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

作者： Santiago Alvarado, Agustin Cruz Felix, Angel S. Santiago Gomez, Stephanie L. Ruiz Zavala, Soledad Osorio Garcia, Adelita Iturbide Jimenez, Fernando Univ Tecnol Mixteca Carretera Acatlima Km 2-5 Huajuapan De Leon 69000 Oaxaca Mexico

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

The main characteristic of adaptive lenses is to change their shape, and consequently their focal length, by modifying their physical parameters. On the other hand, Fresnel lenses have such features as large aperture, short focal length, they are slim and reduced in size. These kind of lenses have become very popular due to their applications, such as in compound eyes, optical communication systems, photolithography, imaging systems, etc. Nowadays, several kinds of tunable lenses exist such as those made with dielectric materials, lenses that change their focal length by varying the refractive index of the material, liquid lenses composed by elastic membranes and solid elastic lenses. In this work, we present the design, simulation of the mechanical behavior using Finite Element Method (FEM) and cost analysis of an Adaptive Fresnel Lens made of an elastic material, together with a mechanical mounting system. Our study considered the use of design thinking methodology to obtain the best optical design at minimal cost. Analysis, results and future applications are presented.

关键词： Adaptive Fresnel lens design Thinking optical design

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Comparison and perspective of conventional and LED lighting for photobiology and industry applications

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ENvIRONMENTAL AND EXPERIMENTAL BOTANY 2020年第0期171卷 103953-000页

作者： Wu, Bo-Sen Hitti, Yasmeen MacPherson, Sarah Orsat, valerie Lefsrud, Mark G. McGill Univ Dept Bioresource Engn 21111 Lakeshore Rd Ste Anne De Bellevue PQ H9X 3V9 Canada

A vast interest in plant photobiological responses is growing in both academia and commercial sectors, due to rapid developments in electrical lighting technology. Each lighting technology has its own advantages and corresponding applications, as well as disadvantages. The advantages of light emitting diodes (LEDs) have been reviewed extensively, supporting them as suitable lighting sources to investigate plant photobiological responses. However, conventional lighting sources possess some properties that cannot be met by LEDs. In this work, we provide a different perspective when considering electrical lighting system applications in plant photobiology, including wavelength availability, longevity, spectral reliability, and light uniformity. optical and electrical components are addressed with respect to both laboratory use and greenhouse operations. The latest research findings on how different lighting sources (spectral compositions) influence the physiology of plants are presented, and current challenges for LED technology with respect to plant photobiology are discussed. Electrical lighting systems benefit the plant photobiology field in numerous ways, but comprehensive knowledge of external environment factors is required, rather than choosing the latest lighting technology.

关键词： Electrical lighting HPS LEDs Photobiology Reliability

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高稳定性快速响应的无片外电容LDO设计

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微电子学与计算机 2024年第7期41卷 119-126页

作者：谢晋李景虎吴思妮陈启彬涂瑞泳罗志聪福建农林大学机电工程学院福建福州350002 厦门亿芯源半导体科技有限公司福建厦门361009 福建农林大学计算机与信息学院福建福州350002 福建省农业信息感知技术重点实验室福建福州350002

针对光通信集成电路及片上系统的电源与电路之间相互干扰的问题,基于TSMC 65 nm CMOS工艺,设计了一种高稳定性、快速响应的无片外电容低压差线性稳压器(Capacitor-Less Low Dropout Regulator,CL-LDO)。LDO电路包括带隙基准模块、推挽... 详细信息

针对光通信集成电路及片上系统的电源与电路之间相互干扰的问题,基于TSMC 65 nm CMOS工艺,设计了一种高稳定性、快速响应的无片外电容低压差线性稳压器(Capacitor-Less Low Dropout Regulator,CL-LDO)。LDO电路包括带隙基准模块、推挽误差放大器、电源抑制比(Power Supply Rejection,PSR)增强电路和尖峰抑制电路。推挽误差放大器为共栅极输入,有效降低了输出阻抗。放大器交叉耦合输入的方式显著提升了功率管摆率,内部添加拓补结构解决了环路增益过低及对称性差的问题,采用密勒补偿实现了0~100 pF全负载电容条件下系统稳定。主环路结合尖峰抑制电路改善瞬态性能,PSR增强电路产生可修调的负电容消除了功率管栅端产生的电源纹波,有效提升了LDO中频段电源抑制比。仿真结果表明,负载电流在0~100 mA内,该LDO的上冲电压和下冲电压分别为58 mv和89 mv,最小恢复时间为1.2μs,全负载范围内最差的相位裕度为64°,空载状态下的电源抑制比为99.2 dB@10 kHz,在不同工艺角下最差的负载调整率和线性调整率分别为0.016 mv/mA和5.1 mv/v。

关键词：无片外电容高稳定性快速响应 LDO 推挽放大器

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Field-of-view enhancement for commercially available active imaging camera using time-of-flight technology 19

Field-of-view enhancement for commercially available active ...

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

作者： Poulin-Girard, Anne-Sophie Smith, Michael Gagnon, Mathieu Legault, Marc-Antoine Thibault, Simon Univ Laval Ctr Opt Photon & Lasers 2375 Rue Terrasse Quebec City PQ G1V 0A6 Canada Innovat Vehicle Inst 25 Boul Maisonneuve St Jerome PQ J5L 0A1 Canada

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

Active imaging techniques have been, and will remain relevant as an integral part of the sensor network needed in mobile robotics navigation, most commonly with the use of LiDARs. For close range applications, time-of-flight (TOF) cameras are an alternative to more expensive LiDARs. The Kinect v2 (Kinect for XboxOne) has been used frequently as a range imaging camera in machine vision research because of its low cost and good performance. For mobile robotics applications moving at low speed, a larger field of view than the original (70 degrees X 60 degrees) would be desirable to increase awareness of the surroundings, and also detect other moving objects in the trajectory. Our main goal is therefore to increase the Kinect v2 field of view while keeping its main feature of depth measurements. A simple but effective solution consists in using a conversion lens to increase the ray collection angle before the rays enter the IR camera. Depth measurements remain possible from each pixel using TOF with the Kinect v2 modulated signal, provided the field of illumination matches the field of view. A trade-off has to be made between accuracy of depth measurement, optical performance and field of view/illumination enhancement. Therefore, we modified a Kinect v2 to characterize its optical performances and evaluate its relevancy for applications requiring accurate knowledge of the 3D surroundings. A field of view improvement of the Kinect v2 and other similar TOF cameras could offer an alternative at minimal cost for depth measurements in machine vision, specifically in mobile robotics research where object detection and mapping tasks are frequently carried out.

关键词： Active imaging optical system mobile robotics depth camera range imaging time of flight wide angle machine vision

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Coronary artery segmentation from intravascular optical coherence tomography using deep capsules

arXiv

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arXiv 2020年

作者： Balaji, Arjun Kelsey, Lachlan J. Majeed, Kamran Schultz, Carl J. Doyle, Barry J. Vascular Engineering Laboratory Harry Perkins Institute of Medical Research QEII Medical Centre Nedlands and Centre for Medical Research The University of Western Australia Perth Australia School of Engineering The University of Western Australia Perth Australia Department of Cardiology Royal Perth Hospital Perth Australia School of Medicine The University of Western Australia Perth Australia University of Ottawa Heart Institute OttawaON Canada Australian Research Council Centre for Personalised Therapeutics Technologies Australia British Heart Foundation Centre for Cardiovascular Science The University of Edinburgh United Kingdom

The segmentation and analysis of coronary arteries from intravascular optical coherence tomography (IvOCT) is an important aspect of diagnosing and managing coronary artery disease. current image processing methods are hindered by the time needed to generate expert-labelled datasets and the potential for bias during the analysis. Therefore, automated, robust, unbiased and timely geometry extraction from IvOCT, using image processing, would be beneficial to clinicians. With clinical application in mind, we aim to develop a model with a small memory footprint that is fast at inference time without sacrificing segmentation quality. Using a large IvOCT dataset of 12,011 expert-labelled images from 22 patients, we construct a new deep learning method based on capsules which automatically produces lumen segmentations. Our dataset contains images with both blood and light artefacts (22.8%), as well as metallic (23.1%) and bioresorbable stents (2.5%). We split the dataset into a training (70%), validation (20%) and test (10%) set and rigorously investigate design variations with respect to upsampling regimes and input selection. We show that our developments lead to a model, DeepCap, that is on par with state-of-the-art machine learning methods in terms of segmentation quality and robustness, while using as little as 12% of the parameters. This enables DeepCap to have per image inference times up to 70% faster on GPU and up to 95% faster on CPU compared to other state-of-the-art models. DeepCap is a robust automated segmentation tool that can aid clinicians to extract unbiased geometrical data from IvOCT. © 2020, CC BY.

关键词： optical tomography

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大面积三角形探测光幕灵敏度空域分布分析

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应用光学 2021年第6期42卷 956-962页

作者：段晨曦倪晋平李敬陈瑞崔长青刘洋西安工业大学光电工程学院陕西西安710021 中国兵器装备集团有限公司黑龙江北方工具有限公司黑龙江牡丹江157000 中国兵器工业集团有限公司内蒙古北方重工业集团有限公司内蒙古包头014030

分体式探测光幕实现室内靶道弹丸初速测试时,探测光幕的灵敏度直接影响初速测量的精度。研究了线光源配接镜头式接收装置组成大面积三角形探测光幕的灵敏度分布,考虑光学镜头离轴效应和线光源随距离衰减现象,将探测光幕内不同位置处光... 详细信息

分体式探测光幕实现室内靶道弹丸初速测试时,探测光幕的灵敏度直接影响初速测量的精度。研究了线光源配接镜头式接收装置组成大面积三角形探测光幕的灵敏度分布,考虑光学镜头离轴效应和线光源随距离衰减现象,将探测光幕内不同位置处光照度等效到线光源处,假设光幕厚度均匀,弹长始终大于幕厚,弹丸遮挡探测光幕所形成的面积与当前区域光幕截面积之比等效为弹径与当前位置处光幕宽度之比。在4.8 m×2.4 m三角形探测光幕上进行理论仿真与实弹试验验证,仿真分析与实弹试验结果一致,靠近镜头处灵敏度大,远离镜头处灵敏度小,且关键探测区域内模拟电压幅值标准差为0.05 v,均匀性符合测试要求。研究结果可为三角形探测光幕的工程设计提供参考。

关键词：大面积探测光幕距离衰减离轴效应空域灵敏度分布

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Side-Chain engineering of Nonfullerene Acceptors for Near-Infrared Organic Photodetectors and Photovoltaics

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ACS ENERGY LETTERS 2019年第6期4卷 1401-1409页

作者： Lee, Jaewon Ko, Seo-Jin Lee, Hansol Huang, Jianfei Zhu, Ziyue Seifrid, Martin vollbrecht, Joachim Brus, viktor v. Karki, Akchheta Wang, Hengbin Cho, Kilwon Thuc-Quyen Nguyen Bazan, Guillermo C. Univ Calif Santa Barbara Dept Chem & Biochem Ctr Polymers & Organ Solids Santa Barbara CA 93106 USA Pohang Univ Sci & Technol Dept Chem Engn Ctr Adv Soft Elect Pohang 37673 South Korea Univ Calif Santa Barbara Mat Res Lab Mitsubishi Chem Ctr Adv Mat Santa Barbara CA 93106 USA KRICT Div Adv Mat Daejeon 34114 South Korea

Narrow bandgap n-type molecular semiconductors are relevant as key materials components for the fabrication nearinfrared organic solar cells (OSCs) and organic photodetectors (OPDs). We thus designed nearly isostructural nonfullerene electron acceptors, except for the choice of solubilizing units, which absorb from 600 to 1100 nm. Specific molecules include CTIC-4F, CO1-4F, and COTIC-4F, whose optical bandgaps are 1.3, 1.2, and 1.1 ev, respectively. Modulation of intramolecular charge transfer characteristics was achieved by replacing alkoxy groups with alkyl groups on thiophene spacers that connect an electron-rich cyclopentadithiophene core to peripheral electronpoor fragments. OSCs incorporating CTIC-4F and CO1-4F with PTB7-Th achieve power conversion efficiencies of over 10% with short-circuit current densities as high as similar to 25 ***(-2). The same blends achieve OPD responsivities of 0.52 A.W-1 at similar to 920 nm. These findings highlight outstanding opportunities to tune further molecular design so that OPDs may ultimately compete with their silicon counterparts.

关键词： Sensors Absorption Solar cells Energy levels Recombination

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Experimental study of power-limiting factors of 1.1 μm range edge-emitting lasers based on InGaAs/GaAs quantum well-dot nanostructures 6

Experimental study of power-limiting factors of 1.1 μm rang...

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6th International School and Conference on Optoelectronics, Photonics, engineering and Nanostructures, SPbOPEN 2019

作者： Serin, A.A. Payusov, A.S. Kornyshov, G.O. Shernyakov, Yu.M. Mintairov, S.A. Kalyuzhnyy, N.A. Kulagina, M.M. Zhukov, A.E. Gordeev, N.Yu. Maximov, M.v. Ioffe Institute 26 Polytechnicheskaya St Petersburg194021 Russia St. Petersburg Academic University 8/3 Khlopina St Petersburg194021 Russia

We present a study of high-power characteristics of edge-emitting lasers based on quantum well-dots (QWD) in a pulsed regime. QWD-based lasers with 2 and 5 active layers emitting at ∼1.1 μm provided maximal optical power of 39 W limited by the pulse current source available. We have investigated the lasing spectra and shown that under the injection current above 20 kA/cm2 the active region overheats approximately by 0.5°C per 1 kA/cm2 during 100 ns current pulse. The active region overheating correlates well with the reducing of the differential efficiency of our devices. We believe that maximal pulse optical power of the QWD-based lasers is limited mainly by our laser wafer design rather than by the QWD active media properties. © Published under licence by IOP Publishing Ltd.

关键词： Semiconductor quantum wells

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design of ergonomic handpieces for a CO₂ laser system for surgical and cosmetological applications 19

Design of ergonomic handpieces for a CO<sub>2</sub> laser sy...

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

作者： Zavatskaia, Kseniia voznesenskaya, Anna ITMO Univ Dept Appl & Comp Opt St Petersburg Russia

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

The CO2 laser systems are widely used for different specialised surgery types and cosmetological procedures. The market is filled with various offers regarding the systems, however, every manufacturer supplies a very limited range of handpieces with the equipment. Thus, the work of surgeon or a medical worker is complicated by the discrepancy of a handpiece with the ergonomic/ technical requirements for a specific procedure. It may result in negative consequences of the procedure itself or a choice not in favor of laser technologies. The work presents the design of optical system and construction of specialised handpieces for CO2 laser system based on the discussion with medical workers of several hospitals that directly interact with the equipment and the technical requirements of medical procedures.

关键词： CO2 laser handpiece laser surgery optical design

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optical coatings for the optical concentrator with the prism film 19

Optical coatings for the optical concentrator with the prism...

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

作者： Jaing, Cheng-Chung Wan, Wei-Li Yang, Pao-Keng Ying, Shang-Ping Chen, Bing-Mau Minghsin Univ Sci & Technol Dept Optoelect Syst Engn 1 Xinxing Rd Hsinchu 30401 Taiwan

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

Effects of a coating combination, a prism film and a phosphor layer on the short current of the solar cell in the optical solar concentrator and the illuminance of the sunlight passing through the samples were investigated. The optical solar concentrator was a 50 mm x 50 mm x 5 mm B270 thick glass with its sides connected by a solar cell. The prismatic structure of the prism film had a period of 50 mu m. A phosphor Y560 having an absorption band of 390 nm to 500 nm and emitting from 490 nm to 700 nm was prepared. Six coating combinations applied in this study were composed of optical filters and glass. The optical filters included infrared cut-off, magenta, red, green and blue filters. The deflection angle was between 31 and 33 degrees when the incident sunlight passed through the prism film. The short current of the solar cell in the optical solar concentrator with the prism film, the coating combination and the phosphor layer was largest in this study. Experimental results show that the coating is more suitable for enhancing the short current than the phosphor layer in the optical solar concentrator with the prism film. And the phosphor layer can increase the illuminance of the sunlight passing through the samples due to the human eye sensitivity.

关键词： optical concentrator coating prism film phosphor layer short current illuminance optical filter solar cell

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