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Simultaneous Multiple Surfaces method applied to infrared lenses 23

Simultaneous Multiple Surfaces method applied to infrared le...

Conference on current developments in Lens design and optical engineering XXIII Part of SPIE Optics and Photonics Conference

作者： Mayeur, T. volatier, J. B. Druart, G. Tartas, E. Durand, A. Cau, F. Off Natl Etud & Rech Aerosp 6 Chemin Vauve Granges F-91120 Palaiseau France Lynred 364 Route Valence F-38113 Veurey Voroize France Safran Elect & Def 100 Ave Paris F-91300 Massy France

ISBN: (纸本)9781510654198;9781510654181

In optical design, the designer's experience is critical. Indeed, an experienced optical designer will often choose a better starting point for optimization than an inexperienced one. Most of the time, lens design software use a local optimization algorithm, which is why the starting point is so important to get an excellent optical system. We present here an alternative to the classical optical design method and a solution to reduce the impact of the designer's experience. Our alternative couples the Simultaneous Multiple Surfaces (SMS) method, introduced by Benitez and Minano with optimization in Zemax OpticStudio. The SMS method is a direct construction method of optical systems without optical aberrations for as many field points as the system contains surfaces. This method can deal with both aspheric and freeform optical systems depending on the dimension of the method implemented. Our implementation of the SMS method can design optical systems with three surfaces. We use the SMS method to define a freeform system with an F-number of 0.85. Then, we use this fast freeform system as a starting point to perform further optimization in Zemax OpticStudio. Finally, we achieve to design two diffraction-limited freeform systems, one over a square field of view of +/- 30 degrees and another over a rectangular field of view of +/- 33 degrees x +/- 26 degrees.

关键词： Simultaneous Multiple Surfaces freeform surfaces Cartesian oval automated method optical design

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design and simulation of AlGaAs Curved Mirror vertical Cavity Surface Emitting Laser 29

Design and simulation of AlGaAs Curved Mirror Vertical Cavit...

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vertical-Cavity Surface-Emitting Lasers XXIX 2025

作者： Nashed, A.I. Lestrade, Michel Li, Z.Q. Li, Z.M. Simon Crosslight Software Inc. 230-3410 Lougheed Hwy VancouverBCV5M 2A4 Canada

ISBN: (数字)9781510685178

ISBN: (纸本)9781510685161

This paper presents the design and simulation of an AlGaAs-based vertical Cavity Surface Emitting Laser (vCSEL) with a curved bottom Distributed Bragg Reflector (DBR), operating at 830 nm. The curved mirror enhances mode confinement, reducing threshold current to 0.8 mA and improving output power to 5mW at 5mA bias, outperforming flat mirror designs. Dynamic simulations under 1 GHz modulation confirm excellent high-speed performance. These results demonstrate the potential of curved mirror vCSELs for compact, efficient, and high-frequency optical applications. © 2025 SPIE.

关键词： Surface emitting lasers

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design of a low-temperature drift voltage reference based on parasitic capacitance startup 7

Design of a low-temperature drift voltage reference based on...

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7th International Conference on Advanced Electronic Materials, Computers, and Software engineering, AEMCSE 2024

作者： Zhou, Lu College of Wealth Management Ningbo University of Finance & Economics Zhejiang China

ISBN: (纸本)9781510681866

To enhance the performance of the PMU, a voltage reference based on a voltage bandgap has been proposed. During the power-on process, the startup circuit is activated due to parasitic capacitance coupling. After the power-on process is completed, the startup circuit self-turns off to reduce power consumption. Subsequently, a high-order compensation circuit is designed to generate a current with only constant and high-order temperature terms, compensating for the temperature coefficient of the voltage bandgap. An RC filter is then added to the output to improve the power supply rejection ratio in the high-frequency range. To further reduce the power consumption of the voltage bandgap, almost all MOS transistors are operated in the subthreshold region, achieving a decrease in static current consumption. Circuit design and simulation were completed based on the TSMC 0.18 μm CMOS process. The results indicated that at a supply voltage of 1.8 v, the bandgap output was 1.232 v;within the temperature range of -40 ℃ to 140 ℃, the temperature coefficient was 4.8×10-6 ℃-1;with the addition of the RC filter, the power supply rejection ratio at high frequency was -73 dB @ 10 MHz;furthermore, the static current of the entire bandgap was only 3.7 μA. © 2024 SPIE.

关键词： CMOS integrated circuits

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Applications of bio-derived/bio-inspired materials in the field of interfacial solar steam generation

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Nano Research 2022年第4期15卷 3122-3142页

作者： Yang Geng Kai Jiao Xu Liu Peijin Ying Omololu Odunmbaku Yaoxin Zhang Swee Ching Tan Ling Li Wei Zhang Meng Li MOE Key Laboratory of Low-grade Energy Utilization Technologies and Systems CQU-NUS Renewable Energy Materials&Devices Joint LaboratorySchool of Energy&Power EngineeringChongqing UniversityChongqing 400044China Key Laboratory of Thermo-Fluid Science and Engineering of MOE School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049China Department of Materials Science and Engineering CQU-NUS Renewable Energy Materials&Devices Joint LaboratoryNational University of SingaporeSingapore 117573Singapore Department of Mechanical Engineering Virginia Polytechnic Institute and State UniversityBlacksburgVA 24061USA Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

Interfacial solar steam generation(ISSG)system has attracted extensive attention as a sustainable desalination technology because of its cost efficiency and zero fossil-energy *** at optimizing the desalination properties,materials and system design have been the current research ***,many novel bio-derived/bio-inspired design strategies were proposed owing to their highly efficient structures inherited from nature,which were fine-tuned over eons of evolution,as well as their low cost and ease of *** this review,we are going to systematically report recent progress of various bio-derived/bio-inspired strategies in terms of optical design,wetting,thermal management,and overall system design,presenting an overview of the current challenges of bio-inspired materials in ISSG system and other application *** article is intended to provide a comprehensive review of recent developments about bio-derived/bio-inspired materials in ISSG system and conclude with suggestions regarding further research directions for performance enhancement through design of bio-derived/bio-inspired materials.

关键词： interfacial solar steam generation bio-derived materials bio-inspired materials solar-thermal conversion thermal management

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design of projection-based augmented reality system using holographic screen display 23

Design of projection-based augmented reality system using ho...

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Conference on current developments in Lens design and optical engineering XXIII Part of SPIE Optics and Photonics Conference

作者： Nishikawa, Jun Nakamura, Tomoharu Sony Grp Corp R&D Ctr Atsugi TEC 4-14-1 Asahi Cho Atsugi Kanagawa 2430014 Japan

ISBN: (纸本)9781510654198;9781510654181

Holographic display elements (HOEs) with a high diffraction efficiency and size enlargement have been developed since 2019. To achieve high brightness and low haze, unprecedented optical systems have been proposed with a uniform chief ray angle of 0 degrees in the x-section and 70 degrees in the y-section of the HOEs. A 360 degrees cylindrical holographic screen display (CHSD) was obtained by providing a large tilt to the surface shape near the optical axis. This was done using a first-order odd aspherical coefficient for the light flux from a refractive optical system (RO). A flat holographic screen display (FHSD) is a compact, high-performance display that uses three decentered and tilted freeform mirrors to route light flux from the RO in a ball-like form. Prototyping also proposes the possibility of an augmented reality system that takes advantage of the high transparency. The design for further miniaturization while maintaining optical performance was also discussed, in which the size of the first mirror was reduced by reducing the half-field angle of the RO to approximately 6 degrees. Furthermore, by increasing the negative power of the second mirror, the small size could be maintained The size of the last mirror was dependent on the screen size and could not be reduced. By laying down the posture of this mirror, we were able to halve the size reduction in the vertical direction. In this paper, lens designs for CHSDs and FHSDs are reported. The potential of this display is also discussed.

关键词： Holographic optical elements augmented reality display freeform mirror projection lens lens design

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Low-power off-chip capacitor-free LDO design with high transient response 2

Low-power off-chip capacitor-free LDO design with high trans...

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2nd International Conference on Electrical, Electronics, and Information engineering, EEIE 2023

作者： Wu, Haoran Yin, Jiayu Huang, Xindong Chen, Chengying Xiamen University of Technology No. 600 Polytechnic Road Houxi Town Jimei District Xiamen China

ISBN: (纸本)9781510672840

To reduce the area occupied by the low dropout regulator (LDO) in the whole chip system and to current consumption in standby state, this paper proposes a new structure using a diode-connected PMOS as a load resistor, which optimizes the area of the chip under the premise of guaranteeing the performance. The circuit is realized with UMC 28nm 1p9m process. The simulation results show that it can stably output a voltage of 1.197v under an input voltage of 2.5-3.6v, and its current operation range is 100μA-20mA with a transient response time of ≤0.5μs, a quiescent current of 9μA, and a phase margin of ≥77°. © 2024 SPIE.

关键词： Transient analysis

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Fault Detection of Distributed Power Distribution Network Based on Grey Wolf pack Algorithm

Fault Detection of Distributed Power Distribution Network Ba...

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2024 International Conference Optoelectronic Information and optical engineering, OIOE 2024

作者： Li, Yuqing Luo, Jinman Wang, Haiji Dongguan Power Supply Bureau Guangdong Power Grid Corporation Guangdong Dongguan China China Energy Construction Group Guangdong Electric Power Design and Research Institute Co. Ltd. Guangdong Guangzhou China

ISBN: (数字)9781510688209

ISBN: (纸本)9781510688193

The integration of distributed power supply into the distribution network is an important trend in the development of the current new power system. In view of the problem that the system can not quickly and accurately obtain the fault type and locate the location of the fault when the current distributed power distribution network fails. Introduce a detection method to optimize the current fault analysis system of distribution network based on the grey Wolf pack algorithm (Grey Wolf Optimization, GWO), and optimize the fault detection algorithm based on the optimization of distribution network structure. In addition, a complete analytical model of complete fault information such as medium calculation, misoperation and action is constructed to improve the analytical model of detecting complex fault situations in the distribution network. Through example analysis, the effectiveness of the fault detection model of distributed power distribution network based on gray Wolf swarm algorithm is verified, reducing the probability of fault miscalculation of distribution network to a certain extent, and solving the problem of low accuracy and slow speed of distribution network fault detection in the traditional algorithm. © 2025 SPIE.

关键词： Power distribution faults

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current developments in Lens design and optical engineering XXI

Current Developments in Lens Design and Optical Engineering ...

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current developments in Lens design and optical engineering XXI 2020

ISBN: (纸本)9781510637702

The proceedings contain 14 papers. The topics discussed include: ultrashort throw lenses with catadioptric relay suitable for flat and curved screens;light field displays for near eye vR and AR;wide angle lens with improved relative illumination characteristics;optimization of a mobile phone camera for as-built performance;inverse designed flat optics with multilevel diffractive lenses;optical design of triple-mode seeker;comparison of passive athermalization results of LWIR optical designs utilizing different infrared optical materials;and design of an anastigmatic three-mirror telescope using freeform surfaces.

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design and Analysis of optical Wireless Communication Systems 4

Design and Analysis of Optical Wireless Communication System...

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4th International Conference on Smart Electronics and Communication, ICOSEC 2023

作者： Kannan, K. Jagadesan, A. Karthika, G. Pokhariya, Hemant Singh Kaliappan, S. Kanimozhi, K.v. R.M.K. College of Engineering and Technology Department of Electronics and Communication Engineering Tamil Nadu Chennai601206 India R.M.K Engineering College Department of Physics Tamil Nadu Kavaraipettai601206 India R.M.D. Engineering College Department of Electronics and Communication Engineering Tamil Nadu Kavaraipettai601206 India Graphic Era Deemed to Be University Department of Computer Science and Engineering Uttarakhand Dehradun248002 India Lovely Professional University Division of Research and Development Punjab Phagwara144411 India Saveetha School of Engineering Saveetha Institute of Medical and Technical Sciences Department of Computer Science and Engineering Tamil Nadu Chennai602105 India

ISBN: (纸本)9798350300888

The design and implementation of Underwater Wireless optical Communication (UWOC) provide important scientific problems. UWOC has the ability to transmit data at a high pace across long distances. This essay makes an effort to concentrate on the complexity of real-world applications and unresolved problems in UWOC systems. The key developments and advancements in the subject, modelling methods, and connection design difficulties are outlined. The goal of this study is to provide recommendations for a practical and trustworthy UWOC design with enhanced performance. Finally, a summary of the key aspects is provided to aid in future UWOC study. © 2023 IEEE.

关键词： Light emitting diodes

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vLC positioning in low data rate for v2v communication 2024

VLC positioning in low data rate for V2V communication

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12th Euro-American Conference on Telematics and Information Systems, EATIS 2024

作者： Giraldo, Luis Miguel Soler, Joaquin Perez Botella-Mascarell, Carmen Juan, vicent Girbes varea, Sandra Roger Torres, Julio Martos Olcina, Raimundo Garcia Electronical Engineering Department Universitat de València Burjassot Valencia46100 Spain Computer Science Department Informatics Department Universitat de València Burjassot Valencia46100 Spain

ISBN: (纸本)9798400717338

The creation and implementation of a system that bridges visible light communication (vLC) with selected identifiers, envisioned as informational beacons, are outlined. This system is adept at controlling LED panels and orchestrating communication between LED lights and the receiving unit, laying the groundwork for vehicle-to-vehicle (v2v) communication systems tailored for precise positioning. The design and assessment of test-bed requirements cater to the anticipation of future v2v optical wireless communication scenarios. Through analysis, it is demonstrated that commercial outdoor lighting can be effectively utilized for v2v positioning, capable of operating under daylight with a data transmission rate of 100 Kbps. Crucially, the system's ability to accurately detect positioning beacons facilitates the localization of vehicles within designated areas of interest, paving the way for the advancement of v2v communication technologies. This comprehensive approach not only validates the feasibility of using vLC for vehicle positioning but also sets a precedent for future developments in v2v communication systems. © 2024 Owner/Author.

关键词： optical communication

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