of the converse flexoelectric contribution of mesogenic systems with the optimum flexoelectric coefficients and molecular polarity, and developed materials based on findings is investigated. The quality of static images and videos at 1‐ and 10 Hz refresh rates, respectively, is maintained, and the measured power consumptions are reduced by 83% and 47% compared to that at a 60 Hz refresh rate, and minimal flicker level is measured by −68 dB. It is believed that this will serve as a new paradigm for energy consumption in electronic devices with superior display performance of FFS LCDs. [ABSTRACT FROM AUTHOR]

This study proposes a general strategy for constructing an asymmetric Fabry–Perot structure based on an ultra‐thin composite absorber, Ni/Ge2Sb2Se4Te1, to produce reflective full‐color structural colors with high brightness and purity. The composite absorber effectively enhances the strong interference effect of thin film, which can significantly reduce the reflection bandwidth of the target band and the reflectivity of the non‐target band. Under the premise of optimizing the five‐layer base structure, full‐color structural colors can be tuned by only changing the thickness of the LaTiO3 layer. Using the ion‐assisted electron beam evaporation technique, a simple and efficient film deposition process, six color devices (namely red, orange, yellow, green, blue, and purple) are successfully prepared with reflection peaks exceeding 90%. The chromaticity coordinates of the proposed high‐purity red, green, and blue (RGB) samples are (0.554, 0.339), (0.280, 0.600), and (0.164, 0.075), respectively. These coordinates are fairly close to the standard RGB color coordinates used in liquid crystal displays. This device has a simple structure with a novel material combination and a low production cost, which makes it feasible for mass production using just one coating run process. It has excellent application potential in various fields such as micro‐nano displays, anti‐counterfeiting measures, reflective color filters, and decorations. [ABSTRACT FROM AUTHOR]

Biomass‐based hydrogel is a promising flame‐retardant material and has a high potential for applications in transportation, aerospace, building and electrical engineering, and electronics. However, rapid vat photopolymerization (VP) 3D printing of biomass‐based hydrogels, especially that of all‐natural ones, is still rare. Herein, a new class of VP 3D‐printed hydrogels with strong covalent networks, fabricating using fully biomass materials and a commercial liquid crystal display (LCD) printer assembled with low‐intensity visible light is presented. Encouragingly, the highly ordered layer‐by‐layer packing structures provided by VP 3D printing technology endow these hydrogels with remarkable flame retardancy, exceptional temperature resistance, advantageous combustion behaviors, and favorable mechanical strength, in particular, giving them a better limit oxygen index (83.5%) than various biomass‐based hydrogels. The proposed approach enables the green design as well as the precise and efficient preparation for flame‐retardant materials, paving the way for the future flame‐retardant materials toward attaining green sustainability. [ABSTRACT FROM AUTHOR]

Robust amorphous glass protected CsPbBr3 (CsPbBr3@glass) perovskite quantum dots (PeQDs) with ultra‐pure green emission and superior long‐term stability are highly desirable for developing wide‐color‐gamut liquid crystal displays. However, most of the reported CsPbBr3@glass nanocomposites are subject to low external quantum efficiency (EQE). This work demonstrates that ZrO2 additive has an "accumulation" effect on the borosilicate glass network structure to promote in situ nucleation/growth of PeQDs inside glass rather than self‐crystallization. This effect is beneficial in reducing surface defects, improving the quality of PeQDs, and thus boosting radiative recombination of excitons. As a consequence, the as‐prepared CsPbBr3@glass shows a record EQE of up to 75% and can pass the accelerated aging tests at 85 °C/85% RH for 1000 h and blue light irradiation over 2000 h. Finally, a prototype display using CsPbBr3@glass‐based straight‐down backlit unit is designed and gains more favorable responses in blind selection tests for its high brightness of 2647 cd m−2 and high color purity of 88%. The findings will pave the way for realizing the commercial application of CsPbBr3@glass nanocomposite in PeQDs‐converted backlit display. [ABSTRACT FROM AUTHOR]

The utility of visible light for 3D printing has increased in recent years owing to its accessibility and reduced materials interactions, such as scattering and absorption/degradation, relative to traditional UV light‐based processes. However, photosystems that react efficiently with visible light often require multiple molecular components and have strong and diverse absorption profiles, increasing the complexity of formulation and printing optimization. Herein, a streamlined method to select and optimize visible light 3D printing conditions is described. First, green light liquid crystal display (LCD) 3D printing using a novel resin is optimized through traditional empirical methods, which involves resin component selection, spectroscopic characterization, time‐intensive 3D printing under several different conditions, and measurements of dimensional accuracy for each printed object. Subsequent analytical quantification of dynamic photon absorption during green light polymerizations unveils relationships to cure depth that enables facile resin and 3D printing optimization using a model that is a modification to the Jacob's equation traditionally used for stereolithographic 3D printing. The approach and model are then validated using a distinct green light‐activated resin for two types of projection‐based 3D printing. [ABSTRACT FROM AUTHOR]

The seeded growth method offers an efficient way to design core–shell semiconductor nanocrystals in the liquid phase. The combination of seed and shell materials offers wide tunability of morphologies and photophysical properties. Also, semiconductor nanorods (NRs) exhibit unique polarized luminescence which can potentially break the theoretical limit of external quantum efficiency in light emitting diodes based on spherical quantum dots. Although rod‐in‐rod core–shell NRs present higher degree of polarization, most studies have focused on dot‐in‐rod core–shell NRs due to the difficulties in achieving uniform NR seeds. Here, this study prepares high‐quality uniform CdSe NRs by improving the reactivity of the Se source, using a secondary phosphine, namely diphenylphosphine, to dissolve the Se power, along with the conventional tertiary phosphine, namely trioctylphosphine. Starting from these high‐quality NR seeds, this study synthesizes CdSe/CdxZn1−xS/ZnS core–shell NRs with narrow emission bandwidth (29 nm at 620 nm), high PLQY (89%) and high linear polarization (p = 0.90). This study then assembles these core–shell NRs using the confined assembly method and fabricates long‐range‐ordered microarrays with programmable patterns and displaying highly polarized emission (p = 0.80). This study highlights the great potential of NRs for application in liquid crystal displays and full‐color light emitting diodes displays. [ABSTRACT FROM AUTHOR]

Organic–inorganic manganese halide with environmentally friendly properties has become a new candidate material for backlight display applications. In this article, tetraethylammonium bromide (C8H20N)2MnBr4 is synthesized by a simple room temperature evaporation method. The tetrahedral coordinated Mn2+ demonstrates a green emission peak at 523 nm and a commendable photoluminescence quantum yield (PLQY) of 81.7%. To improve its stability, different proportions of Zn2+ are incorporated, leading to the discovery of (C8H20N)2Mn0.95Zn0.05Br4 as the most stable variant with a high PLQY of 84.3%. Additionally, by utilizing a sandwich method and double‐layer polyethylene terephthalate (PET) film encapsulation, the powder‐to‐binder ratio and thickness gradient are optimized, resulting in the ideal (C8H20N)2Mn0.95Zn0.05Br4@PET film with a powder‐to‐binder ratio of 1:2 and a thickness of 0.5 mm. Remarkably, the film exhibits superior stability against water, heat, and photo degradation. Finally, the light conversion film prepared from (C8H20N)2Mn0.95Zn0.05Br4@K2SiF6: Mn4+@PET composite material is applied to backlight display, and the color gamut covers 112% of NTSC 1953 and 83% of Rec. 2020. This study provides a feasible route for developing environmentally friendly, low‐cost, and high‐performance liquid crystal displays. [ABSTRACT FROM AUTHOR]

This study aims to develop a method that can detect the areas of Japanese texts that are difficult to read on a PC screen by analyzing eye movements. An effective method for detecting the areas of text that are difficult to read is to create a heatmap and consider the areas where the eye stays for longer than a fixation duration threshold (threshold). Usually, the threshold is determined through a 50 ms step search. However, since the eye stay time (fixation duration) for difficult‐to‐read text is longer than the fixation duration when reading smoothly, it is expected that steps that last longer than 50 ms are more effective at detecting the threshold. Furthermore, there are individual differences in the speed at which we comprehend text. In this study, we proposed a method that considers both the efficient search and individual differences among each subject. The experimental results showed that the threshold determined by the proposed method is more useful than the thresholds of 1000 and 800 ms that were used in a previous study, as well as the usual fixation duration of 250 ms. © 2023 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Recently, compactness of head-mounted display (HMD) products have been strongly required to improve comfortableness of user. The folded optics, socalled "Pancake optics", is suitable for realizing compact HMD, but there is a big drawback of lowering light efficiency. To overcome this problem, we propose a novel pancake-based HMD optics named "Double path pancake optics" using two light paths. The optical simulation is performed to find highly optimized optical properties such as thickness, and field of view (FOV). As a result of the simulation, we fixed the appropriate design. From our simple evaluation of both brightness and transmittance, we conclude that light efficiency of "Double path pancake optics" becomes 1.8 times higher than conventional pancake optics. We made the prototype using 1200 ppi high resolution liquid crystal display (LCD) and confirmed that the high image quality can be displayed. [ABSTRACT FROM AUTHOR]

Herein, we report two hybrid zero‐dimensional (0D) lead‐free metal oxide halides of [PPip]Sb2Cl6O (1) ([PPip]=1‐(2‐Pyridyl)piperazine) and [PmPip]Sb2Cl6O (2) ([PmPip]=1‐(2‐Pyrimidyl)piperazine). Compounds 1 and 2 are able to exhibit narrow blue light emissions excited by UV light with photo‐luminescence quantum yields (PLQYs) of 25.49 % and 24.71 %, respectively. Through systematical characterizations, these blue light emissions can be attributed to the radiative transition in conjugated organic cations. Benefiting from the highly efficient intrinsic blue emissions, compound 2 can be used as blue fluorophor to fabricate liquid crystal display. This work provides a new to assembly blue emitter through by virtue of the optical active organic cations in hybrid materials. [ABSTRACT FROM AUTHOR]

Al/PMMA/CS/PMMA/ITO structure devices are fabricated using polymethyl methacrylate (PMMA) and chitosan (CS) as dielectric layer materials. Its electrical characteristics and conductive mechanism are studied using its own physical characteristics to build a memristor true random number generator (TRNG). The generated true random sequence is optimized by a field programmable gate array (FPGA), and the optimized random number sequence is tested by the National Institute of Standards and Technology (NIST) to analyze its randomness. The pipeline structure is introduced to optimize the whole image encryption system, and the optimized random number sequence is used to realize image encryption inside the FPGA. Then, the encrypted image is displayed on a liquid crystal display (LCD) screen to realize random number generation and image encryption of all hardware. Finally, the encrypted image is analyzed. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) are one kind of photoluminescent materials with excellent properties, such as adjustable spectrum, narrow full width at half maximum (FWHM), and high color gamut. In this paper, a photoluminescent QDs printing paste suitable for light guide dots array applied in the backlight for liquid crystal display (LCD) was presented. The QDs printing paste was first prepared and characterized with different kinds of solvents. Then, triphenyl phosphite (TPP), a kind of antioxygen, was added into the QDs printing paste to improve the stability of the QDs printing paste. Finally, a QDs light guide plate (LGP) was fabricated by screen printing with QDs printing paste added with silicon dioxide (SiO2) light scattering particles. The color gamut of QDs LGP arrived 131.6%NTSC due to light scattering interaction between blue LED, red QDs, green QDs, and SiO2 particles. The results showed that the QDs‐chloroform printing paste had uniform light output and the highest photoluminescent peak intensity. Therefore, the composite screen printing paste has wide application prospects in the backlight of LCD, with the advantages of simple process, high production efficiency, and low cost. [ABSTRACT FROM AUTHOR]

During COVID‐19, there was increased use of handheld displays in educational settings. There is growing concern that eye health may be affected by prolonged exposure to the light‐emitting diodes used as frontlights or backlights in handheld displays. The potential impact of light exposure from tablet‐sized devices with different display technologies and various spectral outputs was assessed in an in vitro model using human retinal epithelial (ARPE‐19) cells. Cellular response was quantified by measuring reactive oxidative species (ROS) and by analyzing mitochondrial morphology. Control experiments established a baseline ROS response to hazardous blue light exposure and also that red light resulted in no detectable ROS response. Under identical conditions, ROS response increased with time for all devices. However, different device spectra caused ROS to accumulate at different rates. When operating the devices in the same mode (day or night), cells accumulated ROS two to three times more slowly on exposure to frontlit electronic paper displays compared to backlit liquid crystal displays. With increasing ROS accumulation, mitochondrial morphology shifted from elongate interconnected features typically observed under normal conditions to rounded disconnected features associated with oxidative stress response. [ABSTRACT FROM AUTHOR]

For the purpose of effectively solving the problems of manual inspection of thin‐film transistor–liquid crystal display (TFT‐LCD) with spot Mura high leakage rate and time consuming, this article proposes a visual detection method for LCD defects based on Mask R‐CNN convolutional neural network. In this article, a new feature extraction network is built by fusing ResNet with efficient channel attention (ECA) channel attention mechanism, and a new feature fusion network is constructed by adding ECA channel attention mechanism to Feature Pyramid Network (FPN). In the dataset of self‐made display defect images collected at the production site, the current more advanced segmentation network was compared qualitatively and quantitatively with our method, and the results showed that the proposed method was more accurate in detecting spot Mura, with a detection accuracy of 91%. [ABSTRACT FROM AUTHOR]

A polarization modulated directional backlight autostereoscopic display is proposed and demonstrated. The system consists of the orthogonally polarized backlight, the Fresnel lens array, a light shaping diffuser film, and a liquid crystal display (LCD) with a microphase retardation film. The autostereoscopic image pair carried by the directional light with different polarization directions is simultaneously projected to different spatial directions. The simulation and experimental results show that the directional projection of parallax images is realized for a high‐quality autostereoscopic display with large viewing angle and continuous viewing volume, hence making it suitable for practical applications. [ABSTRACT FROM AUTHOR]

Polymers and peptides have recently been considered as promising materials for piezoelectric energy harvesting because of their biocompatibility and enormous design possibility. However, achieving significant output voltages while meeting environmental safety requirements, low cost, and easy fabrication remains a major challenge. Herein, lipidated pseudopeptide incorporated poly(vinylidene fluoride) (PVDF) composite films are fabricated. Adding lipidated pseudopeptide (BLHA) increases the electroactive phase content, reaching the maximum for the 2 wt% composite film. The composite film containing 2 wt% BLHA manifests the highest dielectric constant and remnant polarization (Pr), among others. A piezoelectric energy harvesting device fabricated with this film generates open‐circuit output voltages up to 23 V, five times amplified output compared to pure PVDF. To the best of our knowledge, this material is superior among the peptide‐based piezoelectric energy harvesters reported in the literature. The device is flexible, durable, low cost, and sensitive to high and low pressures. It can power up multiple liquid crystal display panels when pressed with a finger. The non‐covalent interaction between BLHA and PVDF is the reason behind the composites' improved piezoelectric response. Density functional theory calculations also support this notion. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) have gained increased interest as highly conductive and transparent nanomaterials with numerous applications across various fields. Owing to their unique properties (e.g., optical transparency, electrical conductivity, mechanical characteristics, and ease of processing), AgNWs have been extensively investigated for application in light‐emitting diodes, solar cells, electrocatalysis, liquid crystal displays, wearable electronic devices, flexible nanosensors, and supercapacitors. In this review, recent advances in the synthesis of AgNWs (including the polyol, template, wet chemical, and photoreduction methods) are discussed, with a focus on their advantages and disadvantages in terms of AgNW structural regulation. Furthermore, the advantages and applications of AgNW composites, are comprehensively reviewed and analyzed, with a focus on energy storage and optoelectronics, sensors, electromagnetic interference shielding and absorbing materials, nanogenerators, and other applications. The prospects and challenges of AgNW composites in emerging applications are also proposed. [ABSTRACT FROM AUTHOR]

The defect of mura of thin film transistor liquid crystal display (TFT‐LCD) panel is small, and the gray change is unknown. In manual detection, mura is easily overlooked, which is time‐consuming and labor‐intensive. These factors resulted in our inability to properly assess and distinguish multiple mura defects on a single image in field inspections. Aiming at the above problems, this article proposes a multibackground TFT‐LCD mura defect visual inspection method. To obtain the optimal algorithm under high‐precision and high‐speed detection and to overcome the problem of missed detection of the YOLOV4‐tiny algorithm, the spatial pyramid pooling module and squeeze‐and‐excitation module are added on the basis of the original framework. On the one hand, the advantage of the improved algorithm in this article is to focus on the key information, so that the information before feature fusion is more abundant. On the other hand, adding spatial pyramid pooling in BackBone enables the network to perform multiscale pooling and fusion on the input feature layer, which greatly enhances the receptive field of the network and enables the network to extract richer feature information. Experimental results show that the improved YOLOV4‐tiny algorithm has an accuracy of 99.72% in TFT‐LCD mura detection, which is 0.99% higher than YOLOV4‐tiny, and the real‐time detection speed reaches 63.84 frames per second (FPS). At the same time, we overcome the problem of missed detection of YOLOV4‐tiny algorithm and meet the detection accuracy and real‐time requirements of TFT‐LCD mura detection tasks in multibackground environment. [ABSTRACT FROM AUTHOR]

The exploitation of the optimal optical properties of lead halide perovskite nanocrystals in optoelectronic devices is mainly hindered by the low stability of such materials. Here, a molten‐salts approach is developed to encapsulate CsPbBr3 nanocrystals (together with KNO3, NaNO3, and KBr inorganic salts) inside different nanoscale mesoporous SiO2 host matrices, having sizes between 100 and 300 nm. The comparison between optical properties and stability of the products, including the previously reported ≥600‐nm‐sized CsPbBr3/m‐SiO2 composite, indicates that 100‐nm‐sized CsPbBr3/m‐SiO2 particles feature the best stability against humidity, light irradiation and heat, and exhibit a green (peaked at 517 nm) narrow photoluminescence (full width at half maximum of 18 nm) with high quantum yield (77%). Such properties make these composite particles optimal green phosphors for down conversion liquid crystal displays (LCDs). Indeed, the authors demonstrate that a proof‐of‐concept 7‐in. LCD in which the green color conversion layer is a polymer film loaded with 100‐nm‐sized CsPbBr3/m‐SiO2 particles, features an optimal white emission (with correlated color temperature of 6861 K), that is close to the reference white point of NTSC, and covers 92% of NTSC standard color gamut area of CIE1931, higher than that of a reference commercial LCD (Dell XPS 15 7590 laptop). [ABSTRACT FROM AUTHOR]

Inorganic lead halide perovskite quantum dots (QDs) CsPbX3 (X = Cl, Br, or I) with superior optical and electronic properties are regarded as excellent materials for various optoelectronic devices. However, their instability significantly hinders their practical applications. Herein, composite films of CsPbBr3 QDs and polyimide (CsPbBr3@PI) are prepared using an in situ green synthesis method without other ligands and anti‐solvents. This strategy allows the formation of CsPbBr3 QDs and polymerization of polyimide monomers to occur simultaneously, which encapsulates the CsPbBr3 QDs with a protective PI layer. The CsPbBr3@PI film has narrowband green emission and excellent stability against air, water, and light. The emission intensity of a CsPbBr3@PI film is maintained at 93% and 90% of the initial intensity after exposure to air for 43 days and immersion in water for 14 days, respectively. In addition, the water contact angle is 105°, indicating that the film has good hydrophobicity. Surprisingly, the film is not broken after repeated bending (1 250 times), and its emission intensity is almost unchanged, which illustrates that the film has excellent flexibility. The good performance of the obtained CsPbBr3@PI films indicates their potential as a backlight source for flexible liquid crystal display applications. [ABSTRACT FROM AUTHOR]

Elaborate engineering of emitting wavelength of green down‐converter in the spectral range of ≈525–535 nm with narrow full‐width at half‐maximum (fwhm < 25 nm) is an essential prerequisite for faithfully reproducing colors in the quantum dot (QD)‐based backlit display. Herein, different from the previous complex synthesis for green films, FAPbBr3 perovskite QDs films are fabricated by a dual‐additive assisted in situ growth strategy. Both C6H5CH2CH2NH3+ and 1,4,7,10,13,16‐hexaoxacyclooctadecane additives are introduced to synergistically tune green emitting (≈525–535 nm) with the narrowest fwhm down to 21 nm and the highest photoluminescence quantum yield (PLQY) up to 99%. Improved nanocomposite film with excellent long‐term stability is used to construct a prototype liquid crystal display (LCD) with a wide color gamut (118% National Television System Committee and 88% Recommendation BT 2020), a high saturation, and a remarkable color rendition. The performance is superior to that of the commercial white‐LED‐based LCD, showing a great potential of the present green film for high‐definition display application in the future. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) is well known for supporting the manufacturing of composites through the 3D printing of lay‐up tools, sacrificial mandrels, trim molds, etc. The fused deposition modeling (FDM) is a pioneer in composite tooling. This technique is advantageous in many scenarios in which it is convenient to obtain hollow composite parts by dissolving sacrificial mandrels, removing the use of expensive and heavy metal molds. However, the effects that the removal process has on the thermomechanical properties of the composite must be considered. The convenience of another AM technique, liquid crystal display (LCD) printing, has also recently been demonstrated. The present work aims to compare three different techniques, FDM, fused filament fabrication (FFF), and LCD, each using different materials and, therefore, different mandrel removal processes. DMA analyses have highlighted the impact of some dissolution processes on thermomechanical properties. Further mechanical analysis is conducted to support what is found in the thermomechanical characterization tests. Finally, an economic analyses highlight the time and cost savings of some AM technologies compared to the conventional method for manufacturing composite parts. [ABSTRACT FROM AUTHOR]

Colloidal quantum wells (CQWs) are excellent candidates for lighting and display applications owing to their narrow emission linewidths (<30 nm). However, realizing their efficient and stable light‐emitting solids remains a challenge. To address this problem, stable, efficient solids of CQWs incorporated into crystal matrices are shown. Green‐emitting CdSe/CdS core/crown and red‐emitting CdSe/CdS core/shell CQWs wrapped into these crystal solids are employed as proof‐of‐concept demonstrations of light‐emitting diode (LED) integration targeting a wide color span in display backlighting. The quantum yield of the green‐ and red‐emitting CQW‐containing solids of sucrose reach ≈20% and ≈55%, respectively, while emission linewidths and peak wavelengths remain almost unaltered. Furthermore, sucrose matrix preserves ≈70% and ≈45% of the initial emission intensity of the green‐ and red‐emitting CQWs after >60 h, respectively, which is ≈4× and ≈2× better than the drop‐casted CQW films and reference (KCl) host. Color‐converting LEDs of these green‐ and red‐emitting CQWs in sucrose possess luminous efficiencies 122 and 189 lm W−1elect, respectively. With the liquid crystal display filters, this becomes 39 and 86 lm W−1elect, respectively, providing with a color gamut 25% broader than the National Television Standards Committee standard. These results prove that CQW solids enable efficient and stable color converters for display and lighting applications. [ABSTRACT FROM AUTHOR]

The ever‐increasing utilization of blue light‐emitting diode in the field of the display has brought great damage to human eyes. Here, we demonstrate a method that reduces the damage caused by high concentrations of short‐wavelength blue light. Our wide spectrum and low peak backlight technology are based on replacing the existing common blue chip with a combination of shortwave blue‐chip and long‐wave blue chip. At the same time, a large number of blue‐filtering dye particles are coated on the optical film to reduce high‐energy blue light and achieve the effect of protecting the eyes. Therefore, our project can achieve up to 25 nm FWHM and a 50% reduction in peak blue light that is close to the continuous spectrum of natural light in the blue wavelength region. Numerical and experimental results, in a good agreement, demonstrate good performance of the proposed approach in liquid crystal display, with potential applications to eye‐friendly display. [ABSTRACT FROM AUTHOR]

The demand for high‐performance displays is continuously increasing because of their wide range of applications in smart devices (smartphones/watches), augmented reality, virtual reality, and naked eye 3D projection. High‐resolution, transparent, and flexible displays are the main types of display to be used in future. In the above scenario, the micro‐LEDs (light‐emitting diodes) display which has outstanding features, such as low power consumption, wider color gamut, longer lifetime, and short response‐time, can replace traditional liquid crystal displays and organic LEDs‐based display technologies. However, to attain a remarkable position in future display technology, the micro‐LEDs need to overcome problems associated with mass transfer and its high cost of manufacturing. Besides micro‐LEDs, the other option for future displays includes the usage of color conversion medium (phosphor/ quantum dots) to convert some of the blue light into other colors. In this review, the various mass transfer display technologies and color conversion strategies which are being used for the realization of a full‐color display are discussed. [ABSTRACT FROM AUTHOR]

A 2.9‐inch 2K2K (1058 ppi) panel using low‐reflection metal black matrix (BM) has been developed. We confirmed lower reflectance of LCD with low‐reflection metal BM that is required for VR headsets recently and also confirmed that there was no adverse effect on the display optical characteristics. We have shown that a thinner BM allows us to design more transparent pixels by increasing the aperture ratio or to increase the color viewing angle. [ABSTRACT FROM AUTHOR]

Thin film transistors (TFTs) are ranked as one of the promising field‐effect transistors in the electronic industry. TFTs showed a great potential in many applications where liquid crystal displays, touchscreens, and biosensors are of the leading. In the current study, we are demonstrating a numerical carrier transport model based on finite element method (FEM), to investigate InGaZnO (IGZO) based TFTs. Amorphous silicon TFT has been simulated as a bare device. The impact of scaling down the dimension of the TFT, up to 30 nm channel length, on the output performance characteristics of the transistor has been addressed. Additionally, the effects of active semiconductor layer doping concentration and oxide layer thickness have been investigated. Moreover, a novel approach is introduced to correlate the selected input design parameters with a set of characteristic outputs including threshold voltage, on/off current ratio, and subthreshold swing. The proposed model correlates input and outputs using a characteristic matrix with nine coefficients, making it possible to predict, that is, interpolate, the characteristic outputs within the system boundaries. The suggested model was verified with respect to input data as well as data from the literature showing a very acceptable agreement. [ABSTRACT FROM AUTHOR]

Self‐assembly of colloidal nanocrystals into ordered superlattices is a powerful approach to enable novel collective properties which are not available in individual colloids. However, to date, it remains a major challenge to develop a practical route to modulate such collective properties for potential photonic applications. Herein, it is shown that the collective emission properties in colloidal quantum well (CQW) superlattices, including emission color and anisotropy, can be effectively modulated in a binary host–guest architecture. The experimental and theoretical results reveal that excitons of the host (i.e., the undoped CQWs) generated by photoexcitation can be controllably harvested by the guest (i.e., the Cu‐doped CQWs) for light emission, owing to an exciton hopping assisted exciton trapping process. Such a nano‐building block with tunable collective optical properties may enlighten novel colloidal material‐based photonic applications, including optical anti‐counterfeiting, next‐generation liquid crystal displays, and multifunctional biological markers. [ABSTRACT FROM AUTHOR]

Active matrix (AM) mini‐LED backlight units (BLUs) based on amorphous silicon (a‐Si) thin‐film transistor (TFT) on a glass substrate for 75‐inch 8K liquid crystal displays (LCDs) are developed, with each consisting of 5184 local dimming (LD) zones. The 75‐inch 8K LCDs perform a high dynamic contrast ratio of 1,000,000:1 and high typical brightness of more than 1000 nits with 10% capable screen area. In addition, the LCDs show an excellent high dynamic range (HDR) and a real black state, which are comparable to that of other high‐end displays (dual cells and organic light‐emitting diode displays [OLEDs]). Also, the mini‐LED BLUs feature a low fabrication cost. [ABSTRACT FROM AUTHOR]

Narrow‐band green‐emitting phosphors have attracted increasing attention for designing wide color gamut devices with high quality. However, the development of highly efficient and thermally stable green phosphor with narrow band is still a significant challenge. Herein, a novel green narrow‐band phosphor, BaZnAl10O17:Mn2+ (BZAO:Mn2+) is developed owing to the weak coupling interaction of Mn ions in the highly symmetric BZAO with rigid structure. Upon 450 nm excitation, BZAO:0.20Mn2+ shows an intense green emission peaking at 516 nm with a full width at half maximum of 31 nm, a color purity of 78%, and an internal quantum efficiency of 85.59%. Moreover, when temperature rises to 423 K the emission peak intensity still maintains 95% of that at 298 K, and the color and brightness present no obvious degradation, indicating an extremely indistinctive thermal quenching behavior. The fabricated light emitting diode (LED) device exhibits bright white light with corrected color temperature (CCT) of 6732 K and its color gamut (CG) value reaches as wide as 110% National Television System Committee (NTSC) standard. These results demonstrate BZAO:0.20Mn2+ can be considered as a potential efficient phosphor with green narrow‐band emission for wide color gamut backlight. [ABSTRACT FROM AUTHOR]

Due to the limitations of the lens array of the integral imaging display, the viewing angle and resolution are mutually restricted in space, and are difficult to improve at the same time. We propose an integral imaging system based on dual time division multiplexing using a liquid crystal aperture array to improve viewing angle and resolution simultaneously. A liquid crystal panel is introduced into the traditional integral imaging display system as an adjustable aperture array, which is used to change the imaging effect of the micro‐lens array and to realize the dual time division multiplexing of elemental image pixels. The liquid crystal aperture array is controlled to gate different lenses and different positions on the lens at different times, then the corresponding elemental image array is rendered. Thus, the spatial constraints of viewing angle and resolution are transformed into the time domains by multiplexing. Based on the proposed scheme, this paper also proposes a synchronous rendering algorithm for elemental image array and aperture array patterns in the different multiplexing periods. To verify the feasibility of the scheme, we built a prototype display and the experimental results verified that our method achieved certain improvements in viewing angle and resolution. [ABSTRACT FROM AUTHOR]

Conducting remote laboratory‐based courses in electronics is a major challenge primarily because of the hardware requirements. This paper describes a laboratory course on information display technologies specially designed and implemented for remote learning. The course was successfully offered during the COVID‐19 lockdown and has an online instruction component to introduce the concepts, as well as a laboratory part involving hands‐on work. The course covers experiments on fundamental concepts related to perception and color, liquid crystal displays (LCD), light‐emitting diodes (LEDs), and a final project where a mechanical display is designed and built. Course assessment based on an anonymous survey shows the hands‐on work enhanced the student learning and improved course understanding from an average of 2.5/5 measured at the start of the course to 4/5 at the end. [ABSTRACT FROM AUTHOR]

It remains a critical challenge to develop narrow‐band emitters for wide color gamut displays. Herein, it is designed by the selective site occupancy engineering and an unprecedented narrow‐band green‐emitting phosphor is prepared through chemical substitution. By introducing Ga3+ ions into Sr2LiAlO4:Eu2+ phosphor, the distribution of Eu2+ ions in Sr1 and Sr2 sites is effectively controlled, and only one type of luminescent centers Eu2+(Sr1) is remained in Sr2LiAl0.6Ga0.4O4:Eu2+ due to the compression effect of Sr2O8 polyhedra. Sr2LiAl0.6Ga0.4O4:Eu2+ phosphor presents an extremely narrow‐band green emission centered at 512 nm with a full‐width at half‐maximum of only 40 nm. The wide color gamut (107% National Television System Committee) of the as‐fabricated white liquid crystal displays and the vivid figures captured from the projector demonstrate the potential application of narrow‐band emitter for wide‐color gamut displays. This work provides the design principles of realizing narrow‐band emission by selective site occupancy engineering and can set the stage for the exploring of Eu2+‐activated phosphor for high definition displays. [ABSTRACT FROM AUTHOR]

Light‐emitting displays become the future direction of display technology for the radical requirement of reducing energy consumption. Here, an approach of fabricating a luminescent liquid crystal (LE‐LC) display device without polarizers and alignment layers is reported, achieved by using an aggregation‐induced emission (AIE)‐active LE‐LC mixture. Through studying the relationship between emission of the LE‐LC at several orientation modes and the concentration of the AIE‐featured fluorescent dye, the difference of fluorescence at aggregation state is revealed. When the concentration of the fluorescent dye is high enough, the emission of the planar‐aligned LE‐LCs is ≈4 times of the vertical‐aligned LE‐LCs. An electronically controlled LE‐LC cell is thus constructed, in which the homeotropic alignment of liquid crystals is induced by doping of CuInS2 nanoparticles. Therefore, this simple LE‐LC display avoids the use of polarizers and alignment layers, raising the exciting possibility of development of high efficiency and low energy‐consumption LE‐LC devices. [ABSTRACT FROM AUTHOR]

The improvement of high‐performance narrow‐band green phosphors in backlight display applications is still a major challenge. Based on the UCr4C4 type of oxide phosphor, the high‐performance narrow‐band green phosphors Rb3M(Li3SiO4)4:Eu2+ (M = Rb or Na) are studied in different luminous positions. Benefiting from the replacement of Rb by Na, the change of the local environment in the crystal structure of Rb3Na(Li3SiO4)4:Eu2+ (R3NLSO:Eu2+) leads to the decrease of Stokes shift, which improves the quantum efficiency. Moreover, change in the local environment enhances the structural rigidity, which makes the thermal and chemical stability better. The R3NLSO:8%Eu2+ phosphor presents a narrow‐band green emission centered at 527 nm, excellent thermal stability (102% @150 °C of the integrated emission intensity at room temperature), and high internal/external quantum efficiency (85.3%/40.4%). The white light‐emitting diode (wLED) using R3NLSO:8%Eu2+ phosphor presents a superior luminous efficiency of 128.3 lm W‐1 and a wide color gamut. All the results indicate that R3NLSO:8%Eu2+ green phosphor has great application prospects in the field of liquid crystal display. This work also provides important guiding significance for the optimization of alkali metal element type of phosphors. [ABSTRACT FROM AUTHOR]

To enhance display performance in automotive applications subjected to harsh conditions, silicone polymer was used to address crucial interfacial issues such as touch mura and yellow mura in optical stack design. Mura refers to luminance non‐uniformity of a display device. Five different siloxane polymer compositions were prepared as optical laminating materials with different mechanical characteristics, such as hardness, shear modulus, and damping factor. The structures of the polymers were adjusted by varying the H/vinyl ratio, hydrogen source ratio between crosslinks, and terminal‐group reaction. To investigate the influence of mechanical properties on the performance of the polymers as laminating materials for displays, they were used as a lamination layer between a touch screen panel and liquid crystal display (LCD) module. The devices' capacity to handle thermal stress under thermal shock conditions and degree of luminance non‐uniformity associated with touch action were assessed. [ABSTRACT FROM AUTHOR]

All‐inorganic perovskite quantum dots (QDs) have emerged as a new category of low‐cost semiconducting luminescent materials for optoelectronic applications. However, their poor stability has become the main challenge that impedes their potential applications. Herein, Ni‐doped CsPbBr3 QDs with lead phosphate (Pb3(PO4)2) shell through surface sacrificial coating (c‐Ni‐CsPbBr3) have been developed based on a modified thermal injection approach. The synergistic effect of Ni doping and Pb3(PO4)2 coating effectively improves the stability and optical performances of CsPbBr3 QDs, including photoluminescence (PL) intensity, the average lifetime, and PL quantum yield (QY). Thus, the c‐Ni‐CsPbBr3 QDs demonstrate the full width at half maxima (FWHM) and PLQY being 18.42 nm and 90.77%, respectively. The PL intensity of c‐Ni‐CsPbBr3 can be maintained at 81% of its original value after being heated at 100 °C for 1 h. No phase transformation can be observed after being stored under ambient conditions (25 °C, 60% relative humidity (RH)) for 21 days. In addition, by combining green c‐Ni‐CsPbBr3 QDs, red CdSe‐based QDs and the blue GaN chip, a QD enhancement film (QDEF) is fabricated to form a liquid crystal display (LCD) backlit with a wide color gamut covering cover 121% of the National Television System Committee (NTSC) standard. [ABSTRACT FROM AUTHOR]

All‐inorganic perovskite quantum dots (QDs) have emerged as a new category of low‐cost semiconducting luminescent materials for optoelectronic applications. However, their poor stability has become the main challenge that impedes their potential applications. Herein, Ni‐doped CsPbBr3 QDs with lead phosphate (Pb3(PO4)2) shell through surface sacrificial coating (c‐Ni‐CsPbBr3) have been developed based on a modified thermal injection approach. The synergistic effect of Ni doping and Pb3(PO4)2 coating effectively improves the stability and optical performances of CsPbBr3 QDs, including photoluminescence (PL) intensity, the average lifetime, and PL quantum yield (QY). Thus, the c‐Ni‐CsPbBr3 QDs demonstrate the full width at half maxima (FWHM) and PLQY being 18.42 nm and 90.77%, respectively. The PL intensity of c‐Ni‐CsPbBr3 can be maintained at 81% of its original value after being heated at 100 °C for 1 h. No phase transformation can be observed after being stored under ambient conditions (25 °C, 60% relative humidity (RH)) for 21 days. In addition, by combining green c‐Ni‐CsPbBr3 QDs, red CdSe‐based QDs and the blue GaN chip, a QD enhancement film (QDEF) is fabricated to form a liquid crystal display (LCD) backlit with a wide color gamut covering cover 121% of the National Television System Committee (NTSC) standard. [ABSTRACT FROM AUTHOR]

In this paper, a precise and effective computational method for moire patterns' simulation and prediction of liquid crystal display (LCD) metal mesh touch panel based on the transmittance calculation of LCD's sub‐pixel is proposed. Firstly, we analyze the actual physical model and build our simulation model. Secondly, we explain the form reason of moire phenomenon and establish the transmittance calculation formula. Finally, we demonstrate the accuracy and validation of our simulation approach by practical experiment. The experimental results show that the simulation matching rate is about 88.2%, and the simulated graphs are extremely similar to the actual moire pattern. We can evaluate the moire degree with our new method; this research is significant to touch panel's production. [ABSTRACT FROM AUTHOR]

The effect of temperature on optical performance of a dual‐layer liquid crystal display (LCD) is investigated by considering LC material parameter and structural deformation of LC panels simultaneously. First, the optical anisotropy of LC material under the influence of temperature is calculated theoretically. Then, the thermal deformations of the dual‐layer LC panels caused by temperature are simulated. Combined with the two factors, the change in optical performance of a dual‐layer LCD under the influence of temperature can be analyzed. In white state, the color in the central area of a dual‐layer LCD is shifted towards blue, and a yellowish border in the edge area may appear. In gray or black state, there may be a light leakage in the edge area of a dual‐layer LCD under the influence of temperature. [ABSTRACT FROM AUTHOR]

A thin‐film transistors (TFTs) integrated gate driver circuit with bifunctional capacitors for in‐cell touch with horizontal blanking display mode is proposed in this paper. The coupling capacitor, which conventionally enables low‐level‐maintaining parts in display periods, is reused to store transfer charges during touch detection periods. Consequently, only nine TFTs and two capacitors are used for a single stage of the proposed gate driver for in‐cell touch display. Furthermore, the bifunctional capacitor scheme not only avoids the driving TFT from long‐time voltage stress but also suppresses the transfer charges leakage effectively. Therefore, the variation ratios of rising/falling time between adjacent gate driver stages are suppressed within 6%. For a 5.7‐in. display with HD+ resolution, the layout of a single gate driver stage is 623 μm (width) × 171 μm (height). The proposed gate driver circuit has been prepared with the state‐of‐the‐art hydrogenated amorphous silicon (a‐Si:H) TFT manufacturing process. The measured results verified the circuit functions. The gate driver output waveforms are well maintained and being almost independent of touch detection time interval from 100 to 300 μs. [ABSTRACT FROM AUTHOR]

There are kinds of defects that may appear in the process of Liquid Crystal Display (LCD) manufacturing, which cannot be effectively detected, owing to the uneven illumination, low contrast, and miscellaneous patterns of defects. To improve the efficiency of defect detection and ensure the quality of LCD, three visual real‐time detection methods are adopted for detecting six different defects in multiple backgrounds, where image preprocessing methods are used to highlight the defects and facilitate the segmentation and detection. Specifically, the interclass variance (OTSU) method is used to segment and mark Liquid Crystal Display (LCD) Mura and scratch defects in six kinds of solid color backgrounds; the method and the connectivity‐4 judgment criteria are adopted to label edge defects in grid display background; the gray mean and standard deviation of the segmented subregions are calculated to recognize the color gradation defect in the 32‐level gradation display background. Experimental results show that LCD Mura defects and scratches can be segmented more completely by the proposed method compared with the benchmark methods, and the edge defects can be identified accurately by the OTSU‐based method and particle‐based morphological processing with grids as the detection background, and the color gradation can also be recognized with the 32‐level gray gradation as the background. [ABSTRACT FROM AUTHOR]