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19th conference on current developments in Lens design and optical engineering

作者： Avendano-Alejo, Maximino Carmen Lopez-Bautista, M. Castaneda, Luis Univ Nacl Autonoma Mexico Inst Ciencias Aplicadas & Tecnol Apdo Postal 70-186 Mexico City 04510 DF Mexico Inst Politecn Nacl Escuela Super Med Plan San Luis & Diaz Mirson S-N Mexico City 11340 DF Mexico

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

We study the formation of caustic surfaces produced by cemented doublet lenses, considering a plane wavefront propagating parallel to the optical axis and neglecting the refractive index of the optical cement between two simple lenses which are in contact. We have already seen that the shape of caustic surfaces can represent the monochromatic aberrations that we call image errors;furthermore the shape of the caustic can be modified by changing the parameters of design for two conic lenses in contact, in such a way that if we are able to vanish the caustic, the optical system produces either an image without spherical aberration or longitudinal chromatic aberration reduced, commonly known as spherochromatism. The shape of the caustic surface is a function of the indices of refraction involved in the process of refraction, and all the parameters of two simple lenses. We provide an analytic equation for the caustic surfaces in a meridional plane and an example is presented.

关键词： Caustic Surfaces Cemented doublet lenses optical design Principal Surfaces

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Figures of merit of avalanche-mode silicon LEDs 5

Figures of merit of avalanche-mode silicon LEDs

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5th South African conference on Sensors, MEMS, and Electro-Optic Systems (SMEOS)

作者： Hueting, R. J. E. Dutta, S. Agarwal, v. Annema, A. J. Univ Twente MESA Inst Nanotechnol Enschede Netherlands LioniX Int Enschede Netherlands ItoM Enschede Netherlands

ISBN: (纸本)9781510627536

The silicon avalanche-mode light-emitting diode (AMLED) opens a route for on-chip opto-electronic applications in standard CMOS, both due to its relatively broad spectral overlap with the spectral responsivity of silicon photodiodes and due to its high speed capability. This work presents closed form models for the key figures of merit (FOMs) of AMLEDs, namely, current (or power) density, cut-off frequency, radiative efficiency, and specifically for optical data communication energy cost per photon. Their derivations are based on one-dimensional analyses of an abrupt single-sided (p(+)n or n(+)p) junction and of a p-i-n diode. TCAD simulations for optimized device structures, including the recently reported superjunction (SJ) LED, were performed to validate the model. Measurements on single-sided abrupt junctions and SJ diodes are shown to validate some of the modelled trends. The results show that a p-i-n or an SJ diode is favorable to a conventional single-sided junction diode for the AMLED design. In addition, as confirmed for conventional AMLEDs by earlier reports, the results indicate that for a yet higher efficiency the carrier supply should be increased. For this a combination of a separate minority carrier injector and SJLED is proposed, referred to as the injection-avalanche CMOS SJLED. However, more experimental optical data (e.g., absolute photon flux) are needed for a more accurate model validation.

关键词： avalanche CMOS figures of merit light-emitting diode p-i-n diode silicon superjunction

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The vector-apodizing phase plate coronagraph: design, current performance, and future development

arXiv

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arXiv 2021年

作者： Doelman, David S. Snik, F. Por, E.H. Bos, S.P. Otten, G.P.P.L. Kenworthy, M. Haffert, S.Y. Wilby, M. Bohn, A.J. Sutlieff, B.J. Miller, K. Ouellet, M. de Boer, J. Keller, C.U. Escuti, M.J. Shi, S. Warriner, N.Z. Hornburg, K.J. Birkby, J.L. Males, J. Morzinski, K.M. Close, L.M. Codona, J. Long, J. Schatz, L. Lumbres, J. Rodack, A. van Gorkom, K. Hedglen, A. Guyon, O. Lozi, J. Groff, T. Chilcote, J. Jovanovic, N. Thibault, S. de Jonge, C. Allain, G. vallée, C. Patel, D. Côté, O. Marois, C. Hinz, P. Stone, J. Skemer, A. Briesemeister, Z. Boehle, A. Glauser, A.M. Taylor, W. Baudoz, P. Huby, E. Absil, O. Carlomagno, B. Delacroix, C. Leiden Observatory Leiden University P.O. Box 9513 Leiden2300 RA Netherlands Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States Aix Marseille Univ CNRS CNES LAM Marseille France Steward Observatory University of Arizona 933 North Cherry Avenue TucsonAZ85721 United States Anton Pannekoek Institute for Astronomy University of Amsterdam Science Park 904 Amsterdam1098 XH Netherlands COPL Département de physique génie physique et optique Université Laval 2375 rue de la Terrasse QuebecG1V 0A6 Canada Department of Electrical and Computer Engineering North Carolina State University RaleighNC27695 United States Department of Physics University of Oxford Denys Wilkinson Building Keble Road OxfordOX1 3RH United Kingdom Harvard & Smithsonian | Center for Astrophysics 60 Garden St CambridgeMA02138 United States College of Optical Sciences University of Arizona 1630 E University Blvd TucsonAZ85719 United States 650 North A‘ohōkū Place HiloHI96720 United States Astrobiology Center of NINS 2-21-1 Osawa Mitaka Tokyo181-8588 Japan NASA-Goddard Space Flight Center GreenbeltMD United States Department of Physics University of Notre Dame South BendIN United States Department of Astronomy California Institute of Technology 1200 East California Blvd. PasadenaCA91125 United States SRON Netherlands Institute for Space Research Landleven 12 Groningen9747AD Netherlands National Research Council of Canada Herzberg 5071 West Saanich Road VictoriaBCV9E 2E7 Canada Department of Physics and Astronomy University of Victoria 3800 Finnerty Road VictoriaBCV8P 5C2 Canada Department of Astronomy and Astrophysics University of California Santa Cruz 1156 High Street Santa CruzCA95064 United States Naval Research Laboratory Remote Sensing Division 4555 Overlook Ave. SW WashingtonDC20375 United States Institute for Particle Physics and Astrophysics ETH Zurich Wolfgang-Paulistr. 27 Zurich8093 Switzerland UK

Over the last decade, the vector-apodizing phase plate (vAPP) coronagraph has been developed from concept to on-sky application in many high-contrast imaging systems on 8-m class telescopes. The vAPP is an geometric-phase patterned coronagraph that is inherently broadband, and its manufacturing is enabled only by direct-write technology for liquid-crystal patterns. The vAPP generates two coronagraphic PSFs that cancel starlight on opposite sides of the point spread function (PSF) and have opposite circular polarization states. The efficiency, that is the amount of light in these PSFs, depends on the retardance offset from half-wave of the liquid-crystal retarder. Using different liquid-crystal recipes to tune the retardance, different vAPPs operate with high efficiencies (> 96%) in the visible and thermal infrared (0.55 µm to 5 µm). Since 2015, seven vAPPs have been installed in a total of six different instruments, including Magellan/MagAO, Magellan/MagAO-X, Subaru/SCExAO, and LBT/LMIRcam. Using two integral field spectrographs installed on the latter two instruments, these vAPPs can provide low-resolution spectra (R∼30) between 1 μm and 5 μm. We review the design process, development, commissioning, on-sky performance, and first scientific results of all commissioned vAPPs. We report on the lessons learned and conclude with perspectives for future developments and applications. © 2021, CC BY.

关键词： optical transfer function

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design Model to Improve Task Scheduling in Cloud Computing Based on Particle Swarm Optimization

Design Model to Improve Task Scheduling in Cloud Computing B...

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IEEE NW Russia Young Researchers in Electrical and Electronic engineering conference (EIConRusNW)

作者： Almothana Khodar Liudmila v. Chernenkaya Iyad Alkhayat Hazim Abdulameer Fadhil Al-Afare Elena N. Desyatirikova Dept. of Computer Science Voronezh State University Voronezh Russia Highest School of Cyberphysic Control Systems Peter the Great St. Petersburg Polytechnic University St. Petersburg Russia Dept. of Information Systems and Networks Damascus University Damascus Syria Dept. of Computer Systems Middle Technical University Baghdad Iraq Dept. of Control Systems and IT Voronezh State Technical University Voronezh Russia

ISBN: (数字)9781728157610

ISBN: (纸本)9781728157627

Cloud computing is one of the most modern innovations that are growing rapidly in all technical fields because of its advantages in securing multiple resources and high speed in performance. It provides users connected via the Internet with a variety of storage and computing supplies. Cloud computing is both a catalyst and an enabler for major technological developments such as mobile computing, big data, and machine learning. With all these features, task scheduling has become one of the most difficult challenges facing the cloud, It plays a key role in the effectiveness of all cloud computing tools. Scheduling tasks means allocating tasks to the suitable virtual machine so that the course of computation can be executed to satisfy QoS constraints defined by users such as time to finish and expense. Most current optimization algorithms focus on only one aspect. In this paper, Depending on the characteristics of the swarm algorithm we will develop a model to solve the dilemma of task scheduling as well in order to get the fastest time to transfer tasks and the fastest time for execution with the lowest possible expense. In addition to that, we will develop a multi-purpose algorithm based on the PSO method to provide an optimal solution for the proposed model. The experimental consequences of this paper demonstrate that the proposed manner is more efficacious in expediting tasks and reducing expenses.

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Using effective medium theories to design tailored nanocomposite materials for optical systems 19

Using effective medium theories to design tailored nanocompo...

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19th conference on current developments in Lens design and optical engineering

作者： Werdehausen, Daniel Staude, Isabelle Burger, Sven Petschulat, Joerg Scharf, Toralf Pertsch, Thomas Decker, Manuel Carl Zeiss Corp Res & Technol Carl Zeiss Promenade 10 D-07745 Jena Germany Friedrich Schiller Univ Jena Abbe Ctr Photon Inst Appl Phys Albert Einstein Str 15 D-07745 Jena Germany Ecole Polytech Fed Lausanne Nanophoton & Metrol Lab CH-1015 Lausanne Switzerland JCMwave GmbH Bolivaralle 22 D-14050 Berlin Germany Zuse Inst Berlin Takustr 7 D-14195 Berlin Germany Carl Zeiss SMT GmbH Semicond Mask Solut Carl Zeiss Promenade 10 D-07745 Jena Germany Fraunhofer Inst Appl Opt & Precis Engn Albert Einstein Str 7 D-07745 Jena Germany

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

Modern optical systems are subject to very restrictive performance, size and cost requirements. Especially in portable systems size often is the most important factor, which necessitates elaborate designs to achieve the desired specifications. However, current designs already operate very close to the physical limits and further progress is difficult to achieve by changing only the complexity of the design. Another way of improving the performance is to tailor the optical properties of materials specifically to the application at hand. A class of novel, customizable materials that enables the tailoring of the optical properties, and promises to overcome many of the intrinsic disadvantages of polymers, are nanocomposites. However, despite considerable past research efforts, these types of materials are largely underutilized in optical systems. To shed light into this issue we, in this paper, discuss how nanocomposites can be modeled using effective medium theories. In the second part, we then investigate the fundamental requirements that have to be fulfilled to make nanocomposites suitable for optical applications, and show that it is indeed possible to fabricate such a material using existing methods. Furthermore, we show how nanocomposites can be used to tailor the refractive index and dispersion properties towards specific applications.

关键词： Nanocomposites Nanomaterials optical materials optical design optical Systems Dispersion engineering Effective medium theory Mie theory

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design of On-Line Measurement System for Fine Particle Number Concentration of vehicle Exhaust Based on Diffusion Charge Theory 6th

Design of On-Line Measurement System for Fine Particle Numbe...

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6th International conference on Frontier Computing, FC 2018

作者： Cong, Zhouyang Yu, Tongzhu Gui, Huaqiao Yang, Yixin Zhang, Jiaoshi Cheng, Yin Liu, Jianguo Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics the Chinese Academy of Sciences Hefei230031 China University of Science and Technology of China Hefei230026 China Anhui Provincial Key Laboratory of Environmental Optical Monitoring Technology Hefei230031 China

ISBN: (纸本)9789811336478

The concentration of particulate matter is an important parameter to measure exhaust emissions from motor vehicles. This article discusses the design of an on-line measurement system for fine particle number concentration. Based on charging models in continuum regime, a unipolar charger with free electron capture function was designed. After a high-sensitivity I–v conversion circuit was built in the micro current detection module, we designed a wide-range Faraday cup electrometer. The experimental results show that the charger can efficiently charge 23 nm–2.5 μm particles, achieve a stable discharge with an average discharge current of −5 μA (relative error is less than 1%). And a wide-range Faraday cup can achieve a ±500 pA range, fA—level electrical signal measurement. Compared with the AvL-APC 489 instrument, the integrated system experimental test is better than 87.2%, which can meet the on-line testing requirements for the concentration of motor vehicle exhaust particulates. © 2019, Springer Nature Singapore Pte Ltd.

关键词： Electrometers

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design and Implementation of Hybrid Micro-Grid in MATLAB for Fault current Analysis in Different Modes of Micro-Grid Operations

Design and Implementation of Hybrid Micro-Grid in MATLAB for...

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International conference on Recent developments in Control, Automation and Power engineering (RDCAPE)

作者： Gurpreet Kaur Anupama Prakash Associate K.Uma Rao Amity University Noida UP R.V College of Engg. Bangalore

A good protection system is a backbone of any grid. With the injection of distributed generators in the grid, the traditional protection system consisting of overcurrent relay is not sufficient to protect the system. It is therefore very important to understand the level of fault currents in the micro grids when they are connected to the grid and when they operate independently in the islanded mode. In this paper a micro grid consisting of different distributed generators such as wind turbine, solar panel, the fuel cell along with DC to DC converter and a 3-φ inverter feeding a 3-φ AC load is simulated in MATLAB. The simulated microgrid has been subjected to various faults in both grid connected and islanded mode and fault current levels are discussed in detail. The analysis done in this work is helpful in designing an effective and reliable protection scheme for the hybrid microgrid when operated in islanded and grid connected modes.

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Optimizing trefoil phase plates design for color wavefront coding 19

Optimizing trefoil phase plates design for color wavefront c...

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19th conference on current developments in Lens design and optical engineering

作者： Olvera-Angeles, Miguel Padilla-vivanco, Alfonso Ortega, Karina Sasian, Jose Schwiegerling, Jim Arines, Justo Acosta, Eva Univ Politecn Tulancingo Hidalgo 43629 Mexico Univ Arizona Coll Opt Sci Tucson AZ 85721 USA Univ Santiago de Compostela Fac Fis Santiago De Compostela 15782 Spain

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

Wavefront coding refers to the use of a phase modulating element in conjunction with deconvolution to extend the depth of focus of an imaging system. The coding element is an asymmetrical phase plate shape, for most applications in the form of a trefoil or a cubic polynomial. Phase plates with trefoil shape generate not only the desired amount of trefoil aberration but also spherical aberration. It has been recently shown that a wavefront coding based optical system shows high tolerance to spherical aberration for monochromatic images;however, the depth of focus is considerably shortened for color images. In this work, we will show how to modify the shape of a phase plate in order to optimize its performance for color imaging. The design parameters of the phase plate are obtained by minimizing a merit function by means of genetic algorithms developed for this purpose. The evaluation of the optical characteristics of the phase plates for a feedback with the optimization algorithm is obtained by Zemax. Results will be illustrated by numerical simulations of color images.

关键词： Wavefront coding spherical aberration color imaging optimization genetic algorithms

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optical design and Predicted Performance of the WFIRST Phase-B Imaging Optics Assembly and Wide Field Instrument 19

Optical Design and Predicted Performance of the WFIRST Phase...

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19th conference on current developments in Lens design and optical engineering

作者： Pasquale, Bert A. Casey, Thomas Marx, Catherine Gao, Guangjun Armani, Nerses Content, David Hagopian, John Jurling, Alden Jackson, Clifton Liu, Alice Whipple, Art Murray, Jacob NASA Goddard Space Flight Ctr Greenbelt MD 20771 USA AS&D Inc 7000 Muirkirk Meadows Dr Beltsville MD 20705 USA Sigma Space Inc 4600 Forbes Blvd Lanham MD 20706 USA SGT Inc 7701 Greenbelt Rd Greenbelt MD 20770 USA ATA Aerosp Inc Greenbelt MD 20770 USA Conceptual Analyt Inc Glenn Dale MD 20769 USA Rose Hulman Inst Technol Terre Haute IN 47803 USA

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

Now in Phase-B, the architecture of the Wide-Field Infra-Red Survey Telescope (WFIRST) payload has matured since 2013 to accommodate various opto-mechanical constraints. Based on a 2.4-meter aperture Forward optical Assembly (FOA), the Imaging Optics Assembly (IOA) provides corrected optical fields to each on-board instrument. Using a Three Mirror Anastigmat (TMA) optical design, the Wide-Field Channel (WFC) provides similar to 1/3-square degree of instantaneous field coverage at 0.11 arcsecond pixel scale. The WFC as-built predictive analysis anticipates near diffraction-limited imaging over a focal plane of 300.8 million pixels, operating in seven panchromatic bands between 0.48 -2.0 mu m, or a 1-octive multi-spectral imaging mode from similar to 0.95-1.93 mu m. The IOA provides the Coronagraph Instrument (CGI) a collimated beam with very specific wavefront constraints. We present configuration changes since 2013 that improved interfaces, improved testability, and reduced technical risk. We provide an overview of our Integrated Modeling results, performed at an unprecedented level for a phase-A study, to illustrate performance margins with respect to static wavefront error, jitter, and thermal drift.

关键词： Space Instrumentation Astronomical Optics Imaging Systems Telescopes Dark Energy Spectroscopy Systems engineering Integrated Modeling

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design of coded structured light based on square-shaped primitives 19

Design of coded structured light based on square-shaped prim...

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19th conference on current developments in Lens design and optical engineering

作者： Lau, Chi-Chung Sun, Ching-Chern Yang, Tsung-Hsun Yu, Yeh-Wei Chou, Si-Min Ind Technol Res Inst Green Energy & Environm Res Labs Bldg 24195Sec 4Chung Hsin Rd Hsinchu 31057 Taiwan Natl Cent Univ Dept Opt & Photon Kwoh Ting Opt & Photon Bldg300 Jhongda Rd Taoyuan 32001 Taiwan

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

This paper presents a new pattern design for encoding structured light for scanning 3D surface and the decoding process. The basic unit of the pattern is a code-block that contains one central label and eight square-shaped primitives that provide two functions: code-block indexing and point-positions for triangulating. The square-shaped primitive has one notch in a different position to represent 8 digit numbers, which are easily to convert label to number for indexing code-block. One primitive also contributes five point-positions, centroid and four extreme, for triangulating and estimating 3D information. The design of code-block has eight 8-bit numbers allowing a higher error-tolerant and providing better resolution in 3D reconstruction. Experiment shows that the proposed pattern is suitable for indoor mapping and large scene scanning.

关键词： coded structured light primitives 3-D data acquisition computer vision

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