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SPIE Helmet-Mounted and Head-Mounted Displays and Symbology design Requirements ii Conference

作者： DUDFIELD, HJ HARDIMAN, TD SELCON, SJ DEF RES AGCY DEPT MAN MACHINE INTEGRATFARNBOROUGHENGLAND

ISBN: (纸本)0819418188

The Head-Up Display (HUD) and Helmet Mounted Display (HMD) potentially offer the pilot several critical abilities: maintenance of head-out posture; enhanced situational awareness; real world target location and engagement; and provision of enhanced vision displays (e.g. FLIR). Experience with the HUD in current fast-jet cockpits has led to user acceptance and to the display of a wide range of information. Conversely, there is currently minimal experience of flight with HMDs and hence little is known of this technology on mission performance. Although the HMD has the benefit of cueing pilots as they move their head, it is unclear what the appropriate selection of stabilization cues should be, e.g. attitude information. This review considers a number of technological and psychological factors of which designers of HMDs should be aware.

关键词： HUD HMD HUMAN FACTORS SYMBOLOGY

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current methods for technology evaluation: Primary data collection and synthetic methods

Current methods for technology evaluation: Primary data coll...

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Conference on Health Care Technology Policy ii - the Role of Technology in the Cost of Health Care: Providing the Solutions

作者： Goodman, C CLIFFORD GOODMAN & ASSOCIATES WASHINGTONDC 20008

ISBN: (纸本)0819418560

Increased scrutiny of health care technologies is accompanied by greater attention to the quality of the information upon which technology policy decisions are made. In particular, there is greater understanding of, and demand for, technology evaluation methods that embody greater scientific rigor. Methods for evaluating health care technologies can be divided roughly into two main groups: primary data collection methods and synthetic or integrative methods. Improved understanding by analysts and policy makers of the relative strengths and weaknesses of these methods is improving the design and conduct of technology evaluations, as well as the interpretation of study findings for use in health care decision making.

关键词： consensus development cost-effectiveness analysis decision analysis evaluation methods meta-analysis quality of life randomized controlled trials technology assessment

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LIGHTWEIGHT HELMET MOUNTED NIGHT VISION AND FLIR IMAGERY DISPLAY SYSTEMS 2

LIGHTWEIGHT HELMET MOUNTED NIGHT VISION AND FLIR IMAGERY DIS...

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SPIE Helmet-Mounted and Head-Mounted Displays and Symbology design Requirements ii Conference

作者： KENT, D JEWELL, J USN DIV WARFARE CTR AIRCRAFTWARMINSTERPA 18974

ISBN: (纸本)0819418188

Military aviators have a need for lightweight Helmet Mounted Display (HMD) systems capable of displaying Night Vision (NV) imagery (which has been collected at the O.665m-O.93Optm portion of the spectrum), Forward Looking Infrared (FLIR) imagery (which has been collected at the 3-5im and 8-l2im waveband portions of the spectrum) and/or Heads-Up Display (HUD) information. Present HMD systems have excessive head—supported weights and poor centers of gravity (CG), inducing fatigue and creating an unsafe ejection condition. These problems are created mostly by the weight of the optics and optics support structure attached to the side and front of the aviator's helmet. The optics are necessary to redirect the imagery output of a phosphor screen to the aviator's eyes with as much fidelity as possible. An alternative approach to present HMD systems involves the use of a microlaser based image output array. The micro—lasers would be an array of Vertical Cavity Surface Emitting Laser (VCSEL) diodes. VCSELs have circular output beams, as opposed to edge emitting laser diodes which have astigmatic output beams. The VCSEL circular output beam geometry lends itself to the use of micro-lenses. The micro-lenses allow for f/number modulation with a significantly reduced number of optical elements in the optical path during the redirection of the output image to the user's eyes. Reduced optical elements equate to reduced weight and better CG. In addition, this approach may allow for significantly greater fields-of-view (FOV), possibly in excess of 100 degrees. This paper addresses the attributes and drawbacks of current HMD systems (especially NV systems) and the attributes, drawbacks, and technical challenges associated with realization of a HMD utilizing VCSELs as a display illumination source.

关键词： Vertical cavity surface emitting lasers Mirrors Head-mounted displays Charge-coupled devices optical components Image intensifiers Forward looking infrared Goggles Eye Semiconductor lasers

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Recent developments in virtual experience design and production

Recent developments in virtual experience design and product...

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Stereoscopic Displays and Virtual Reality Systems ii

作者： Fisher, Scott S. Telepresence Research Inc. Portola Valley CA USA

ISBN: (纸本)0819417564

Today, the media of VR and Telepresence are in their infancy and the emphasis is still on technology and engineering. But, it is not the hardware people might use that will determine whether VR becomes a powerful medium - instead, it will be the experiences that they are able to have that will drive its acceptance and impact. A critical challenge in the elaboration of these telepresence capabilities will be the development of environments that are as unpredictable and rich in interconnected processes as an actual location or experience. This paper will describe the recent development of several Virtual Experiences including: `Menagerie', an immersive Virtual Environment inhabited by virtual characters designed to respond to and interact with its users;and `The Virtual Brewery', an immersive public VR installation that provides multiple levels of interaction in an artistic interpretation of the brewing process.

关键词： Virtual reality

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Implementation of i-line lithography to 0.30 um design rules

Implementation of i-line lithography to 0.30 um design rules

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optical/Laser Microlithography ViiI

作者： Kim, Keun-Young Kim, Hung-Eil Lee, Ill-Ho Kim, Jin-Su Chun, Jun-Sung Hur, Ik-Boum Moon, Seung-Chan Baik, Ki-Ho Choi, Soo-Han Hyundai Electronics Industries Co. Ltd. Ichon-Kun Kyongki-do South Korea

ISBN: (纸本)0819417882

The optical lithography is extending its life by combining high numerical aperture (NA) optics and shorter wavelength. The shorter wavelength lithography has required the new developments of related technologies. In particular, DUV resists require an entirely different resist chemistry. Much progress has been demonstrated in the field of transparent chemically amplified resists with high sensitivity. However, this DUV lithography (λ = 248 nm) has been delayed for mass production due to their limitations, such as (i) delay time effects, (ii) high cost ownership due to expensive resist materials and laser maintenance, and (iii) critical dimension (CD) variation over topography caused by multireflection of topographic features. On the other hand, i- line lithography (λ = 365 nm) has apparently been applied to 64M DRAM of 0.35 μm design rule, and attempted to 0.30 μm technology which corresponds to 2nd generation 64M DRAM or 1st generation 256 M DRAM. It might be achieved by combination of off-axis illumination (OAI), phase shift mask (PMS) and advanced resist process technique of i-line lithography. Therefore, i-line lithography can be more practical method rather than DUV lithography for the mass production. In this paper, we have optimized the i-line lithographic techniques for the various pattern shape and density for 0.30 μm design rule. Optimum duty ratio was tried to find for line and space, contact hole patterns. The basic rule is to keep the minimum Cr width over 0.30 μm mask. OAI have been applied to get higher contrast of line and space, and even contact hole patterns, and achieve good pattern fidelities of island patterns. By the implementation of OAI, process latitudes were greatly improved compared to that of conventional techniques. In order to optimize the process over the actual topography, optimum numerical aperture (NA) and aperture of the OAI were selected. In conclusion, 0.30 μm design rule device was successfully fabricated by optimizing the advanc

关键词： Ion beam lithography

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ISDN LOOP EXTENSION USING A MID-SPAN AMPLIFIER

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INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS 1995年第3期8卷 219-224页

作者： ERKER, GJ DODDS, DE KRZYMIEN, WA David E. Dodds was born in Saskatoon Canada in 1945. He received the B. Eng. and MSc. degrees from the University of Saskatchewan in 1966 and 1968 respectively. He worked with Bell Northern Research (Ottawa) on PBX design in 1969 1972 and 1978. Since 1969 he has been with the University of Saskatchewan where he is currently Professor of Electrical Engineering. He teaches courses in electronics and communications and also presents short courses on the fundamentals of telephony. Current research interests are in data transmission signal processing architecture and frame synchronization for PCM and spread spectrum systems. He has been granted five patents relating to commercial products in delta-modulation telephone line interfacing and computer data transmission. In 1986 he was on sabbatical leave at BNR Inc. and worked with an ANSI committee on the standardization of FDDI-II a combined voice and data system. Mr. Dodds is a Registered Consulting Engineer in Saskatchewan. Witold A. Krzyden received his MSc. (Eng.) and Ph.D. degrees (both in Electrical Engineering) in 1970 and 1978 respectively from the Poznan Technical University in Poznan Poland. He was awarded the Minister's of Science and Technology Prize of Excellence for his Ph.D. thesis. From 1970 to 1978 he was a Research Engineer and Teaching Assistant and then from 1978 to 1980 an Assistant Professor of Electrical Engineering at the Poznan Technical University. In 1980 he won a Dutch Government Research Fellowship at the Twente University of Technology in Enschede the Netherlands for the year of 1980/1981. In the following year of 1981/82 he was a Research Assistant Professor there. From 1982 to 1986 he was an Assistant Professor of Electrical Engineering at Lakehead University in Thunder Bay Ontario Canada. In 1986 he joined the Univeristy of Alberta and Alberta Telecommunications Research Centre (now Telecommunications Research Laboratories or TRLabs) as an Associate Professor of Electrical Engineering. Currently he is a Professor of E

The 5.5 km range of the basic rate ISDN loop has been extended by using a negative impedance amplifier and by using a 2 wire/4 wire (2w/4w) amplifier. The negative impedance amplifier extends the range of the loop by 1.0 km, whereas the 2w/4w amplifier extends the range by 1.5 km at the expense of increased complexity. As part of the amplifer design, a resistor/capacitor network has been developed which closely matches the characteristic impedance of telephone cable. Error rate tests have been conducted using various lengths of cable and an operating ISDN line.

关键词： ISDN PHYSICAL LAYER BASIC RATE LOOP RANGE EXTENSION

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Reaching for 0.25 um with current available tool set

Reaching for 0.25 um with current available tool set

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Integrated Circuit Metrology, Inspection, and Process Control IX

作者： Thane, Nathan S. Savage ii, Ronald I. Stark, David R. Hollifield Jr., Larry D. SEMATECH Austin TX USA

ISBN: (纸本)0819417874

Early technology learning for 0.25 μm lithography should confirm predictions of tools and processes needed for printing these small image sizes. Improvements are felt to be needed in reticle critical dimension (CD) control, stepper overlay, lens design, and resists for imaging 0.25 μm. Etch technology is also tested for substrate as well as organic ARLs at these line sizes. This paper will present results from efforts to produce 0.25 μm poly, 0.30 μm contacts/vias, and 0.30 μm metal images on a device of realistic topography applications. Poly patterning has been improved by using off axis illumination but the process window is still small. There is a trade off between focus latitude and isolated to dense bias when using annular illumination. While organic ARLs have improved imaging CD control, there is a corresponding loss in CD control during ARL etch. Effects of ARL thickness variation over topography will also cause CD variations when etching to clear the thicker areas. Poly etch itself also contributes to the CD uniformity variations. At the contact masking level the wafer has a fairly planar oxide surface but even with a chemical mechanical polish the oxide thickness will vary due to the underlying topography. Contact patterning studies will include sensitivities of contact imaged CDs to variations in film stack thicknesses and reflectivities. Process windows will be shown for several film stacks with and without ARC for different resist thicknesses. The relationship between oxide thickness and contact CDs will be shown for contacts at 0.30 μm. For metal etch, results will be shown for insitu and dedicated ARL etch tools using various over-etch conditions. The relationship between the resist thickness required for the current ARL and metal etch selectivity and litho patterning capabilities will be discussed. Results will be shown for metal patterns post imaging, ARL etch, and metal etch at 0.30 μm.

关键词： Lithography

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Optimisation of system design and performance to generate ≥1020 Wcm2 2

Optimisation of system design and performance to generate ≥...

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Generation, Amplification, and Measurement of Ultrashort Laser Pulses ii 1995

作者： Edwards, C.B. Barzanti, L.J. Danson, C.N. Key, M.H. Neely, D. Norreys, P. Pepler, D.A. Toner, W.T. Walsh, F.N. Winstone, T.B. Hutchinson, M.H.R. Mercer, I.P. Wilson, D. Zhou, F. Rutherford Appleton Laboratory Chilton Didcot QxonOX11 0QX United Kingdom Blackett Laboratory Imperial College Prince Consort Road London United Kingdom

We report focused intensities of ≥1019 Wem2, with subpicosecond operation of the VULCAN Ndrglass laser at the Rutherford Appleton Laboratory using chirped pulse amplification1 (CPA) techniques. This paper describes novel aspects of the system including: picosecond and subpicosecond diode pumped oscillators2;the use of a regenerative amplifier and system optimisation. The ultrashort pulse generated from an additive pulse modelocked LMA oscillator was stretched from 0.5 ps to ∼ 200 ps in a double pass grating system and amplified from 1 nJ to 50 J, in phosphate glass amplifiers with a final beam aperture of 150 mm diameter. The stretched pulse was recompressed using a pair of gratings (300 × 150 mm, 1740 lines per mm) and focused using an off-axis parabola to avoid nonlinear effects from transmissive optics. The compressed pulse was monitored using a suite of diagnostics to determine the focusability, pulsewidth and spectrum. We also describe the current system development programme, which is in progress and designed to achieve intensities of ∼1020 Wcm-2 to target. © 1995 SPIE. All rights reserved.

关键词： Ultrashort pulses

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current developments in optical design and optical engineering IV

Current Developments in Optical Design and Optical Engineeri...

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current developments in optical design and optical engineering IV 1994

The proceedings contain 45 papers. The topics discussed include: optical design of a two-mirror asymmetrical reshaping system and its application in superbroadband color center lasers;refractive indices of liquids in the infrared spectral region;stability of the optical properties of abnormally dispersive liquids;optical performance of axial gradient and aspheric surface lenses: study and analysis;multilevel Fresnel zone lenses capable of being fabricated with only one binary mask;computer-generated diffractive optical elements for optical interconnections: design and validation codes;and nonphotolithographic fabrication of large computer-generated diffractive optical elements.

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COMPUTER-GENERATED DIFFRACTIVE optical-ELEMENTS FOR optical INTERCONNECTIONS - design AND VALIDATION CODES 4

COMPUTER-GENERATED DIFFRACTIVE OPTICAL-ELEMENTS FOR OPTICAL ...

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Conference on current developments in optical design and optical engineering IV

作者： DIMARTINO, P PERRONE, G MONTROSSET, I POLITECN TORINO DIPARTIMENTO ELETTR I-10129 TURIN ITALY

ISBN: (纸本)0819415871

In this paper we discuss the design of Diffractive optical Elements that can be used for optical interconnections. Q uite general computer programs have been realized for the design and the validation of such optical elements. As examples, in the paper we discuss the design of a 1 to 3, a 1 to 5 and a 1 to 4 interconnections, workingeither in reflection or in transmission.

关键词： Diffractive optical elements optical design Wavefronts optical interconnects optical components Reflection Reflectivity Computing systems Network architectures Resistors

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