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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 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]

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]

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]

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: This paper proposes an optimal design method that minimizes the common voltage (VCOM) distortion for large‐sized and high‐resolution liquid crystal displays (LCDs). Three design methods are examined using different architectures of the panel and circuit to compensate for the VCOM distortion. The proposed design method adopts a panel architecture that compensates for the VCOM distortion simultaneously at the top and bottom of the panel using a dual compensation circuit. It is implemented using a 27‐in. quad high‐definition LCD, and its VCOM distortion is further minimized by optimizing the compensation ratio of the dual compensation circuit. In addition, the minimized VCOM distortion is evaluated by measuring the horizontal crosstalk of the implemented panel according to the decrease in the charging time of the subpixel. As the charging time decreases from 11.6 to 7.8 μs, the measured crosstalk level varies from 0.10% to 1.06%, respectively, meeting the goal of less than 2%. Therefore, the proposed design method is suitable for large‐sized and high‐resolution LCDs requiring low VCOM distortion. [ABSTRACT FROM AUTHOR]

In this paper, we propose an in-cell active touch circuit using the concept of floating common electrode for large size in-plane-switching liquid crystal displays. Compared with the conventional passive in-cell touch circuit, the proposed method can greatly reduce the readout channel numbers by sharing the sensing bus for one column. Because the touch signal is amplified in the pixel, the touch panel can be easily scaled up in size. Simulation results show that the difference between touch and no-touch signals can be as large as 10 μA even with threshold voltage shift of ±1 V. The possible issues of the proposed method are experimentally verified. [ABSTRACT FROM AUTHOR]

This paper proposes a design method to reduce the flicker of liquid crystal display panels based on indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs). The proposed design method employs a human factor model to convert the flicker measured at low frame frequency ( FFRAME) to a modification value of the measured flicker ( MVMF) having a frequency sensitivity of flicker, which can distinguish between no blinking and weak blinking. To investigate the causes and characteristics of flicker, the frequency component and increase factor of flicker are analyzed using the checkerboard and solid images. The increase factor in flicker is examined using IGZO TFTs with different antenna ratios ( ARs) that cause the variation in threshold voltage of IGZO TFT. To verify the proposed design method, two test panels are implemented with asymmetric and symmetric ARs. The MVMFs of the 15 Hz component at a low FFRAME of 30 Hz show that the solid image with a symmetric AR has an MVMF of −62.9 dB, which is improved by 24.3 dB compared to that with an asymmetric AR. Therefore, the proposed method is applicable for a flicker-free liquid crystal display panels at a low FFRAME. [ABSTRACT FROM AUTHOR]

We fabricated a prototype of a 434-ppi 5.9-in reflective liquid crystal display for use as an e-book reader. With high-level optical characteristics with a reflectance of 28.7% and an NTSC ratio of 37%, we achieved eye-friendly reflective liquid crystal display. [ABSTRACT FROM AUTHOR]

A side sealing structure including, outside a sealant, AlOx deposited using an atomic layer deposition apparatus was employed for a low-frequency driving liquid crystal display (LCD) with a bezel width of 0.7 mm. This side-sealing structure can effectively prevent the entry of external moisture. Prevention of decrease in voltage-holding ratio was confirmed with a test cell having this structure. A narrow-bezel LCD with c-axis-aligned a-b-plane-anchored crystal In-Ga-Zn Oxide backplane can have long-term high reliability as a low-frequency driving LCD. [ABSTRACT FROM AUTHOR]

We fabricated two types of 6.05-in. active matrix reflective liquid crystal displays (LCD) using a c-axis-aligned crystalline oxide semiconductor (CAAC-OS) for the driver circuit and field-effect transistors in pixels: one is of the high-reflectance type, and the other is of the wide-gamut type. Because of the small off-state current of the CAAC-OS and the improved liquid crystal material, low-frequency driving at 1/60 fps or lower was achieved without memory in a pixel. Consequently, the still image display does not require data writing, except in turning pages; thus, it is flicker-free in still image display. We also examined the page-turning operation for less eye strain. The study shows that a reflective color LCD using a CAAC-OS results in eye-friendly still image display without flicker similar to an electrophoretic display (EPD); however, it is capable of moving image display, color display, and eye-friendly page-turning operation, which are difficult to achieve with an EPD. [ABSTRACT FROM AUTHOR]

We design a blue phase dual-view liquid crystal display (BP DVLCD) based on a directional backlight system. Combining the patterned electrodes with the directional backlight system, the cross-talk ratio is reduced to only 1.17%. Moreover, the resolution and brightness will be tripled by using field-sequential color display. In the preferred viewing area, the BP DVLCD has a high contrast ratio of ~1700:1. [ABSTRACT FROM AUTHOR]

A reference pattern method based on synchronous measurement for evaluating the response time of liquid crystal display was proposed to overcome the shortcomings of the unsmooth response curve induced by the backlight modulation. The feasibility of the method is verified by measurement using a high speed charge-coupled device camera. The measured gray-to-gray response time results are compared with those obtained from standard measurement approach. The results indicate that the proposed method improves the accuracy and repeatability of the response time measurement. [ABSTRACT FROM AUTHOR]

In order to reduce eye strain, a driving method for reducing flickers of liquid crystal display (LCD) is devised. For this driving, an oxide semiconductor (OS) is used in a backplane, liquid crystal and alignment layer materials are optimized, and a fringe field switching (FFS) mode with a structurally formed storage capacitor is used. This work reveals that suitable usages of positive and negative liquid crystals differ from each other according to their characteristics. This work also describes an OS-LCD with a touch sensor we fabricated for mobile devices, which proves the possibility of reducing-eye-strain technology (REST) with reduced flickers. [ABSTRACT FROM AUTHOR]