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Forensic document examination has been considered one of the most important fields in the forensic science. For this, a quick, effective, and cheap techniques for evaluation of forensic evidence is highly required. This study explores the comparison of A4 document paper by chemical and physical analysis. 16 of white A4 paper from different brands were analyzed by FTIR for investigation of structural characteristics. Video Spectral Comparator 8000 has been used to compare the A4 papers under different light source. The inorganic filler composition in the paper is also explored by ICP‐OES. The calcium carbonate content in document papers play a discriminant role which found to be between 16.02 % and 35.54 %. Also, water contact angle has been utilized in order to examine the surface of paper which is generally related to the inorganic filler and other additives. The WCA results ranged between 83° and 111° that enable quick and easy way to compare A4 document papers. The experimental results have demonstrated that besides FTIR methods, other methods such as ICP‐OES for elemental composition, WCA for wetting test, VSC for visualization under different light of source could have been applied for comparison of document papers in case of criminal cases. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This document discusses the optimization of display systems for augmented reality glasses. The author categorizes augmented reality devices into three groups based on field of view (FOV): small FOV (15-30 degrees), medium FOV (~50 degrees), and large FOV (>65 degrees). The author explores different choices and consequences for projectors, combiners, and dimmers in each category. They also discuss the use of different technologies, such as microLED panels, LCoS, OLED, and laser beam scanning. The document emphasizes the importance of optimizing the overall system, including illumination, projectors, displays, and waveguides, to achieve desired performance metrics such as resolution, efficiency, contrast, brightness, volume, and weight. [Extracted from the article]

People's interest in health care has increased these days. As various health care platforms are emerging, the corresponding market is also expanding. In order to monitor health conditions in everyday life, no physical damage should be made. One of the non‐invasive method, using light for sensing, is preferred due to this effect. In general, as the wavelength increases, light can penetrate deeper into the skin, leading to different bio‐signals. For example, All‐in‐One Sensor Display, which was announced by Samsung Display at SID 2023, used green light to selectively sense fingerprints on the skin surface by reducing the depth of skin penetration. To apply this progress to health care, red light can also be used for OPDs in the All‐in‐One Sensor Display. In this case, red light from red pixel is used as the light source. The light can reach blood vessels under the epidermis because the skin penetration depth is deeper than green light. The light reaching the blood vessel becomes a signal to gather biometric information. This biometric information is then collected at OPD as the signal reaches the OPD in the panel again. For these series of processes, an OPD capable of effective detecting of light in the 625 nm region emitted by red pixels is required. In this study, OPD was fabricated using RD‐01, a high absorption donor material suitable for red light absorption, and RA‐01, a non‐fullerene acceptor for mass production, to respond to red light near 625 nm. The EQE of the OPD was 25% at wavelength of 625 nm. In addition, absorption spectrum of the OPD covers the Red emission effectively. Our results represent that OLED panel can be used for not only fingerprint recognition but also health care platform. [ABSTRACT FROM AUTHOR]

Light is a popular choice as an indoor energy source for Internet of Things (IoT) end devices. However, indoor light sources are intermittent, which can disrupt the operation of IoT end devices, potentially leading to safety concerns or inaccurate data. Therefore, there is a growing need to develop a long‐duration power supply for IoT end devices. The energy from ambient light is harnessed to charge a supercapacitor through an energy manager chip. This supercapacitor serves as the power source for IoT nodes when the ambient light is unavailable. Nevertheless, as the voltage of the supercapacitor drops below the operating threshold, the IoT end node will eventually shut down. This paper proposes a circuit that utilizes a Joule Thief circuit, booster converter, and capacitor stack‐up circuit to extract the remaining energy from the supercapacitor and boost the voltage, thereby extending the operational lifespan of IoT end nodes. Additionally, capacitor stack‐up circuits significantly enhance charging efficiency. PSpice design and simulations confirm circuit feasibility. High‐efficiency charging and long‐duration IoT nodes suggest replacing traditional batteries with supercapacitors, reducing environmental impact. [ABSTRACT FROM AUTHOR]

In recent years, China's advanced light sources have entered a period of rapid construction and development. As modern X-ray detectors and data acquisition technologies advance, these facilities are expected to generate massive volumes of data annually, presenting significant challenges in data management and utilization. These challenges encompass data storage, metadata handling, data transfer and user data access. In response, the Data Organization Management Access Software (DOMAS) has been designed as a framework to address these issues. DOMAS encapsulates four fundamental modules of data management software, including metadata catalogue, metadata acquisition, data transfer and data service. For light source facilities, building a data management system only requires parameter configuration and minimal code development within DOMAS. This paper firstly discusses the development of advanced light sources in China and the associated demands and challenges in data management, prompting a reconsideration of data management software framework design. It then outlines the architecture of the framework, detailing its components and functions. Lastly, it highlights the application progress and effectiveness of DOMAS when deployed for the High Energy Photon Source (HEPS) and Beijing Synchrotron Radiation Facility (BSRF). [ABSTRACT FROM AUTHOR]

Photoplethysmography (PPG) technology enables the measurement of multiple physiological and psychological parameters with low‐cost wearable sensors and is reshaping modern healthcare. Advanced materials play a vital role in improving reliability and accuracy of PPG sensors. Recently, various advanced materials have been explored to optimize PPG sensor design, while some challenges exist toward large‐scale validation and mass production. This paper focuses on advanced materials applied in the photodetectors, light sources, and circuits of PPG sensors. The materials are categorized into four groups: inorganic, organic, nanomaterials, and hybrid materials. The properties and fabrication processes are summarized. Other technical details including the mode of operation, measurement sites, testing, and validation are discussed. The merits and limitations of the state of the art are highlighted to provide some suggestions for the future development of PPG sensors based on advanced materials. [ABSTRACT FROM AUTHOR]

Light detection and ranging (LiDAR) sensor is widely recognized as a critical component for accurate perception. However, there are a host of challenges that impede their performance, including low spatial resolution, high costs, large size, low reliability, and susceptibility to interference. It is challenging to overcome these issues using a single LiDAR module, necessitating the need for a review of current LiDAR technologies. The paper commences by introducing the fundamental principles of various laser rangefinders and discussing the optical modulation technologies used to prevent interference and ghost images. Next, the paper delves into the latest developments in laser technology, with a focus on enhancing the switching rate, compliance with eye safety regulations, miniaturization, and improving stability. One highly promising innovation is the photonic crystal surface emitting laser (PCSEL), a novel light source that boasts high‐speed, small divergence angles, and high‐power output. Finally, the paper discusses the advancements made in non‐solid‐state scanning and solid‐state scanning, such as improving stability, increasing scanning angles, and optimizing the manufacturing of mechanical and micro‐electromechanical systems (MEMS). Additionally, the paper highlights the recent advancements in nanotechnology, specifically metasurface technology, which offers superior capabilities such as beam deflection, enhanced field‐of‐view (FOV), and dynamic modulation. [ABSTRACT FROM AUTHOR]

In this paper, a new type of full attachment double‐sided liquid crystal display is designed. The liquid crystal screen and optical films are bonded by OCA called full‐ attachment LCD. The double‐sided display mentioned in this paper uses the same light source on both sides, and the light guide plate is made of glass material or nano material. The double‐sided display designed in this paper is ultra‐thin and the border is extremely narrow. It uses a full attachment optical architecture, higher utilization of light sources, and lower power consumption. Because it does not require a double‐sided backplane design, it is lighter. Its performance has been improved, and its cost has been reduced. [ABSTRACT FROM AUTHOR]

This paper describes how moiré plasmonic nanoparticle lattices can exhibit lasing action over a broad wavelength and wavevector range. Moiré nanolithography is combined with the PEEL (Photolithography, Etching, Electron‐beam deposition, and Lift‐off) process to fabricate in‐plane incommensurate lattices with optical properties beyond the restricted geometries of Bravais lattices. Because of increased rotational symmetry, moiré lattices support a larger number of transverse electric and transverse magnetic modes relative to their periodic base lattices. It is found that multidirectional lasing characteristics can be predicted by the symmetry of the moiré reciprocal lattice. Incommensurate moiré plasmonic lattices combine advantages of the dense band structures observed in aperiodic lattices with that of predicted modes in Bravais lattices for light‐based technologies in coherent light sources and multiplexed data transfer. [ABSTRACT FROM AUTHOR]

Cr3+‐activated broadband near‐infrared (NIR) phosphors are studied extensively for application in phosphor converted light‐emitting diode (pc‐LED), a new light source for substance testing based on NIR spectroscopy. However, the emission of Cr3+ is mainly located in the NIR I region (700–1000 nm) and many substances show the characteristic spectroscopy in the NIR II region (1000–1700 nm). In this paper, dual‐wavelength emission of NIR I and NIR II is realized in Cr3+ and Ni2+ codoped Zn3Ga2GeO8 (ZGGO) via energy transfer from NIR I emitting Cr3+ to NIR II emitting Ni2+. The photoluminescent properties of the doped ZGGO are studied as a function of doping concentration and the optimal concentrations of Cr3+ and Ni2+ are determined to be 0.04 and 0.003, respectively, with internal quantum efficiency (IQE) of 37.5%. The ZGGO:Cr3+, Ni2+ phosphor‐in‐glass (PiG), is prepared for fabricating PiG‐converted ultrabroadband NIR LEDs to avoid serious reabsorption of the NIR II emission as in the pc‐LED packaged using phosphor dispersed epoxy resin or silicone. The PiG pc‐LED offers photoelectric efficiency of 4.3%@20 mA and NIR output power of 17 mW@200 mA and shows stable spectral distribution against drive current compared to pc‐LED. [ABSTRACT FROM AUTHOR]

Accurate whiteness measurement is critical across various industries including textiles, paper, and detergents. With the advent of fluorescent whitening agents (FWAs), the assessment of whiteness has evolved from simply measuring reflectance to determining the spectral radiance factor (SRF) of materials. While multispectral imaging (MSI) can effectively measure object reflectance and colour, its accuracy is compromised by FWAs that significantly augment spectral reflectance. Thus, reliable whiteness measurement requires the determination of both reflectance and SRF. This article presents the design of a specialised light source equipped with an ultraviolet (UV) filter to provide adjustable illumination within an integrating sphere system. By tuning the position of the UV filter, multispectral images are captured of a fabric under varying UV exposures. These images are subsequently processed and combined to reconstruct full‐range visible spectrum information. This approach is shown to achieve high accuracy and spatial uniformity in quantifying the whiteness of textiles using MSI. [ABSTRACT FROM AUTHOR]

Luminescent metal halides, as a type of luminescent semiconductor material, offer advantages that fulfill the requirements of emerging light source devices, such as high luminescence efficiency, good thermal stability, and tunable colorful emission. Blue light being one of the three primary colors plays a crucial role in the field of lighting and colorful displays. However, the progress in device performance of blue‐light materials lags behind that of green and red‐light materials. Currently, there have been numerous reports on metal halide perovskite blue‐light materials, but a comprehensive review on the development and performance control of blue‐light metal halides is yet to be found. This paper provides a comprehensive summary of the design strategies and luminescence mechanisms of blue‐light perovskites with various luminescence centers, as well as their application progress in the fields of light‐emitting diodes (LEDs), X‐ray scintillators, information anti‐counterfeiting and encryption. It also explores possible directions for subsequent performance improvement. This work aims to offer valuable insights and recommendations for the future development of blue‐light metal halides, with significant implications for the fabrication of novel blue light devices and advancements in detection technology. [ABSTRACT FROM AUTHOR]

A photosensitive TFT sensor called bias TFT fabricated using simple amorphous silicon process in this paper. The photosensitive current of bias TFT is linearly related to the brightness of the top light source and inversely proportional to the size of the bias region. The photosensitivity current can be up to 10E‐8 amperes under 100 nits illumination. Among four shapes of bias TFTs, L‐type TFTs have the highest photo current. [ABSTRACT FROM AUTHOR]

The transition from LCD to OLED and µLED as dominant lighting sources for consumer displays in smart devices and AR/VR displays poses new challenges to light measurement. OLEDs and µLEDs exhibit completely different and far greater variations in their spectral distribution, for the measurement of which calibrations with standard light sources e.g. illuminant A are not optimally suited. Metrological traceability is thus particularly important for the interpretation of display measurements using (O)LED based light sources. The paper introduces experimental data on the traceable color accuracy of consumer display measurements based on different display technologies and therefore different variations in spectral distribution. We evaluate the influence of different calibration approaches and calibration sources. We also examine and compare the influence of internal and external spectral reference approaches on traceable error budgets. [ABSTRACT FROM AUTHOR]

In modern technology devices, an energy‐saving miniature near‐infrared (NIR) light source plays a critical role in non‐destructive, non‐invasive sensing applications and further advancement of technology. This paper reports the broadband NIR luminescence of Cr3+ clusters for designing phosphor‐converted NIR light‐emitting diodes as an alternative to typical isolated Cr3+ centers and Cr3+ ion pairs. Here, Cr3+ clusters form in the intermediate spinel structure of MgGa2O4 by utilizing the long‐chain edge‐shared octahedral dimers with the shortest bond distance between Cr3+ cations. Electron paramagnetic and magnetometry measurements confirm the isolated Cr3+ and Cr3+ clusters, resulting in NIR luminescence with three distinct emission centers. The formation of Cr3+ clusters in MgGa2O4 ensures stable internal quantum efficiency (≈94%), full‐width‐half‐maximum (248 nm), thermal stability (87%), and a radiant flux of ≈17.66 mW. This work offers a promising approach to NIR phosphor design and enhances the understanding of luminescence mechanisms in spinel and related structures. [ABSTRACT FROM AUTHOR]

Synchrotron light sources can provide the required spatial coherence, stability and control to support the development of advanced lithography at the extreme ultraviolet and soft X-ray wavelengths that are relevant to current and future fabricating technologies. Here an evaluation of the optical performance of the soft X-ray (SXR) beamline of the Australian Synchrotron (AS) and its suitability for developing interference lithography using radiation in the 91.8 eV (13.5 nm) to 300 eV (4.13 nm) range are presented. A comprehensive physical optics model of the APPLE-II undulator source and SXR beamline was constructed to simulate the properties of the illumination at the proposed location of a photomask, as a function of photon energy, collimation and monochromator parameters. The model is validated using a combination of experimental measurements of the photon intensity distribution of the undulator harmonics. It is shown that the undulator harmonics intensity ratio can be accurately measured using an imaging detector and controlled using beamline optics. Finally, the photomask geometric constraints and achievable performance for the limiting case of fully spatially coherent illumination are evaluated. [ABSTRACT FROM AUTHOR]

Folding screen phones have a larger display area compared to the traditional form of full‐screen phones, providing users with more usage scenarios. However, as the number of folding times increases, the functional layer of the display module will creep and wrinkles will appear on the surface of the folded screen, affecting the display effect of the screen. Current academic research has made progress in the mechanical simulation of folded screens, and surface flatness and contour curvature are used as quantitative characterization methods for simulation calculations. This paper proposes a quantitative characterization method of optical wrinkling for simulation results based on the basic theory of machine vision, by projecting a circular light spot at an angle of 45° to the screen onto the surface of the flexible screen, and observing the degree of aberration of the light spot at an angle of 135° to the screen as a failure criterion. The corresponding spot aberration value is calculated based on the coordinates of the grating, the coordinates of the light source and the position of the observation camera after CAE(Computer Aided Engineering) simulation. After comparing the experimental results with the simulation results, it is found that the simulation agrees well with the experiment. Finally, the two stacked structures of PET(polyethylene glycol terephthalate) and CPI(Colorless Polyimide), which are the covering layers of the screen, are taken as examples to illustrate that the present method can provide relevant clues for the structural design of the OLED(Organic Light‐Emitting Diode) screen, the selection of materials, and the mechanical problems in the bending process. [ABSTRACT FROM AUTHOR]

In response to the problems of the existing partition toning technology based on liquid crystal backlight needs to add metal physical grilles with high alignment accuracy to prevent the crosstalk of different colors and brightnesses of light between the partitions, this paper proposes a structural design of the optical cavity without grille and its key parameter value intervals, and puts forward a low‐color crosstalk evaluation method. Based on this method, the light output effect of the diffuser is evaluated, and the distance between the diffuser and the RGB mini‐LED light source as well as the structural parameters of the light‐guiding cavity between them are reasonably adjusted. The grilleless optical cavity structure studied in this paper has the advantages of simple structure, low cost and easy implementation, ensuring regional dimming and regional color mixing while further improving the color crosstalk phenomenon between the backlight partitions. [ABSTRACT FROM AUTHOR]

A composite of two or more materials usually results in enhanced specific properties. In this paper, a kind of composite material composed of Bi2WO6 with highly exposed {010} facets and 2D‐Co3O4 was prepared by a one‐pot reaction and then applied to decontaminate hydrocortisone in wastewater. The Bi2WO6/Co3O4 composite possessed a rose‐like surface microtopography self‐assembled from Bi2WO6 and Co3O4 nanosheets. The micro‐interface analysis showed that {110} facets of Co3O4 and {010} facets of Bi2WO6 were glued in situ and formed heterojunction. Additionally, the removal ability of hydrocortisone through Bi2WO6/Co3O4 varied under different light sources, which was 85.0 % under ultraviolet light and 97.3 % under visible light within 60 min. It was considered that Bi2WO6/Co3O4 was similar to a traditional heterojunction and the major reactive species was H2O2 under ultraviolet light, while it played a role as a Z‐scheme photocatalyst and the major reactive species was ⋅OH under visible light. Finally, product analysis of hydrocortisone demonstrated that the dexter chain broke whatever under ultraviolet or visible light, but the breakage of parent nucleus appeared only under visible light. This research revealed the enhanced catalytic properties of p‐n heterojunction catalysts and indicated the specifically exposed facets are promising for organic contaminants in water. [ABSTRACT FROM AUTHOR]

In recent years, photoelectrochemical (PEC) sensors have attracted much attention due to their inherent advantages, such as ease of operation, high sensitivity, and structural diversity. Compared with conventional PEC detection methods, self‐illuminated PEC sensors do not require an external light source, which makes them more attractive in terms of instrument miniaturization and simplified operation. Chemiluminescence (CL), a straightforward and efficient excitation source, can be harnessed for PEC sensors. In this review, we provide a summary on the recently reported chemiluminescence‐driven PEC sensors. Initially, we briefly describe the current chemiluminescent systems employed in PEC sensors, including luminol and peroxyoxalate CL systems. Subsequently, the CL‐exciting modes and the design strategies for self‐excited PEC sensors are explored. The subsequent sections of the paper predominantly focus on discussing the applications of such PEC sensors in the detection of various target analytes. Furthermore, future prospects for advancing these PEC sensors are discussed. [ABSTRACT FROM AUTHOR]

Manipulation of nanoparticles by light induced forces is widely used in nanotechnology and bioengineering. In normal cases, when a nanoparticle is illuminated by light waves, the transfer of momentum from light to the nanoparticle can push it to move along the light propagation direction. On the other hand, the lateral optical force can transport an object perpendicular to the light propagation direction, and the optical pulling force can attract an object toward the light source. Although these optical forces have drawn growing attention, in situ tuning of them is rarely explored. In this paper, tuning of both lateral optical forces and optical pulling forces is numerically demonstrated via a graphene/α‐phase molybdenum trioxide (α‐MoO3) bilayer structure. Under plane‐wave illumination, both the amplitude and direction of the optical forces exerted on a nanoparticle above this bilayer structure can be tuned in the mid‐infrared range. The underlying mechanism can be understood by studying the corresponding isofrequency contours of the hybrid plasmon‐phonon polaritons supported by the graphene/α‐MoO3 bilayer. The analytical study using the dipole approximation method reproduces the numerical results, revealing the origin of the optical forces. This work opens a new avenue for engineering optical forces to manipulate various objects optically. [ABSTRACT FROM AUTHOR]

Third- and fourth-generation synchrotron light sources with high fluxes and beam energies enable the use of innovative X-ray translucent experimental apparatus. These experimental devices access geologically relevant conditions whilst enabling in situ characterization using the spatial and temporal resolutions accessible at imaging beamlines. Here, Heitt Mjölnir is introduced, a heated miniature triaxial rig based on the design of Mjölnir, but covering a wider temperature range and larger sample volume at similar pressure capacities. This device is designed to investigate coupled thermal, chemical, hydraulic and mechanical processes from grain to centimetre scales using cylindrical samples of 10 mm × 20 mm (diameter × length). Heitt Mjölnir can simultaneously reach confining (hydraulic) pressures of 30 MPa and 500 MPa of axial stress with independently controlled sample pore fluid pressure < 30 MPa. This internally heated apparatus operates to temperatures up to 573 K with a minimal vertical thermal gradient in the sample of <0.3 K mm-1. This new apparatus has been deployed in operando studies at the TOMCAT (Swiss Light Source), I12 JEEP (Diamond Light Source) and PSICHE' (Synchrotron SOLEIL) beamlines for 4D X-ray microtomography with scan intervals of a few minutes. Heitt Mjölnir is portable and modular, allowing a wide range of 4D characterizations of low-grade metamorphism and deformational processes. It enables spatially and temporally resolved fluid-rock interaction studies at conditions of crustal reservoirs and is suitable for characterization of material properties in geothermal, carbonation or subsurface gas storage applications. Technical drawings and an operation guide are included in this publication. [ABSTRACT FROM AUTHOR]

In this paper, photograph of the sample environ‐ment set‐up at the TLS 15A1 experimental station of the NSRRC. The storage ring delivers a high‐quality light source, and the experimental station is equipped with state‐of‐the‐art instruments. Together, they enable the acquisition of high‐resolution complex structures, facili‐tating further research and applications. More details about this figure will be discussed by Dr. Chun‐Hsiang Huang and his co‐worker on page 721–731 in this issue. [ABSTRACT FROM AUTHOR]

Underwater organisms exhibit sophisticated propulsion mechanisms, enabling them to navigate fluid environments with exceptional dexterity. Recently, substantial efforts have focused on integrating these movements into soft robots using smart shape‐changing materials, particularly by using light for their propulsion and control. Nonetheless, challenges persist, including slow response times and the need of powerful light beams to actuate the robot. This last can result in unintended sample heating and potentially necessitate tracking specific actuation spots on the swimmer. To tackle these challenges, new azobenzene‐containing photopolymerizable inks are introduced, which can be processed by extrusion printing into liquid crystalline elastomer (LCE) elements of precise shape and morphology. These LCEs exhibit rapid and significant photomechanical response underwater, driven by moderate‐intensity ultraviolet (UV) and green light, being the actuation mechanism predominantly photochemical. Inspired by nature, a biomimetic four‐lapped ephyra‐like LCE swimmer is printed. The periodically illumination of the entire swimmer with moderate‐intensity UV and green light, induces synchronous lappet bending toward the light source and swimmer propulsion away from the light. The platform eliminates the need of localized laser beams and tracking systems to monitor the swimmer's motion through the fluid, making it a versatile tool for creating light‐fueled robotic LCE free‐swimmers. [ABSTRACT FROM AUTHOR]

A nanophotonic passively Q‐switched lasing element in the near infrared is proposed and theoretically investigated. It consists of a silicon‐rich nitride disk resonator enhanced with the contemporary MoS2/WSe2$\left(\text{MoS}\right)_{2} / \left(\text{WSe}\right)_{2}$ hetero‐bilayer and a graphene monolayer to provide gain and saturable absorption, respectively. The two‐dimensional materials are placed on top of the disk resonator and are separated by a spacer of hexagonal boron nitride. MoS2/WSe2$\left(\text{MoS}\right)_{2} / \left(\text{WSe}\right)_{2}$ emits at 1128 nm due to the radiative recombination of interlayer excitons after being optically pumped at 740 nm. Optical pumping is conducted in a guided‐wave manner aiming at achieving a high overall efficiency by critically coupling to a cavity mode near the pump transition. The response of the proposed pulsed laser is assessed by utilizing a coupled‐mode theory framework fed with linear finite‐element method simulations, rigorously derived from the Maxwell–Bloch equations. Following a meticulous design process and exploiting the guided pumping scheme, an ultralow lasing threshold of just 24.2 $24. 2 \text{ } \mu \text{W} $μW is obtained. Overall, the Q‐switched laser delivers pulsed light inside an integrated bus waveguide with mW peak power, ps duration, and GHz repetition rates requiring sub‐mW continuous wave pumping. These properties are highly promising for communication applications and highlight the potential of two‐dimensional materials for nanophotonic light sources. [ABSTRACT FROM AUTHOR]

Actuators utilizing snap‐through instabilities are widely investigated for high‐performance fast actuators and shape reconfigurable structures owing to their rapid response and limited reliance on continuous energy input. However, prevailing approaches typically involve a combination of multiple bistable actuator units and achieving multistability within a single actuator unit still remains an open challenge. Here, a soft actuator is presented that uses shape memory alloy (SMA) and mixed‐mode elastic instabilities to achieve intrinsically multistable shape reconfiguration. The multistable actuator unit consists of six stable states, including two pure bending states and four bend‐twist states. The actuator is composed of a pre‐stretched elastic membrane placed between two elastomeric frames embedded with SMA coils. By controlling the sequence and duration of SMA activation, the actuator is capable of rapid transition between all six stable states within hundreds of milliseconds. Principles of energy minimization are used to identify actuation sequences for various types of stable state transitions. Bending and twisting angles corresponding to various prestretch ratios are recorded based on parameterizations of the actuator's geometry. To demonstrate its application in practical conditions, the multistable actuator is used to perform visual inspection in a confined space, light source tracking during photovoltaic energy harvesting, and agile crawling. [ABSTRACT FROM AUTHOR]

The beamline optics and endstations at branch B of the Versatile Soft X-ray (VerSoX) beamline B07 at Diamond Light Source are described. B07-B provides medium-flux X-rays in the range 45-2200 eV from a bending magnet source, giving access to local electronic structure for atoms of all elements from Li to Y. It has an endstation for high-throughput X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) measurements under ultrahigh-vacuum (UHV) conditions. B07-B has a second endstation dedicated to NEXAFS at pressures from UHV to ambient pressure (1 atm). The combination of these endstations permits studies of a wide range of interfaces and materials. The beamline and endstation designs are discussed in detail, as well as their performance and the commissioning process. [ABSTRACT FROM AUTHOR]

As a representative of the fourth-generation light sources, the High Energy Photon Source (HEPS) in Beijing, China, utilizes a multi-bend achromat lattice to obtain an approximately 100 times emittance reduction compared with thirdgeneration light sources. New technologies bring new challenges to operate the storage ring. In order to meet the beam commissioning requirements of HEPS, a new framework for the development of high-level applications (HLAs) has been created. The key part of the new framework is a dual-layer physical module to facilitate the seamless fusion of physical simulation models with the real machine, allowing for fast switching between different simulation models to accommodate the various simulation scenarios. As a framework designed for development of physical applications, all variables are based on physical quantities. This allows physicists to analytically assess measurement parameters and optimize machine parameters in a more intuitive manner. To enhance both extensibility and adaptability, a modular design strategy is utilized, partitioning the entire framework into discrete modules in alignment with the requirements of HLA development. This strategy not only facilitates the independent development of each module but also minimizes inter-module coupling, thereby simplifying the maintenance and expansion of the entire framework. To simplify the development complexity, the design of the new framework is implemented using Python and is called Python-based Accelerator Physics Application Set (Pyapas). Taking advantage of Python's flexibility and robust library support, we are able to develop and iterate quickly, while also allowing for seamless integration with other scientific computing applications. HLAs for both the HEPS linac and booster have been successfully developed. During the beam commissioning process at the linac, Pyapas's ease of use and reliability have significantly reduced the time required for the beam commissioning operators. As a development framework for HLA designed for the new-generation light sources, Pyapas has the versatility to be employed with HEPS, as well as with other comparable light sources, due to its adaptability. [ABSTRACT FROM AUTHOR]

Holographic displays traditionally project full‐colored holograms time‐sequentially to achieve colored images. Time‐sequential image formation limits the achievable brightness levels. This work introduces a new method to achieve brighter images in holographic displays. Unlike the usual approach, our method allows three light sources to simultaneously illuminate the displayed holograms at different intensity levels. We optimize phase holograms along with the required intensity levels for each frame using our gradient‐descent based optimization pipeline. [ABSTRACT FROM AUTHOR]

We propose an autostereoscopic display with a directional backlight unit using an interleaved lens array and an organic electroluminescent display as an active light source. In the proposed system, the screen luminance per unit of power consumption is enhanced and the uniformity of luminance is improved. [ABSTRACT FROM AUTHOR]

Colloidal quantum dots (QD), the material discovered and fostered by laureates of Nobel Prize in Chemistry at 2023, exhibit impressive color purity and light conversion efficiency, are one of the most promising luminescent candidates in wide color gamut display application. Although the QD‐based color conversion techniques are gaining momentum in display industry, integration of QD into LED as on‐chip form still remain to be realized. The allocation of QD layer adjacent to the GaN blue LED light source are considered as the most viable, convenient, and efficient arrangement of adopting QD into photoluminescent scenarios. However, the extremely harsh working conditions QD endured in LED pose immense challenge and barrier to be surmounted. Herein, through bandgap engineering and overgrowth of silica‐aluminum oxide on QD, for the first time, we demonstrate mass‐producible LED chips integrated with QD as photoluminescent color converters via traditional dispensing process. Compared to conventional β‐sialon phosphors, the LED device incorporated with QD show comparable luminous efficacy and reach a wider benchmark of 105.1% NTSC and 98.5% DCI‐P3 color gamut. In addition, our devices exhibit decent lifetime under both working and storage conditions. Typically, while deployed under 60 °C and 90% relative humidity, our 2604 chip charged with a 20 mA working current maintains CIE 1931 color shift within ± 0.015 and luminosity reduction less than 10% after 1000 h continuous run. [ABSTRACT FROM AUTHOR]

We introduce a few novel design strategies to realize efficient deformable OLEDs, with emphasis on ultrathin OLEDs. Ultrathin OLEDs are used to create cylindrical light sources applicable to internal photo biomodulation for inner‐body phototherapeutics. Outcoupling technologies compatible with ultrathin form factors are also introduced. [ABSTRACT FROM AUTHOR]

We designed a color MR display based on a dual‐layers volume holographic light guide. The field of view can achieve 50 degrees. Each VHOEs as the in‐coupler and out‐coupler was produced with wavelength multiplexing process. Furthermore, we proposed the method to enhance the color uniformity by optimizing the light source. [ABSTRACT FROM AUTHOR]

In the anatomy of human eye, the role of iris is crucial since it controls the light level entering the eye and enhances the visibility. Here, we propose a soft contact lens type artificial iris actuated by eternal UV (ultra‐violet) light source, self‐regulating its effective aperture size by varying the crosslinking density of bio‐compatible polymer matrix doped with photochromic dye. For its self‐regulating characteristic, we cured HEMA‐based polymer matrix gradually from center to edge. Since the polymer matrix is polymerized by heat, we utilized NIR (near infra‐red) lamp and gradient grayscale patterned photomask for its gradual characteristic. Thereby, the crosslinking density of central position is higher compared to that of peripheral, causing slow switching dynamics. The gradient difference in switching dynamics leads to artificial iris gaining self‐regulation dynamics of effective aperture. The manufactured artificial iris shows advantage in blocking UV light, self‐regulating, and fast switching dynamics. The switching dynamics of artificial iris under bright and dim light adaptation are less than 50 seconds and 120 seconds, showing similar property with human iris. [ABSTRACT FROM AUTHOR]