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current developments in optical design and engineering VI conference

作者： Sinclair, RL Wescam Inc 45 Innovation Drive Flamborough L9H 7L8 ON Canada

ISBN: (纸本)0819422517

High performance infrared optical designs require careful tolerancing to ensure that the as built performance meets the system requirements. Using modem optical design programs a wide variety of single element and group tolerances can be defined and statistical analysis employed to formulate a prediction of the as built performance. When the number of units being produced is small or near diffraction limited performance is required, then a worst case analysis is often employed to generate a more accurate prediction. However, in some situations, such as low F/number lenses, certain effects that may be important are not always adequately addressed by first order tolerance analysis. this paper reviews one such effect;zonal irregularity or slope errors. To quantify the impact of zonal irregularity on the MTF performance of an infrared lens, detailed comparisons are made between measured and predicted performance. Interferometric analysis of the lens element irregularity is incorporated within the design to predict the as built lens line spread function.

关键词： infrared lens optical tolerances interferograms

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design of an F/1.0 spectrograph camera: 'Surfing' the 15 dimensional design space of 1 million optical systems 6

Design of an F/1.0 spectrograph camera: 'Surfing' the 15 dim...

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current developments in optical design and engineering VI conference

作者： Radley, A Univ. College London (United Kingdom)

ISBN: (纸本)0819422517

this paper describes a real time optimization method for optical systems. We examine the features of the Global-Opt optical ray tracing program, which has been developed to provide the optical engineer with interactive optimization capabilities. We illustrate the programs main features through the results of design study into a an F/1.0 camera for use in a planned Astronomical spectrograph this instrument is the High Resolution optical Spectrograph (HROS), which is part of the international Gemini project to build twin 8m aperture telescopes towards the end of the decade. the Global-Opt program allows the optical engineer to ray trace, in batch mode, up to 1 million optical systems over a period of several hours. Once complete, the engineer can explore the properties (i.e. aberrations) of these million systems in real time in order to locate the most suitable one for a particular task this is achieved by transferring the multi-dimensional optimization problem into 3 spatial dimensions in which all the aberrations and variable parameters are represented in a 'landscape' visualization. the user is then able to interact with these moving visualizations in order to attempt system optimization. Animation of these visualizations helps the user identify any features present, which directly represent specific attributes of the design form under investigation. We have noted that these moving features resemble water waves, hence the interactive optimization process described here is made analogous to 'surfing'.

关键词： raytracing optimization aberration spectrograph camera interactive virtual reality

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980 nm InGaAs/AlGaAs quantum well lasers with extremely low beam divergence

980 nm InGaAs/AlGaAs quantum well lasers with extremely low ...

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IEEE International Semiconductor Laser conference

作者： Shun-Tung Yen Gray Lin Der-Cherng Liu Chia-Ming Tsai Chien-Ping Lee Department of Electronics Engineering National Chiao Tung University Hsinchu Taiwan

ISBN: (纸本)078033163X

We report on the fabrication of 980 nm InGaAs-AlGaAs lasers with a specially designed cladding structure. For a 2.5 /spl mu/m wide ridge waveguide structure, the far field pattern has a vertical divergence of only 13/spl deg/ and a lateral divergence of 8/spl deg/. Meanwhile, the threshold current can remain acceptably low. In addition, with another design, a record small vertical far field angle of 11/spl deg/ was obtained.

关键词： Indium gallium arsenide Quantum well lasers Laser beams threshold current Waveguide lasers optical design Fiber lasers Pump lasers optical waveguides Laser theory

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DEVELOPMENT OF AN ION FIGURING SYSTEM FOR CENTIMETER SCALE optical-COMPONENTS 4

DEVELOPMENT OF AN ION FIGURING SYSTEM FOR CENTIMETER SCALE O...

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conference on current developments in optical design and optical engineering IV

作者： FAWCETT, SC DRUEDING, TW BIFANO, TG NASA GEORGE C MARSHALL SPACE FLIGHT CTROPT FABRICAT BRANCHHUNTSVILLEAL 35812

ISBN: (纸本)0819415871

An important step in the fabrication of an optical component involves the imparting of a precise contour on the optic, which can be expensive and time consuming. Ion beam figuring is the imparting of a contour on an optical component by removing material through the impingement of a broad beam of accelerated neutral particles, and provides a highly deterministic method for the final precision figuring (or correcting) of optical components with advantages over conventional methods. the high predictability allows the possibility of single step figuring, resulting in significant time and cost savings. And unlike grinding, polishing and lapping, ion figuring is non-contacting and so avoids several problems including: edge roll off effects, tool wear, and loading of the work piece. It has previously been demonstrated that ion figuring is effective for the correcting of large optical components. these implementations typically use the process for final figure correction on meter class optical components. the work discussed here is the development of the Precision Ion Machining System (PIMS) at NASA's Marshall Space Flight Center, designed for the processing of smaller (less than 10 cm diameter) optics. Initial experiments using a Kaufman type ion source to figure 8 cm diameter fused silica and silicon carbide samples were successful. Experiments involved correcting flat samples and imparting spherical and aspherical contours.

关键词： Ions optical components Silica Silicon carbide Error analysis Spherical lenses Ion beams Surface roughness Particles Polishing

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thE NASA IRTF design PROPOSAL FOR LARGE-FORMAT INFRARED ARRAY CONTROLLER ELECTRONICS 8

THE NASA IRTF DESIGN PROPOSAL FOR LARGE-FORMAT INFRARED ARRA...

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8th SPIE conference on Instrumentation in Astronomy

作者： ONAKA, PM DENAULT, A INST ASTRON HONOLULUHI 96822

ISBN: (纸本)081941493X

the availability of 256x256 pixel infrared focal plane arrays and the current development of (larger) 1024x1024 pixel arrays require the development of control electronics that are flexible and scalable to different format arrays with sufficient speed and precision to perform clocking, readout and real time processing of array signal outputs. this paper details a design proposal for an array controller system based on multiple Digital Signal Processors (DSPs). Derivation of performance specifications is presented in addition to the identification of key support functions and special processing modes. design tradeoffs between various processors, memory, data export, data storage, and display are discussed. the basis for this design is the existing NSFCAM array control electronics which is being incorporated into the CSHELL spectrometer and guider systems currently in use at the NASA IRTF in addition to instruments at other institutions. © 1994 SPIE. All rights reserved.

关键词： NASA

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EXPERIMENTAL DEMONSTRATION OF A HIGH-SPEED FREE-SPACE INTERCONNECT BASED ON optical RING TOPOLOGY

EXPERIMENTAL DEMONSTRATION OF A HIGH-SPEED FREE-SPACE INTERC...

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6th conference on Advances in optical Information Processing

作者： WANG, JM KANTERAKIS, E KATZ, A ZHANG, Y LI, Y MURRAY, N INTERDIGITAL TELECOM INCNEW YORKNY 11021

ISBN: (纸本)081941544X

In this paper, the design and implementation of a high speed optical ring topology based free space optical interconnect is described. this interconnect system operates at 500 MHz and consists of 16 laser transmitters, a four channel free space interconnect, and a fast speed receiver. A Nearest Neighbor interconnect has been successfully demonstrated. At the data rate of 500 MHz, the total system throughput is 8 Gbps. the system can easily be operated at much higher data rates since the rate was only limited by the electronic circuitry. A discussion is given about device issues such as optical switching devices and practical system design issues such as integration and interface with current electronic systems is considered. this interconnect is very promising in the implementation of ultra fast massively parallel SIMD machines.

关键词： Transmitters Free space Switches Free space optics Receivers Liquid crystals GRIN lenses optical interconnects Prisms Electronic circuits

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RESULTS FROM thE LIVERPOOL PROTOTYPE INDUSTRIAL FEL (IFEL)

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NUCLEAR INSTRUMENTS & MEthODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 1994年第1-3期341卷 80-84页

作者： DEARDEN, G QUIRK, EG ALSHAMMAA, AI STUART, RA LUCAS, J DTI National FEL Laboratory Dept. of Electrical Engineering & Electronics The University of Liverpool P.O. Box 147 Liverpool L69 3BX UK

the prototype Industrial FEL (IFEL) now operating at Liverpool is a low current demonstrator and represents the UK's first working FEL. this compact, X-band waveguide design employs a 55 keV, 1 mA electron beam and a permanent magnet wiggler of period 1.9 cm. the concept, construction details and results obtained so far are all presented here. A pre-bunching technique allows gain to be achieved with currents between 10 muA and 1 mA in both oscillator and amplifier configurations. Below 0.25 mA the power varies with current squared. In the amplifier mode, the gain curve resembles that of an optical klystron. For future operation above 1 mA, if the device is saturated, results indicate the maximum energy removed from the beam will be approximately 8-9 keV per electron and the power should be directly proportional to the current.

关键词： Free electron lasers

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VERSATILE MOSAIC CCD CONTROLLER-design 8

VERSATILE MOSAIC CCD CONTROLLER-DESIGN

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8th SPIE conference on Instrumentation in Astronomy

作者： HAN, WY CLAYTON, M WALKER, DD KOREA ASTRON OBSERV TAEJON 305348SOUTH KOREA

ISBN: (纸本)081941493X

current astronomical CCDs (Charge-coupled devices) are limited in size. However, there are increasing demands for larger devices for spectroscopic and direct imaging use. A comparison of the areas of a direct Schmidt-survey plate, and the largest CCD likely to be available in the foreseeable future, serves to illustrate limitations of current electronic technology. Similarly, modern spectrographs can serve either high spectral resolution or multi-object capability, but not both. One could conceive of an updated analogue of a classical coude spectrograph, which would provide both simultaneously, were the enormous detector areas required available. It is with these two long-term applications in view that we consider the prospects for large-scale CCD mosaics. Spectroscopy in particular would benefit from mixed devices in the same mosaic e.g. blue and red- optimised, IR devices etc. We address how optimally to provide the drive waveforms with (1) minimum interconnections and complexity, (2) the ability to mix CCDs, (3) the ability to tune the individual CCD waveforms for optimum low-light level performance, and (4) to conceive an architecture which is indefinitely expansible. Our solution is to multiplex the drive waveforms to the CCDs as well as the signals from them. Minimum chip-count in the sequencing electronics is ensured by using high-density PLD technology (Programmable Logic Device), which enables a module of sixteen or more CCDs to be sequenced from one PLD plus memory. We describe a laboratory prototype, and describe how this could be developed into a system with all the drive electronics for large numbers of CCDs immediately behind the focal plane array. We also summarize our software system for efficiently generating and editing the bitmaps which define the CCD waveforms.

关键词： Charge-coupled devices Computer aided design Control systems Sensors Raster graphics Multiplexing Imaging systems Clocks Prototyping Logic

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FISHEYE PROJECTION LENS FOR LARGE-FORMAT FILM

FISHEYE PROJECTION LENS FOR LARGE-FORMAT FILM

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conference on current developments in optical design and optical engineering III

作者： DOSHI, R HUGHES LEITZ OPT TECHNOL MIDLAND L4R 2H2ONCANADA

In this paper, we present a new fisheye projection lens for 8 perforation 70 mm format film. the lens has an aperture of F/2.4 and a total field of view of 163 degree(s). We discuss design considerations, and compare ... 详细信息

ISBN: (纸本)081941249X

关键词： Modulation transfer functions Distortion Lens design Projection systems Glasses Tolerancing Laminated object manufacturing Optics manufacturing Spatial frequencies Manufacturing

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SURFACE CONTRIBUTIONS OF thE WAVE ABERRATIONS UP TO thE 8th DEGREE

SURFACE CONTRIBUTIONS OF THE WAVE ABERRATIONS UP TO THE 8TH ...

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5th CONF ON current developments IN optical design AND optical engineering

作者： AURIN, FA Carl Zeiss Postfach 1369 Oberkochen D-7082 Germany

ISBN: (纸本)0819406554

Quantities which are necessary for ray tracing in any case are used to calculate the geometrical and the optical path difference. Proceeding from the optical path difference the coefficients of the power series of the wave aberration function are fitted by a method of least squares up to the 8th degree. For a triplet the surface contributions of the different terms of the aberration function and their sums are represented graphically and numerically. Different checks of validity show not only the accuracy but also the uncertainty of the method in each special case. © 1991 SPIE. All rights reserved.

关键词： Aberrations

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