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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]

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]

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]

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]

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 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]

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]

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]

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]

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]

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]

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]

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]

Recently, "liquid crystal display (LCD), organic light‐emitting diode (OLED), or micro‐light‐emitting diode (LED): who wins?" is a heated debatable question. In this review article, we provide a comprehensive overview of these three promising display technologies through nine display performance indicators, including ambient contrast ratio, motion picture response time, viewing angle and angular color shift, color gamut, resolution density, power consumption, cost, lifetime, and thin profile and panel flexibility. The advantages and disadvantages of each technology are analyzed, and their future perspectives are discussed. [ABSTRACT FROM AUTHOR]

We have developed a new reverse dispersion retardation film with a thickness of 4 μm for IPS panels, which achieves excellent viewing angle performance, notably for oblique contrast ratio and color. HDR‐IPS panels applied this reverse retardation film could achieve a significant improvement of the halo viewing from oblique angle. [ABSTRACT FROM AUTHOR]

We propose to apply short‐range lurch control in‐plane switching (SLC‐IPS) as a fast response liquid crystal display (LCD) mode to virtual reality applications, where fast response times and high resolutions are essential. In this study, we discuss the SLC‐IPS electrode structure optimized for high‐resolution virtual reality applications. To maintain transmittance at high resolutions, we developed a one‐sided branch electrode structure with convex parts. The issue of slow response times can be resolved using the convex part of the electrode structure by analyzing the imaginary boundaries characterizing the SLC‐IPS. Thus, a response time of less than 2.2 ms can be obtained over all tones using a 1001‐ppi high‐resolution SLC‐IPS LCD. [ABSTRACT FROM AUTHOR]

We propose a wide‐viewing integral imaging display. It consists of an organic light‐emitting diode, a barrier array, and a liquid crystal panel. The organic light‐emitting diode generates the rectangular light sources, and the liquid crystal panel displays the elemental images. The barriers are introduced to separate adjacent rectangular light sources and corresponding elemental images. Lights emitting from the rectangular light sources only illuminate the corresponding elemental images. The horizontal viewing angle and the luminance are both enhanced by increasing the horizontal width of the point light source. A prototype of the proposed integral imaging display is developed, and the experiment results agree well with the theory. [ABSTRACT FROM AUTHOR]

A structure of copper/molybdenum/titanium conductive layer with a very long tail of titanium under copper is introduced to eliminate the depolarization problem from metal microstructures for the first time. The electric field of light is blocked by the 20‐nm thin titanium tail (200 nm) layer, and the depolarization of light at the corner of the conductive line disappears in the liquid crystal display (LCD). As a result, the contrast ratio of the LCD is increased by 18%. [ABSTRACT FROM AUTHOR]

We proposed adaptive pre‐charge driving (APD) technique that is appropriate for large‐size and high‐resolution liquid crystal display (LCD) panels for TVs to compensate the shortage of charging voltage to a pixel. APD technique enables to realize LCD panels of 8K resolution even though thin‐film‐transistor (TFT) is amorphous‐Si. Recently, this APD renamed line‐overdrive (line‐OD), and it has been reported to be applied to 8K‐LCD panels, and its technical value is increasing. This paper describes an image‐sticking phenomenon with APD. We have made clear that this phenomenon is triggered by the residual DC that was created by the charging performance to the pixel of positive polarity being inferior to the charging performance to that of negative polarity. To solve this issue, it further explains how best to optimize the pre‐charge table for positive and negative polarities, respectively, by effectively using the high‐precision pixel simulation. [ABSTRACT FROM AUTHOR]

We have developed a 17‐inch laser backlight in‐plane switching liquid crystal display satisfying the main BT.2020 specifications, which are 8K, 120‐Hz driving, and a BT.2020 wide color gamut. The color gamut of the developed in‐plane switching liquid crystal display covers 98% of the BT.2020 wide color gamut, thanks to a laser backlight and appropriate color filters. The liquid crystal response time of 5 ms, which is sufficient for 120‐Hz driving, is achieved by adapting a faster in‐plane switching liquid crystal display, namely, the short‐range lurch control in‐plane switching liquid crystal display. [ABSTRACT FROM AUTHOR]

Since the introduction of the first modern (i.e., digital) vehicle displays, designers and manufacturers have made significant advances in technologies that improve image quality and enhance unit durability. Typically, these advances have been targeted and discrete. For example, to increase brightness, high efficiency light control films were deployed; to reduce nighttime windshield glare, a light‐directing louver film was incorporated into the liquid crystal display (LCD) backlight. While this targeted approach to vehicle display concerns has advanced performance—in many cases impressively—it may have reached the limits of its effectiveness. For displays based on the most common head‐up display (HUD) architecture, shortcomings are often interrelated. As such, they require a holistic or cabin human machine interface (HMI) ecosystem approach that recognizes this interplay and, where possible, addresses multiple issues simultaneously. Several new films, in concert with existing film technologies, show how a cabin ecosystem strategy can be implemented. [ABSTRACT FROM AUTHOR]

A transflective blue‐phase liquid crystal display (TRBP‐LCD) based on fringe in‐plane switching (FIS) electrodes is proposed. The proposed structure generates combined fringe and in‐plane electric fields that cause more liquid crystal (LC) molecules to reorient almost in plane above and between the pixel electrodes. The fringe field is mainly generated in the transmissive (T) region, and the horizontal electric field is mainly generated in the reflective (R) region. By optimizing the width of the pixel electrodes and the gap between two adjacent pixel electrodes, the different electric field intensity in the T and R regions contribute to balance the optical phase retardation between the T and R regions. As a result, the proposed TRBP‐LCD exhibits a low operating voltage and high optical efficiency, while it preserves a relatively simple fabrication process. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the impact of the blue light from the visual display terminal (VDT) on visual search tasks. We assessed the quantity of the blue light from medical imaging diagnoses (medical‐grade) liquid‐crystal display (LCD) and general (personal computer‐grade) LCD for the VDT work, both equipped with the blue light reduction function. Then, we measured the visibility of display by evaluating the correct answer rate and reaction time of visual search tasks. The quantity of the blue light was proportional to the luminance of the display. When the blue light reduction function was used during the VDT work, the blue light at the peak wavelength was reduced by about 56%. Though the luminance of the display reduced, the visibility of the display was not decreased. These findings suggest that the blue light reduction on the LCD could work efficiently in the VDT work, maintaining the visibility of the display. [ABSTRACT FROM AUTHOR]

A new architecture for a thin (2‐cm depth) rear projection display is described. In order to achieve this small depth, a very high density of rear projectors is used. Three prototype displays using rear projectors on both 5‐ and 2‐cm pitch arrays are described. The displays can achieve an effective screen pixel pitch of as small as 0.5 mm, which makes this technology competitive in terms of resolution with fine pitch LED displays; however, orders of magnitude fewer LEDs are required: Each rear projector requires only one white LED and a color liquid crystal light modulator. In the three prototypes, the projector light modulators utilize 101‐cm (40 in.), 80‐cm (31.5 in.), and 60‐cm (24 in.) diagonal liquid crystal display glass. To minimize cost, no lenses are utilized for the rear projectors. An RGB LED array may augment the projector array, which provides a low resolution component of the image onto which the high resolution component is superimposed by the projector array. Edge gaps between active areas on adjacent LCD glass units are completely eliminated by the rear projection approach enabling low profile wall‐size seamless displays. Display contrast depends on rear projection screen design. [ABSTRACT FROM AUTHOR]

Camera Monitor Systems (CMSs), for example, for backup cameras or mirror replacements, become increasingly important and already cover safety aspects such as guaranteed latency and no frame freeze. Today's approaches deal only with supervision of the digital interface, LCD backlight, and power supply. This paper introduces methods for advanced safety monitoring of panel electronics and optical display output that aim to enable future CMS based automotive use cases. Our methods are based on correlation of physical measurements with predicted values derived from a corresponding display model. This model was made via calibration measurements and many test patterns. Correlation of the monitoring results with predicted values corresponds to the probability that the RGB data are shown as intended. This implies that an overlying system, an Automotive Safety Integrity Level (ASIL) Prepared Video Safety System (APVSS), ensures that only safety verified RGB data are provided to the panel electronics. In case of failures, our methods enable a safe system state, for example, by deactivating the panel. An additional challenge is to allow graceful degradations, a safe but slightly degraded image may provide a better customer experience compared with no information. We successfully verified our approach by a fully functional prototype and extensive evaluation towards "light‐to‐light" (camera to display output) supervision. [ABSTRACT FROM AUTHOR]

Birefringent light‐shaping films (BLSFs) for mini‐LED backlit liquid crystal displays (LCDs) are proposed and experimentally demonstrated by passive polymer‐dispersed liquid crystal (PDLC) films. Such films show angle‐selective scattering properties, achieved by proper material engineering and good vertical alignment of liquid crystals. They only respond to angles rather than spatial locations. By directly adhering the BLSF onto a LED, the angular intensity distribution of light can be tailored from Lambertian‐like to batwing‐like. Further simulation proves that by engineering the angular distribution, a fewer number of LEDs or equivalently a shorter light‐spreading distance is required to maintain good uniformity. These BLSFs are expected to find widespread applications in emerging mini‐LED backlit LCDs and shed light on designing other light‐shaping films in the future. [ABSTRACT FROM AUTHOR]

Curved liquid crystal display (LCD) suffers from an issue of uneven brightness among the vertical‐alignment LCD panels based on thin glass substrates. In this work, we investigated its origin through optical simulation and successfully realized uniform brilliance for 27‐inch curved LCD panels. The optical simulation revealed that the dark areas on the bending sides of the curved LCD panel originated from the reduced azimuth angle of the liquid crystals (LC) next to the ITO trunk. This issue could be resolved by decreasing the pretilt angle of the LC on the color filter side. Through developing pretilt angle tuning technologies, we experimentally verified that the uniform brilliance could be achieved for 27‐inch curved LCD panels with 900‐mm curvature on thin glass substrates. [ABSTRACT FROM AUTHOR]

Plastic liquid crystal displays (LCDs) termed sheet LCDs with transparent polyimide (PI) substrates were constructed. There is a lot of potential to expand the use of these LCDs in LCD applications. Herein, we investigated a structure for sheet LCDs such as high‐density main post spacers (PSs) and PI substrates with the aid of a barrier layer to control the residual stress and protect the liquid crystal from moisture. Drawing on this, we propose an ultra‐narrow border LCD that makes of the developed sheet LCDs. The most significant improvement is that the four borders of the LCD can be folded to wrap the backlight unit. This LCD was based on various new techniques, including the use of plastic substrates, processing of polarizer films, control of the neutral surface of a bending component based on the sealant width, and the use of a cover glass with a lens effect. We believe that these novel LCDs will be useful in numerous new applications. [ABSTRACT FROM AUTHOR]

Multiplane displays are capable of displaying 3D scenes with correct focus cues by creating multilayer 2D images in the display volume. Hence, such a 3D display technique could effectively address the accommodation‐vergence conflict (AVC) problem, which is prevalent in augmented reality (AR) displays. In this paper, we review the recent progress on multiplane AR displays based on liquid crystals (LCs) for AR applications. The working principle of multiplane AR displays is illustrated, the electro‐optical properties of the tunable LC devices are investigated and display prototypes are demonstrated. Finally, we discuss the prospects and challenges of multiplane AR displays based on LCs. [ABSTRACT FROM AUTHOR]

We have mass production on one kind of liquid crystal display (LCD) device with hybrid viewing‐angle (HVA), which can be switched between the wide viewing‐angle (WVA) and narrow viewing‐angle (NVA) by one button. This device adopts the single cell design that with lower cost, and utilizes the optical properties of electrically tilted LC to achieve the function of NVA display. An issue has received less attention in the past and been indeed found in the production process. It is that the off‐axis color shift will appear in NVA mode. We put forward one method to improve this issue here, which is combined with the concepts of Gray Frame Insertion (GFI) and Impulse‐type driving. By switching the voltage between two different γ values, the color shift will be perfected on the produce. [ABSTRACT FROM AUTHOR]

A single‐cell‐gap transflective liquid crystal display with a nonuniform electric potential is demonstrated. The top substrate has a top planar common electrode, a transparent dielectric layer with a general dielectric constant is coated on the bottom substrate, and two planar pixel electrodes with the same size are coated on the dielectric layer and the bottom substrate, respectively. With the different gaps between the two planar pixel electrodes and top planar pixel electrode, the nonuniform electric potential from the transmissive region (T region) to the reflective region (R region) is generated, while a bumpy reflector is coated under the bottom substrate. In this device, with the dielectric layer, the pixel and common electrodes generate a strong electric potential in the T region and a relatively weak electric potential in the R region. Consequently, the T and R regions accumulate the same optical phase retardation. The simulation results show that the display exhibits reasonably low operating voltage, high optical efficiency, and well‐matched voltage‐dependent transmittance and reflectance curves. Besides, the fabrication process and the driving mode of the transflective liquid crystal display are relatively simple, and it is suitable for mobile applications. [ABSTRACT FROM AUTHOR]

Liquid crystal displays are now indispensable in everyday life. The display characteristics considerably depend on the configuration of liquid crystal (LC) molecules and interactions between the LC molecules and an alignment film surface. In this paper, we introduce various methods to control parameters that dominate the LC alignment. These parameters include order parameters, the pretilt angle, the director direction, and surface anchoring strength. We also introduce their evaluation methods. In particular, recent alignment film‐free technology is explained in detail. In addition, details of how these parameters are related to the display characteristics, particularly wide viewing angles and fast response characteristics, are described primarily with reference to recent technologies. [ABSTRACT FROM AUTHOR]

Nowadays, thin‐film transistor liquid crystal displays (TFT‐LCDs) have realized high reliability of display characteristics by improving liquid crystal (LC) materials and cell fabrication processes. In order to improve display reliability, measurement methodologies are important to see the progress of improvement of materials and processes; thus, our group has proposed voltage holding ratio (VHR), ion impurity, residual direct current (DC) and elastic constants for LC cells, and the optical anisotropy of an alignment layer on indium tin oxide (ITO) glass substrate for LCD industry. In case of an ion impurity, we have succeeded in measuring the ion impurity amount in TFT‐LCD. Furthermore, we have recently proposed ion impurity measurement methodology for beyond LCD applications that are organic light emitting diode (OLED) and organic photovoltaics (OPV). In this review, I introduce each measurement methodology for LCDs and beyond LCDs in detail. [ABSTRACT FROM AUTHOR]

We will introduce the development trend of colorant and color technology along the grown of display industry. Wide color gamut (WCG) technology with high contrast ratio and transmittance has been developed from colorant design to color filter process, product reliability, and performance enhancement. In this paper, WCG technology for liquid crystal display (LCD) and organic light emitting diode (OLED) and trend of colorant, which is including color conversion material (CCM), were discussed. We hope that it will help you to understand the development flow of colorant in the display industry. [ABSTRACT FROM AUTHOR]

We review the emerging mini/micro–light‐emitting diode (LED) displays featuring high dynamic range and good sunlight readability. For mini‐LED backlit liquid crystal displays (LCDs), we quantitatively evaluate how the device contrast ratio, local dimming zone number, and local light profile affect the image quality. For the emissive mini/micro‐LED displays, the challenges of ambient contrast ratio and size‐dependent power efficiency are analyzed. Two figure‐of‐merits are proposed for optimizing the optical and electrical performances of mini/micro‐LED displays. [ABSTRACT FROM AUTHOR]

We have developed a transmissive and reflective LCD that integrates electromagnetic resonance (EMR) and capacitive touch sensors using existing in‐cell process. This development has been achieved by utilizing our hybrid‐in‐cell technology with low resistance material for the RX, which is an improvement of over 80% compared with conventional indium thin oxide (ITO) material. For EMR detection, we have slightly modified the TX layer used for capacitive touch sensing, by making a coil loop that generates a magnetic field on the panel. The direction of current on the coil can be modulated by the low‐temperature polycrystalline silicon (LTPS) circuit. Our in‐cell touch sensing has separately assigned timings for display and touch units. This time‐sharing method provides immunity from display noise and consequently better signal‐to‐noise ratio (SNR) than other out‐cell types. In parallel, we have developed a new controller that can support both EMR and capacitive sensing as a one‐chip solution, with the capability of maximizing signal levels lowering noise and detecting the frequency precisely when there is pressure on the pen tip. Our in‐cell technologies contribute not only a good SNR for EMR pen but also the added benefits for thin design, lightweight panel, compared with conventional LCD techniques. [ABSTRACT FROM AUTHOR]

Power consumption of a liquid crystal display, when it is used to display static images, can be reduced by using low frequency driving. However, when the driving frequency is decreased, the brightness of the display may change with time, a phenomenon known as image flickering. One factor responsible for the flickering issue is flexoelectric effect which is sensitive to the polarity of the applied voltage. We show that the flickering in fringe field switching (FFS) LCD can be significantly reduced by doping a liquid crystal dimer and using polymer stabilization. We demonstrated that 2 Hz driving frequency can be used to display static images. [ABSTRACT FROM AUTHOR]

With the emergence of high‐dynamic range (HDR) image and video, displaying an HDR image or video on a standard dynamic range displays with natural visual effect, clear details on local areas, and high‐contrast ratio has become an important issue. To achieve HDR, local‐dimming technique has been commonly practiced. In this paper, we investigate the problem of local dimming for LED‐backlight LC display to provide algorithm support for developing HDR displays. A novel local‐dimming algorithm is proposed to improve the contrast ratio, enhance the visual quality, and reduce the power consumption of the LCDs. The proposed algorithm mainly consists of two parts. The first part is a backlight luminance extraction method based on dynamic threshold and the maximum grayscale of an image block to improve the contrast ratio and reduce the power consumption. In the second one, a pixel compensation method based on logarithmic function is used to improve the visual quality and contrast ratio. At the same time, in order to better smooth the backlight diffusion at the edges of the backlight luminance signal to enhance the accuracy of the pixel compensation, we draw on the idea of BMA and improve it to establish the backlight diffusion model with different low‐pass‐filter templates for different types of blocks. Simulation and measured results show that the proposed algorithm outperforms the competing ones in contrast ratio, visual quality, and power‐saving ratio. We investigate the problem of local dimming for LED‐backlight LC display to provide algorithm support for developing HDR displays. The focus of this research is on the realization of the potential of local‐dimming strategy in improving the CR and visual quality of LED‐backlight LC displays. The simulation results show that the proposed algorithm outperform the competing ones in contrast ratio and visual quality, consume less energy. [ABSTRACT FROM AUTHOR]

A hydrogenated amorphous silicon (a‐Si:H) thin‐film transistor (TFT) gate driver with multioutputs (eight outputs per stage) for high reliability, 10.7‐inch automotive display has been proposed. The driver circuit is composed of one SR controller, eight driving TFTs (one stage to eight outputs) with bridging TFTs. The SR controller, which starts up the driving TFTs, could also prevent the noise of gate line for nonworking period. The bridging TFT, using width decreasing which connects between the SR controller and the driving TFT, could produce the floating state which is beneficial to couple the gate voltage, improves the driving ability of output, and reaches consistent rising time in high temperature and low temperature environment. Moreover, 8‐phase clocks with 75% overlapping and dual‐side driving scheme are also used in the circuit design to ensure enough charging time and reduce the loading of each gate line. According to lifetime test results, the proposed gate driver of 720 stages pass the extreme temperature range test (90°C and −40°C) for simulation, and operates stably over 800 hours at 90°C for measurement. Besides, this design is successfully demonstrated in a 10.7‐inch full HD (1080 × RGB×1920) TFT‐liquid‐crystal display (LCD) panel. A hydrogenated amorphous silicon (a‐Si:H) thin‐film transistor (TFT) gate driver with multioutputs (eight outputs per stage) for high reliability 10.7‐inch automotive display has been proposed. The proposed gate driver of 720 stages pass the extreme temperature range test (90°C and −40°C) for simulation and operates stably over 800 hours at 90°C for measurement. [ABSTRACT FROM AUTHOR]

We developed new light‐emitting films that emit linearly polarized light and exhibit transmittances over 90%. This film was realized through the development of a new pigment that demonstrated high orientation in film. The polarized light that emits from the film can be controlled by irradiating polarized ultraviolet light. These new films were used for the successful fabrication of a novel self‐emissive liquid crystal display that exhibited high transparency, high contrast, and good visibility. We developed new light‐emitting films that emit linearly polarized light and exhibit transmittances over 90%. This film was realized through the development of a new pigment that demonstrated high orientation in film. These new films were used for the successful fabrication of a novel self‐emissive liquid crystal display that exhibited high transparency, high contrast, and good visibility. [ABSTRACT FROM AUTHOR]

Herein, a picture control method designed to facilitate power management of large active‐matrix organic‐light‐emitting‐diode displays is proposed. In this method, Hybrid Log‐Gamma (HLG) pictures are presented simply by multiplying the upper half of the picture level by the gain corresponding to the power suppression. HLG is a standard for high‐dynamic‐range images. The controlled picture is processed by nominal luminance transformation, as well as by color conversion from red–green–blue into hue–saturation–value (HSV) imagery. Results obtained via simulations show that high‐contrast HLG pictures can be better simulated by our proposed method than by currently used conventional methods. The simulation results also demonstrate that when the picture is presented using the proposed power consumption management method, both the dark and bright regions show less deterioration. In addition, through an examination of image histograms created to elucidate detail descriptions of simulated pictures in the red–green–blue and HSV color spaces, we found that using HSV color conversion in conjunction with the proposed method mitigates chromaticity shift and that the feasibility of HSV color conversions could be quantitatively clarified by the evaluation of color differences defined by the Euclidean distance in a uniform color space. A picture level control method designed for power management of large active‐matrix organic‐light‐emitting‐diode displays is demonstrated. Bright regions of Hybrid Log‐Gamma pictures are partly suppressed to efficiently control the power consumption, and hue–saturation–value color conversion is employed to reduce chromaticity shift. Simulation results show that the proposed method can provide Hybrid Log‐Gamma pictures with less deterioration of both the dark and bright regions. [ABSTRACT FROM AUTHOR]

In this paper, we propose an autostereoscopic display with adaptive time‐division multiplexing parallax barrier. When time‐division triplexing parallax barrier is applied in place of the conventional time‐division quadruplexing parallax barrier, the image becomes brighter without destroying stereoscopy, while the viewing zone without crosstalk is narrowed. Under this trade‐off relationship, comfortable viewing conditions are secured with an adaptive display system where time‐division quadruplexing is applied in a dark environment in which crosstalk stands out and time‐division triplexing is applied in a bright environment, which requires a brighter screen to prevail against the ambient reflection. We theoretically evaluate the viewing zone without crosstalk given by different numbers of time‐division multiplexing. In this paper, we propose an autostereoscopic display with adaptive time‐division multiplexing parallax barrier. When time‐division triplexing parallax barrier is applied in place of the conventional time‐division quadruplexing parallax barrier, the image becomes brighter without destroying stereoscopy, while the viewing zone without crosstalk is narrowed. We theoretically evaluate the viewing zone without crosstalk given by different numbers of time‐division multiplexing. [ABSTRACT FROM AUTHOR]

This study aims to develop a novel in‐plane switching liquid crystal display with a fast response time, known as short‐range lurch control in‐plane switching (SLC‐IPS) mode. We found that the distance l, which is orthogonal to the liquid crystal layer thickness, affects the response properties of the liquid crystal display mode. The distance l was obtained using a simple electrode structure. The SLC‐IPS obtained by this structure exhibits a response that is approximately three times faster than that of a conventional IPS. We applied the SLC‐IPS to virtual reality head‐mounted displays and confirmed that its response properties satisfy the requirements for moving picture quality. This study aims to develop a novel in‐plane switching liquid crystal display with a fast response. We found that the distance, which is orthogonal to the liquid crystal layer thickness, affects the response properties. The novel in‐plane switching LCD exhibits a response that is approximately three times faster than that of a conventional IPS. [ABSTRACT FROM AUTHOR]

Abstract: High pixel density displays are demanded for active matrix organic light‐emitting diode displays (AMOLED) in applications such as virtual reality headsets, micro‐displays, and high‐end smartphones. Parasitic emission from non‐addressed neighboring pixels (crosstalk) is a common problem in such high pixel density AMOLED, and this crosstalk becomes more severe as the pixel density and fill ratio of the display increases. One of the causes of crosstalk is parasitic currents that travel through common organic semiconductor layers. In this paper, we model and quantify the pixel crosstalk using a 2 + 1D finite element model that is based on the conductivity of the common layer and the luminance–current–voltage curves of the subpixels as measured input parameters. We assess the effect of crosstalk on the pixel current, observed color, and luminance. The 2 + 1D model limits the number of degrees of freedom so that calculations on a standard personal computer are feasible. [ABSTRACT FROM AUTHOR]