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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]

Photoreversible color‐switching materials, which can reversibly change color in response to external light stimuli, have attracted increasing attention for their applications in time‐sensitive information storage and optical data storage fields. But most of the related materials are dyes or redox compounds with ultraviolet as the light source, dramatically limiting the cycling stability during discoloration processes. To address this problem, a near‐infrared (NIR)‐responsive rewritable paper via doping layered Co‐metal–organic frameworks (MOFs) into the stable polyvinylidene fluoride matrix is reported for the first time. Layered Co‐MOF shows a rapid color‐switching characteristic between orange and black blue upon NIR illumination on/off because of the interlayer spacing changes. Benefiting from the soft network structures of the matrix, Co‐MOF can be homogeneously distributed to deliver an outstanding reversibility performance, including rapid response, coloration in a short period, and decoloration within about 3 min in ambient air. The fabrication of new photoreversible color switching system holds great potential in communication security, which offers a viable pathway to achieve ink‐free photoreversible printing. [ABSTRACT FROM AUTHOR]

Thermal paper is widely used as a print medium for different applications but it constitutes a tricky substrate for fingermark visualization. An earlier work (J Forensic Sci 2015;60:1034) reported how to visualize fingermarks on untreated thermal paper by illuminating the item with a UV‐A light source. In the present paper, the potential of the near infrared (NIR) luminescence has been tested on thermal paper compared to the mentioned method. A controlled study was carried out utilizing eccrine enriched fingermarks. The promising outcomes obtained were further confirmed by performing a pseudo‐operational trial. Data clearly showed that the use of the NIR filter gave better results. Finally, preliminary tests suggested a different mechanism of reaction induced by fingermarks with respect to the one behind the thermal printing. Thus, NIR luminescence represents a refinement to the suite of optical examination processes, including the potential to increase the number of marks recovered in a noncontact, nondestructive way. [ABSTRACT FROM AUTHOR]

Compared with traditional paper relying on cellulose, the polymeric paper written by light can satisfy more multi‐environmental stability and reusability for sustainable development. Herein, proposed for the first time, a novel multifunctional polymeric paper with a patch‐sewing structure is designed, presenting the reversible writing/re‐writing performance. Meanwhile, a series of Fe‐based oxides with various submicron structures inherited from metal–organic framework templates are reported, in which the optimum one exhibited 95.04% absorbance from the finite difference time domain simulation and realized photothermal conversion instantaneously (soaring to 300 °C within 38 s). Given the distinguished mechanical properties (the tensile strength of 21.34 MPa and elongation at break of 546.06%), shape‐memory ability, and multi‐environmental stability, the composites are perfect for information recording. Due to the addition of the liquid crystal phase serving as the ink on the paper, the stress concentration and destruction can be recorded on the surface while it can recover to the initial situation by near‐infrared irradiation. Moreover, the remote writing with precision triggered by a focused light source can be achieved in multiple situations (air, water, and ice), which paved the way for the next generation of paper, especially in extreme conditions like deep‐water or aerospace. [ABSTRACT FROM AUTHOR]

The aim of this study is to examine the role of different formulations of calcium carbonates on the inkjet printing quality, with the use of cationic carboxymethyl cellulose (CMC)‐starch as a binder in the formation of the coating structure of paper to use for inkjet printing. For this, GCC (ground calcium carbonate), PCC (precipitated calcium carbonate) and ECC (eggshell calcium carbonate), which have been tried as new coating materials in recent years, are mixed in different proportions to form a different coated formulation and plastered on the newly produced paper surface. Then, optical and physical tests of the obtained samples are carried out. Then, printing properties of the papers on which drop‐on‐demand system inkjet printing is made are examined. According to the obtained data, it is determined that the optical properties of coated paper with GCC + PCC blends outperformed papers coated with other blends. According to the physical test results, GCC + PCC blended coated papers showed the best performance in breaking length and tear indices. ECC + PCC blended coated papers however showed the best performance in burst indices. It is determined that as the particle size of the calcium carbonates in the coating materials decreased, the burst indices value also decreased. This situation is the opposite for breaking length and tear indices values. When the inkjet printing features are examined, it is seen that the best results are obtained from GCC + ECC coated papers in general. The most optimal metamerism indices results, measured under three different light sources, are obtained on GCC + PCC coated papers. [ABSTRACT FROM AUTHOR]

Artworks based on Xuan paper or silk and painted by organic or inorganic pigments are highly responsive to light due to their materials and manufacturing technologies. They belong to the highest level of light responsive exhibits stipulated by International Commission on Illumination (CIE) and are vulnerable to fading and discoloration caused by radiation from light sources. The choice of light sources is the key of protection for artworks. It is indispensible and urgent to choose the lowest damage light sources according to the material characteristics of artworks. In this article, long‐term irradiation of typical light sources on various substrates and pigments was used as experimental method, and CIE DE2000 color difference formula was used as the evaluation index. The laws of the influence of different light sources on the color change of various materials were obtained, and the relative damage coefficients of light sources were calculated. Finally, eight kinds of light sources suitable for illuminating responsive artworks with typical material combinations were proposed. However, there are some limitations in the study, because the ancient Chinese Xuan paper and silk used as experimental objects in the experiment are yellowish. Thus, the models derived in this article are not suitable for choosing reasonable display light sources for other works of art. However, suitable light sources for different materials could be obtained by the calculation method used in this article. [ABSTRACT FROM AUTHOR]

Solid state light sources for projection displays have shown tremendous progress over the recent years. Their application usage is ranging from low luminance near to eye projection for augmented reality glasses to mainstream projectors. This presentation will share some of the latest progresses for laser and LEDs for Near‐to‐eye (NTE) displays and will describe important design challenges such as package integration and power efficiency. Besides, High Current LEDs are further pushing the limits and bring LED based projection light engines on eye‐to‐eye brightness level with lamp & laser‐based systems ranging up to 5,000 ANSI lumens. [ABSTRACT FROM AUTHOR]

Expansion of devices to access the virtual world is expected due to much attention to Metaverse in recent years. In particular, head mount display (HMD), smart glasses and AR glasses have been attracting attention as next‐generation mobile devices that will replace smart phones. Laser diodes and μLEDs are developed in various research institutes and companies as light sources for those devices. In this paper, we describe the development status of the laser diodes and the μLEDs, the technical problems of optimal adaptation to smart glasses, and introduce one of the solutions when using the laser diodes. [ABSTRACT FROM AUTHOR]

The latest achievements of GaN‐based laser diodes are summarized, focused on two topics: watt‐class high‐power edge‐emitting lasers and milliwatt‐class vertical‐cavity surface‐emitting lasers. These light sources have high efficiency and high reliability, which are suitable for various display applications such as laser projectors and/or ARIVR displays. [ABSTRACT FROM AUTHOR]

In recent years, Laser Diodes have been used in various applications. The first real application started with the release of compact disc(CD) players/digital versatile disks (DVD) players. Since blue and green lasers have been developed, and laser diodes have begun to be used for various display applications such as pico‐projector and Laser TV. In particular, recently, it is expected to be applied to head mount display(HMD) and Augmented reality(AR)/virtual reality(VR) glass applications as one of the new applications of single mode laser. This paper shows the laser diode and applications that have been developed so far, the trends of light sources for HMD and AR/VR glass applications that are expected in the future, the issues when using red green and blue laser diodes, and how to solve them. [ABSTRACT FROM AUTHOR]

The annulus light source method separates specular and diffuse components of reflected glare from display surfaces. Combining it with the variable aperture source method delivers source‐size dependence. Measuring diagnostic reflection samples and ePaper with mirror‐like or scattering surfaces confirmed that the source‐size dependence of reflected glare comes from haze scatter. [ABSTRACT FROM AUTHOR]

The AlGaInP red laser diodes were developed at the end of the 1980s, and since then we have been improving performance of laser diodes. Along with the improvement of laser performance, laser diodes has been used various applications such as optical discs and sensors. Recently, research and practical use of display applications and AR / VR devices are remarkable. In this paper, we mainly report on red laser diodes developed for display applications. [ABSTRACT FROM AUTHOR]

The inherent advantages of reflective e-paper displays (EPD) - wide viewing direction range and excellent readability even under bright sunlight - can be extended into low-light conditions by the addition of an integrated lighting unit (ILU) such as a front light. A methodology for predicting the viewing direction dependence of ambient contrast and color from display measurements and illumination models is here applied to reflective EPD where the ILU is switched on. First results show that an ILU improves the indoor performance of EPD, and enables their usage in environments with illumination otherwise inadequate for reading. [ABSTRACT FROM AUTHOR]

In recent years, the laser phosphor technology is becoming a mainstream one in the industry of projection display. In this paper, we first review the development of different light source technologies used in projectors. Thereafter, we review the evolution of our laser phosphor technology and then present its latest progress ‐ RGB laser phosphor. [ABSTRACT FROM AUTHOR]

High‐power red laser diodes are essential light sources for display applications. In this paper, we report the design, fabrication and characterization of single‐emitter 638nm laser diode with 4 W continuous wave power. The saturation and COD power of this 110um stripe width LD exceeds 4.0 W and 6.3 W at heatsink temperature of 20°C, respectively. At the operation power of 1 W, the Wall‐Plug efficiency can reach 38.3% and 41.8% for the continuous and pulsed wave with duty of 33.3%. The characteristics temperature T0 and T1 for this device is 62 K and 114K. [ABSTRACT FROM AUTHOR]

A polarization independent refractive index (RI) sensor with a RI sensitivity of 50 nm/RIU is demonstrated. The proposed RI sensor simply consists of a liquid crystal (LC) polymeric polarization grating film and one glass substrate. The wavelength shift over the refractive index of surrounding medium is investigated through anisotropic rigorous coupled‐wave analysis. Such a LC‐based polarization independent RI sensor not only enables the usage of an unpolarized light source but also manifests a high sensitivity, offering great potential for the integration with display systems. [ABSTRACT FROM AUTHOR]

Near‐eye displays often use narrow spectral bandwidth light sources to create virtual images. These sources provide wider color gamuts. However, the measurement instrument's spectral bandwidth and spectral stray light need to be considered. We evaluate these aspects in characterizing the display's color capability. [ABSTRACT FROM AUTHOR]

We combine a near‐infrared (NIR) sensitive organic photodetector with a high‐resolution 508 ppi oxide TFT backplane to create a large‐area thin NIR detector. Using a NIR light source the detector is capable of imaging the (pattern of) veins under the skin in reflection, leading to improved biometric authentication. [ABSTRACT FROM AUTHOR]

Due to high technology requirements for modern display devices such as flexible, high resolution, thinner and higher transmission of polarizations, non‐destructive testing methods for evaluating quality of thin film plate polarizers are in high demand. In this paper, a system which can be used to observe defects and inhomogeneity of these thin film plate polarizers such as wide grid polarizers and thin film coating polarizers is proposed. This system consists of a collimated backlight light source, an afocal system, a polarizer, a rotation stage and a CCD camera. The collimated backlight is used to produces a collimating beam to pass through a sample under test. The afocal system shrinks the size of light beam from sample to pass through the polarizer. Based on Malus's law, intensity of each pixel of images on CCD camera varies with the angle between the transmission axes of sample and polarizer, which is controlled by the rotation stage. Uniformity of thin film plate polarizers can be defined as polarization extinction ratio. This paper is to introduce the configuration and measurement theory, perform a setup used to implement it and present the experimental results from the uses of the setup. The results not only verify the validity but also confirm the feasibility of the proposed systems. [ABSTRACT FROM AUTHOR]

In order to solve the problem of lack of detail information and serious damage to the texture of the light source area when the dark channel prior dehazing algorithm processes fog images at night, this paper proposes a dehazing algorithm for nighttime fog images using the dark‐state point light source model. By introducing the dark state point light source model, the dark channel credibility weight factor and the pseudo dehazing image, combined with the nighttime image imaging model, the improved transmittance distribution is obtained, and the fog image at night is dehazed. The experimental results show that the image processed by the algorithm in this paper has little loss of texture details, high image definition, and the contrast between the light and dark of the image is better stretched, which can effectively dehaze the fog image at night. [ABSTRACT FROM AUTHOR]

Lawsone is a 2‐substituted‐1,4‐naphthoquinone derivative, which has been proposed as an alternative to the reagents currently used for fingermark detection on porous surfaces. 2‐substituted‐anthraquinones, which contain an additional conjugated benzene ring, have a similar chemical structure to that of lawsone. In this study, a new series of 2‐substituted‐1,4‐naphthoquinones and 2‐substituted‐1,4‐anthraquinones were synthesized and completely characterized by1H NMR,13C NMR, IR, and HPLC‐TOF/MS analyses. All newly synthesized 2‐substituted‐1,4‐quinones were investigated for their ability to develop latent fingermarks on porous surfaces, and this ability was compared with that of lawsone. Each fingermark developed was graded using an established method; thus, quantitative data were attributed to each fingermark. It has been demonstrated that the 1,4‐quinones react with amino acids present in latent fingermarks on selected paper surfaces to produce faint yellow‐orange impressions, which exhibit strong photoluminescence when illuminated with a forensic light source at 440 nm and observed through a red filter. None of the compounds caused background darkening. The results obtained were generally similar to those of lawsone, however, 8‐dibromo‐2‐(propylamino)naphthalene‐1,4‐dione and 5,8‐dibromo‐2‐(propylthio)naphthalene‐1,4‐dione yielded better results for copier paper and colored (blue) copier paper used in this analysis. To the best of our knowledge, this is the first study to examine the role of 1,4‐anthraquinone derivatives as potential fingermark development reagents. The results indicate that 1,4‐quinones have a potential to be used as reagents for enhancement of latent fingermarks. [ABSTRACT FROM AUTHOR]

Perovskite Quantum Dots (QDs) promise to deliver over 90% of Rec2020 color representation, the highest for RoHS compliant LCD displays. In this study, we strive to demonstrate the performance of LCD displays using QDot™ green emitting Perovskite QDs with various backlight architectures. Using different blue and red light sources, we fabricated four types of LCD display, which showed contrasting Rec2020 color gamut from 80 to 86% and brightness from 1000 to 2000 nits. With these impressive metrics, Perovskite Quantum Dots paves the way for mass adoption of the technology in the display field. [ABSTRACT FROM AUTHOR]

Highly efficient ultra‐violet lighting sources have been developed by using the Transfer Mold micro‐protrusion cathode arrays. The intensities of UV emissions for the Transfer Mold micro‐protrusion cathode arrays are 1.6–1.9 times as high as those of flat‐type cathodes, because the discharge efficiencies are enhanced by the 1.4–1.9 times increase of the charge densities. The highly efficient UV lighting sources can be obtained by using the Transfer Mold micro‐protrusion cathode arrays. The discharge efficiencies of Transfer Mold micro‐protrusion cathode arrays can be enhanced by the size‐controlling of base lengths from 1.6 µm to 30 µm. Therefore, a highly efficient Transfer Mold micro‐protrusion cathode arrays can be expected to be applied to large area and flat‐type UV lightings to a great extent. [ABSTRACT FROM AUTHOR]

We have proposed exposure method using Deep UV (DUV) exposure light to realize high resolution and high productivity in FPD lithography. [1] Here we show development concepts for our new G6 exposure tools with DUV light sources, and exposure test results with a test exposure tool. [ABSTRACT FROM AUTHOR]

VCSELs have recently received increasing attention from engineers and scientists. The progress of the research on GaN‐based VCSELs that allowed blue and green emissions are often one of the main topics discussed in this field. Combining these lasers with existing red VCSELs realized a full‐color light source with superior characteristics of VCSELs, such as small power consumption, circular beam profiles, and arraying ability. These features should be suitable for displays, for example, AR displays. In this report, a brief review of the recent progress regarding these VCSELs and their future applications is provided. [ABSTRACT FROM AUTHOR]

Solid-state light sources have multiple advantages over lamps for projection applications. Multiple solid-state technologies are used, including RGB LED, RGB laser, laser/LED hybrid or laser-phosphor light sources. This paper explores the advantages, disadvantages and future prospects of these lamp and solid-state light source technologies in projection applications. [ABSTRACT FROM AUTHOR]

OLEDs have been established as key light sources for high‐end displays. In addition to their ideal optical characteristics, the inherent compatibility with various form factors gives OLEDs a competitive edge with respect to conventional technologies. Such versatility in form factors makes OLEDs attractive not only for displays but also for wearable devices. In this respect, this talk explores OLEDs from the perspectives of wearable applications. The first part describes engineering required for highly flexible and stretchable OLEDs adopting non‐conventional electrodes. The second part then introduces OLEDs used in wearable healthcare applications such as pulse oximetry sensors. [ABSTRACT FROM AUTHOR]

We have developed a high‐resolution 508 ppi conformable imager using low‐temperature polysilicon thin‐film transistors (LTPS TFTs) on a plastic substrate together with organic photodetectors which has high sensitivity in wavelength of visible and near‐infrared regions (NIR). Using a NIR light source, both images of fingerprints/veins and pulse waves are successfully obtained. By adding red light source, both red pulse wave and NIR pulse are measured to calculate percutaneous oxygen saturation. [ABSTRACT FROM AUTHOR]

The projection displays which use lasers or laser hybrids as light sources have been widely applied in offices, homes, and theaters. The optical performance has been more enhanced recently with the development of the technologies, especially in light enhancement, color reproduction, luminance contrast, and dynamic range. The characterization and measurement for these projection displays become very important. The full‐frame projection technologies such as digital micromirror devices (DMDs), liquid crystal on silicon (LCOS), and liquid crystal display (LCD) projectors are typically concerned in the international standardization. The image quality of the projection system in graphics and video reproduction has been discussed in IEC WG10 "Working group of Laser Displays." In recent years, the IS (international standard)‐ IEC62906‐5‐1 Laser display and devices Part 5‐1 Measurement of Optical Performance for Laser Front Projection has been developed and reached the CDV stage. However, at this stage, there are some discussions among the expert's group on the issues of the optical measurement method. The main issues are the two topics related to the CLO (Color Light Output) and CGV (Color Gamut Volume). There are two opposing views within the working group which is a very challenging topic. According to IEC/ISO rule, the consensus is difficult to be achieved for more 2/3 favor support and less 1/4 against. In the traditional projectors, due to the graphic display is mainly used for black and white usage in the office application, the luminous flux output of the full white field was used as the primary indicator in the specification of the standard product. The light output is directly dependent on the power of the projection source. Therefore, a white light enhancement method is employed in some projection display technologies, and in such cases, the brightness of a color display is often lacking. However, this is no longer the general case. Manufacturer use different ways to boost the white lumen value for the full white screen, but the saturated colors do not get the same boost in brightness. The lumen ratio between the full white and the colors is no longer maintained. In the new standard we recommend using a regional grid pattern to test the projector's light output, including white light output and color light output. 1 Set of four colour tile test patterns used for projector characterization Moreover, the argue for color volume method is the derivative from the CLO/WLO issue. The main point is the argument between the applicability of CGV method (CIELAB usage) in HDR/SDR conditions. In this paper, we reviewed some of the most important aspects to provide a basic understanding the current development of laser projection display measurement in IEC standardization. 2 Example of range in colors produced by a given display as represented by the CIELAB color space [ABSTRACT FROM AUTHOR]

As advanced driving assistance systems pervade automobiles, drivers are exposed to more information than ever. Head up displays are expected to provide necessary contents depending on necessity and urgency. In this paper, the authors discuss and overview the promises and challenges of the technology. [ABSTRACT FROM AUTHOR]

Next generation automotive head-up display (HUD) could fundamentally change how OEMs utilize a HUD. A significantly larger virtual display area and vastly improved image quality are two of the many benefits. Along with the benefits come a unique set of challenges, which can be addressed by incorporating TI DLP® product solutions. This paper explores options for these challenges, including a comparison of different solid state illumination sources, and offers practical solutions for developers. [ABSTRACT FROM AUTHOR]

52 patients rated their operation 0-9 and 69 patients rated their operation 10 on their follow-up visit. Of the 410 patients, 234 (57.1%) gave complete responses to the questionnaires before and after surgery, of whom 126 (53.8%) and 119 (50.8%) did not have severe erectile and ejaculatory dysfunction before surgery, respectively. Sexual dysfunction occurred in almost half of the patients after rectal cancer surgery, and laparoscopy contributed to decreased postoperative male sexual dysfunction. [Extracted from the article]

Solid-state lighting has enabled configurable and tunable white-light sources. The available specification criteria, such as CCT, ΔuV, and CRI, are insufficient to characterize the color quality properties for these emerging technologies. An overview of new characterization methods will be presented with their potential for successful adoption by the lighting industry. [ABSTRACT FROM AUTHOR]

In this work, we describe the developments behind our “Brite3” generation rigid OLED lighting panels as well as bendable panels based on thin glass. We developed high brightness white OLEDs with excellent performance based on the stacking approach, achieving 80–90 lm/W on rigid panels and 60 lm/W on bendable panels. [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]

The backlight module is a key component for providing a light source for a Liquid Crystal Display (LCD), and its thickness has a direct impact on the thickness of the display. In order to reduce the thickness of the display product, it can be realized by reducing the thickness of the backlight module. In order to solve this problem, this paper proposes a design method for the microstructure of the optical film applied to the mini LED backlight module. The microstructured optical film designed in this paper can effectively improve the uniformity of brightness and realize the ultra‐thinning of the backlight module. Based on the principle of total reflection, the optical film microstructure is designed for the miniLED Lambertian light source. Under the assumption that the point light source is established, the extended light source is discretized into point light sources, and then the light energy that can be used for circulation is calculated for each point light source, and all point light sources The cyclic energy of is accumulated as the cyclic energy corresponding to the extended light source, and when its value is the largest, the best shape of the microstructure is obtained. The simulation results show that after adding the microstructured optical film, the illumination uniformity of the backlight module reaches 91.2%, which meets the uniformity requirements of the backlight module. The method of designing microstructured optical film proposed in this paper can effectively realize the ultra‐thinness of the backlight module and has strong practicability. [ABSTRACT FROM AUTHOR]

QPI is a new generation of spatial light modulator (SLM) that combines light source and light modulation at the pixel level, thus eliminating the waste in most existing SLMs where light is separately generated and modulated. This paper explains the QPI architecture and its 3D application and beyond. [ABSTRACT FROM AUTHOR]

Mercury‐free ultra‐violet light source, which were generated by high pressure plasma discharge sources in the atmospheric pressure region, have been proposed by using conventional dielectric barrier discharge. However, dielectric barrier discharge devices having conventional flat‐type electrodes as well as coaxial‐type electrodes, would be degraded by the avalanche and the deformation of electrode due to the secondary ion bombardment by high discharge‐starting voltages and abnormal discharges, under the conditions of ac voltages with typical peak‐to‐peak amplitudes of 1.5–6 kV. In this study, low dischargestarting voltage under high pressure can be expected by the enhancement of the local electric field concentration on cathode arrays having extremely uniform and sharp tips of Transfer Mold micro‐projection cathode arrays. These Transfer Mold microprojection cathode arrays have been fabricated by using Transfer Mold field emitter arrays (FEAs) fabrication method and evaluated for discharge characteristics as the first step for UV lighting applications. Transfer Mold micro‐projection cathode arrays can be useful for the extremely uniform plasma source applications having the low breakdown voltage, then expected to be applied to large area and flat‐type UV lighting applications to a great extent. [ABSTRACT FROM AUTHOR]

Recently, a novel approach has been proposed to produce ultrashort, fully coherent high-repetition-rate EUVand X-ray radiation by combining an energy recovery linac (ERL) with the angular-dispersion-induced microbunching methodology. It is critical to maintain microbunching when the beam passes through bending magnets between the undulators, which results in difficulties supporting multiple beamlines. In this paper, the design of a multiplexed emitting system consisting of multi-bend achromats, matching sections and radiators to facilitate the multi-beamline operation is presented. Theoretical analysis and numerical simulations have been carried out and the results show that the microbunching and beam quality can be well maintained after four times of bending. Five radiation pulses with a central wavelength of 13.5 nm and peak power at theMW level have been produced by the same electron beam via this multiplexed emitting system. The proposed method holds potential in the multi-beamline operation of ERL- or storage-ring-based coherent light sources. [ABSTRACT FROM AUTHOR]

A backlight module is a key component of a liquid crystal display(LCD). The thickness of the backlight module affects the thickness of the display. In this paper, a design method based on the segment‐weighted is proposed for the miniLED backlight, which could reduce the thickness of the backlight module while ensuring uniformity of luminance. A surface microstructure is designed by discretizing the extended light source into a point source and designing the corresponding point microstructure using the point source based design method and the segment‐weighted method. The simulation results show that the brightness uniformity is 70%. To further improve the brightness uniformity, a diffusion film is added with the optical distance(OD) of 0.8mm, and the brightness uniformity is improved to 88%. The optical film designed in this paper can effectively improve the brightness uniformity and realize the ultra‐thin performance of the backlight. [ABSTRACT FROM AUTHOR]

A study on creating a personal space lighting environment by employing three different layers of lighting - Task, Surround and Ambient lighting. Results showed that the visual quality of the lit space is enhanced by the addition of surround lighting. [ABSTRACT FROM AUTHOR]

Reflective liquid crystal display has the advantages of energy saving and environmental protection. When the ambient light is low, the front light source is required to provide illumination rays. The front light guide plate has a great influence on display luminance, contrast, etc. Based on Comprehensive considerations on luminance, uniformity, stray light, an analysis and evaluation method for front light guide source is proposed. Taking spherical dots as an example, the influence of dot radius and height on the comprehensive performance of the front light source is analyzed. The simulation results show that when the R:H is 3:1, the comprehensive evaluation parameters of the spherical structure are high, and the signal‐to‐noise ratio is increased by 240%, which can greatly improve the display performance. The analysis and evaluation method proposed in this paper can effectively guide the development of front light guide plates, shorten the development time and reduce the development cost. [ABSTRACT FROM AUTHOR]

Double-crystal monochromators (DCMs) are one of the most critical optical devices in beamlines at synchrotron sources, directly affecting the quality of the beam energy and position. As the performance of synchrotron light sources continues to improve, higher demands are placed on the stability of DCMs. This paper proposes a novel adaptive vibration control method combining variational modal decomposition (VMD) and filter-x normalized least mean squares (FxNLMS), ensuring DCM stability under random engineering disturbance. Firstly, the sample entropy of the vibration signal is selected as the fitness function, and the number of modal components k and the penalty factor x are optimized by a genetic algorithm. Subsequently, the vibration signal is decomposed into band frequencies that do not overlap with each other. Eventually, each band signal is individually governed by the FxNLMS controller. Numerical results have demonstrated that the proposed adaptive vibration control method has high convergence accuracy and excellent vibration suppression performance. Furthermore, the effectiveness of the vibration control method has been verified with actual measured vibration signals of the DCM. [ABSTRACT FROM AUTHOR]

In this papers, we use the stereoscopic color gamut to analy the performance of the color gamut in the laser display systems. Optimal RGB value is proposed and calculated by the luminance of the three primary colors. We calculated the coverage of different light sources to NTSC, Rec.709, Rec.2020 color gamut standards by grid method.Through the white point balancing of the multi‐primary display system, we have calculated the stereoscopic color gamut of 4 and 6 primaries display system. we designed a color discrimination experiment for ordinary people and people with color vision deficits, results show that laser display can improve the color recognition ability of human eyes. [ABSTRACT FROM AUTHOR]

Single-crystal chemical vapour deposition (CVD) diamond detectors are an established transmissive synchrotron beamline diagnostic instrument used for beam position and beam intensity monitoring. A recently commercialized alternative is silicon carbide (4H-SiC) devices. These have the potential to provide the same diagnostic information as commercially available single-crystal CVD diamond X-ray beam position monitors, but with a much larger transmissive aperture. At Diamond Light Source an experimental comparison of the performance of single-crystal CVD diamond and 4H-SiC X-ray beam position monitors has been carried out. A quantitative comparison of their performance is presented in this paper. The single-crystal diamond and 4H-SiC beam position monitors were installed in-line along the synchrotron X-ray beam path enabling synchronous measurements at kilohertz rates of the beam motion from both devices. The results of several tests of the two position monitors' performance are presented: comparing signal uniformity across the surface of the detectors, comparing kHz intensity measurements, and comparing kHz beam position measurements from the detectors. Each test is performed with a range of applied external bias voltages. A discussion of the benefits and limitations of 4H-SiC and single-crystal CVD diamond detectors is included. [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]

GLO:O8T/01dec21:jrs6102-fig-0001.jpg PHOTO (COLOR): 1 Photomontage (courtesy of David Long and the family): From the bottom left, proceeding anticlockwise: Derek Long at the start of his scientific career, as a member of Jesus College matriculating into the University of Oxford in 1943, his first book "Raman Spectroscopy", his last book "At the Sign of Atlas: the Life and Work of Joseph Moxon, A Restoration Polymath", his cottage "Three Houses" at Llandeloy, Roch, Dyfed where much of his writing was undertaken, his collection of classic woodworking planes (including a facsimile of the ivory Roman plane excavated at Goodmanham, which was the topic of his last paper published in JRS with Howell Edwards), and finally, Derek in his garden with his dog, Rupert gl This appreciation covers the 25 years from 1995 to the present and follows on from the survey of the predominantly spectroscopic career of Derek Long that was presented in a special issue of JRS in August 1995, on the occasion of his reaching his 70th birthday that year. That same year, he collaborated in what is believed to be his last scientific research paper in Raman spectroscopy, published in JRS that same year with the author, on the Raman spectroscopic analysis of the Goodmanham plane. It is noteworthy that this last paper of his in his beloved JRS brought together his diverse interests in classic woodworking tools, antiquarianism and in Raman spectroscopic analysis. [Extracted from the article]

The objective is to improve the recognition rate of white and near cotton‐coloured impurities in raw cotton against a single white visible light source background. A lightweight detection network model without anchor boxes based on improved YOLO v4‐tiny is proposed in this paper based on weighted feature fusion (WFF). The WFF strategy was used to improve the detection accuracy of the improved YOLO v4‐tiny algorithm. Meanwhile, to address the disadvantage that the anchor boxes obtained by the K‐means algorithm clustering do not have global features, the anchor‐free and tiny decoupled head schemes are used instead of the traditional coupled detection head. The improved algorithm was validated on the PASCAL VOC2012 dataset and the self‐built raw cotton impurity dataset collected by high‐speed camera. On the raw cotton impurity test set, compared to the original YOLO v4‐tiny model, the mean average precision (mAP) and frames per second (FPS) of the improved model increased by 10.35% and 6.9%, respectively. The proposed model detects white and near cotton‐coloured impurities with an accuracy of up to 98.78% and 98.00%. The experimental results show that the proposed method can effectively detect and identify impurities in raw cotton, which is of great practical significance for foreign matter detection and identification in cotton. [ABSTRACT FROM AUTHOR]

Edge-lit lightguides utilizing high efficiency LEDs are becoming widely adopted within the lighting industry due to their ability to manipulate and efficiently distribute the light from LED light sources in the direction and distribution desired by the lighting engineer [ABSTRACT FROM AUTHOR]