- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Development of Narrow Band LED Sources and Their Application to Dermatology
摘要： 半導体を用いた LED を光源とし，バンドパスフィルタを用いて超狭帯域光を得る技術を開発した．この光源をヒトの毛髪再生に応用し，有効な臨床結果を得ることができた．また超狭帯域 LED 照射が人の毛乳頭細胞を刺激し，mRNA の発現や蛋白生成が生じる事が分子生物学的に示された．更に皮膚深達度が高い超狭帯域赤色 LED 光照射が毛成長に有効であることがマウスの実験や，又培養ヒト毛乳頭細胞を用いた実験から分子メカニズムモデルが示された．逆に皮膚深達度が浅い超狭帯域緑色 LED 光照射は，創傷治癒に有効であった．このように，LED を光源とした超狭帯域光は，更に上述の研究を深化させるとともに，新たな光医学融合分野を発展させ新産業を開拓していくものと期待している．
关键词： Hair growth,Laser diode (LD),Human dermal papilla cells,Narrow-band LED (NB-LED),Light source,m-RNA,Wound healing,Band-pass filter
更新于2025-09-19 17:13:59
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Properties of indirect composites polymerized with laboratory light-emitting diode units
摘要： This study evaluated the light intensity of light-emitting diode (LED) units and the effects of five laboratory polymerization units on hardness and flexural strength. Two indirect composite materials (Cesead N and Solidex Hardura) were polymerized with five units (α-Light II, Hyper LII, LED Cure Master, Twinkle LED, and α-Light V). The light intensity of the devices was measured with a spectroradiometer. After light exposure, Knoop hardness number, flexural strength, and elastic modulus were determined. Evaluation of light intensity, using a wavelength range of 400 to 500 nm, revealed that the α-Light V and Hyper LII units had the highest light intensity. For the top surface of the two composites, the Knoop hardness number was significantly higher for the α-Light V and Hyper LII. For the two composite materials, flexural strength did not differ among the five polymerizing units. The present results indicate that the Cesead N and Solidex Hardura composites can be adequately polymerized with laboratory LED units.
关键词： microhardness,light source,light emitting diode,indirect composite,laboratory light polymerization
更新于2025-09-16 10:30:52
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Ultracompact and Unidirectional On-Chip Light Source Based on Epsilon-Near-Zero Materials in an Optical Communication Range
摘要： An on-chip light source is one of the essential components for integrated photonic circuits and quantum-information processing chips. To date, it has been a great challenge to construct an on-chip light source with high directionality, high collection efficiency, and ultrasmall feature size simultaneously in the optical communication range. Here, an on-chip light source, consisting of a circular paraboloid etched in an aluminum-doped zinc-oxide film, which is an epsilon-near-zero material, is experimentally realized at 1550 nm. Photons emitted from the a PbS quantum-dot cluster placed near the focal point of this paraboloid are reflected into a directional parallel beam due to the large impedance mismatch between aluminum-doped zinc oxide and ambient medium. An ultrasmall emission divergence angle of only ±3°, and an ultrahigh directional emission contrast ratio of 44 dB are achieved from the ultracompact device with a feature size of only 1.5 μm. Also, an ultrahigh collection efficiency of up to 92% is predicted by simulation. This work not only opens an alternative way for the realization of integrated photonic devices based on epsilon-near-zero materials, but also provides another method for the precise assembling of composite functional nanostructures.
关键词： nanomanipulation,on-chip light source,optical communication,epsilon-near-zero materials,quantum dots
更新于2025-09-12 10:27:22
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Development of LED-based illumination system for high-speed digital image correlation
摘要： The present work describes the design and development of a dedicated illumination system for application to high-speed digital image correlation. This type of application requires image acquisition to be performed with very short shutter times. This means that there is less time to integrate the incoming light and, as such, it is necessary to have significant light flux to acquire quality images. As such, illumination is usually the major concern in such high-speed imaging applications. The developed system uses a strobing high-power LED light source to tackle this issue, and illuminate the specimen with a large light flux during a very short period. This reduces the amount of heat that the specimen receives from the lighting source and has the advantage of enabling the use of cameras that would otherwise be unable to use such short shutter times effectively. In this paper, the whole design of the device is described. From the control electronics to the mechanical design, including the optical design of an appropriate reflector.
关键词： Structural Integrity,LED light source,Digital Image Correlation
更新于2025-09-12 10:27:22
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Creating business out of bright light: Scientists and the commercialization of synchrotron‐enabled research
摘要： Governments have attached a high priority to the commercialization of science and technology as a foundation for participation in the “new economy.” Scientists typically view their work in less commercial terms and focus on making contributions to knowledge. When governments invest in large-scale scientific infrastructure, like synchrotrons, they are increasingly concerned about the business and employment outcomes. This study examines the attitudes of synchrotron scientists at the Canadian Light Source (CLS) at the University of Saskatchewan toward government expectations and programs supporting commercialization. The scientists are, as a group, ambivalent toward strong commercialization efforts and feel that the expectations of government are unrealistic. Many, however, appreciate the financial and political requirements to focus on commercial activities, and a significant number see both research and societal benefits in engaging actively with private sector partners.
关键词： government expectations,synchrotron,Canadian Light Source,science and technology,commercialization
更新于2025-09-11 14:15:04
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The effects of strain and composition on the conduction-band offset of direct band gap type-I GeSn/GeSnSi quantum dots for CMOS compatible mid-IR light source
摘要： A type-I band Ge0.75Sn0.25/Ge0.682Sn0.158Si0.16 QD heterostructure is proposed for mid-IR light sources. The effects of strain and composition are theoretically investigated to optimize the band offset of the direct band gap GeSn QDs. It is found that the introduction of tensile strain and Si incorporation in the barrier layers are effective to increase the band offset in the conduction band. Besides, the band offset is expected to increase with the increase of Sn composition in QDs and the size of QDs.
关键词： mid-IR light source,GeSn QD
更新于2025-09-11 14:15:04
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Review of Incoherent Broadband Cavity-Enhanced Absorption Spectroscopy (IBBCEAS) for Gas Sensing
摘要： Incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) is of importance for gas detection in environmental monitoring. This review summarizes the unique properties, development and recent progress of the IBBCEAS technique. Principle of IBBCEAS for gas sensing is described, and the development of IBBCEAS from the perspective of system structure is elaborated, including light source, cavity and detection scheme. Performances of the reported IBBCEAS sensor system in laboratory and field measurements are reported. Potential applications of this technique are discussed.
关键词： supercontinuum light source,incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS),gas sensing,broadband light source,molecular spectroscopy
更新于2025-09-10 09:29:36
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Gunshot residue on dark materials: a comparison between infrared photography and the use of an alternative light source
摘要： The pattern of gunshot residue (GSR) includes important information about muzzle-target distance since a larger GSR distribution diameter indicates a larger shooting distance. GSR may not be visible to the naked eye when, for example, it is located on dark textiles. In such cases, further procedures need to be performed in order to visualize the pattern of GSR. Besides chemical procedures, an alternative light source or infrared photography can be utilized for non-destructive GSR visualization. In the work presented, these two techniques are compared based on shooting experiments using 26 different dark textiles. Within the range of the alternative light source, the use of a 440-nm light in combination with an orange-colored filter led to the best visualization of GSR in the form of fluorescent particles. Infrared photography, on the other hand, visualized GSR as dark particles, whereas—ideally—the dark textile reflected the infrared light and appeared bright. The comparison of both techniques revealed that the GSR distribution visualized by infrared photography was not identical to the GSR distribution visualized with 440-nm illumination in combination with an orange-colored filter. We concluded that infrared photography visualizes the inner powder soot zone, whereas illumination at 440 nm leads to fluorescence of the outer powder soot zone, which can be visualized using an orange-colored filter. Knowledge of this difference in visualization of the two powder soot zones is important for forensic practitioners assessing firing distances. In the literature, however, this difference is not noted as clearly.
关键词： Gunshot residue GSR,Alternative light source,Forensic light source,Crime scene investigation,Shooting distance,Infrared photography
更新于2025-09-10 09:29:36
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[IEEE 2018 IEEE 20th International Conference on e-Health Networking, Applications and Services (Healthcom) - Ostrava, Czech Republic (2018.9.17-2018.9.20)] 2018 IEEE 20th International Conference on e-Health Networking, Applications and Services (Healthcom) - A Robust PPG-based Heart Rate Monitor for Fitness and eHealth Applications
摘要： This paper presents the design and implementation of a robust heart rate monitor (HRM) based on photoplethysmography (PPG). This optical method is non-invasive and provides a convenient means of implementing a low-cost wearable HRM for eHealth applications. Our novel design consists of a light source that emits a modulated or unmodulated light signal through the finger tissue and measures the changes in the reflected light from the arterial blood. These reflections correspond well with the blood volume changes in synchrony with the heartbeat. Here we aim to provide a detailed description of how to design and implement an HRM device based on two approaches: 1) PPG using an unmodulated light source; 2) PPG using a modulated light source. Noise analysis in these devices enabled us to conceptualize and compare their performance and infer which one offers a better choice for optical heart rate monitoring. Based on the measurement results, the latter approach offers superior performance due to better noise cancellation and higher Signal-to-Noise Ratio (SNR) and is therefore robust against movement artefacts, power line noise, flicker noise of electronic components, as well as background environmental light interference.
关键词： Filter,Heart rate,Photoplethysmography,Unmodulated light source,Modulated light source
更新于2025-09-10 09:29:36
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A soft x-ray-ultraviolet (SUV) beamline and diffractometer for resonant elastic scattering and ultraviolet-vacuum ultraviolet reflectance at the Singapore synchrotron light source
摘要： A new beamline and a six-circle UHV diffractometer have been constructed at the Singapore Synchrotron Light Source with a broad energy coverage from 3.5 to 1500 eV. The beamline is optimized for ultraviolet-vacuum-ultraviolet optical reflectivity and resonant soft X-ray scattering with medium energy resolution over a broad energy range, achieved by using a self-focusing monochromator consisting of a plane mirror and three variable line spacing gratings. The unique character of the diffractometer comprises 4-circles in the vertical plane and 2-circles in the horizontal plane. Thirteen motions are available inside the UHV chamber with a base pressure of 1 × 10?9 mbar. Two sample holders working independently over a temperature range of 37 K–400 K are controlled by a closed-cycle cryostat, while the bottom holder inside a high field compact pulsed magnet is available for measurements requiring a magnetic field.
关键词： ultraviolet-vacuum ultraviolet reflectance,soft x-ray-ultraviolet beamline,resonant elastic scattering,diffractometer,Singapore synchrotron light source
更新于2025-09-10 09:29:36