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Conference on current developments in Lens design and optical engineering XVII

作者： Diaz-Gonzalez, G. Santiago-Alvarado, A. Munoz-Lopez, J. Juarez-Salazar, R. Cruz-Felix, A. S. Jimenez-Barriga, N. Univ Tecnol Mixteca Carretera Acatlima Km 2-5 Mexico City 69000 DF Mexico Inst Nacl Astrofis Optic Elect Luis Enrique Erro 1 Puebla 72840 Mexico Inst Politecn Nacl CONACYT CITEDI Ave Inst Politecn Nacl 1310 Tijuana 22435 BC Mexico

ISBN: (数字)9781510602861

ISBN: (纸本)9781510602854;9781510602861

Tunable lenses have become very popular elements due their capacity of change their focal length by only modifying their shape. This characteristic is very useful in different applications in the field of optics. The development of tunable lenses consists on several phases: first, to find a suitable material, second, to obtain an optimal analysis and design, and third, to find the way to change the lens shape and characterization. In this work we present the characterization of a tunable lens, formed by spherical profiled elastic membranes and a liquid medium between them. The proposed liquid-filled tunable has a design such that the spherical aberration is the least to different focus. The development of an optomechanical system to change the lens shape is presented.

关键词： Tunable lens liquid filled lens opto-mechanical design

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Proceedings of SPIE - The International Society for optical engineering

Proceedings of SPIE - The International Society for Optical ...

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current developments in Lens design and optical engineering XVII

ISBN: (纸本)9781510602861

The proceedings contain 35 papers. The topics discussed include: some methods for determining the limit of potential image quality of optical systems of various complexities using the database;optical design of an ultrashort throw ratio projector with two freeform mirrors;reduce volume of head-up display by image stitching;optical performance of a PDMS tunable lens with automatically controlled applied stress;fabrication of focus-tunable liquid crystal microlens array with spherical electrode;characterization of a tunable liquid-filled lens with minimum spherical aberration;design of a radiance meter with predicted size of source and distance effects;formation of the color image based on the vidicon TV camera;AND efficient 3M PBS enhancing miniature projection optics.

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design investigation of a cost-effective dual-band (MWIR/LWIR) and a wide band optically athermalized application 17

Design investigation of a cost-effective dual-band (MWIR/LWI...

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Conference on current developments in Lens design and optical engineering XVII

作者： Ding, Fujian Washer, Joe Morgen, Daniel ISP OPT 50 S Buckhout St Irvington NY 10533 USA

ISBN: (数字)9781510602861

ISBN: (纸本)9781510602854;9781510602861

Dual-band and wide-band lenses covering both the MWIR and LWIR spectral bands are increasingly needed as dual-band MWIR/LWIR detectors have become prevalent and broadband applications have expanded. currently in dual-band /wide-band applications, the use of more than three elements per lens group and the use of chalcogenide glass is common. This results in expensive systems. Also, many chalcogenides are available only in small diameters, which is a problem for large aperture broadband lenses. In this paper an investigation of cost-effective designs for dual-band MWIR/LWIR lens using only widely available IR materials, specifically Ge, ZnSe and ZnS were performed. An athermalized dual-band MWIR/LWIR using these three materials is presented. The performance analysis of this lens shows that this design form with these three common IR materials works well in certain applications. The required large size blanks of these materials can be easily obtained. Traditional chromatic aberration correction without diffraction for either wide-band or dual-band application was employed. In addition, the methods of harmonic diffraction for dual-band applications, especially with one narrow band, were used for two different presented designs.

关键词： IR Imaging IR Wide-band Lens Dual-band Lens Athermalization Chromatic Aberration Correction Harmonic diffraction

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Low power and high speed CMOS current comparators

Low power and high speed CMOS current comparators

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2016 International Conference on Advances in Electrical, Electronic and Systems engineering, ICAEES 2016

作者： Restu, Wan Irma Idayu Nasir, Binti Wan Mohd Reaz, Md. Mamun Bin Ibne Dept. of Electrical Electronics and System Engineering Universiti Kebangsaan Malaysia Bangi Selangor Malaysia

ISBN: (纸本)9781509028894

Over the past few decades, a current comparator in CMOS technology has been used in the wide range of application in analogue, multiple-valued logic (MVL) circuits and other electronic products. current comparator usually used in analog to digital (ADC) conversion and any sensing detector or devices. The design of comparator has been successfully performed by applying several techniques and approach to improve the performance. This paper presents an overview of evolutionary CMOS current comparator, describing the contributions in low power and high speed according a collection of existing proposal. Various schemes and information have been taken to help researcher who will continue work on significant further developments. Lastly, some consideration of recent architectures such as power consumption and speed in current comparator are presented. © 2016 IEEE.

关键词： Comparators (optical)

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Millimeter-wave receivers for wireless communications. 1

Millimeter-wave receivers for wireless communications. 1

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作者： Overmiller, Brock Morgan. University of Delaware.bElectrical and Computer Engineering.

学位级别：M.S.

The modern communications environment is becoming an increasingly crowded place, resulting in rapidly increasing demands on current technology. Military and civilian operations require the ability to locate and decode all communication signals in the environment. However, developments in RADAR RAdio Detection And Ranging) and communications technology are making it harder to effectively identify and maintain bandwidth usage for everyone. Millimeter waves---waves measured between one millimeter to one centimeter in wavelength---have only recently been explored as a new technology to replace the augment receiver architectures. These small wavelengths introduce many engineering challenges, such as: large atmospheric losses, poor sensitivity, and expensive electronic equipment. With growing developments in Microwave Photonics, low-noise RF amplifiers and high-speed modulators have demonstrated the ability to design RF communication links in the millimeter wave regime to counter such problems. However, despite these developments, toward a cost-effective, spatial division multiplexing SDM) receiver concept has not proved capable of being implemented as part of the next generation 5G wireless network infrastructure. To this end, we present a novel receiver architecture utilizing an optically addressed phased-array millimeter wave receiver based on optical-upconversion and signal recovery. This receiver is capable of geolocation and spatial multiplexing of multiple Tunable optically Paired Source TOPS) communication signals in its scene. Operating at 35 GHz, the receiver up-converts the received RF onto an optical sideband, which, to our advantage, contains all of the frequency, amplitude, and phase information of the received signals. Subsequent optical processing allows routing of the sideband to a free space detector port. Photomixing a coherent optical local oscillator LO) with the optical sideband performs heterodyne down-conversion to an Intermediate Frequency IF) whe

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Local control unit for ITER-India gyrotron test facility (IIGTF)

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FUSION engineering AND design 2016年 112卷 897-905页

作者： Rathod, Vipal Shah, Ronak Mandge, Deepak Parmar, Rajvi Rao, S. L. ITER India Inst Plasma Res Gandhinagar 382428 Gujarat India

Electron Cyclotron system on ITER, is one of the important RF ancillary systems based on high power Gyrotron RF sources, that is used for plasma heating and current drive applications. To operate a Gyrotron source, various auxiliary systems and services such as Super Conducting Magnet set, High Voltage Power Supplies, Auxiliary Power Supplies, Waveguide components, Cooling water system and a Local Control Unit (LCU) are required. The LCU plays a very crucial role for the safe and reliable operation of Gyrotron system. A dedicated full scale ITER prototype LCU is being developed for testing and commissioning of an ITER like Test Gyrotron at ITER-India Gyrotron Test facility (IIGTF). The main functions of LCU include Sequence Control, Local Interlock Protection and Real Time Data Acquisition. PLC based slow controller is used for implementing the Sequence Control & Slow Interlock functions. Critical Protection Interlocks are required to have a response time of <10 mu s and are implemented using custom built hardware and PXIe based fast controller. Also PXIe system is used for implementing Real Time Data Acquisition function that is required to have slow and fast acquisition with online visualization and off line analysis facility. A Signal Conditioning Unit (SCU) is used to interface and faithfully transmit the field signals to the remote control systems. Necessary controller hardware is procured and several pre-prototype developments have been taken up to establish the critical subsystems such as protection interlocks and SCU. Software applications for PLC and PXIe systems are being developed using LabVIEW (TM) and CODAC Core System platforms. Here, we provide an overview of the prototype LCU for IIGTF, which includes the architecture, implementation topology, prototype test results along with the current status. (C) 2016 Elsevier B.V. All rights reserved.

关键词： ITER ECH&CD Gyrotron Data acquisition and control optical link

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developments in fiber-positioning technology for the WEAVE instrument at the William Herschel Telescope 6

Developments in fiber-positioning technology for the WEAVE i...

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Ground-Based and Airborne Instrumentation for Astronomy VI

作者： Schallig, Ellen Lewis, Ian J. Gilbert, James Dalton, Gavin Brock, Matthew Abrams, Don Carlos Middleton, Kevin Aguerri, J. Alfonso L. Bonifacio, Piercarlo Carrasco, Esperanza Trager, Scott C. Vallenari, Antonella Dept. of Physics University of Oxford Keble Road OX1 3RH United Kingdom RSAA Mount Stromlo Observatory Cotter Road Weston CreekACT2611 Australia RAL Space Science and Technology Facilities Council Rutherford Appleton Laboratory Harwell Oxford Didcot OxfordshireOX11 OQX United Kingdom Isaac Newton Group Santa Cruz de La Palma38700 Spain Instituto de Astrofisica de Canarias La Laguna Tenerife38200 Spain GEPI Observatiore de Paris Place Jules Janssen Meudon92195 France Mexico Kapteyn Instituut Rijksuniversiteit Groningen Postbus 800 GroningenNL-9700 AV Netherlands Osservatorio Astronomico di Padova INAF Vicolo Osservatorio 5 Padova35122 Italy

ISBN: (数字)9781510601963

ISBN: (纸本)9781510601956

WEAVE is the next-generation wide-field optical spectroscopy facility for the William Herschel Telescope (WHT) on La Palma in the Canary Islands, Spain. It is a multi-object "pick-and-place" fibre-fed spectrograph with a 1000 fibre multiplex behind a new dedicated 2° prime focus corrector. The WEAVE positioner concept uses two robots working in tandem in order to reconfigure a fully populated field within the expected 1 hour dwell-time for the instrument (a good match between the required exposure times and the limit of validity for a given configuration due to the effects of differential refraction). In this paper we describe some of the final design decisions arising from the prototyping phase of the instrument design and provide an update on the current manufacturing status of the fibre positioner system. © 2016 SPIE.

关键词： Fibers

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design, developments, and results from the NIST additive manufacturing metrology testbed (AMMT) 27

Design, developments, and results from the NIST additive man...

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27th Annual International Solid Freeform Fabrication Symposium - An Additive Manufacturing Conference, SFF 2016

作者： Lane, B. Mekhontsev, S. Grantham, S. Vlasea, M.L. Whiting, J. Yeung, H. Fox, J. Zarobila, C. Neira, J. McGlauflin, M. Hanssen, L. Moylan, S. Donmez, A. Rice, J. Engineering Laboratory National Institute of Standards and Technology GaithersburgMD20899 United States Physical Measurement Laboratory National Institute of Standards and Technology GaithersburgMD20899 United States Mechanical and Mechatronics Engineering University of Waterloo WaterlooONN2L 3GI Canada

The National Institute of Standards and Technology (NIST) is developing a facility titled the Additive Manufacturing Metrology Testbed that will enable advanced research into monitoring, controls, process development, and temperature measurement for laser powder bed fusion additive manufacturing and similar processes. This system provides an open control architecture as well as a plethora of sensor systems and calibration sources that are primarily radiance-based and aligned co-axially with the laser beam and focused on the laser interaction zone. This paper briefly reviews the system requirements, and details the current progress of the facility design and construction. Mechanical, optical, and control systems designs are detailed with select highlights that may be relevant to additive manufacturing researchers and system developers. Recent experimental results from the prototype laser control and in-situ monitoring system are also highlighted. © 2016 The Department of Energy’s Kansas City National Security Campus is operated and managed by Honeywell Federal Manufacturing Technologies, LLC under contract number DE-NA0002839.

关键词： 3D printers

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Scanning the Issue

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IETE JOURNAL OF RESEARCH 2016年第2期62卷 127-128页

作者： Koul, Shiban K.

The Volume 62, May-June 2016 issue of IETE Journal of Research contains articles on research and developments taking place in the broad areas of Electrical engineering. The paper 'On feasibility conditions for linear interference alignment over cognitive interference channel: A DoF analysis with diversity tradeoff' presents analytical studies related to multiuser opportunistic interference alignment (OIA) scheme in a multiple-antenna cognitive radio network. The paper 'Cost-effective optimal allocation and sizing of active power filters using a new fuzzy-MABICA method', deals with the active power filters in distribution systems. The next paper titled 'Reversible comparator design using quantum dot-cellular automata', presents the design of a reversible building block for a 1-bit comparator and gives its implementation in quantum dot cellular automata (QCA). The next paper on 'Gate Tunneling current Model for NanoscaleMOSFETS with Varying Surface Potential' deals with development of a simple first-order analytical model for evaluating gate tunnelling current through thin dielectrics in Nanoscale MOSFETs. In the paper on 'A physics-based model of double-gate tunnel FET for circuit simulation', an accurate device physics-based model for double-gate tunnel FET (TFET) is developed and integrated with Cadence circuit simulator.

关键词： Comparators (optical)

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Tolerancing an optical freeform surface: an optical fabricator's perspective 16

Tolerancing an optical freeform surface: an optical fabricat...

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Conference on current developments in Lens design and optical engineering XVI

作者： Nelson, Jessica DeGroote Medicus, Kate Frisch, Gregory Optimax Syst Inc Ontario NY 14519 USA

ISBN: (纸本)9781628417449

Freeform optical shapes or optical surfaces that arc designed with non-symmetric features arc gaining popularity with lens designers and optical system integrators. Tolerances on a freeform optical design influence the optical fabrication process. Case studies and soft tolerance limits for easier fabrication will be discussed. This paper will also give a high level overview of a freeform optical fabrication process that includes generation. high speed VIBE polishing, sub-aperture figure correction and testing of freeform surfaces.

关键词： Freeform optics manufacturing tolerance fabrication asphere

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