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7th Lighting Conference of the visegrad Countries, LUMEN v4 2018

作者： Slominski, Sebastian Faculty of Electrical Engineering Lighting Technology Division Warsaw University of Technology Electrical Power Engineering Institute Warsaw Poland

ISBN: (纸本)9781538679234

The last decade is the time of a very dynamic development of lighting technology. This development covers many areas that complement each other. The development of light sources, luminaires, measurement techniques and design methods make it necessary to develop new, effective tools to support the design and analysis of lighting equipment. In lighting technology, the most common analysis is made of such parameters as the illuminance, luminance distribution and discomfort glare, inseparable from the specificity of modern light sources. A characteristic feature of almost all of them is high luminance, on the level of 107- 108cd/m2. High luminance facilitates the design of very precise optical systems, but also it is strongly associated with the possibility of discomfort associated with glare. current methods of glare analysis in simulation software are related to conversion to the average luminance value of the luminaire, saved as simplified light parameters in electronic files (IES, LDT or similar). currently the calculations take place as a result of calculation ratio the value of luminous intensity in a given direction and the surface area of the dimension of the luminaires in the same direction. This can lead to a significant understatement of the luminance of the luminaire in any situation where luminous intensity comes from the heterogeneous luminance distribution on the surface of the luminaire. This situation most often occurs in luminaires with high-luminance light sources with a reflector system and in the case of multi-source luminaires with lenses - eg multi-LED luminaires. The paper presents advanced methods of luminance modelling of light sources developed as a result of digital measurements of luminance distributions. A comparative analysis of the accuracy of the simulation calculations of the analytical lighting fixture model will be presented. The results will be compared to the classic ray tracing methods used in currently used models. © 2018 IEEE.

关键词： Light sources

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Mauna Kea Spectroscopic Explorer (MSE): a preliminary design of multi-object high resolution spectrograph 7

Mauna Kea Spectroscopic Explorer (MSE): a preliminary design...

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Conference on Ground-Based and Airborne Instrumentation for Astronomy vII

作者： Zhang, Kai Zhou, Yifei Tang, Zhen Saunders, Will venn, Kim A. Shi, Jianrong McConnachie, Alan W. Szeto, Kei Wang, Lei Zhu, Yongtian Hu, Zhongwen Chinese Acad Sci Natl Astron Observ Nanjing Inst Astron Opt & Technol Nanjing 210042 Jiangsu Peoples R China Chinese Acad Sci Key Lab Astron Opt & Technol Nanjing Inst Astron Opt & Technol Nanjing 210042 Jiangsu Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Australian Astron Observ N Ryde NSW 2113 Australia Univ Victoria Victoria BC V8P 5C2 Canada Chinese Acad Sci Natl Astron Observ China Beijing 100012 Peoples R China CFHT Corp Kamuela HI 96743 USA Natl Res Council Canada Victoria BC V9E 2E7 Canada

ISBN: (数字)9781510619586

ISBN: (纸本)9781510619586

The Maunakea Spectroscopic Explorer (MSE) project will transform the CFHT 3.6m optical telescope to a 10m class dedicated multi-object spectroscopic facility, with an ability to measure thousands of objects with three spectral resolution modes respectively low resolution of R approximate to 3,000, moderate resolution of R approximate to 6,000 and high resolution of R approximate to 40,000. Two identical multi-object high resolution spectrographs are expected to simultaneously produce 1084 spectra with high resolution of 40,000 at Blue (401-416nm) and Green (472-489nm) channels, and 20,000 at Red (626-674nm) channel. At the Conceptual design Phase (CoDP), different optical schemes were proposed to meet the challenging requirements, especially a unique design with a novel transmission image slicer array, and another conventional design with oversize volume Phase Holographic (vPH) gratings. It became clear during the CoDP that both designs presented problems of complexity or feasibility of manufacture, especially high line density disperser (general name for all kinds of grating, grism, prism). At the present, a new design scheme is proposed for investigating the optimal way to reduce technical risk and get more reliable estimation of cost and timescale. It contains new dispersers, F/2 fast collimator and so on. Therein, the disperser takes advantage of a special grism and a prism to reduce line density on grating surface, keep wide opening angle of optical path, and get the similar spectrum layout in all three spectral channels. For the fast collimator, it carefully compares on-axis and off-axis designs in throughput, interface to fiber assembly and technical risks. The current progress is more competitive and credible than the previous design, but it also indicates more challenging work will be done to improve its accessibility in engineering.

关键词： Maunakea Spectroscopic Explorer Multi-object Spectrograph High Spectral Resolution Grism

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New tools for the design of freeform mirrors 18

New tools for the design of freeform mirrors

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Conference on current developments in Lens design and optical engineering XvIII

作者： Dilworth, Donald C. Opt Syst Design Inc POB 247 East Boothbay ME 04544 USA

ISBN: (纸本)9781510612082;9781510612075

Advances in manufacturing and measuring technology are making the use of freeform mirrors more practical than in the recent past. New degrees of freedom make it possible for designers to improve image quality while increasing the field of view and avoiding obscurations. But other issues arise when one designs a system with several mirrors, particularly packaging and clearance concerns: one must ensure that none of the mirrors gets in the way of the beam from any of the others, and one must consider the coordinate system in which the shapes are defined and in which they are measured, which are not necessarily the same. Addressing these concerns requires new computational tools.

关键词： Freeform aspheric mirrors beam clearance at mirrors

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Efficient green electroluminescence from 1,3-diphenyl-1H-pyrazolo[3,4-b]quinoxaline dyes in dye-doped polymer based electroluminescent devices

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DYES AND PIGMENTS 2018年 151卷 380-384页

作者： Gasiorski, P. Matusiewicz, M. Gondek, E. Pokladko-Kowar, M. Armatys, P. Wojtasik, K. Danel, A. Uchacz, T. Kityk, A. v. Czestochowa Tech Univ Fac Elect Engn Al Armti Krajowej 17 PL-42200 Czestochowa Poland Cracow Univ Technol Inst Phys Podchorazych 1 PL-30084 Krakow Poland AGH Univ Sci & Technol Fac Phys & Appl Comp Sci Al A Mickiewicza 30 PL-30059 Krakow Poland Univ Agr Inst Chem Dept Food Technol Ul Balicka 122 PL-30149 Krakow Poland Jagiellonian Univ Fac Chem Gronostajowa 2 PL-30387 Krakow Poland

We demonstrate several polymer based electroluminescent devices with active poly(N-vinylcarbazole) (PvK) layer doped with diphenylpyrazoloquinoxaline (PQX) dyes, RPQX, with lateral substituent R = Me, MeO, F or Cl. The electronic properties of these fluorescence emitters and relevant electroluminescence devices are characterized by optical spectroscopy techniques. The first absorption bands of the RPQX dyes considerably overlap with the fluorescence emission band of the host PvK matrix resulting in efficient radiative energy transfer between them. Using the measured electroluminescent spectra the emission color is characterized in CIE 1931 XYZ color space. The electroluminescence devices with a dye-doped active layer PvK:RPQX (R = Me, MeO, F or Cl) emit light with different shades of green color. The electroluminescent performance is characterized in terms of current efficiency determined from the luminance-current-voltage measurements. Depending on the fluorescent dopant it ranges from about 0.5 to above 2.2 cd/A. Such efficiency has been achieved on a simple dye doped device configuration without significant optimization. Accordingly, RPQX dyes may be considered as prospective fluorescence emitters for electroluminescent applications. The measured spectral characteristics of RPQX fluorescent emitters and relevant electroluminescent devices are compared with quantum-chemical DFT/TDDFT calculations based on re-parameterized long-range corrected functional and corrected linear response solvation. Relevant analysis, due to its good performance and predicability, appears to be helpful not only for understanding of the, origin of electronic transitions, but may serve as useful tool for chemical engineering dealing with design and synthesis of novel organic dyes for optoelectronic applications.

关键词： Pyrazoloquinoxaline dyes optical absorption spectra Electroluminescence spectra Electroluminescent devices OLEDs DFT/TDDFT calculations

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Unusual Electronic Transitions in Two-dimensional Layered SnSb2Te4 Driven by Electronic State Rehybridization

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Physical Review Applied 2019年第6期11卷 064045-064045页

作者： Wenhan Zhou Shiying Guo Shengli Zhang Zhen Zhu Shengyuan A. Yang Mingxing Chen Bo Cai Hengze Qu Haibo Zeng Key Laboratory of Advanced Display Materials and Devices Ministry of Industry and Information Technology College of Material Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China Materials Department University of California Santa Barbara California 93106 USA Research Laboratory for Quantum Materials Singapore University of Technology and Design Singapore 487372 Singapore Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Synergetic Innovation Center for Quantum Effects and Applications (SICQEA) Hunan Normal University Changsha 410081 China

Two-dimensional (2D) semiconductors, graphene, MoS2, and black phosphorus, have attracted tremendous interest for their unique mechanical, electronic, optical, and magnetic properties. However, few of the previously studied systems are perfect for practical electronic and optoelectronic applications due to limitations such as zero band gap, low carrier mobility, severe instability, or low absorption coefficient. Here, we predict an alternative ultrathick 2D semiconducting SnSb2Te4 with high mobility (2.782×104cm2⋅v−1⋅s−1) and large absorption coefficient (1.29×106). Intriguingly, the electronic band gap of 2D SnSb2Te4 exhibits an indirect-direct transition with increasing thickness, which is opposite to that observed in many 2D transition metal disulfides. Importantly, compared with the monolayer, bilayer SnSb2Te4 possesses stronger light harvesting, higher mobility, and larger on-state current by about one order of magnitude due to electronic states’ rehybridization with charge accumulation in the interlayer region. All these features suggest 2D SnSb2Te4 as a promising competitor for future high-performance infrared electronic and optoelectronic applications.

关键词： Electronic structure of atoms & molecules Electronic transitions First-principles calculations Optoelectronics

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optical design of an athermalised dual field of view step zoom optical system in MWIR 18

Optical design of an athermalised dual field of view step zo...

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Conference on current developments in Lens design and optical engineering XvIII

作者： Kucukcelebi, Doruk Roketsan Kemalpasa Mahallesi Sehit Yuzbasi Adem Kutlu Soka TR-06780 Ankara Turkey

ISBN: (纸本)9781510612082;9781510612075

In this paper, the optical design of an athermalised dual field of view step zoom optical system in MWIR (3.7 mu m-4.8 mu m) is described. The dual field of view infrared optical system is designed based on the principle of passive athermalization method not only to achieve athermal optical system but also to keep the high image quality within the working temperature between -40 degrees C and + 60 degrees C. The infrared optical system used in this study had a 320 pixel x 256 pixel resolution, 20 mu m pixel pitch size cooled MWIR focal plane array detector. In this study, the step zoom mechanism, which has the axial motion due to consisting of a lens group, is considered to simplify mechanical structure. The optical design was based on moving a single lens along the optical axis for changing the optical system's field of view not only to reduce the number of moving parts but also to athermalize for the optical system. The optical design began with an optimization process using paraxial optics when first-order optics parameters are determined. During the optimization process, in order to reduce aberrations, such as coma, astigmatism, spherical and chromatic aberrations, aspherical surfaces were used. As a result, athermalised dual field of view step zoom optical design is proposed and the performance of the design using proposed method was verified by providing the focus shifts, spot diagrams and MTF analyzes' plots.

关键词： Dual field of view step zoom optical design paraxial optics athermalization Mid Wave Infrared (MWIR)

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Development of an approach for Knowledge-Based System for CAD modelling

Development of an approach for Knowledge-Based System for CA...

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2018 International Conference on Materials Manufacturing and Modelling, ICMMM 2017

作者： Jayakiran Reddy, E. venkatachalapathi, N. Pandu Rangadu, v. Department of Mechanical Engineering. Annamacharya Institute of Technology and Sciences Rajampet516126 India Department of Mechanical Engineering JNTUA College of Engineering Ananthapuramu515002 India

In the process of reducing the production cost and satisfying the customer and to sustain in the current volatile market, the manufacturing companies are looking for alternate processes and methods of designing and manufacturing. The conventional CAD/CAM tools are developed to meet the general needs of the market, but not the rapid or specific requirements of the market or customer. Consequently, the companies are looking to customize or tailor the CAD/CAM tools to improve their effectiveness. For this reason, the scope of research in the field of customization of designing tools has improved rapidly in the recent time. This paper discusses an introductory approach for developing an knowledge based system for CAD modelling using customization process of an CAD/CAM tool. The intension behind the development of the system is to reduce the production time and cost. The effectiveness of the proposed system has been examined using an industrial case study. © 2017 Elsevier Ltd.

关键词： Computer aided design

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A lazy way to design infrared lens 18

A lazy way to design infrared lens

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Conference on current developments in Lens design and optical engineering XvIII

作者： Qiu, RongSheng Wu, JianDong Chen, LongJiang Yu, Kun Pang, HaoJun Hu, BaiZhen Shanghai Aerosp Control Technol Inst 1555 ZhongChun Rd Shanghai 201109 Peoples R China

ISBN: (纸本)9781510612082;9781510612075

We designed a compact middle-wave infrared (MWIR) lens with a large focal length ratio ( about 1.5:1), used in the 3.7 to 4.8 mu m range. The lens is consisted of a compact front group and a re-imaging group. Thanks to the compact front group configuration, it is possible to install a filter wheel mechanism in such a tight space. The total track length of the lens is about 50mm, which includes a 2mm thick protective window and a cold shield of 12mm. The full field of view of the lens is about 3.6 degrees, and F number is less than 1.6, the image circle is about 4.6mm in diameter. The design performance of the lens reaches diffraction limitation, and doesn't change a lot during a temperature range of -40 degrees C+60 degrees C This essay proposed a stepwise design method of infrared optical system guided by the qualitative approach. The method fully utilize the powerful global optimization ability, with a little effort to write code snippet in optical design software, frees optical engineer from tedious calculation of the original structure.

关键词： infrared optical system lens design athermalization filter wheel multispectral sensing

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Wannier90 as a community code: new features and applications

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JOURNAL OF PHYSICS-CONDENSED MATTER 2020年第16期32卷 165902-165902页

作者： Pizzi, Giovanni vitale, valerio Arita, Ryotaro Bluegel, Stefan Freimuth, Frank Geranton, Guillaume Gibertini, Marco Gresch, Dominik Johnson, Charles Koretsune, Takashi Ibanez-Azpiroz, Julen Lee, Hyungjun Lihm, Jae-Mo Marchand, Daniel Marrazzo, Antimo Mokrousov, Yuriy Mustafa, Jamal, I Nohara, Yoshiro Nomura, Yusuke Paulatto, Lorenzo Ponce, Samuel Ponweiser, Thomas Qiao, Junfeng Thoele, Florian Tsirkin, Stepan S. Wierzbowska, Malgorzata Marzari, Nicola vanderbilt, David Souza, Ivo Mostofi, Arash A. Yates, Jonathan R. Ecole Polytech Fed Lausanne Theory & Simulat Mat THEOS CH-1015 Lausanne Switzerland Ecole Polytech Fed Lausanne Natl Ctr Computat Design & Discovery Novel Mat MA CH-1015 Lausanne Switzerland Univ Cambridge Cavendish Lab Dept Phys Cambridge CB3 OHE England Imperial Coll London Dept Mat London SW7 2AZ England Imperial Coll London Dept Phys London SW7 2AZ England Imperial Coll London Thomas Young Ctr Theory & Simulat Mat London SW7 2AZ England RIKEN Ctr Emergent Matter Sci 2-1 Hirosawa Wako Saitama 3510198 Japan Univ Tokyo Dept Appl Phys Bunkyo Ku 7-3-1 Hongo Tokyo 1138656 Japan Forschungszentrum Julich Peter Grunberg Inst D-52425 Julich Germany Forschungszentrum Julich Inst Adv Simulat D-52425 Julich Germany JARA D-52425 Julich Germany Univ Geneva Dept Quantum Matter Phys Geneva Switzerland Swiss Fed Inst Technol Zurich Switzerland Tohoku Univ Dept Phys Sendai Miyagi Japan JST PRESTO Kawaguchi Saitama Japan Univ Basque Country Ctr Fis Mat E-20018 San Sebastian Spain Ecole Polytech Fed Lausanne Inst Phys CH-1015 Lausanne Switzerland Korea Inst Adv Study Hoegiro 85 Seoul 02455 South Korea Seoul Natl Univ Dept Phys Seoul 08826 South Korea Seoul Natl Univ Ctr Theoret Phys Seoul 08826 South Korea Ecole Polytech Fed Lausanne Lab Multiscale Mech Modeling LAMMM Lausanne Switzerland Jonannes Gutenberg Univ Inst Phys D-55099 Mainz Germany Univ Calif Berkeley Dept Phys Berkeley CA 94720 USA ASMS Co Ltd Shinagawa Ku 1-7-11 Higashi Gotanda Tokyo 1410022 Japan Sorbonne Univ IMPMC CNRS UMR 7590 Case 1154 Pl Jussieu F-75252 Paris 05 France Univ Oxford Dept Mat Parks Rd Oxford OX1 3PH England Johannes Kepler Univ Linz RISC Altenberger Str 69 A-4040 Linz Austria Beihang Univ Sch Microelect Fert Beijing Inst BDBC Beijing Peoples R China Swiss Fed Inst Technol Mat Theory Wolfgang Pauli Str 27 CH-8093 Zurich Switzerland Univ Zurich Dept Phys Wintherthurerstr 190 CH-8057 Zurich Switzerland Polish Acad Sci Inst High Pressure Phys Sok

Wannier90 is an open-source computer program for calculating maximally-localised Wannier functions (MLWFs) from a set of Bloch states. It is interfaced to many widely used electronic-structure codes thanks to its independence from the basis sets representing these Bloch states. In the past few years the development of Wannier90 has transitioned to a community-driven model;this has resulted in a number of new developments that have been recently released in Wannier90 v3.0. In this article we describe these new functionalities, that include the implementation of new features for wannierisation and disentanglement (symmetry-adapted Wannier functions, selectively-localised Wannier functions, selected columns of the density matrix) and the ability to calculate new properties (shift currents and Berry-curvature dipole, and a new interface to many-body perturbation theory);performance improvements, including parallelisation of the core code;enhancements in functionality (support for spinor-valued Wannier functions, more accurate methods to interpolate quantities in the Brillouin zone);improved usability (improved plotting routines, integration with high-throughput automation frameworks), as well as the implementation of modern software engineering practices (unit testing, continuous integration, and automatic source-code documentation). These new features, capabilities, and code development model aim to further sustain and expand the community uptake and range of applicability, that nowadays spans complex and accurate dielectric, electronic, magnetic, optical, topological and transport properties of materials.

关键词： Wannier functions band structure interpolation local orbitals real-space methods electronic structure Wannier orbitals density-functional theory

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Recent developments of genetically encoded optical sensors for cell biology

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BIOLOGY OF THE CELL 2017年第1期109卷 1-+页

作者： Bolbat, Andrey Schultz, Carsten European Mol Biol Lab Cell Biol & Biophys Unit D-69117 Heidelberg Germany

optical sensors are powerful tools for live cell research as they permit to follow the location, concentration changes or activities of key cellular players such as lipids, ions and enzymes. Most of the current sensor probes are based on fluorescence which provides great spatial and temporal precision provided that high-end microscopy is used and that the timescale of the event of interest fits the response time of the sensor. Many of the sensors developed in the past 20 years are genetically encoded. There is a diversity of designs leading to simple or sometimes complicated applications for the use in live cells. Genetically encoded sensors began to emerge after the discovery of fluorescent proteins, engineering of their improved optical properties and the manipulation of their structure through application of circular permutation. In this review, we will describe a variety of genetically encoded biosensor concepts, including those for intensiometric and ratiometric sensors based on single fluorescent proteins, Forster resonance energy transfer-based sensors, sensors utilising bioluminescence, sensors using self-labelling SNAP- and CLIP-tags, and finally tetracysteine-based sensors. We focus on the newer developments and discuss the current approaches and techniques for design and application. This will demonstrate the power of using optical sensors in cell biology and will help opening the field to more systematic applications in the future.

关键词： Calcium Fluorescence Imaging Kinases Microscopy

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