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current developments in Lens design and optical engineering XX 2019

作者： Lee, Xuan-Hao Lin, Shih-Kang Yu, Yeh-Wei Yang, Tsung-Hsun Sun, Ching-Cherng Department of Optics and Photonics National Central University Taoyuan City32001 Taiwan Department of Optics and Photonics Feng Chia University Taichung City40724 Taiwan

ISBN: (数字)9781510629028

ISBN: (纸本)9781510629011

In this paper, an efficient lighting design for indoor sport field is presented. The average illuminance for the indoor sport field with eight playing courts can be achieve to 500 lx at a 11.2 m of the lamp's mounting height. Besides, because of specific arrangement of luminaires, the proposed lighting design can effectively reduced the glare effect and provide a comfortable illumination to players. © 2019 SPIE.

关键词： Light emitting diodes

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Key Challenges and Results in the design of Cubesat Laser Terminals, optical Heads and Coarse Pointing Assemblies

Key Challenges and Results in the Design of Cubesat Laser Te...

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IEEE International Conference on Space optical Systems and Applications (IEEE ICSOS)

作者： Dresscher, M. Korevaar, C. W. van der Valk, N. C. J. de Lange, T. J. Saathof, R. Doelman, N. Crowcombe, W. E. Duque, C. M. de Man, H. Human, J. D. Witvoet, G. van der Heiden, N. den Breeje, R. Kuiper, S. Fritz, E. C. TNO Tech Sci Stieltjesweg 1 NL-2628 CK Delft Netherlands

ISBN: (纸本)9781728105000

The anticipated capacity benefit of optical satellite communications has triggered a cascade of technology developments. In this paper, we present three such technologies, namely;i). A cube satellite laser terminal (CubeCAT), ii). A lower Earth orbit satellite optical head (LEOCAT) and iii). A calibration and verification test bench for coarse pointing assemblies, named pointing test bench (PTB). For these technologies, pointing stability and accuracy are central challenges. For i) and ii), we discuss anticipated effects of the thermal and mechanical disturbances that threaten the optical alignment of the system. We furthermore explain the mitigation of these effects through the system design so that a high optical performance can be maintained. For iii), we discuss the mechanical design challenges, in combination with modelling and calibration procedures for the system. Effective dealing with the three of them in turn enables highly accurate mirror orientation and rotation. design specifications and current status are presented for each system.

关键词： Free space optical communications laser communication terminal laser satellite communications low earth orbit satellite smallsat cubesat optical head coarse-pointing assembly ground-support equipment.

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optical Systems for Large-aperture Phased Laser Array Including Diffractive Optics 20

Optical Systems for Large-aperture Phased Laser Array Includ...

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Conference on current developments in Lens design and optical engineering XX

作者： Erlikhman, Jacob Krogen, Peter Srinivasan, Prashant Hettel, Will Meinhold, Peter Lubin, Philip Univ Calif Santa Barbara Dept Phys Broida Hall Santa Barbara CA 93106 USA

ISBN: (数字)9781510629028

ISBN: (纸本)9781510629028

Directed energy propulsion for interstellar travel has been proposed as an ideal method for reaching appreciable speeds relative to the speed of light: 0.2c. However, the amount of energy required necessitates a large aperture, on the order of kilometers, while mitigation of atmospheric perturbations requires a discretization of the aperture into many individual laser elements. The use of fiber lasers for these elements obligates mode-matching the fiber to the desired 10 cm aperture for a collimated beam. Various collimation systems were designed and compared. A 3-lens system with one achromat and two aspheric lenses, with two of the lenses used as a Keplerian telescope to achieve a system-shortening effect was analyzed. A similar system made with a plano-convex lens replacing the large-aperture aspheric lens with two additional compensating lenses was compared. A single diffractive optic operating at F/8 was likewise considered. The optical performance of these systems was compared, as was the cost-effectiveness. Scalability to millions of elements was required, so cost-per-system was a crucial consideration factor. Possible manufacturing processes for a diffractive system were investigated, and stamping processes for replication were analyzed to determine the possibility of replication of such an optic reliably, cheaply, and with acceptable results.

关键词： Directed energy optical design diffractive optical elements corrective optical elements laser propulsion

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原子芯片的基本原理、关键技术及研究进展

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物理学报 2021年第2期70卷 50-69页

作者：李沫陈飞良罗小嘉杨丽君张健电子科技大学电子科学与工程学院成都611731 中国工程物理研究院电子工程研究所绵阳621999

飞速发展的激光冷却、囚禁与操控中性原子的理论和实验技术不仅促进了人们对微观物质运动规律的认知,而且在精密测量和量子信息领域催生了多项颠覆性的器件与应用.不同于传统复杂庞大的原子光学实验装置,原子芯片通过在硅等基底上制备... 详细信息

飞速发展的激光冷却、囚禁与操控中性原子的理论和实验技术不仅促进了人们对微观物质运动规律的认知,而且在精密测量和量子信息领域催生了多项颠覆性的器件与应用.不同于传统复杂庞大的原子光学实验装置,原子芯片通过在硅等基底上制备的表面微纳结构或器件来精准控制磁场、电场或光场,从而在小尺度、低功耗条件下实现对原子的强束缚与相干操控,被认为是一种稳定、精确、功能及扩展性强大的原子及其量子态片上实验平台,具有广泛且重大的应用价值.本文首先简要回顾了原子芯片的发展历程,然后介绍了基于载流导线的微势阱及微导引实现原子芯片的基本原理,并着重讨论了基于载流导线的原子芯片制备技术、测试方法和集成的全链条关键实现技术.随后,本文综述了各国与原子芯片相关的研究计划布局和主要应用进展,指出原子芯片走向实用面临的挑战性问题,并对其未来发展进行了展望.

关键词：原子芯片原子磁导引冷原子原子光学

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Biomimetics: Nature‐Inspired design and Innovation 1

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2020年

作者： Sandy B. Primrose

ISBN: (数字)9781119683360

ISBN: (纸本)9781119683322

Provides a professional, contemporary, and concise review of the current knowledge and advances in biomimetics This book covers the field of biomimicry, an area of science where researchers look to mimic aspects of plants or animals in order to solve problems in aerospace, shipping, building, electronics, and optics, among others. It presents the latest developments in biomimicry and gives readers sufficient grounding to help them understand the current, and sometimes technically complex, research literature. Different themes are covered throughout and text boxes deal with the relevant physics for readers who may lack this knowledge. Biomimetics: Nature-Inspired design and Innovation examines issues in fluid dynamics such as avoiding sonic booms, reducing train noise, increasing wind turbine efficiency, and more. Next, it looks at optical applications, e.g. how nature generates color without dyes and pigment, and how animals stay cool in desert environments. A chapter on the built environment discusses cooling systems for buildings based on termite mounds; creating self-cleaning paint based on lotus leaves; unobtrusive solar panels based on ivy; and buildings that respond to the environment. Two more sections focus on biomimicry for the creation of smart materials and smart devices. The book finishes with a look at the field’s future over the next decade. Presents each topic in sufficient detail in order to enable the reader to comprehend the original scientific papers Emphasizes those examples of biomimicry that have made it into products Features text boxes that provide information on the relevant physics or engineering principles for biologists who do not have a physics background Covers the scientific literature up to July 2019 Biomimetics: Nature-Inspired design and Innovation is an excellent book for senior undergraduates and post-graduate students in the life sciences, material sciences, and bioengineering. It will also appeal to lay readers with an interest

关键词： cell \u0026 molecular biology

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optical Properties of Materials and Their Applications, Second Edition 2e

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丛书名： Wiley Series in Materials for Electronic & Optoelectronic Applications

2019年

作者： Jai Singh

ISBN: (数字)9781119506003

ISBN: (纸本)9781119506317

Provides a semi-quantitative approach to recent developments in the study of optical properties of condensed matter systems Featuring contributions by noted experts in the field of electronic and optoelectronic materials and photonics, this book looks at the optical properties of materials as well as their physical processes and various classes. Taking a semi-quantitative approach to the subject, it presents a summary of the basic concepts, reviews recent developments in the study of optical properties of materials and offers many examples and applications. optical Properties of Materials and Their Applications, 2nd Edition starts by identifying the processes that should be described in detail and follows with the relevant classes of materials. In addition to featuring four new chapters on optoelectronic properties of organic semiconductors, recent advances in electroluminescence, perovskites, and ellipsometry, the book covers: optical properties of disordered condensed matter and glasses; concept of excitons; photoluminescence, photoinduced changes, and electroluminescence in noncrystalline semiconductors; and photoinduced bond breaking and volume change in chalcogenide glasses. Also included are chapters on: nonlinear optical properties of photonic glasses; kinetics of the persistent photoconductivity in crystalline iii-V semiconductors; and transparent white OLEDs. In addition, readers will learn about excitonic processes in quantum wells; optoelectronic properties and applications of quantum dots; and more. Covers all of the fundamentals and applications of optical properties of materials Includes theory, experimental techniques, and current and developing applications Includes four new chapters on optoelectronic properties of organic semiconductors, recent advances in electroluminescence, perovskites, and ellipsometry Appropriate for materials scientists, chemists, physicists and electrical engineers involved in development of electronic materials Written by in

关键词： electronics optics photonics optical properties materials materials science optoelectronic condensed matter electronic band structure electrical engineering organic semiconductors electroluminescence perovskites ellipsometry

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Freeform Optics design of Primary Lens for Uniform Irradiance Distribution of Concentrator Photovoltaic System 20

Freeform Optics Design of Primary Lens for Uniform Irradianc...

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Conference on current developments in Lens design and optical engineering XX

作者： Pham Thanh Tuan Duy, N. N. Vu Ngoc Hai Shin, Seoyong Myongji Univ Dept Informat & Commun Engn Gyeonggi Do 17058 South Korea Vietnam Acad Sci & Technol Inst Appl Mat Sci Ho Chi Minh City 70072 Vietnam Phenikaa Univ Elect & Elect Engn Hanoi 1000 Vietnam Duy Tan Univ Fac Nat Sci Danang 550000 Vietnam

ISBN: (数字)9781510629028

ISBN: (纸本)9781510629028

In this paper, a primary lens of concentrator photovoltaic (CPV) system is designed by using freeform optics. The designed lens is constructed based on a basic idea of a combination of Fresnel lens and freeform optics, in which the lens is divided into an array of sub-lenses, which are designed using the conservation of optical path length and the edge ray theorem to get uniform irradiance distribution over the receiver. In this design, every sub-lens is designed to guide the direct sunlight over the receiver with uniform irradiance so that the whole of the primary lens will converge uniformly the direct sunlight over the receiver. The structure of the lens is designed firstly by using Matlab program for every sublens. The Matlab data of the designed lens structure is then used to build the three-dimensional (3D) lens in LightTools (TM) software. The ray tracing technique in LightTools (TM) software is used to find out the optimum structure of the freeform lens. Furthermore, the simulation is performed to estimate the efficiency of the lens as a concentrator of a CPV system by using the light source with the sunlight spectrum. The designed lens can achieve high geometrical concentration ratio and uniform irradiance distribution over the receiver. The simulation results show that the lens can easily reach a high concentration ratio (494 times) with uniform irradiance distribution and good optical efficiency (86%).

关键词： Concentrator photovoltaic (CPV) Primary lens Freeform optics Sub-lenses array Uniform irradiance distribution

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Exposure of Restore-L Camera optical Elements to a Simulated Orbital Radiation Environment 20

Exposure of Restore-L Camera Optical Elements to a Simulated...

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Conference on current developments in Lens design and optical engineering XX

作者： Miller, Kevin H. Heaney, James B. Lauenstein, Jean-Marie Brown, Stephen K. O'Connor, Kenneth M. Miller, Sharon K. NASA Goddard Space Flight Ctr 8800 Greenbelt Rd Greenbelt MD 20771 USA SGT KBR 7701 Greenbelt Rd Ste 400 Greenbelt MD 20770 USA NASA Glenn Res Ctr 21000 Brookpark Rd Cleveland OH 44135 USA

ISBN: (数字)9781510629028

ISBN: (纸本)9781510629028

This paper reports on the exposure of visible wavelength camera optical elements to a simulated orbital radiation environment in support of the Restore-L flight project at NASA's Goddard Space Flight Center. Borosilicate glasses with various metal oxide dopants - S-LAL8, S-LAL18, N-SF1, and the polycarbonate material Makrolon GP were exposed to electrons and protons of varying energies. Low energy (E <= 10keV) charged particles were used primarily to assess degradation to the antireflective coatings of the optical elements. High energy (E similar to 1 MeV) charged particles were used to evaluate degradation to the bulk material. Elements of S-LAL18, N-SF1, LaK9G15, and Makrolon GP were exposed to a representative atomic oxygen rich environment. Elements of S-LAL8 and Makrolon GP were exposed to intense ultraviolet radiation. Pre- and post-exposure transmittance measurements were used to quantify the effects on the elements tested in the simulated environment over the 0.3 to 1.2 micron wavelength range. Our measurement results will be discussed in the context of their robustness to the orbital environment and the known chemical constituents of the materials tested.

关键词： Restore-L radiation anti-reflective coating transmittance atomic oxygen ultraviolet

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optical simulation and geometrical optimization of P3HT/GaAs nanowire hybrid solar cells for maximal photocurrent generation via enhanced light absorption

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SOLAR ENERGY 2019年 194卷 848-855页

作者： Prashant, D. V. Samajdar, D. P. Sharma, Dheeraj Indian Inst Informat Technol Design & Mfg Dept ECE Jabalpur 482005 Madhya Pradesh India

The implications of using the combination of inorganic and organic materials in the active layer of solar cells have motivated researchers to find a new pathway for flexible, low cost, and highly efficient future generation solar cells. iii-V material based nanowires (NWs) with subwavelength scale diameters have shown excellent light harvesting and charge transport properties and can be easily combined with organic polymer materials and thin substrates to design hybrid solar cells (HSCs). To obtain optimum design requirements for GaAs nanowire array (NWA) HSCs, an optical simulation of poly(3-hexylthiophene) P3HT/GaAs (NWA) hybrid solar cell is investigated using finite-difference-time-domain (FDTD) method. In comparison to planar substrate, P3HT coated NWA have shown superior optical properties owing to its intrinsic anti-reflection, broad absorption spectra, and efficient excitation of resonance modes. A steady improvement in light absorption of P3HT/GaAs NWA HSCs is observed as the polymer coating thickness increased up to a certain limit and beyond which there is a significant degradation in the exciton generation. The geometrical parameters like diameter (D) of NW and filling ratio or periodicity are also optimized to achieve superior light absorption and maximum short circuit current density (J(sc)). Under AM1.5G illumination, maximum photocurrent obtained for optimized structure with conformal coating of P3HT is almost 12% and 15% higher than its fully infiltrated and uncoated counterparts respectively

关键词： GaAs NWs P3HT FDTD Absorption Hybrid solar cells

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Wide Band Transimpedance Amplifier using Class AB FVF 3

Wide Band Transimpedance Amplifier using Class AB FVF

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3rd International Conference on Recent developments in Control, Automation and Power engineering (RDCAPE)

作者： Singh, Nidhi Niranjan, Vandana Indira Gandhi Delhi Tech Univ Women Dept Elect & Commun Engn New Delhi India

ISBN: (纸本)9781728120683

CMOS technologies have swiftly ameliorated across the past few years. To meet the demand of high performance applications like compact disc players, high definition television (HDTV), radar, medical imaging etc., this employs info conversion system for processing at later stages. Accuracy is highly desirable in many functional systems like optical communication, military surveillance etc. In optical communication system, transimpedance amplifier (TIA) is the fundamental part of optical receiver which is required to convert the low level current signal from the photodiode to an operable output voltage for further processing. Here in this paper, we propose a CMOS TIA using class-AB flipped voltage follower having less output resistance. Simulation results of the proposed circuit in 0.18 mu m technology depicts that the bandwidth and the transimpedance gain obtained are increased by 3.3 times and 1.03 times respectively.

关键词： Flipped voltage follower (FVF) optical Receiver Transimpedance amplifier (TIA) low voltage low power design

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