- 标题
- 摘要
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- 实验方案
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Optimal LED Filtering for Fluorescence Microscopy
摘要： LED illumination systems for fluorescence microscopy offer a wealth of benefits in comparison to traditional mercury and metal halide lamps, including ease of use, improved stability, and enhanced control. To fully realize these benefits, it is important to ensure that optical filters are configured correctly, which often can be confusing. However, without the correct filter configuration, experimental conditions can be suboptimal, and results may therefore be inaccurate. This article looks at optical filter setup in more depth, explaining the purpose and benefits of optimal LED filtering.
关键词： fluorophores,LED light source,optical filters,illumination systems,fluorescence
更新于2025-09-19 17:13:59
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Low-Cost Fabrication of Polymer Based Micro-Optical Devices for Application in Illumination, Sensing, and Optical Interconnects
摘要： Fabrication of desired micro structures in polymers is always of keen interest for applications in illumination optics, sensors and optical interconnects. The challenge is to fabricate structures in the sub-micron range but at low cost. Among other fabrication methods as described in [1], maskless lithography tends to be cost effective and can create sub-micron structures. Here, we present a simple and low-cost fabrication process chain for fabricating desired micro structures in polymer, i.e. PMMA. The microstructures are, for example, grating structures and straight waveguides. The fabrication is done using a maskless lithography setup which employs a spatial light modulator and a UV LED. For recording the microstructure pattern a grayscale photoresist, i.e. OrmoComp, is used, which is coated on the silicon substrate. For writing waveguides, a translation stage is included in the setup to stitch the single exposure patterns together to form a continuous waveguide structure, as can be seen in Fig. 1(c). For replication an intermediate stamp, which is stable at high thermal loads, is obtained by casting Polydimethyl siloxane (PDMS) in an oven for 15 mins at 100 0C. The stamp is then used to replicate the microstructures onto the Polymethyl methacrylate (PMMA) using a hot embossing system, i.e. Jenoptik HEX03. A 500 μm thick PMMA (Plexiglas XT99524, Thyssen Krupp) foil is placed on the PDMS (ELASTOSIL RT 607A/B) stamp and an embossing pressure of 7 kPa is applied for 4 mins. After cooling to a release temperature of 40 0C, the PMMA foil is removed manually.
关键词： micro-optical devices,PDMS,optical interconnects,illumination,polymer,sensing,maskless lithography,PMMA,hot embossing
更新于2025-09-19 17:13:59
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Modeling of photonic efficiency under controlled periodic illumination and continuous illumination
摘要： Controlled periodic illumination has been used to increase photonic e?ciency. However, the mechanism for the controlled periodic illumination is still under debate. Based on the excitation of the electron–hole pair, a mathematical model is developed to describe the photonic e?ciency under controlled periodic illumination and continuous illumination. The photonic e?ciency is inversely proportional to the average light intensity or duty cycle. The high photonic e?ciency at low light intensity is because the photocatalyst is closer to the thermal equilibrium state than at high light intensity, meaning a weak irreversibility. The present model shows that the controlled periodic illumination under a high maximum light intensity is virtually the same as continuous illumination under a low light intensity. Good agreement is found between the experimental data and predictions. The present model correctly predicts the dependence of the photonic e?ciency on the maximum light intensity with a very small relative error.
关键词： Controlled periodic illumination,Photonic e?ciency,Electron–hole pair
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - High-Efficiency InAs-InGaAs Quantum Dash Solar Cells Developed Through Current Constraint Engineering
摘要： In principle, quantum-dot intermediate band solar cell (QD-IBSC) operates at a higher current density than a III-V multijunction solar cell (MJSC). Due to this inherent property, heat management becomes important when it is operated under a high concentrated illumination. In this work, we propose one way to circumvent this issue, where a wide bandgap cell is placed on top of QD-IBSC, which acts as a current constraint cell, but instead leads to a higher VOC. We demonstrate a 32.1% efficiency under 225 suns with a bonded InGaP/GaAs widegap cell // InAs-InGaAs QDSC configuration.
关键词： wide bandgap cell,efficiency,VOC,III-V multijunction solar cell,concentrated illumination,quantum-dot intermediate band solar cell,MJSC,QD-IBSC,current constraint cell,heat management
更新于2025-09-19 17:13:59
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Electrical degradation behavior in metal oxide thin film transistor under negative bias-illumination stress
摘要： The electrical degradation behavior in metal oxide thin film transistor (TFT) under negative bias-illumination stress (NBIS) is one of the biggest obstacles for its applications in flat panel display. In order to solve this issue, Sr and N are doped in In2O3 thin film and significantly improve the NBIS stability of In2O3 TFT. In the addition, degradation in electrical performance caused by Sr doping. The XPS of SrInON thin film is tested to prove the reduction of the oxygen vacancy. the doping of N can also reduce
关键词： negative bias-illumination stability,thin film transistor,SrInON
更新于2025-09-16 10:30:52
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A Time-of-Flight Range Sensor Using Four-Tap Lock-In Pixels with High near Infrared Sensitivity for LiDAR Applications
摘要： In this paper, a back-illuminated (BSI) time-of-flight (TOF) sensor using 0.2 μm silicon-on-insulator (SOI) complementary metal oxide semiconductor (CMOS) technology is developed for long-range laser imaging detection and ranging (LiDAR) application. A 200 μm-thick bulk silicon in the SOI substrate is fully depleted by applying high negative voltage at the backside for higher quantum efficiency (QE) in a near-infrared (NIR) region. The proposed SOI-based four-tap charge modulator achieves a high-speed charge modulation and high modulation contrast of 71% in a NIR region. In addition, in-pixel drain function is used for short-pulse TOF measurements. A distance measurement up to 27 m is carried out with +1.8~?3.0% linearity error and range resolution of 4.5 cm in outdoor conditions. The measured QE of 55% is attained at 940 nm which is suitable for outdoor use due to the reduced spectral components of solar radiation.
关键词： CMOS image sensor,time-of-flight,backside-illumination,SOI detector,lock-in pixel
更新于2025-09-16 10:30:52
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Evaluation of Factors, Influencing the Accuracy of the Digital Model, Obtained by Laser Scanning
摘要： Measurements in terrestrial laser scanning (TLS) are not perfect and are subject to errors caused by various factors affecting the quality of the capture process and the resulting final product. Careful consideration of all these factors and errors provides a good basis for assessing the quality of the data and the information received. The accuracy of the 3D model obtained from laser scanning is influenced by the density of the measurements and the modelling methods. 3D modelling algorithms allow accuracy to be improved, but modelling software cannot solve all the problems, and it is impossible to achieve high quality 3D modelling without taking into account the factors that affect the accuracy of the measurements. The investigation of error sources in TLS measurements is rather complicated due to the large number of influencing factors that are interconnected. In addition to angular and longitudinal measurements, most scanning systems also offer a measure of the intensity of the reflected signal. Because the TLS is a non-reflective geodetic technology, it means that the measurement results are highly dependent on the reflectivity of the materials. The energy of the reflected signal depends on the following physical factors: object material properties, surface colour of the object, surface temperature, surface humidity, illumination. From the experimental studies it has been confirmed that the illumination and humidity of the scanned surfaces have a significant impact on their reflecting ability and the density of the received point cloud. Evaluation of digital model accuracy is made with а plane approximation and comparison with control points. Areas with different point densities were created in order to analyse the accuracy of 3D model and to determine the optimum scanning density.
关键词： accuracy,illumination,humidity,terrestrial laser scanning,TLS,point cloud,3D model,reflectivity
更新于2025-09-16 10:30:52
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AIP Conference Proceedings [AIP Publishing 15th International Conference on Concentrator Photovoltaic Systems (CPV-15) - Fes, Morocco (25–27 March 2019)] 15th International Conference on Concentrator Photovoltaic Systems (CPV-15) - Averaging the unaverageable: Defining a meaningful local series resistance for large-area silicon solar cells
摘要： From its definition based on lateral voltage drops, the local series resistance isn’t an arithmetically averageable quantity because voltage isn’t extensive; however, only such quantities can be averaged. Still, empirically it was found that averaging series images arithmetically provides rather reasonable results. Since the emitter of a large-area silicon solar cell is nearly an equipotential layer, one can linearize the description of the lateral voltage distribution (with respect to the forward-bias current and the emitter resistivity), from which we obtain an averageable local series resistance for the H-type grid geometry; its averageability stems from averaging the parallel paths of vertical current flow. By construction, the average obtained from this linear response theory is identical to the lumped value coming from the illumination intensity variation method, and it also shows the experimentally observed dependency on the forward-bias diode current.
关键词： local series resistance,linear response theory,arithmetic averaging,illumination intensity variation method,silicon solar cells
更新于2025-09-16 10:30:52
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Gr/TiO2 films with light controlled positive/negative charge for cell harvesting application
摘要： Light-induced cell harvest shows much potential in in vitro cell culture. In this work, a light-responsive monolayer graphene (Gr)/titanium dioxide nanodots (TN) film is designed and used for light induced cell harvest. It is found that after 20 min of 365 nm UV or 450 nm visible light illumination, different types of cells could be detached from the surface effectively. The highest cells detachment ratio reaches about 95%. The mechanism of such cell detachment is contributed to that light illumination generates charges accumulation, which, in turn, changes the conformation of extracellular matrix protein molecules adsorbed to a more disordered state, and eventually leads to the cells detachment. Such UV and visible light responsive Gr/TiO2 film could be a good candidate for surface with light-induced cell detachment property.
关键词： protein conformation,cell harvest,light illumination,surface charges,graphene/TiO2 nanodots
更新于2025-09-16 10:30:52
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First Steps towards Localized Opening of the Blood-Brain-Barrier by IR Laser Illumination Through the Rodent Skull
摘要： Glioblastoma, an aggressive malign tumor of the brain, is one of the most shattering diagnoses due to its very poor prognosis and limited treatment options. These options mainly consist of surgical or radiation therapeutic removal of as much tumor mass as possible, which unfortunately is almost always incomplete. Even worse, chemotherapy is of little use, as the special setup of the brain′s vessels severely limits the transit into the parenchyma of elsewhere efficient cytostatica. This Blood-Brain-Barrier (BBB) is for quite some time the target of sophisticated and nano-particle based transport mechanisms, however it is reported, that a boost of permeability for most of the brain can be achieved based on moderate temperature increase. One means to locally and reversibly increase the brain′s temperature and thus potentially opening the BBB may be achieved by illuminating the skull with infrared laser light, thus causing punctual heating and heat diffusion into the cortex. In extension of the common laser light guiding by glass fibres, we use a micro-positioned simple optics to focus a 1470 nm laser beam of approximately 500 ??m in diameter on the skull. The apparent opening of the BBB is evidenced by the localized spread of Evans Blue injected into the tail vein of said rat, binding to Albumin (64,6 kDa) in the body. This marker molecule is usually blocked from passing through the intact BBB, but under IR illumination for half a minute, it appeared in post mortem visible blobs. Temperature profiles and potential tissue damage are now under investigation by high speed thermal camera and post mortem histology.
关键词： Infrared Laser Illumination,Blood Brain Barrier Opening,Evans Blue
更新于2025-09-16 10:30:52