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Electronic paper (E‐paper) relies on reflecting ambient light to achieve information display, which mimics the appearance of printed papers, but owns the features of conventional electronic displays. The outstanding characters of E‐paper including visual health, comfortable outdoor viewing and ultra‐low power consumption, attracts increasingly interests in display society. E‐paper technology has evolved slowly in the field of color reproduction and video frame rate, until the arise of electrowetting display (EWD) technology. Benefits from the innately high speed response of microfluidics, EWD enables the displaying of color video content. In this report, the basic physics of electrowetting displays, including electro‐optical response and color reproduction method will be discussed. In this presentation, recent progress on above topics, including printed conductive pillar directed oil motion control and parallax issue in CMY stacked EWD device will also be discussed.

Vehicle‐mounted displays are subject to some unique use‐cases and integration constraints that must be thoroughly considered during development to make the project successful, and the customer and end‐user pleased. This paper will touch upon some of the areas of automotive display engineering that deserves special attention. The automotive industry follows the development of MicroLED with excitement, as it holds promise of increased robustness and brightness, as well as new display types. This paper will examine some of the features that make MicroLED unique, the current state of research and its possible impact on the automotive industry.

An optimized color‐reflective LCD with high optical performances and cost‐effective structure has been proposed by association with cholesteric liquid crystal technology. By way of a color dithering algorithm, the cholesteric liquid crystal display (Ch‐LCD) can visualize a 24‐bit RGB color pixel and display over 16 million colors. Moreover, the waveform module (WF) is applied to emulate the display timing controller, which is a lowcost and more accessible way to drive the Ch‐LCD. In this paper, we demonstrated a 13.3‐inch passive matrix (PM) driven Ch‐LCD with a high resolution of 202 PPI, high reflectance of 30%, and high color gamut of 20%, which is suitable for electronic signage applications.

This paper reported on the development of a Mura‐free and high precise printing to realize high resolution QLED and OLED display panels with a G8.5 glass substrate. To realize Mura‐ free printing we developed the single‐path print line head and the new pixel volume adjustment system with a pixel volume variation of ±0.8%. And also, to realize high precise printing we developed the G8.5 table system that compensated for the drop position by changing the ejecting time of each nozzle. And verified a drop position accuracy of ±2.1μm. By combining these technologies, we achieved Mura‐free 220ppi printing on the G8.5 table.

Sustainability is not just a buzzword, but a real and increasing requirement for outdoor advertisers, media companies and network operators. This paper describes a systems approach to make incremental efficiency improvements to components of large‐format, high‐bright LCD displays. The result is a quantum leap in LCD power efficiency, creating a low‐power LCD display system that consumes only 1/3 to 1/2 the power of conventional high‐bright LCDs in the 55”‐86” range. The result is not only lower power, but also reduced heat, longer life, and little or no compromises in optical quality or cost.

Advanced neurostimulation systems require intimate interface with brain or peripheral nervous system to provide a therapeutic modulation for patients experiencing neural function loss. To achieve these, it requires stimulators with high‐channel counts and mechanical flexibility. In this invited paper, we showed a 4T1C neurostimulation pixel circuit with an active‐matrix architecture, offering the opportunity for high‐channel counts. In addition, a 4‐mask photolithographic process for highly uniform organic thin‐film transistor (OTFT) integrated system was demonstrated for mechanical flexibility, which shows a high device yield of 100% (50/50) and small device variation in threshold voltage of 0.64 V and in mobility of 4.9%. By implementing OTFTs to this novel neurostimulation architecture, we fabricated an OTFT‐based high‐channel‐count neurostimulation system, showing a high stimulator yield of 71.0% and small variation of 15.6% for the output stimulation currents among pixels.

This paper proposes a 6Gbps receiver for 8K 240Hz OLED display. In the proposed receiver, video image compression is presented to double the effective data bandwidth. In addition, it proposes dual path CTLE offset voltage calibration and CTLE adaptation with eye margin tester to implement 6Gbps receiver. The prototype IC is implemented in a 0.18μm HVCMOS process and is evaluated as an 8K 65‐inch panel.

In the evolving domain of High Dynamic Range (HDR) display metrology, the precise definition and systematic characterization of input signals is important. Using input signals that include both spatially and temporally complex image sequences is beneficial to reflect properties of real‐world content as well as to cover corner cases. One challenge with using this kind of content is to verify if it is indeed suitable for the intended purpose. This paper introduces an automated framework employing a set of statistical measures to define and characterize content, which then can serve as an important steppingstone towards programmatic image sequences and testing workflows.

The local backlight dimming (LBD) technology has attracted significant interest for liquid crystal displays. In automotive, notebook PC, and virtual reality applications, LBD should treat the trade‐off between power saving and visual quality enhancement. However, it requires the cost of the high logic complexity to consider the optimal solution at a higher resolution of the image. This paper proposes the adaptive local backlight dimming control, which can reduce the power consumption of backlight and improve the quality of the display. The proposed method analyzes an image contents with a low complexity algorithm, and it applies a local boosting to achieve a target intensity in backlight control. In performance evaluation using FPGA test system, the designed local dimming processor achieved 7.54% higher power‐saving rate with visual quality enhancement in high‐contrast region.

As a self‐emissive technology, microLED displays retain all benefits of OLEDs and should be able to improve on many aspects, but will it be enough to guaranty success? In February 2024, leading proponent Apple canceled its microLED smartwatch project. More generally, as microLED keeps getting delayed and OLED keeps improving, the value proposition of microLED is shrinking. This paper looks at how the technology could deliver stronger differentiation.

In this paper, an indium‐gallium‐zinc oxide (IGZO) based phototransistor with an electrohydrodynamic (EHD) jet printed poly (3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) absorption layer has been developed for the absorption of visible light. The PEDOT:PSS absorption layerforms a p‐n junction with IGZO, enhancing the photoresponse through selective carrier transfer of photogenerated carriers. As a result, the proposed phototransistor exhibits improved optoelectronic characteristics such as photoresponsivity of 8.40 × 102 A/W, photosensitivity of 1.12 × 107, detectivity of 8.05 × 1011 Jones under the green light (532 nm) illumination of 5 mW/mm2.

In October 2023, Meta released the Meta Quest 3 mixed reality headset, boasting a 25 PPD 4K+ Infinite Display with 2064x2208 resolution per eye — 30% more pixels and 25% higher PPD than Quest 2 and around 14% PPD boost over Quest Pro [1‐4]. Quest 3 comprises two 2.48′ 1218 PPI displays, with hybrid backplane and low‐persistence backlight to provide end‐users the superior visual quality, comfortness, and minimal latency. This paper outlines Quest 3 display architecture, immersive performances, and some key design challenges.

In this comprehensive study, we rigorously evaluated the applicability of amorphous indium gallium zinc oxide (a‐IGZO) thin films synthesized using atomic layer deposition (ALD) technology in the field of large‐area organic light‐emitting diode (OLED) TVs. The key term to display production is the distribution of device characteristics, and maintaining uniformity can improve productivity yield and product quality. The purpose of this paper is to present guidelines for early application in industry through the process variable exploration results of ALD deposition equipment. The process parameters studied are process pressure and oxygen partial pressure (PO2). We have secured a method to secure device characteristics suitable for display technology through the correlation between a‐IGZO thin film characteristics and device characteristics through corresponding parameters. Our empirical data strongly demonstrate that the threshold voltage (Vth) stabilizes near 0.0 V and consistently achieves device mobility exceeding 15 cm2/Vs. In particular, this study shows that the variability of the Vth characteristic, which is limited to a narrow range of less than ±0.1V, is greatly reduced, and the mobility dispersion is also greatly reduced to less than ±1cm2/Vs. A deeper analytical exploration revealed that the pivotal factors affecting device performance are closely related to oxygen vacancies (Vo) and their dynamic interactions with oxygen molecules. These results will improve the uniformity of device characteristics, and it is believed that the introduction of ALD technology into future display technology will demonstrate improvements in the performance and quality of display products.

In order to have a real‐world experience in the “METAVERSE”, an ultra‐high PPI device is urgently needed. In this paper, we proposed a 2117‐PPI Fast LCD Device with LTPO and Color Filter On Array (COA) technologies. We used real RGB with higher physical resolution instead of Sub Pixel Rendering (SPR) technology. We adopted the “Smart BM” technology to reduce the Screen Door Effect and the Electric Field Enhancement (EFE) technology to enhance the LC efficiency. We have developed the Planarization (PLN) Hole Filling (PHF) technology which can both increase LC efficiency and reduce the dark state light leakage. At the same time, we also used the “Smart BM” technology to improve CR.

To provide clear see‐through image quality is one of the most important performances of a transparent display, because of its see‐through capability. Purity is one of the quantitative measure can evaluate the see‐through image quality in terms of perceived blurriness. In this paper, the characteristics of purity are investigated. Experimental results indicate that the purity values have highly correlated with perceptual blurriness of see‐through images. Furthermore, the perceptual limit of purity value is also derived.

In recent years, electrophoretic display (EPD) attracts great attention for its ultra‐low power consumption, which is suitable for self‐powered applications. In this case, an energy storage system, simple as the capacitor, is essential for the self‐powered driving of EPDs. However, significance on the capacitor‐based driving of EPDs was underestimated in spite of its great practical value. This paper investigated the capacitor‐based driving of EPD for better performances of self‐powered EPDs. Based on this novel scheme, sports shoes with self‐powered EPD patterns were demonstrated as the future wearable applications.

This paper introduces an anti‐aliasing image reconstruction method in the optical coordinate domain for point‐to‐point transmission in AR/VR headset displays, employing variable downsampling ratios across different image areas to reduce transmission bandwidth and corresponding upscaling ratios at the receiver. Filter parameters for anti‐aliasing calculations at each pixel position are determined based on optical coordinates distorted by the lens, enhancing detail in areas with significant image deformation. Image quality is evaluated using MSSSIM and supported by experimental evidence.

Foveation has two methods: single image mode and dual images mode. For the former, SOC transmits the compressed image consists of different low‐resolution blocks, some of which have very large differences after up‐scaling may cause flickering risks when displayed. For the latter, SOC processes the compressed periphery and foveated images sequentially, therefor DDIC uses large GRAM to cache these bitstreams, which will also introduce huge latency. In order to solve these problems existing in two modes, this paper presents a scheme to process the image or compressed bitstreams with coding unit rearrangement.

The nanoLED, an electroluminescent device utilizing quantum dots (QDs), is expected to be a promising candidate for the next‐generation display. This paper presents a newly developed QD protection technology for cadmium‐free nanoLEDs that enables simultaneous achievement of high‐efficiency electroluminescence (EL) and long lifetime. The device which was prototyped by applying ZnSeTe blue QDs to an emissive layer demonstrated a maximum external quantum efficiency (EQE) of 21.0% and a luminance half‐lifetime (LT50) of 128,000 hours at 100 nits. These results indicate that cadmium‐free nanoLEDs can meet the requirements for display application in terms of both EL efficiency and reliability.

This paper covers the overview of liquid crystal lenses for 3D displays and our latest technology that reduces the switching time of the LC lens. First, a binocular near‐eye DFD display system utilizing binary focus lenses including a liquid crystal layer is described. Then, we review a two‐way multiview 2D/3D display that can achieve 3D images in both landscape and portrait. Finally, for the fast switching time of LC lenses, we report a novel driving method by applying a vertical electric field that achieved 25 times faster turn‐off time than the conventional method.

Fast‐switching high‐efficiency liquid crystal grating is a key component in holographic true‐3D display systems. In this paper, we present our research and development of a 10.7” liquid crystal grating with 2‐3 millisecond switching time, close‐to‐ideal deflection efficiency, and >100 polarization contrast. The high performance is achieved by optimizing the design and process of the liquid crystal grating panel as well as the optical module stack. Several key design principles are analyzed and verified. Based on the developed liquid crystal grating, a 10.4” full‐color naked‐eye holographic 3D display prototype is successfully realized.

Recently deuteration has become a key technology for enhancing lifetime of OLED materials without affecting other performance parameters like efficiency and voltage. Over the past years, we intensively investigated the impact of the deuteration degree and pattern on the device performance. The focus of our investigation was triplet matrix materials (TMMs) in the emissive layer and the electron‐blocking layer (EBL). In this paper, we will discuss various aspects of the deuteration of OLED materials: from driving further performance improvements to scale‐up processes.

Strain sensors which are embeded in AMOLED are introduced and studied in this paper. High accuray strain sensing are achieved, resolution of the sensors are about 0.05%. By combing the strain sensors in the panel, mechanical behaviors can be monitored and studied in real time. The snesors are used to conduct the foldable AMOLED mechanical and reliability study. Dynamic and static strains and related mechanism are introduced and discussed. Finite element simulation models considering the mechanical properties of materials including hyperelasticity, viscoelasticity and creep are established. Finally, the strain sensors and finite element anlysis are combined to study the mechanical response of AMOLED under dynamic folding, static folding, and different temperature and humidity environments.

This paper presents an OLED display driver IC with a high‐ gain fast‐slew(HGFS) and an on‐the‐fly self‐repair(OFSR) circuits for a spatial resolution of WQHD and a frame rate of 120Hz To reduce a settling time of a source driver as resolution andframe rate are increase, the proposed HGFS circuit increases a slewing current of unity‐gain amplifier of source driver when an input voltage is largely changed. In addition, to improve image quality by display line defect, the OFSR circuit is operated by replacing a failure channel to a spared dummy channel. The OLED display driver IC was fabricated using a 28nm high‐ voltage process with 8V/20V transistors which has source drivers of 2,880‐channels for WQHD display. The measurement results show the horizontal line time of 2.7ps with slew rate of 7.675V/ps, which support WQHD resolution and 120Hz frame rate. Also, the demonstrated image shows that a display vertical line defect is disappeared by using OFSR.

The recent main topics in ISO/TC159/SC 4/WG 2 and /WG12, which are in charge of display ergonomics in the International Organization for Standardization (ISO), is ergonomics of head‐mounted displays (HMDs) realizing XR or Cross‐Reality, which has attracted attention in recent years. The paper overviews the major issues related to visual comfortability and Image Safety using HMDs, and reports on the key points for standardization to reduce VR sickness and to maintain comfortable viewing of 3D images.

Due to their very high resolution and high level of technological maturity, OLED microdisplays are an ideal image generator for VR, AR and MR applications in near‐to‐eye optics. However, due to the silicon‐based backplane, these microdisplays have always been non‐transparent, requiring a complex optical system for integration into an optic. This has a significant impact on the weight, size and overall optical efficiency of the system. In this paper, a novel technology for the realization of semi‐transparent OLED‐on‐silicon microdisplays is presented, which enables completely new optical concepts for near‐to‐eye optics.

Stretchable displays based on conventional materials exhibit a trade‐off relationship between the pixel density and the stretchability. In this paper, we have demonstrated overcoming the technological limitations of stretchable displays through the optimization of serpentine‐shaped bridge design and the application of stretchable metal electrodes. The application of stretchable electrodes has increased stretchability by over 30% without compromising pixel density.

The PC display market has evolved rapidly in recent years, with new technologies and capabilities like high dynamic range (HDR), motion blur reduction and ultra‐high variable refresh rates being introduced at a rapid rate. However, when it comes to choosing a display, consumers are often at a disadvantage. How can they better understand the capabilities of each display, and trust the specs provided by the manufacturer? For display OEMs, having consistent, measurable display performance parameters around which to qualify and promote their products is also beneficial to product development and commercialization. For the past six years, the Video Electronics Standards Association (VESA) has released multiple front‐of‐screen performance standards to help consumers and OEMs meet these needs. This paper will review the compliance test specifications for several of these standards, including the newest update to VESA's HDR standard, DisplayHDR v1.2, which will be launched in the first half of 2024.

In this paper, we present the small area and high reliable gate driver in panels using a‐IGZO TFTs for large OLED displays. The proposed gate driver circuit has a small area structure with multiple output buffers connected to one shift register circuit. To lower the voltage stress of the pull‐down TFTs, which have the highest voltage stress among the TFTs of the gate driver, the initial voltage of those TFTs is set to low and increases according to the threshold voltage shift of TFTs during operation. It could be implemented by sensing the degradation of the TFTs using the programmable DC driving method. With these technologies, we were able to reduce the gate driver design area by 40% and improve the reliability by 30% despite reducing the circuit area. We successfully developed OLED TVs from 42 inches to 97 inches using the proposed gate driver.

The Chiral Polymer Stabilized Vertical Alignment (C‐PS‐VA) technology enables up to 10% increase in transmittance leading to potentially lower power consumption of final devices and energy saving compared to conventional Polymer Stabilized Vertical Alignment (PS‐VA) technology. Self‐Aligned Vertical Alignment (SA‐VA) enables the simplification of the process to achieve energy saving by eliminating high‐temperature baking. This paper summarizes the recent developments of liquid crystal mixtures for C‐PS‐VA & SA‐VA technologies in terms of performance and reliability.

In this paper the photolithgraphic patterning approaches of quantum dots in electroluminescent devices and demoes were summerized. Photolithograpy process meets the requirements for QLED mass production, including high pixel density, large‐area process and low cost. We summerized three approaches of quantum dot photolithographic procrsses, including direct photolithography, photolithography with lift‐off process and sacrificial layer assisted patterning (SLAP).

In this paper, we demonstrated the front NFC card swipe and touch display in TDDI LCD through the technologies shown later. New NFC sampling and noise reduction algorithm was used to reduce the generation of the Ghost Position and Touch Failure. The Time Division Multiplexing was applied to optimize the noise interference when NFC works. Meanwhile, we integrated the NFC antenna in the TDDI LCD, and also added new display signal filter circuit and VCOM driver signal. In the NFC in‐cell demo, front NFC swiping distance of 50mm is achieved.

Binocular 3D display systems, including virtual, augmented and mixed reality (collectively referred to as XR) devices support stereoscopic depth perception by presenting dichoptic views separately to the two eyes rendered according to their vantage points. A common human factors issue is a mismatch between the observer's physical interpupillary distance (IPD) and 1) the separation between the device optics and 2) the rendered/captured content. This paper provides a theoretical review of the importance and consequences for user experience of accurately estimating IPD and incorporating it into HMD adjustments, calibration and rendering.

This paper presents the development of liquid crystal on silicon (LCOS) technology aimed at enhancing the image quality and reliability of projectors. Additionally, we introduce an 8K LCOS panel with a pixel pitch of 2.6 μm. Furthermore, we discuss the application prospects of the developed phase‐only spatial light modulator.

The development of OLED materials by molecular design is important for high performance organic light emitting diode because tailoring the molecular structures can dramatically tune the properties such as efficiency, color, stability of device. Near‐infrared organic light‐emitting diodes (NIR OLEDs) with heavy metals or TADF materials are regularly reported due to the advantages of their various applications in healthcare services, veil authentication, and night vision displays. In this paper, we are summarized the collection of innovative organic near‐infrared (NIR) emitters which is crucial factor to design specific NIR emitter for NIR OLEDs

A number of technologies must be highly integrated to deliver immersive XR experiences to users. These technologies are not only for XR hardware but also for content creation and distribution. In this paper, the author introduces an XR workflow and reviews some key technologies. The challenges and perspectives of XR technologies are also discussed.

With the continuous evolution of technology, XR products are expected to witness significant breakthroughs and advancements in these aspects, ultimately enhancing the overall user experience. However, careful consideration and optimization of these characteristics based on the intended purpose and usage scenarios of the product remain an area of ongoing research. The primary goal of this paper is to provide a comprehensive reference framework for researchers and product developers to facilitate further research and development in XR technology. By analyzing and discussing the existing literature, this review aims to synthesize the current understanding and state‐of‐the‐art progress in XR technology, serving as a valuable resource for researchers and developers seeking to innovate in this rapidly growing field.

One of the micro‐LED direct view display major challenges is to find ways of drastically dropping the cost, for instance, by reducing the micro‐LED size, simplifying the assembly process and improving the assembly yield. In this paper, we present Aledia's GaN‐on‐Si nanowire (NW) LED technology made on standard 8 “Si wafers, scalable to 12” wafers. We will present two components using our NW technology and their use case for the manufacturing of micro‐LED direct view fine pitch display: NWs RGB three color chips obtained using quantum dot (QD) color conversion at chip level. The RGB chips can then be transferred on PCB or glass or TFT substrates for panel manufacturing.The integration within the same chip of a three color RGB chip together with its CMOS driving electronics. Those chips allow to obtain an active‐matrix architecture on any passive backplane without the use of TFT.

In this paper, we propose a method of generating the elemental image array (EIA) for the integral imaging (InIm) based light field display (LFD). Firstly, we reveal the intrinsic voxel spatial distributions of the InIm‐based LFD and analyze how the voxel space affects the display performances such as spatial resolution, depth of field, and smoothness of parallax. Then, we present an algorithm to generate an EIA from a pair of RGB and depth (RGBD) images and an optimally selected voxel space. In the experiments, we tested the display performances of the voxels on different depth planes and obtained results consistent with the theoretical analyses. We also experimented with a computer 3D model and a real‐world scene on two InIm‐based LFD prototypes working in different modes, one in real mode and the other in virtual mode, and obtained favorable 3D display effects. The proposed method simplifies the light field data acquisition and image synthesis process, and supports handling both the virtual and the real‐world 3D scenes. We expect the proposed system to help the practical application of the InIm‐based LFD technology.

Acrylic photoresist could be applied as a functional layer for OLED display, and it is required to be fabricated mainly on the hybrid substrate of metal and inorganic silicide substrate or the polymer substrate. Through simulation, this paper concludes that moderately increasing the silane coupling agent content and moderate crosslinking degree of the material system could contribute to improving the adhesion force at the interface between acrylic photoresist and substrate, thereby avoiding peeling. Four acrylic photoresists named OC1‐4 with different formula are introduced, their adhesion force and peeling performances on different substrates are researched. The experimental results are consistent with that of simulation. Among them, OC1&4 with high content of silane coupling agent did not exhibit peeling on the hybrid substrate and polymer substrate, and their adhesion forces are large enough, making them suitable as functional layers for OLED display.

This paper presented intelligent display technologies integrated in the 55‐inch 4K LCD cell based on a‐Si process. Adaptive adjustment of backlight brightness and optimization of LC response time were achieved utilizing the ALS and TS integration. By using the novel GOA architecture and TCON IC, dynamic local refresh at any position and with different refresh rate at different area on panel were achieved. The power consumption of GOA and data drivers can be reduced by up to 50% respectively. This technology provides hardware foundation for the realization of AI intelligent display.

Because it can make “snail house” realize the dream of large screen, ultra‐short throw projection display has developed rapidly in the application of indoor display. However, due to its unique characteristics of short‐distance projection, using illuminance meter to test and evaluate the uniformity of projection will cause large errors. In this paper, it is recommended to use imaging luminance meter instead of illuminance meter to evaluate the optical characteristics of ultra‐short throw projection display by referring to the test methods of traditional indoor displays, and the applicability of this method is proved by measured data.

iBeam Materials is developing a revolutionary new technology to fabricate large‐area inexpensive sheets of GaN‐based LEDs and devices directly on large‐area metal foils. This new technology is based on using ion‐beam crystal alignment to fabricate templates for epitaxial GaN films on flexible metal foil, that are lattice‐matched, as well as thermally highly conductive and thermally matched to GaN. The ion beam assisted deposition (IBAD) texturing process is used to prepare biaxially aligned films as templates for GaN epitaxy. Epitaxial GaN films have been grown on these engineered flexible metal substrates. We have achieved GaN films of several microns in thickness on polycrystalline metal foils that have typical threading dislocation densities of 4 – 8 x 108/cm2. We then used these epitaxial GaN films on IBAD/polycrystalline metal foil as templates to deposit epitaxial multi‐quantum well light emitting diode (LED) InGaN structures. InGaN LED devices were successfully fabricated and patterned into MicroLED arrays on metal foil. We observe photoluminescence from these LED structures with 70% of the intensity compared to LEDs fabricated on sapphire. We discuss how these LED devices could be manufactured using a roll‐to‐roll process and cost reductions that result from this. Large‐area LED sheets can then be used to monolithically integrate MicroLEDs into paper‐thin and flexible displays.

In this paper, we summarize the various opportunities and challenges in Photopolymer based VHG optical waveguides. By comparing with SRG, we analyzed the advantages of VHG in rainbow effect and eye glow in principle. Besides, we list the challenges faced by VHGs such as grating vector testing, shrinkage effect, light leakage, and material absorption, and give some of the solutions as well as possible solution ideas. The solution of the above challenges will provide new theoretical and technical support for the practicalization of VHG optical waveguides.

Surface Dial is a mass production PC accessory implementing a tangible interface for on‐and off‐screen interactions. It enables a dual‐handed interaction model in content creation tasks like drawing, video editing, presentation and data visualization. We delve into design considerations, including development of a capacitive approach for on‐screen detection and tracking.

Reflective LCDs have a great advantage of low power consumption, but the brightness is not consistently sufficient because ambient light is used as a light source. To increase light efficiency, we combined reflective LCDs and the Pancharatnam‐Berry deflector (PBD), a diffractive optical element that controls the propagation of incident light. We confirmed that on‐axis brightness is increased by 2.2 times against the incident collimated light from a polar angle of 30° when compared to a reflective LCD without PBD.

Cholesteric liquid crystal (ChLC) is a reflective display technology that utilizes ambient light sources to display images, eliminating the need for a backlight. With its bistable characteristics, ChLC displays only require voltage supply during screen updates, resulting in significant energy savings. To cater to various application scenarios, we have developed ChLC reflective displays with different functionalities and sizes. The 7.9‐ inch passive matrix ChLC reflective display offers features such as full‐color capability, wide viewing angles, and fast refreshing rate, making it suitable for electronic book applications. The 24.5‐ inch and 13.3‐inch displays are respectively the largest passive matrix ChLC reflective display and active matrix ChLC reflective display in the world. They incorporate wide temperature range materials and high contrast ratio driving methods, making them highly suitable for outdoor public information display applications.

The most effective way to improve display visibility in ambient light is to suppress the reflectance of the display. After conducting a thorough analysis of the factors contributing to unwanted reflection, specific layers were identified that required improvement. Subsequently, these elements were carefully optimized, resulting in a significant reduction of internal reflection to 0.53% for our 12.3” FFS‐mode prototype, compared to 1.12% in conventional LCDs. This improvement was achieved without the use of circular polarizers and has been demonstrated to provide excellent visibility in bright ambient conditions while allowing for reduced backlight brightness and lower power consumption.

We developed a flexible imager comprising low‐temperature polycrystalline silicon thin‐film transistors and organic photodiodes. The developed flexible imager has high‐resolution and high‐speed readout characteristics. Owing to these characteristics, pulse wave signals can be measured, and the images of fingerprints and veins can be obtained. Furthermore, we developed three‐axis tactile pressure sensors by integrating flexible optical components. The sensors can detect both normal and tangential pressures.

A low‐temperature technology for fabricating thin‐film transistors (TFTs) is essential for the realization of electronic systems on flexible substrates. Presently reviewed are improved techniques for forming the source/drain regions and reducing the population of channel defects in a metal‐oxide TFT. These have been applied to the construction of different TFT structures, including ones with bottom gate, top gate, and dual gates. The utility of the improved 300‐°C technology has been demonstrated by the realization of a variety of electronic systems, such as a gate‐driver on array for active‐matrix displays, an analog front‐end for acquiring biopotential signals, and an artificial neural network for neuromorphic computing.