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Optical imaging diagnostics for fusion plasmas

Description: Imaging diagnostics are used for spatially/emdash/and temporally/emdash/resolved quantitative measurements of plasma properties such as the ionization particle source, particle and energy loss, and impurity radiation in magnetically confined fusion plasmas. Diagnostics equipped with multi-element solid-state detectors (often with image intensifiers) are well suited to the environment of large fusion machines with high magnetic field and x-ray and neutron fluxes. We have both conventional (16msf… more
Date: April 1, 1988
Creator: Allen, S.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Comparison of Predicted Optical Performance With Measured Results for Dish Concentrators

Description: Several optical design tools have been developed at the National Renewable Energy Laboratory (NREL) during the past two years. These have been used extensively both in-house and by industry to analyze dish concentrator systems and to optimize performance of such designs. The first program, OPTDSH, models single-element dish concentrators. The second code, ODMF, allows multifacet dish arrays to be modeled. The accuracy of performance simulations by these programs has been established by comparin… more
Date: April 1, 1991
Creator: Jorgensen, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High-power pulsed lasers

Description: The ideas that led to the successful construction and operation of large multibeam fusion lasers at the Lawrence Livermore Laboratory are reviewed. These lasers are based on the use of Nd:glass laser materials. However, most of the concepts are applicable to any laser being designed for fusion experimentation. This report is a summary of lectures given by the author at the 20th Scottish University Summer School in Physics, on Laser Plasma Interaction. This report includes basic concepts of the … more
Date: April 2, 1980
Creator: Holzrichter, J.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Determination of Accuracy of Measurements by NREL's Scanning Hartmann Optical Test instrument

Description: NREL's Scanning Hartmann Optical Test (SHOT) instrument is routinely used to characterize the surface of candidate dish concentration elements for solar thermal applications. An approach was devised to quantify the accuracy of these measurements. Excellent reproducibility was exhibited and high confidence established. The SHOT instrument was designed to allow the surface figure of large optical test articles to be accurately specified. Such test articles are nominally parabolic with an f/D rati… more
Date: April 1, 1991
Creator: Jorgensen, G.; Wendelin, T. & Carasso, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Optical coatings for laser fusion applications

Description: Lasers for fusion experiments use thin-film dielectric coatings for reflecting, antireflecting and polarizing surface elements. Coatings are most important to the Nd:glass laser application. The most important requirements of these coatings are accuracy of the average value of reflectance and transmission, uniformity of amplitude and phase front of the reflected or transmitted light, and laser damage threshold. Damage resistance strongly affects the laser's design and performance. The success o… more
Date: April 24, 1980
Creator: Lowdermilk, W.H.; Milam, D. & Rainer, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fusion driver study. Final technical report, April 1, 1978-March 31, 1980

Description: A conceptual design of a multi-megajoule, repetitively pulsed CO/sub 2/ laser system for Inertial Confinement Fusion is presented. System configurations consisting of 50 to 100 kJ modules operating at subatmospheric pressures with multiple pass optical extraction appear feasible with present or near term technology. Overall laser system efficiencies of greater than 10% at repetition rates in excess of 10 Hz are possible with the state-of-the-art pulsed power technology. The synthesis of all the… more
Date: April 1, 1980
Creator: Friedman, H.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Automated in-line measurement of nuclear fuel pellets

Description: The Hanford Engineering Development Laboratory (HEDL) operated by the Westinghouse Hanford Company for the United States Department of Energy is currently developing, fabricating, and evaluating automated fuel fabrication equipment. This program has as its major goals: reduced personnel exposure, improved safeguards/accountability and improved fuel performance. One of the automated equipment items which has been fabricated is a fuel pellet inspection system. This system inspects fuel pellets fo… more
Date: April 1, 1979
Creator: McLemore, D. R. & Nyman, D. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Experiences with Opto-Mechanical Systems that Affect Optical Surfaces at the Sub-Nanometer Level

Description: Projection optical systems built for Extreme Ultraviolet Lithography (EUVL) demonstrated the ability to produce, support and position reflective optical surfaces for achieving transmitted wavefront errors of 1 nm or less. Principal challenges included optical interferometry, optical manufacturing processes, multi-layer coating technology and opto mechanics. Our group was responsible for designing, building and aligning two different projection optical systems: a full-field, 0.1 NA, four-mirror … more
Date: April 3, 2008
Creator: Hale, L C & Taylor, J S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Technical and historical overview of the study at Livermore of porous antireflection coatings

Description: The testing program leading to selection of antireflection coatings for the NOVA laser is reviewed. Limiting problems that prevented use of some coating technologies are described, and estimates are made of the current value of pursuing solutions to those problems.
Date: April 4, 1985
Creator: Milam, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Secondary and compound concentrators for parabolic-dish solar-thermal power systems

Description: A secondary optical element may be added to a parabolic dish solar concentrator to increase the geometric concentration ratio attainable at a given intercept factor. This secondary may be a Fresnel lens or a mirror, such as a compound elliptic concentrator or a hyperbolic trumpet. At a fixed intercept factor, higher overall geometric concentration may be obtainable with a long focal length primary and a suitable secondary matched to it. Use of a secondary to increase the geometric concentration… more
Date: April 15, 1981
Creator: Jaffe, L.D. & Poon, P.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

ECH (electron cyclotron heating) in the Microwave Tokamak Experiment

Description: The Microwave Tokamak Experiment (MTX) at LLNL will investigate electron heating in the MTX tokamak (formerly Alcator-C) at high density (up to 6 x 10/sup 20/ m/sup -3/) and high power by using a free electron laser (FEL). Parameters of the FEL are a peak power up to 8 GW and 50 ns duration, with average power 1 to 2 MW, at a frequency of 250 GHz. The planned input driver for the FEL is a gyrotron oscillator. The FEL output will be transported quasi-optically, inside a 50 cm evacuated pipe, to … more
Date: April 28, 1987
Creator: Stallard, B. W.; Smith, G. R.; James, R. A.; Thomassen, K. I.; Kritz, A. H.; Makowski, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Determination of Accuracy of Measurements by NREL`s Scanning Hartmann Optical Test instrument

Description: NREL`s Scanning Hartmann Optical Test (SHOT) instrument is routinely used to characterize the surface of candidate dish concentration elements for solar thermal applications. An approach was devised to quantify the accuracy of these measurements. Excellent reproducibility was exhibited and high confidence established. The SHOT instrument was designed to allow the surface figure of large optical test articles to be accurately specified. Such test articles are nominally parabolic with an f/D rati… more
Date: April 1, 1991
Creator: Jorgensen, G.; Wendelin, T. & Carasso, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Virtually distortion-free imaging system for large field, high resolution lithography using electrons, ions or other particle beams

Description: Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position. Particle beams, including electrons, ions and neutral particles, may be used as well as electromagnetic radiation.
Date: April 10, 1991
Creator: Hawryluk, A. M. & Ceglio, N. M.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
open access

Comparison of Predicted Optical Performance With Measured Results for Dish Concentrators

Description: Several optical design tools have been developed at the National Renewable Energy Laboratory (NREL) during the past two years. These have been used extensively both in-house and by industry to analyze dish concentrator systems and to optimize performance of such designs. The first program, OPTDSH, models single-element dish concentrators. The second code, ODMF, allows multifacet dish arrays to be modeled. The accuracy of performance simulations by these programs has been established by comparin… more
Date: April 1, 1991
Creator: Jorgensen, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

System Modeling of kJ-class Petawatt Lasers at LLNL

Description: Advanced Radiographic Capability (ARC) project at the National Ignition Facility (NIF) is designed to produce energetic, ultrafast x-rays in the range of 70-100 keV for backlighting NIF targets. The chirped pulse amplification (CPA) laser system will deliver kilo-Joule pulses at an adjustable pulse duration from 1 ps to 50 ps. System complexity requires sophisticated simulation and modeling tools for design, performance prediction, and comprehension of experimental results. We provide a brief o… more
Date: April 14, 2010
Creator: Shverdin, M Y; Rushford, M; Henesian, M A; Boley, C; Haefner, C; Heebner, J E et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Exploratory development of fusion cast calcium fluoride for 1. 06 micrometer pulsed laser optics. Progress report, December 25, 1976--March 25, 1977

Description: This program is an assessment of fusion cast polycrystalline calcium fluoride for optical components of 1.064 micrometer pulsed laser fusion systems. Task areas include casting of essentially stress-free 33 centimeter diameter, 5 centimeter thick ingots, developing surface finishing techniques for optically figured plane and spherical surfaces, and evaluating state-of-the-art antireflection coatings deposited onto specimens of the cast material. During the third quarter, three casting runs were… more
Date: April 1, 1977
Creator: Willingham, C. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

An adaptive optics package designed for astronomical use with a laser guide star tuned to an absorption line of atomic sodium

Description: We present the design and implementation of a very compact adaptive optic system that senses the return light from a sodium guide-star and controls a deformable mirror and a pointing mirror to compensate atmospheric perturbations in the wavefront. The deformable mirror has 19 electrostrictive actuators and triangular subapertures. The wavefront sensor is a Hartmann sensor with lenslets on triangular centers. The high-bandwidth steering mirror assembly incorporates an analog controller that samp… more
Date: April 11, 1994
Creator: Salmon, J. T.; Avicola, K. & Brase, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Multiple-Source Schlieren System (Transonic Wind Tunnel)

Description: A flow visualization system was developed for the Sandia Corporation 12 x 12-inch transonic blowdown wind tunnel. -The arrangement comprises a multiple- source schlieren system with sharp focusing properties to keep the perforated plexiglas side walls out of focus. The detailed mechanical design of the schlieren system is not completed. However, a bench-type setup representative of the final system has been made at the wind tunnel. The system is shown and each component is discussed briefly. (a… more
Date: April 1, 1960
Creator: Spahr, H. R. & Kyrlach, R. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Raman Spectroscopy of n-Type and p-Type GaSb with Multiple Excitation Wavelengths

Description: The interpretation of Raman spectra of GaSb can be complicated by the presence of a so-called surface space charge region (SSCR), resulting in an inhomogeneous near-surface Raman scattering environment. To fully interpret Raman spectra, it is important to have an understanding of the SSCR profile relative to the Raman probe depth. However, a priori determination of even the actual SSCR width is not always possible for GaSb under a wide range of doping levels. The primary objective of this repor… more
Date: April 5, 2007
Creator: Maslar JE, Hurst WS, Wang CA
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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