Fast and Stable Zinc Anode‑Based Electrochromic Displays Enabled by Bimetallically Doped Vanadate and Aqueous Zn^(2+)/Na^(+)Hybrid Electrolytes

Vanadates are a class of the most promising electrochromic materials for displays as their multicolor characteristics.However,the slow switching times and vanadate dissolution issues of recently reported vanadates significantly hinder their diverse practical applications.Herein,novel strategies are developed to design electrochemically stable vanadates having rapid switching times.We show that the interlayer spacing is greatly broadened by introducing sodium and lanthanum ions into V_(3)O_(8)interlayers,which facilitates the transportation of cations and enhances the electrochemical kinetics.In addition,a hybrid Zn^(2+)/Na^(+)electrolyte is designed to inhibit vanadate dissolution while significantly accelerating electrochemical kinetics.As a result,our electrochromic displays yield the most rapid switching times in comparison with any reported Zn-vanadate electrochromic displays.It is envisioned that stable vanadate-based electrochromic displays having video speed switching are appearing on the near horizon.

Non-volatile dynamically switchable color display via chalcogenide stepwise cavity resonators

High-resolution multi-color printing relies upon pixelated optical nanostructures,which is crucial to promote color display by producing nonbleaching colors,yet requires simplicity in fabrication and dynamic switching.Antimony trisulfide(Sb_(2)S_(3))is a newly rising chalcogenide material that possesses prompt and significant transition of its optical characteristics in the visible region between amorphous and crystalline phases,which holds the key to color-varying devices.Herein,we proposed a dynamically switchable color printing method using Sb_(2)S_(3)-based stepwise pixelated Fabry-Pérot(FP)cavities with various cavity lengths.The device was fabricated by employing a direct laser patterning that is a less timeconsuming,more approachable,and low-cost technique.As switching the state of Sb_(2)S_(3) between amorphous and crystalline,the multi-color of stepwise pixelated FP cavities can be actively changed.The color variation is due to the profound change in the refractive index of Sb_(2)S_(3) over the visible spectrum during its phase transition.Moreover,we directly fabricated sub-50 nm nano-grating on ultrathin Sb_(2)S_(3) laminate via microsphere 800-nm femtosecond laser irradiation in far field.The minimum feature size can be further decreased down to~45 nm(λ/17)by varying the thickness of Sb_(2)S_(3) film.Ultrafast switchable Sb_(2)S_(3) photonic devices can take one step toward the next generation of inkless erasable papers or displays and enable information encryption,camouflaging surfaces,anticounterfeiting,etc.Importantly,our work explores the prospects of rapid and rewritable fabrication of periodic structures with nano-scale resolution and can serve as a guideline for further development of chalcogenide-based photonics components.

Laser patterning of large-scale perovskite single-crystal-based arrays for single-mode laser displays

Lead halide perovskites have attracted considerable attention as potential candidates for high-performance nano/microlasers,owing to their outstanding optical properties.However,the further development of perovskite microlaser arrays(especially based on polycrystalline thin films)produced by the conventional processing techniques is hindered by the chemical instability and surface roughness of the perovskite structures.Herein,we demonstrate a laser patterning of large-scale,highly crystalline perovskite single-crystal films to fabricate reproducible perovskite single-crystal-based microlaser arrays.Perovskite thin films were directly ablated by femtosecond-laser in multiple low-power cycles at a minimum machining line width of approximately 300 nm to realize high-precision,chemically clean,and repeatable fabrication of microdisk arrays.The surface impurities generated during the process can be washed away to avoid external optical loss due to the robustness of the single-crystal film.Moreover,the high-quality,large-sized perovskite single-crystal films can significantly improve the quality of microcavities,thereby realizing a perovskite microdisk laser with narrow linewidth(0.09 nm)and low threshold(5.1µJ/cm2).Benefiting from the novel laser patterning method and the large-sized perovskite single-crystal films,a high power and high color purity laser display with single-mode microlasers as pixels was successfully fabricated.Thus,this study may offer a potential platform for mass-scale and reproducible fabrication of microlaser arrays,and further facilitate the development of highly integrated applications based on perovskite materials.

Atomic layer deposition in advanced display technologies:from photoluminescence to encapsulation

Driven by the growing demand for next-generation displays,the development of advanced luminescent materials with exceptional photoelectric properties is rapidly accelerating,with such materials including quantum dots and phosphors,etc.Nevertheless,the primary challenge preventing the practical application of these luminescent materials lies in meeting the required durability standards.Atomic layer deposition(ALD)has,therefore,been employed to stabilize luminescent materials,and as a result,flexible display devices have been fabricated through material modification,surface and interface engineering,encapsulation,cross-scale manufacturing,and simulations.In addition,the appropriate equipment has been developed for both spatial ALD and fluidized ALD to satisfy the low-cost,high-efficiency,and high-reliability manufacturing requirements.This strategic approach establishes the groundwork for the development of ultra-stable luminescent materials,highly efficient light-emitting diodes(LEDs),and thin-film packaging.Ultimately,this significantly enhances their potential applicability in LED illumination and backlighted displays,marking a notable advancement in the display industry.

Dynamic interactive bitwise meta-holography with ultra-high computational and display frame rates

Interactive holography offers unmatched levels of immersion and user engagement in the field of future display.Despite of the substantial progress has been made in dynamic meta-holography,the realization of real-time,highly smooth interactive holography remains a significant challenge due to the computational and display frame rate limitations.In this study,we introduced a dynamic interactive bitwise meta-holography with ultra-high computational and display frame rates.To our knowledge,this is the first reported practical dynamic interactive metasurface holographic system.We spa-tially divided the metasurface device into multiple distinct channels,each projecting a reconstructed sub-pattern.The switching states of these channels were mapped to bitwise operations on a set of bit values,which avoids complex holo-gram computations,enabling an ultra-high computational frame rate.Our approach achieves a computational frame rate of 800 kHz and a display frame rate of 23 kHz on a low-power Raspberry Pi computational platform.According to this methodology,we demonstrated an interactive dynamic holographic Tetris game system that allows interactive gameplay,color display,and on-the-fly hologram creation.Our technology presents an inspiration for advanced dynamic meta-holography,which is promising for a broad range of applications including advanced human-computer interaction,real-time 3D visualization,and next-generation virtual and augmented reality systems.

Flexible perovskite light-emitting diodes for display applications and beyond

The flexible perovskite light-emitting diodes(FPeLEDs),which can be expediently integrated to portable and wearable devices,have shown great potential in various applications.The FPeLEDs inherit the unique optical properties of metal halide perovskites,such as tunable bandgap,narrow emission linewidth,high photoluminescence quantum yield,and particularly,the soft nature of lattice.At present,substantial efforts have been made for FPeLEDs with encouraging external quantum efficiency(EQE)of 24.5%.Herein,we summarize the recent progress in FPeLEDs,focusing on the strategy developed for perovskite emission layers and flexible electrodes to facilitate the optoelectrical and mechanical performance.In addition,we present relevant applications of FPeLEDs in displays and beyond.Finally,perspective toward the future development and applications of flexible PeLEDs are also discussed.

Thermochromic Silks for Temperature Management and Dynamic Textile Displays

Silks have various advantages compared with synthetic polymer fibers,such as sustainability,mechanical properties,luster,as well as air and humidity permeability.However,the functionalization of silks has not yet been fully developed.Functionalization techniques that retain or even improve the sustainability of silk production are required.To this end,a low-cost,effective,and scalable strategy to produce TCSs by integrating yarn-spinning and continuous dip coating technique is developed herein.TCSs with extremely long length(>10 km),high mechanical performance(strength of 443.1 MPa,toughness of 56.0 MJ m−3,comparable with natural cocoon silk),and good interfacial bonding were developed.TCSs can be automatically woven into arbitrary fabrics,which feature super-hydrophobicity as well as rapid and programmable thermochromic responses with good cyclic performance:the response speed reached to one second and remained stable after hundreds of tests.Finally,applications of TCS fabrics in temperature management and dynamic textile displays are demonstrated,confirming their application potential in smart textiles,wearable devices,flexible displays,and human–machine interfaces.Moreover,combination of the fabrication and the demonstrated applications is expected to bridge the gap between lab research and industry and accelerate the commercialization of TCSs.

Symptomatic accommodative and binocular dysfunctions from the use of flat-panel displays

AIM： To determine the presence of symptomatic accommodative and non-strabismic binocular dysfunctions （A.sBD） in a non-presbyopic population of video display unit （VDU） users with flat-panel displays. METHODS： One hundred and one VDU users, aged between 20 to 34y, initially participated in the study. This study excluded contact-lens wearers and subjects who had undergone refractive surgery or had any systemic or ocular disease. First, subjects were asked about the type and nature of eye symptoms they experienced during VDU use. Then, a thorough eye examination excluded those subjects with a significant uncorrected refractive error or other problem, such as ocular motility disorders, vertical deviation, strabismus and eye diseases. Finally, the remaining participants underwent an exhaustive assessment of their accommodative and binocular vision status. RESULTS： Eighty-nine VDU users （46 females and 43 males） were included in this study. They used flat-panel displays for an average of 5±1.9h a day. Twenty subjects presented A.sBD （22.5%）. Convergence excess was the most frequent non-strabismic binocular dysfunction （9 subjects）, followed by fusional vergence dysfunction （3 subjects） and convergence insufficiency （2 subjects）. Within the accommodative dysfunctions, accommodative excess was the most common （4 subjects）, followed by accommodative insufficiency （2 subjects）. Moderate to severe eye symptoms were found in 13 subjects with ANSBD. CONCLUSION： Significant eye symptoms in VDU users with accommodative and/or non-strabismic binocular dysfunctions often occur and should not be underestimated; therefore, an appropriate evaluation of accommodative and binocular vision status is more important for this population,

Prospects and challenges in augmented reality displays

Augmented reality(AR)displays are attracting significant attention and efforts.In this paper,we review the adopted device configurations of see-through displays,summarize the current development status and highlight future challenges in micro-displays.A brief introduction to optical gratings is presented to help understand the challenging design of grating-based waveguide for AR displays.Finally,we discuss the most recent progress in diffraction grating and its implications.

Time-sequential color code division multiplexing holographic display with metasurface

Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface holography can only realize static manipulation.In this study,we propose and demonstrate a multiplexing metasurface technique combined with multiwavelength code-division multiplexing(CDM)to realize dynamic manipulation.Multicolor code references are utilized to record information within a single metasurface and increase the information capacity and security for anticracks.A total of 48 monochrome images consisting of pure color characters and multilevel color video frames were reconstructed in dual polarization channels of the birefringent metasurface to exhibit high information density,and a video was displayed via sequential illumination of the corresponding code patterns to verify the ability of dynamic manipulation.Our approach demonstrates significant application potential in optical data storage,optical encryption,multiwavelengthversatile diffractive optical elements,and stimulated emission depletion microscopy.

Flexible Large-Area Graphene Films of 50-600 nm Thickness with High Carrier Mobility

Bulk graphene nanofilms feature fast electronic and phonon transport in combination with strong light-matter interaction and thus have great potential for versatile applications,spanning from photonic,electronic,and optoelectronic devices to charge-stripping and electromagnetic shielding,etc.However,large-area flexible close-stacked graphene nanofilms with a wide thickness range have yet to be reported.Here,we report a polyacrylonitrile-assisted’substrate replacement’strategy to fabricate large-area free-standing graphene oxide/polyacrylonitrile nanofilms(lateral size~20 cm).Linear polyacrylonitrile chains-derived nanochannels promote the escape of gases and enable macro-assembled graphene nanofilms(nMAGs)of 50-600 nm thickness following heat treatment at 3,000℃.The uniform nMAGs exhibit 802-1,540 cm^(2)V-1s-1carrier mobility,4.3-4.7 ps carrier lifetime,and>1,581 W m^(-1)K^(-1)thermal conductivity(n MAG-assembled 10μm-thick films,mMAGs).nMAGs are highly flexible and show no structure damage even after 1.0×10^(5)cycles of folding-unfolding.Furthermore,n MAGs broaden the detection region of graphene/silicon heterojunction from near-infrared to mid-infrared and demonstrate higher absolute electromagnetic interference(EMI)shielding effectiveness than state-of-the-art EMI materials of the same thickness.These results are expected to lead to the broad applications of such bulk nanofilms,especially as micro/nanoelectronic and optoelectronic platforms.

Metasurfaces for near-eye display applications

Virtual reality(VR)and augmented reality(AR)are revolutionizing our lives.Near-eye displays are crucial technologies for VR and AR.Despite the rapid advances in near-eye display technologies,there are still challenges such as large field of view,high resolution,high image quality,natural free 3D effect,and compact form factor.Great efforts have been devoted to striking a balance between visual performance and device compactness.While traditional optics are nearing their limitations in addressing these challenges,ultra-thin metasurface optics,with their high light-modulating capabilities,may present a promising solution.In this review,we first introduce VR and AR near-eye displays,and then briefly explain the working principles of light-modulating metasurfaces,review recent developments in metasurface devices geared toward near-eye display applications,delved into several advanced natural 3D near-eye display technologies based on metasurfaces,and finally discuss about the remaining challenges and future perspectives associated with metasurfaces for near-eye display applications.

Humanoid Intelligent Display Platform for Audiovisual Interaction and Sound Identification

This study proposes a rational strategy for the design,fabrication and system integration of the humanoid intelligent display platform(HIDP)to meet the requirements of highly humanized mechanical properties and intelligence for human-machine interfaces.The platform’s sandwich structure comprises a middle lightemitting layer and surface electrodes,which consists of silicon elastomer embedded with phosphor and silk fibroin ionoelastomer,respectively.Both materials are highly stretchable and resilient,endowing the HIDP with skin-like mechanical properties and applicability in various extreme environments and complex mechanical stimulations.Furthermore,by establishing the numerical correlation between the amplitude change of animal sounds and the brightness variation,the HIDP realizes audiovisual interaction and successful identification of animal species with the aid of Internet of Things(IoT)and machine learning techniques.The accuracy of species identification reaches about 100%for 200 rounds of random testing.Additionally,the HIDP can recognize animal species and their corresponding frequencies by analyzing sound characteristics,displaying real-time results with an accuracy of approximately 99%and 93%,respectively.In sum,this study offers a rational route to designing intelligent display devices for audiovisual interaction,which can expedite the application of smart display devices in human-machine interaction,soft robotics,wearable sound-vision system and medical devices for hearing-impaired patients.

DisplaySearch：宏基收购后的挣扎

Display Search新一季度笔记本市场的销售量及前景预测的研究报告指出：宏基在收购了Gateway和Packard Bell后似乎进行着一番挣扎。

NOVEL POLYMER WIDE VIEWING ANGLE COMPENSATION FILMS FOR LIQUID CRYSTAL DISPLAYS(LCDS)

We report on generating uniaxial negative birefringent compensation films, made of specifically designedpolyimides. These polymers were synthesized via a polycondensation of dianhydride [such as 2, 2' -bis(3, 4-dicarboxyphenyl)hexafluoropropane dianhydride] and 2, 2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl. The uniaxial negative birefringent (n_x =n_y > n_z) polyimide substrates are achieved using a solution-casting method in conventional solvents, which exhibit thedesirable optical phase retardation [(n_x - n_z)×d] values from 50 to 400 nm varying with the film thickness. In thesepolyimide films, the long chain rigid molecules adopt intrinsic planar orientaion. In detail, the majority of phenylene-imiderings and phenylenes preferentially adopt nearly planar conformations parallel to the film substrae. In addition, these filmsalso possess high transparency (or transmittance) and little color shift. The unique color dispersion curve indicates that thistype of materials is very suitable for the applications in LCDs due to an excellent mimic for the retardation color dispersioncurve with respect to LC molecules. Significantly low in-plane retardation (< 1 nm) allows this new technology based film toachieve sufficiently high contrast ratio while highly negative retardation dramatically suppresses the gray scale inversion toimprove the viewing angle performance in a variety of new mode LCDs.

Integral imaging-based tabletop light field 3D display with large viewing angle

Light field 3D display technology is considered a revolutionary technology to address the critical visual fatigue issues in the existing 3D displays.Tabletop light field 3D display provides a brand-new display form that satisfies multi-user shared viewing and collaborative works,and it is poised to become a potential alternative to the traditional wall and portable display forms.However,a large radial viewing angle and correct radial perspective and parallax are still out of reach for most current tabletop light field 3D displays due to the limited amount of spatial information.To address the viewing angle and perspective issues,a novel integral imaging-based tabletop light field 3D display with a simple flat-panel structure is proposed and developed by applying a compound lens array,two spliced 8K liquid crystal display panels,and a light shaping diffuser screen.The compound lens array is designed to be composed of multiple three-piece compound lens units by employing a reverse design scheme,which greatly extends the radial viewing angle in the case of a limited amount of spatial information and balances other important 3D display parameters.The proposed display has a radial viewing angle of 68.7°in a large display size of 43.5 inches,which is larger than the conventional tabletop light field 3D displays.The radial perspective and parallax are correct,and high-resolution 3D images can be reproduced in large radial viewing positions.We envision that this proposed display opens up possibility for redefining the display forms of consumer electronics.

Development of Wearable Micro-actuator Array for 3-D Virtual Tactile Displays

A novel 4 by 4 array of electromagnetic micro-actuators operating on the principle of voice-coil actuators is presented. The intended application of the array is dynamic tactile stimulation, where multiple actuators generate an illusion of touching a moving pattern. In comparison to earlier designs [1-3], the device has smaller dimensions of 2.28 mm in diameter and 7 mm in length, which allowed its use in an array capable of hosting up to a 5 by 5 set of actuators with a rectangular shape covering an area of 18 mm by 21 mm. Using finite element analysis of several conceptual designs of actuators [1,4,5], it was established that the voice-coil type device (where the coil is the moving part) has most beneficial characteristics for the envisioned application. These include sufficient force over a relatively large distance, allowing tactile stimulation of surfaces with irregular shape, fast response, and small foot-print that matches the density of the tactile sensory neurons in the human finger. Eexperimental evaluation of the operation of neighboring actuators spaced at 3.3 mm apart, indicates that there is no crosstalk between the actuators. The resulting density exceeds that of previously reported alternative designs based on moveable permanent magnets [4,6]. Static force measurement indicate that each micro-actuator can produce at least 26 mN of repulsive force over a stroke of 2100 μm with a peak force of 34 mN. The driving circuit operates at 13.5V and generates a vibration frequency of up to 265 Hz without significant change of the force-displacement characteristics. In the higher frequency range (above 100 Hz) the actuator provides at least 15 mN of force over a slightly reduced stroke of 2300 μm, and a peak force of 21 mN. All of the above parameters meet the required threshold values of tactile human perception known from [2] and [3].

The evolution of courtship displays in Galliformes

Species in Galliformes have elaborate ritual courtship displays,often including strutting,fluffing of tail or head feathers,and vocal sounds that serve as excellent examples of sexual selection.According to the male orientation to the female while either posturing or moving,these courtship displays of gallinaceous species can be classified into three categories:1)‘frontal displays’,2)‘lateral displays’,and 3)‘both frontal and lateral displays’.Questions regarding which category of displays is the ancestral state and the evolutionary history of courtship displays in Galliformes remain unanswered.We collected and classified 131 species in terms of their courtship displays into the three categories listed above and carried out a large-scale comparative analysis to reveal the evolutionary trajectory of this trait.We found that the ancestral state of courtship displays of Galliformes involves both relatively short and straightforward frontal and lateral elements(i.e.,the category of‘both frontal and lateral displays’).Furthermore,ancestral trait reconstructions suggest that transitions from‘lateral displays’to‘frontal displays’occurred more frequently than the other way around(i.e.,from‘frontal displays’to‘lateral displays’).In addition,some transitions occurred from‘both frontal and lateral displays’to‘lateral displays’but not from‘both frontal and lateral displays’to‘frontal displays’.Ancestral state reconstruction of courtship displays at the root of the Galliformes phylogeny supports the‘both frontal and lateral displays’first scenario.This original state then evolved towards two extremes,either‘frontal displays’or‘lateral displays’,with more complicated and elaborate display components.Moreover,subsequent transitions occurred from‘lateral displays’to‘frontal displays’much more frequently than the other way around during the evolutionary history,indicating positive selection of‘frontal displays’.

COMPENSATION EFFECT OF POLYIMIDE THIN FILMS ON NORMALLY WHITE TWISTED NEMATIC LIQUID CRYSTAL DISPLAYS

The disadvantages of Normally White Twisted Nematic Liquid Crystal Display (NW-TN-LCD) were discussed. The reason that the negative birefringent polyimide thin films were used to compensate NW-TN-LCD to decrease off-axis leakage, improve contrast ratios and enlarge viewing angles was explained in this paper. A certain polyimide thin film was taken as an example to show compensation effect on NW-TN-LCD.

Functional-Material-Based Touch Interfaces for Multidimensional Sensing for Interactive Displays:A Review

Multidimensional sensing is a highly desired attribute for allowing human-machine interfaces(HMIs)to perceive various types of information from both users and the environment,thus enabling the advancement of various smart electronics/applications,e.g.,smartphones and smart cities.Conventional multidimensional sensing is achieved through the integration of multiple discrete sensors,which introduces issues such as high energy consumption and high circuit complexity.These disadvantages have motivated the widespread use of functional materials for detecting various stimuli at low cost with low power requirements.This work presents an overview of simply structured touch interfaces for multidimensional(x-y location,force and temperature)sensing enabled by piezoelectric,piezoresistive,triboelectric,pyroelectric and thermoelectric materials.For each technology,the mechanism of operation,state-of-the-art designs,merits,and drawbacks are investigated.At the end of the article,the author discusses the challenges limiting the successful applications of functional materials in commercial touch interfaces and corresponding development trends.