A Single-Element Plane Grating Monochromator

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Michael C. Hettrick

2016-01-01

Full Text Available Concerted rotations of a self-focused varied line-space diffraction grating about its groove axis and surface normal define a new geometric class of monochromator. Defocusing is canceled, while the scanned wavelength is reinforced at fixed conjugate distances and horizontal deviation angle. This enables high spectral resolution over a wide band, and is of particular advantage at grazing reflection angles. A new, rigorous light-path formulation employs non-paraxial reference points to isolate the lateral ray aberrations, with those of power-sum ≤ 3 explicitly expanded for a plane grating. Each of these 14 Fermat equations agrees precisely with the value extracted from numerical raytrace simulations. An example soft X-ray design (6° deviation angle and 2 × 4 mrad aperture attains a resolving power > 25 , 000 over a three octave scan range. The proposed rotation scheme is not limited to plane surfaces or monochromators, providing a new degree of freedom in optical design.

Optics and design of the fringe field monochromator for a Schottky field emission gun

International Nuclear Information System (INIS)

Mook, H.W.; Kruit, P.

1999-01-01

For the improvement of high-resolution electron energy loss spectroscopy a new electron source monochromator, based on the Wien filter principle, is presented. In the fringe field monochromator the electric and magnetic filter fields are tightly enclosed by field clamps to satisfy the Wien condition, E=vB. The whole monochromator including the 150 nm energy selection slits (Nanoslits) is positioned in the gun area. Its total length is only 42 mm. Using electron trajectory simulation through the filter fields the dispersion and aberrations are determined. The parasitic astigmatism of the gun lens needs to be corrected using an electrostatic quadrupole field incorporated in the filter. Estimations of the influence of filter electrode misalignment show that at least six filter electrodes must be used to loosen the alignment demands sufficiently. Using theoretical estimations of the Coulomb interaction the final energy resolution, beam brightness and current are predicted. For a Schottky field emission electron gun with typical brightness of 10 8 A/sr m 2 V the monochromator is expected to produce a 50 meV 1 nA beam with a brightness of 10 7

Electron-optical design parameters for a high-resolution electron monochromator

International Nuclear Information System (INIS)

Tanaka, H.; Huebner, R.H.

1976-01-01

Detailed design parameters of a new, high-resolution electron monochromator are presented. The design utilizes a hemispherical filter as the energy-dispersing element and combines both cylindrical and aperture electrostatic lenses to accelerate, decelerate, transport, and focus the electron beam from the cathode to the interaction region

Hard x-ray monochromator with milli-electron volt bandwidth for high-resolution diffraction studies of diamond crystals

Energy Technology Data Exchange (ETDEWEB)

Stoupin, Stanislav; Shvyd' ko, Yuri; Shu Deming; Khachatryan, Ruben; Xiao, Xianghui; DeCarlo, Francesco; Goetze, Kurt; Roberts, Timothy; Roehrig, Christian; Deriy, Alexey [Advanced Photon Source, Argonne National Laboratory, Illinois 60439 (United States)

2012-02-15

We report on design and performance of a high-resolution x-ray monochromator with a spectral bandwidth of {Delta}E{sub X}{approx_equal} 1.5 meV, which operates at x-ray energies in the vicinity of the backscattering (Bragg) energy E{sub H} = 13.903 keV of the (008) reflection in diamond. The monochromator is utilized for high-energy-resolution diffraction characterization of diamond crystals as elements of advanced x-ray crystal optics for synchrotrons and x-ray free-electron lasers. The monochromator and the related controls are made portable such that they can be installed and operated at any appropriate synchrotron beamline equipped with a pre-monochromator.

Velocity monochromator for macro-ions

Energy Technology Data Exchange (ETDEWEB)

Paquin, R; Baril, M [Laval Univ., Quebec City (Canada). Dept. de Physique

1976-09-15

We propose the use of a dynamic monochromator to reduce the energy spread of a macroion source. It is shown that the energy aberration can be corrected using linear acceleration after the particles are separated in a field free drift tube. We give a general expression for the resolution of the monochromator. We verify experimentally that the energy distribution of a beam of cesium ions of 160 eV mean energy could be reduced from 20 eV to 4.5 eV, giving an improvement of 4.3, with this monochromator which has an efficiency of 6%. Two suggestions to improve the transmission of the monochromator are also given.

Velocity monochromator for macro-ions

International Nuclear Information System (INIS)

Paquin, R.; Baril, M.

1976-01-01

We propose the use of a dynamic monochromator to reduce the energy spread of a macroion source. It is shown that the energy aberration can be corrected using linear acceleration after the particles are separated in a field free drift tube. We give a general expression for the resolution of the monochromator. We verify experimentally that the energy distribution of a beam of cesium ions of 160 eV mean energy could be reduced from 20 eV to 4.5 eV, giving an improvement of 4.3, with this monochromator which has an efficiency of 6%. Two suggestions to improve the transmission of the monochromator are also given. (author)

Workshop on cooling of x-ray monochromators on high power beamlines

International Nuclear Information System (INIS)

Matsushita, T.; Ishikawa, T.

1989-03-01

This report is a Workshop on Cooling of X-ray Monochromators on High Power Beamlines held on August 31, 1988 at the Photon Factory during the Third International Conference on Synchrotron Radiation Instrumentation (SRI88). On high power beamlines, especially on insertion device beamlines, heating of crystal monochromators is becoming a serious problem: Researchers observe that the intensity of the X-ray beam on the sample is not proportional to the source intensity because of thermal distortion of the monochromator crystal. This problem will be even more serious on beamlines for the next generation X-ray rings. In the very tight program of the SRI88 conference, only 2 speakers were able to give invited talks closely related to this problem in the session of OPTICAL COMPONENTS FOR HIGH POWER BEAMLINES on Wednesday morning of August 31, 1988. We held this workshop in the afternoon of the same day with the intention of offering further opportunities to exchange information on efforts underway at various laboratories and to discuss ideas how to solve this problem. We also intended that the workshop would be a 'follow-up' to the X-ray optics workshop held at ESRF, Grenoble in September 1987, where the importance of crystal cooling was strongly pointed out. There were 32 participants from 7 countries. 12 people represented their experiences and ideas for reducing thermal distortion of crystal monochromators. Following those presentations, there were discussions on collaborations for solving this important problem. The attendees agreed that exchange of information should be continued by holding such meetings at reasonable intervals. (J.P.N.)

Cascade self-seeding scheme with wake monochromator for narrow-bandwidth X-ray FELs

Energy Technology Data Exchange (ETDEWEB)

Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2010-06-15

Three different approaches have been proposed so far for production of highly monochromatic X-rays from a baseline XFEL undulator: (i) single-bunch selfseeding scheme with a four crystal monochromator in Bragg reflection geometry; (ii) double-bunch self-seeding scheme with a four-crystal monochromator in Bragg reflection geometry; (iii) single-bunch self-seeding scheme with a wake monochromator. A unique element of the X-ray optical design of the last scheme is the monochromatization of X-rays using a single crystal in Bragg-transmission geometry. A great advantage of this method is that the monochromator introduces no path delay of X-rays. This fact eliminates the need for a long electron beam bypass, or for the creation of two precisely separated, identical electron bunches, as required in the other two self-seeding schemes. In its simplest configuration, the self-seeded XFEL consists of an input undulator and an output undulator separated by a monochromator. In some experimental situations this simplest two-undulator configuration is not optimal. The obvious and technically possible extension is to use a setup with three or more undulators separated by monochromators. This amplification-monochromatization cascade scheme is distinguished, in performance, by a small heat-loading of crystals and a high spectral purity of the output radiation. This paper describes such cascade self-seeding scheme with wake monochromators.We present feasibility study and exemplifications for the SASE2 line of the European XFEL. (orig.)

Recovery, modernization and computerization of the monochromator MDR-23

International Nuclear Information System (INIS)

Miranda, L. J.

2012-01-01

For use in the Optics Laboratory, newly created in the CEADEN, one of the necessary equipment is the Monochromator MDR-23, which was necessary for recovery, modernization (replacing the power supply and control) and computerization by designing a VI (virtual instrument) to control stepper motor through a PC using Lab VIEW 7.1 that allows users to select the address mode, the number of steps and the engine speed and give the initial value of the position and limits the range of the monochromator to start working with it. The principle of operation of the program is done in detail to facilitate understanding of how to operate and use the graphical programming designed and achieve efficient use of equipment. (Author)

Output diagnostics of the grazing incidence plane grating monochromator BUMBLE BEE (15 to 1500 eV)

Energy Technology Data Exchange (ETDEWEB)

Jark, W.; Kunz, C.

1985-09-01

The BUMBLE BEE is a bakeable uhv compatible plane grating monochromator, with a fixed exit beam, and the capability to suppress higher order radiation in a wide energy range. The instrument was built to be used in connection with a uhv reflectometer and has a differential pumping section between the optical components and the sample, allowing a pressure of 10/sup -5/ torr in the experimental chamber without influencing the uhv in the monochromator. The monochromator is not optimized for resolution. Due to its location at a beamline with a short source distance we achieve only medium resolving power in the order of E/..delta..E approx. = 200. The primary goal is the suppression of higher orders, fortunately the thus selected operating parameters for the coupled rotations of the optical components also give nearly the highest available output. The instrument is characterized in great detail. The performance of the instrument is discussed and compared with extensive theoretical calculations.

Design of a cryo-cooled artificial channel-cut crystal monochromator for the European XFEL

Energy Technology Data Exchange (ETDEWEB)

Dong, Xiaohao, E-mail: xiaohao.dong@xfel.eu; Sinn, Harald, E-mail: harald.sinn@xfel.eu [European XFEL GmbH, Hamburg, D-22761 (Germany); Shu, Deming, E-mail: shu@aps.anl.gov [Argonne National Laboratory, Argonne, IL 60439, U.S.A (United States)

2016-07-27

An artificial channel-cut crystal monochromator for the hard X-Ray beamlines of SASE 1&2, cryogenically cooled by the so-called pulse tube cooler (cryorefrigerator), is currently under development at the European XFEL ( http://www.xfel.eu/ ). The fabrication is on-going. We present here the crystal optical consideration and the novel cooling configuration, according to the X-Ray FEL pulses proprieties. The mechanical design improvements are pointed out as well to implement such kind of monochromator based on the previous similar design.

Diffractive-refractive optics: (+,-,-,+) X-ray crystal monochromator with harmonics separation.

Science.gov (United States)

Hrdý, Jaromír; Mikulík, Petr; Oberta, Peter

2011-03-01

A new kind of two channel-cut crystals X-ray monochromator in dispersive (+,-,-,+) position which spatially separates harmonics is proposed. The diffracting surfaces are oriented so that the diffraction is inclined. Owing to refraction the diffracted beam is sagittally deviated. The deviation depends on wavelength and is much higher for the first harmonics than for higher harmonics. This leads to spatial harmonics separation. The idea is supported by ray-tracing simulation.

An ultrahigh vacuum monochromator for photophysics beamline

International Nuclear Information System (INIS)

Meenakshi Raja Rao, P.; Padmanabhan, Saraswathy; Raja Sekhar, B.N.; Shastri, Aparna; Khan, H.A.; Sinha, A.K.

2000-08-01

The photophysics beamline designed for carrying out photoabsorption and fluorescence studies using the 450 MeV Synchrotron Radiation Source (SRS), INDUS-1, uses a 1 metre monochromator as premonochromator for monochromatising the continuum. An ultra high vacuum compatible monochromator in Seya-Namioka mount has been designed and fabricated indigenously. The monochromator was assembled and tested for its performance. Wavelength scanning mechanism was tested for its reproducibility and the monochromator was tested for its resolution using UV and VUV sources. An average spectral resolution of 2.5 A was achieved using a 1200 gr/mm grating. A wavelength repeatability of ± 1A was obtained. An ultra high vacuum of 2 X 10 -8 mbar was also achieved in the monochromator. Details of fabrication, assembly and testing are presented in this report. (author)

Mark IV 'Grasshopper' grazing incidence mono-chromator for the Canadian Synchrotron Radiation Facility (CSRF)

International Nuclear Information System (INIS)

Tan, K.H.; Bancroft, G.M.; Coatsworth, L.L.; Yates, B.W.

1982-01-01

The vacuum, mechanical, and optical characteristics of a 'Grasshopper' grazing incidence monochromator for use with a synchrotron radiation source in the 30-300 eV range is described. The monochromator is compatible with ultrahigh vacuum ( -10 Torr throughout), and the motor driven scan mechanism is linear and reliable. The monchromator has been calibrated using several known absorption edges between 36 and 102 eV and a nonlinear least squares fit to the scan equation. These same absorption edges, plus a scan over zero order, show that the present resolution of the monochromator (with 10 and 16 μm exit and entrance slits respectively) is 0.16 A (0.06 eV at the AlLsub(2,3) edge). With 10 μm entrance and exit slits the resolution will be very close to the theoretical Δlambda = 0.083 A

Asymmetric-cut variable-incident-angle monochromator.

Science.gov (United States)

Smither, R K; Graber, T J; Fernandez, P B; Mills, D M

2012-03-01

A novel asymmetric-cut variable-incident-angle monochromator was constructed and tested in 1997 at the Advanced Photon Source of Argonne National Laboratory. The monochromator was originally designed as a high heat load monochromator capable of handling 5-10 kW beams from a wiggler source. This was accomplished by spreading the x-ray beam out on the surface an asymmetric-cut crystal and by using liquid metal cooling of the first crystal. The monochromator turned out to be a highly versatile monochromator that could perform many different types of experiments. The monochromator consisted of two 18° asymmetrically cut Si crystals that could be rotated about 3 independent axes. The first stage (Φ) rotates the crystal around an axis perpendicular to the diffraction plane. This rotation changes the angle of the incident beam with the surface of the crystal without changing the Bragg angle. The second rotation (Ψ) is perpendicular to the first and is used to control the shape of the beam footprint on the crystal. The third rotation (Θ) controls the Bragg angle. Besides the high heat load application, the use of asymmetrically cut crystals allows one to increase or decrease the acceptance angle for crystal diffraction of a monochromatic x-ray beam and allows one to increase or decrease the wavelength bandwidth of the diffraction of a continuum source like a bending-magnet beam or a normal x-ray-tube source. When the monochromator is used in the doubly expanding mode, it is possible to expand the vertical size of the double-diffracted beam by a factor of 10-15. When this was combined with a bending magnet source, it was possible to generate an 8 keV area beam, 16 mm wide by 26 mm high with a uniform intensity and parallel to 1.2 arc sec that could be applied in imaging experiments.

Synchrotron X-ray adaptative monochromator: study and realization of a prototype

International Nuclear Information System (INIS)

Dezoret, D.

1995-01-01

This work presents a study of a prototype of a synchrotron X-ray monochromator. The spectral qualities of this optic are sensitive to the heat loads which are particularly important on third synchrotron generation like ESRF. Indeed, powers generated by synchrotron beams can reach few kilowatts and power densities about a few tens watts per square millimeters. The mechanical deformations of the optical elements of the beamlines issue issue of the heat load can damage their spectral efficiencies. In order to compensate the deformations, wa have been studying the transposition of the adaptive astronomical optics technology to the x-ray field. First, we have considered the modifications of the spectral characteristics of a crystal induced by x-rays. We have established the specifications required to a technological realisation. Then, thermomechanical and technological studies have been required to transpose the astronomical technology to an x-ray technology. After these studies, we have begun the realisation of a prototype. This monochromator is composed by a crystal of silicon (111) bonded on a piezo-electric structure. The mechanical control is a loop system composed by a infrared light, a Shack-Hartmann CDD and wave front analyser. This system has to compensate the deformations of the crystal in the 5 kcV to 60 kcV energy range with a power density of 1 watt per square millimeters. (authors)

APS high heat load monochromator

International Nuclear Information System (INIS)

Lee, W.K.; Mills, D.

1993-02-01

This document contains the design specifications of the APS high heat load (HHL) monochromator and associated accessories as of February 1993. It should be noted that work is continuing on many parts of the monochromator including the mechanical design, crystal cooling designs, etc. Where appropriate, we have tried to add supporting documentation, references to published papers, and calculations from which we based our decisions. The underlying philosophy behind performance specifications of this monochromator was to fabricate a device that would be useful to as many APS users as possible, that is, the design should be as generic as possible. In other words, we believe that this design will be capable of operating on both bending magnet and ID beamlines (with the appropriate changes to the cooling and crystals) with both flat and inclined crystal geometries and with a variety of coolants. It was strongly felt that this monochromator should have good energy scanning capabilities over the classical energy range of about 4 to 20 keywith Si (111) crystals. For this reason, a design incorporating one rotation stage to drive both the first and second crystals was considered most promising. Separate rotary stages for the first and second crystals can sometimes provide more flexibility in their capacities to carry heavy loads (for heavily cooled first crystals or sagittal benders of second crystals), but their tuning capabilities were considered inferior to the single axis approach

Monochromated scanning transmission electron microscopy

International Nuclear Information System (INIS)

Rechberger, W.; Kothleitner, G.; Hofer, F.

2006-01-01

Full text: Electron energy-loss spectroscopy (EELS) has developed into an established technique for chemical and structural analysis of thin specimens in the (scanning) transmission electron microscope (S)TEM. The energy resolution in EELS is largely limited by the stability of the high voltage supply, by the resolution of the spectrometer and by the energy spread of the source. To overcome this limitation a Wien filter monochromator was recently introduced with commercially available STEMs, offering the advantage to better resolve EELS fine structures, which contain valuable bonding information. The method of atomic resolution Z-contrast imaging within an STEM, utilizing a high-angle annular dark-field (HAADF) detector can perfectly complement the excellent energy resolution, since EELS spectra can be collected simultaneously. In combination with a monochromator microscope not only high spatial resolution images can be recorded but also high energy resolution EELS spectra are attainable. In this work we investigated the STEM performance of a 200 kV monochromated Tecnai F20 with a high resolution Gatan Imaging Filter (HR-GIF). (author)

Easily exchangeable x-ray mirrors and hybrid monochromator modules a study of their performance

Energy Technology Data Exchange (ETDEWEB)

Lin, Fan. [Philips Analytical, Asia Pacific, Toa Payoh, (Singapore); Kogan, V. [Philips Analytical, EA Almelo, (Netherlands); Saito, K. [Philips Analytical, Tokyo, (Japan)

1999-12-01

Full text: PreFix prealigned optical mounts allowing rapid and easily changeover will be presented. The benefits of laterally graded multilayer X-Ray mirrors coupled with these Prefix mounts - conversion of divergent beam to parallel beam, increase of intensity by a factor of 3-7, monochromation to {alpha}1 and {alpha}2 and a dynamic range of 10 {sup 4-5} CpS will be demonstrated in areas such as Thin Film and Powder analysis. Data will be shown on a diffraction profile of thin film (Cr/SiO{sub 2}) with and without a mirror and Si powder with and without a mirror. Further enhancement will be demonstrated by combining a channel cut monochromator-collimator with an X-Ray mirror to produce a high intensity, parallel, pure Cu K{alpha}1 beam with a high intensity of up to 4.5 x 10{sup 8} cps and a divergence down to 0.01 deg. The applicability to various ranging from High Resolution to thin film/reflectivity to Rietveld structural refinement and to phase analysis will be shown. The Rocking curve of HEMT 10nm InGaAs on InP will be presented using various `standard` optics and hybrid optics, also Si powder and a Rietveld refinement of CuS0{sub 4}.5H{sub 2}0 and Aspirin. A comparison of the benefits and application of X-Ray Mirrors and Hybrid Mirror/Monochromators will be given. The data presented will show that by using X-Ray Mirrors and Hybrid modules the performance of standard `Laboratory` Diffractometers can be greatly enhanced to a level previously unachievable with great practical benefits. Copyright (1999) Australian X-ray Analytical Association Inc.

MACS low-background doubly focusing neutron monochromator

CERN Document Server

Smee, S A; Scharfstein, G A; Qiu, Y; Brand, P C; Anand, D K; Broholm, C L

2002-01-01

A novel doubly focusing neutron monochromator has been developed as part of the Multi-Analyzer Crystal Spectrometer (MACS) at the NIST Center for Neutron Research. The instrument utilizes a unique vertical focusing element that enables active vertical and horizontal focusing with a large, 357-crystal (1428 cm sup 2), array. The design significantly reduces the amount of structural material in the beam path as compared to similar instruments. Optical measurements verify the excellent focal performance of the device. Analytical and Monte Carlo simulations predict that, when mounted at the NIST cold-neutron source, the device should produce a monochromatic beam (DELTA E=0.2 meV) with flux phi>10 sup 8 n/cm sup 2 s. (orig.)

Calculation of thermal deformations in water-cooled monochromator crystals

International Nuclear Information System (INIS)

Nakamura, Ario; Hashimoto, Shinya; Motohashi, Haruhiko

1994-11-01

Through calculation of temperature distribution and thermal deformation of monochromators, optical degradation by the heat loads in SPring-8 have been discussed. Cooling experiments were made on three models of copper structures with the JAERI Electron Beam Irradiation Stand (JEBIS) and the results were used to estimate heat transfer coefficients in the models. The heat transfer coefficients have been adopted to simulate heating processes on silicon models of the same structures as the copper models, for which radiations from the SPring-8 bending magnet and the JAERI prototype undulator (WPH-33J) were considered. It has been concluded that, in the case of bending magnet (with power density of 0.27[MW/m 2 ] on monochromator surface), the temperature at the surface center reaches about 30[degC] from the initial temperature of 27[degC] in all the models. In the case of WPH-33J (with power density of 8.2[MW/m 2 ]), the temperature reaches about 200 to 280[degC] depending on the models. The radiation from WPH-33J yields slope errors bigger than the Darwin's width(23[μrad]). (author)

A pseudo-curved oriented pyrolytic graphite neutron monochromator

International Nuclear Information System (INIS)

Ettedgui, H.; Gurewitz, E.; Pinto, H.

1979-03-01

A pseudo-curved neutron monochromator with a continuously variable curvature was constructed with four flat pieces of oriented pyrolytic graphite (OPG). Curvatures which yield maximum diffracted intensities were determined for neutrons of wavelengths 1 A and 2.4 A. The increase of the intensity relatively to that of a flat monochromator is by a factor of 2 and 1.5, for 1 A and 2.4 A, respectively. The neutron flux at three positions along the neutron path was determined by gold foils activation and compared with the flux from flat monochromators of OPG and copper

Variable angle asymmetric cut monochromator

International Nuclear Information System (INIS)

Smither, R.K.; Fernandez, P.B.

1993-09-01

A variable incident angle, asymmetric cut, double crystal monochromator was tested for use on beamlines at the Advanced Photon Source (APS). For both undulator and wiggler beams the monochromator can expand area of footprint of beam on surface of the crystals to 50 times the area of incident beam; this will reduce the slope errors by a factor of 2500. The asymmetric cut allows one to increase the acceptance angle for incident radiation and obtain a better match to the opening angle of the incident beam. This can increase intensity of the diffracted beam by a factor of 2 to 5 and can make the beam more monochromatic, as well. The monochromator consists of two matched, asymmetric cut (18 degrees), silicon crystals mounted so that they can be rotated about three independent axes. Rotation around the first axis controls the Bragg angle. The second rotation axis is perpendicular to the diffraction planes and controls the increase of the area of the footprint of the beam on the crystal surface. Rotation around the third axis controls the angle between the surface of the crystal and the wider, horizontal axis for the beam and can make the footprint a rectangle with a minimum. length for this area. The asymmetric cut is 18 degrees for the matched pair of crystals, which allows one to expand the footprint area by a factor of 50 for Bragg angles up to 19.15 degrees (6 keV for Si[111] planes). This monochromator, with proper cooling, will be useful for analyzing the high intensity x-ray beams produced by both undulators and wigglers at the APS

Second crystal cooling on cryogenically cooled undulator and wiggler double crystal monochromators

International Nuclear Information System (INIS)

Knapp, G. S.

1998-01-01

Simple methods for the cooling of the second crystals of cryogenically cooled undulator and wiggler double crystal monochromators are described. Copper braids between the first and second crystals are used to cool the second crystals of the double crystal monochromators. The method has proved successful for an undulator monochromator and we describe a design for a wiggler monochromator

Development of Bent Perfect Crystal Monochromator (II): Experiments for the evaluation of BPC for a monochromator of neutron diffractometers

Energy Technology Data Exchange (ETDEWEB)

Choi, Yong Nam; Kim, Shin Ae; Lee, Chang Hee [KAERI, Taejon (Korea, Republic of); Kim, Sung Kyu [Pusan National Univ., Pusan (Korea, Republic of); Kim, Seong Baek [Kookmin Univ., Seoul (Korea, Republic of); Mikula, P. [NPI, Prague (Czech Republic)

2004-11-01

Various experimental properties of BPC monochromator at the FCD mode of the ST1 test station have been investigated. To test and verify the performance of the Si-BPC monochromator for the substitutional monochromator, diffraction measurements using copper single crystal and polycrystalline copper rod at various diffraction geometries were carried out. Considering the situation of FCD instrument which is used for both single crystal and texture measurement, a special cut silicon BPC slab which contains (331), (311) and (220) diffraction planes would be a best candidate. Diffraction measurements at the monochromatic focusing is the first experimental demonstration of the theoretical properties and give us a suggestion that the simultaneous measurement at both parallel and anti-parallel diffraction positions could be achievable with a reasonal resolution property as well as the intensity gain.

Multi-layer monochromator

International Nuclear Information System (INIS)

Schoenborn, B.P.; Caspar, D.L.D.

1975-01-01

This invention provides an artificial monochromator crystal for efficiently selecting a narrow band of neutron wavelengths from a neutron beam having a Maxwellian wavelength distribution, by providing on a substrate a plurality of germanium layers, and alternate periodic layers of a different metal having tailored thicknesses, shapes, and volumetric and neutron scattering densities. (U.S.)

Monolithic I-Beam Crystal Monochromator

Energy Technology Data Exchange (ETDEWEB)

Bagnasco, John

2001-10-16

Curved crystal, focusing monochromators featuring cubed-root thickness profiles typically employ side-clamped cooling to reduce thermally induced overall bend deformation of the crystal. While performance is improved, residual bend deformation is often an important limiting factor in the monochromator performance. A slightly asymmetric ``I-beam'' crystal cross section with cubed-root flange profiles has been developed to further reduce this effect. Physical motivation, finite-element modeling evaluation and performance characteristics of this design are discussed. Reduction of high mounting stress at the fixed end of the crystal required the soldering of an Invar support fixture to the crystal. Detailed descriptions of this process along with its performance characteristics are also presented.

The development of a 200 kV monochromated field emission electron source

Energy Technology Data Exchange (ETDEWEB)

Mukai, Masaki, E-mail: mmukai@jeol.co.jp [JEOL Ltd., 3-1-2 Musashino, Akishima, Tokyo 196-8558 (Japan); Kim, Judy S. [University of Oxford, Department of Materials, Parks Road, Oxford, OX1 3PH (United Kingdom); Omoto, Kazuya; Sawada, Hidetaka; Kimura, Atsushi; Ikeda, Akihiro; Zhou, Jun; Kaneyama, Toshikatsu [JEOL Ltd., 3-1-2 Musashino, Akishima, Tokyo 196-8558 (Japan); Young, Neil P.; Warner, Jamie H.; Nellist, Peter D.; Kirkland, Angus I. [University of Oxford, Department of Materials, Parks Road, Oxford, OX1 3PH (United Kingdom)

2014-05-01

We report the development of a monochromator for an intermediate-voltage aberration-corrected electron microscope suitable for operation in both STEM and TEM imaging modes. The monochromator consists of two Wien filters with a variable energy selecting slit located between them and is located prior to the accelerator. The second filter cancels the energy dispersion produced by the first filter and after energy selection forms a round monochromated, achromatic probe at the specimen plane. The ultimate achievable energy resolution has been measured as 36 meV at 200 kV and 26 meV at 80 kV. High-resolution Annular Dark Field STEM images recorded using a monochromated probe resolve Si–Si spacings of 135.8 pm using energy spreads of 218 meV at 200 kV and 217 meV at 80 kV respectively. In TEM mode an improvement in non-linear spatial resolution to 64 pm due to the reduction in the effects of partial temporal coherence has been demonstrated using broad beam illumination with an energy spread of 134 meV at 200 kV. - Highlights: • Monochromator for 200 kV aberration corrected TEM and STEM was developed. • Monochromator produces monochromated and achromatic probe at specimen plane. • Ultimate energy resolution was measured to be 36 meV at 200 kV and 26 meV at 80 kV. • Atomic resolution STEM images were recorded using monochromated electron probe. • Improvements of TEM resolution were confirmed using monochromated illumination.

The development of a 200 kV monochromated field emission electron source

International Nuclear Information System (INIS)

Mukai, Masaki; Kim, Judy S.; Omoto, Kazuya; Sawada, Hidetaka; Kimura, Atsushi; Ikeda, Akihiro; Zhou, Jun; Kaneyama, Toshikatsu; Young, Neil P.; Warner, Jamie H.; Nellist, Peter D.; Kirkland, Angus I.

2014-01-01

We report the development of a monochromator for an intermediate-voltage aberration-corrected electron microscope suitable for operation in both STEM and TEM imaging modes. The monochromator consists of two Wien filters with a variable energy selecting slit located between them and is located prior to the accelerator. The second filter cancels the energy dispersion produced by the first filter and after energy selection forms a round monochromated, achromatic probe at the specimen plane. The ultimate achievable energy resolution has been measured as 36 meV at 200 kV and 26 meV at 80 kV. High-resolution Annular Dark Field STEM images recorded using a monochromated probe resolve Si–Si spacings of 135.8 pm using energy spreads of 218 meV at 200 kV and 217 meV at 80 kV respectively. In TEM mode an improvement in non-linear spatial resolution to 64 pm due to the reduction in the effects of partial temporal coherence has been demonstrated using broad beam illumination with an energy spread of 134 meV at 200 kV. - Highlights: • Monochromator for 200 kV aberration corrected TEM and STEM was developed. • Monochromator produces monochromated and achromatic probe at specimen plane. • Ultimate energy resolution was measured to be 36 meV at 200 kV and 26 meV at 80 kV. • Atomic resolution STEM images were recorded using monochromated electron probe. • Improvements of TEM resolution were confirmed using monochromated illumination

Test results of a diamond double-crystal monochromator at the advanced photon source

International Nuclear Information System (INIS)

Fernandez, P.B.; Graber, T.; Krasnicki, S.; Lee, W.; Mills, D.M.; Rogers, C.S.; Assoufid, L.

1997-01-01

We have tested the first diamond double-crystal monochromator at the Advanced Photon Source (APS). The monochromator consisted of two synthetic type 1b (111) diamond plates in symmetric Bragg geometry. We tested two pairs of single-crystal plates: the first pair was 6 mm by 5 mm by 0.25 mm and 6 mm by 5 mm by 0.37 mm; the second set was 7 mm by 5.5 mm by 0.44 mm. The monochromator first crystal was indirectly cooled by edge contact with a water-cooled copper holder. We studied the performance of the monochromator under the high-power x-ray beam delivered by the APS undulator A. We found no indication of thermal distortions or strains even at the highest incident power (280 watts) and power density (123W/mm 2 at normal incidence). The calculated maximum power and power density absorbed by the first crystal were 37 watts and 4.3W/mm 2 , respectively. We also compared the maximum intensity delivered by the diamond monochromator and by a silicon (111) cryogenically cooled monochromator. For energies in the range of 6 to 10 keV, the flux through the diamond monochromator was about a factor of two less than through the silicon monochromator, in good agreement with calculations. We conclude that water-cooled diamond monochromators can handle the high-power beams from the undulator beamlines at the APS. As single-crystal diamond plates of larger size and better quality become available, the use of diamond monochromators will become a very attractive option. copyright 1997 American Institute of Physics

Development of an automated scanning monochromator for sensitivity calibration of the MUSTANG instrument

Science.gov (United States)

Rivers, Thane D.

1992-06-01

An Automated Scanning Monochromator was developed using: an Acton Research Corporation (ARC) Monochromator, Ealing Photomultiplier Tube and a Macintosh PC in conjunction with LabVIEW software. The LabVIEW Virtual Instrument written to operate the ARC Monochromator is a mouse driven user friendly program developed for automated spectral data measurements. Resolution and sensitivity of the Automated Scanning Monochromator System were determined experimentally. The Automated monochromator was then used for spectral measurements of a Platinum Lamp. Additionally, the reflectivity curve for a BaSO4 coated screen has been measured. Reflectivity measurements indicate a large discrepancy with expected results. Further analysis of the reflectivity experiment is required for conclusive results.

Microcontroller-based servo for two-crystal X-ray monochromators.

Science.gov (United States)

Siddons, D P

1998-05-01

Microcontrollers have become increasingly easy to incorporate into instruments as the architectures and support tools have developed. The PIC series is particularly easy to use, and this paper describes a controller used to stabilize the output of a two-crystal X-ray monochromator at a given offset from its peak intensity position, as such monochromators are generally used.

Diamond monochromator for high heat flux synchrotron x-ray beams

International Nuclear Information System (INIS)

Khounsary, A.M.; Smither, R.K.; Davey, S.; Purohit, A.

1992-12-01

Single crystal silicon has been the material of choice for x-ray monochromators for the past several decades. However, the need for suitable monochromators to handle the high heat load of the next generation synchrotron x-ray beams on the one hand and the rapid and on-going advances in synthetic diamond technology on the other make a compelling case for the consideration of a diamond mollochromator system. In this Paper, we consider various aspects, advantage and disadvantages, and promises and pitfalls of such a system and evaluate the comparative an monochromator subjected to the high heat load of the most powerful x-ray beam that will become available in the next few years. The results of experiments performed to evaluate the diffraction properties of a currently available synthetic single crystal diamond are also presented. Fabrication of diamond-based monochromator is within present technical means

Periodic magnetic field as a polarized and focusing thermal neutron spectrometer and monochromator

Energy Technology Data Exchange (ETDEWEB)

Cremer, J. T.; Williams, D. L.; Fuller, M. J.; Gary, C. K.; Piestrup, M. A. [Adelphi Technology, Inc., 2003 East Bayshore Rd., Redwood City, California 94063 (United States); Pantell, R. H.; Feinstein, J. [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Flocchini, R. G.; Boussoufi, M.; Egbert, H. P.; Kloh, M. D.; Walker, R. B. [Davis McClellan Nuclear Radiation Center, University of California, McClellan, California 95652 (United States)

2010-01-15

A novel periodic magnetic field (PMF) optic is shown to act as a prism, lens, and polarizer for neutrons and particles with a magnetic dipole moment. The PMF has a two-dimensional field in the axial direction of neutron propagation. The PMF alternating magnetic field polarity provides strong gradients that cause separation of neutrons by wavelength axially and by spin state transversely. The spin-up neutrons exit the PMF with their magnetic spins aligned parallel to the PMF magnetic field, and are deflected upward and line focus at a fixed vertical height, proportional to the PMF period, at a downstream focal distance that increases with neutron energy. The PMF has no attenuation by absorption or scatter, as with material prisms or crystal monochromators. Embodiments of the PMF include neutron spectrometer or monochromator, and applications include neutron small angle scattering, crystallography, residual stress analysis, cross section measurements, and reflectometry. Presented are theory, experimental results, computer simulation, applications of the PMF, and comparison of its performance to Stern-Gerlach gradient devices and compound material and magnetic refractive prisms.

Periodic magnetic field as a polarized and focusing thermal neutron spectrometer and monochromator.

Science.gov (United States)

Cremer, J T; Williams, D L; Fuller, M J; Gary, C K; Piestrup, M A; Pantell, R H; Feinstein, J; Flocchini, R G; Boussoufi, M; Egbert, H P; Kloh, M D; Walker, R B

2010-01-01

A novel periodic magnetic field (PMF) optic is shown to act as a prism, lens, and polarizer for neutrons and particles with a magnetic dipole moment. The PMF has a two-dimensional field in the axial direction of neutron propagation. The PMF alternating magnetic field polarity provides strong gradients that cause separation of neutrons by wavelength axially and by spin state transversely. The spin-up neutrons exit the PMF with their magnetic spins aligned parallel to the PMF magnetic field, and are deflected upward and line focus at a fixed vertical height, proportional to the PMF period, at a downstream focal distance that increases with neutron energy. The PMF has no attenuation by absorption or scatter, as with material prisms or crystal monochromators. Embodiments of the PMF include neutron spectrometer or monochromator, and applications include neutron small angle scattering, crystallography, residual stress analysis, cross section measurements, and reflectometry. Presented are theory, experimental results, computer simulation, applications of the PMF, and comparison of its performance to Stern-Gerlach gradient devices and compound material and magnetic refractive prisms.

X-ray diffraction characteristics of curved monochromators for sychrotron radiation

International Nuclear Information System (INIS)

Boeuf, A.; Rustichelli, F.; Mazkedian, S.; Puliti, P.; Melone, S.

1978-01-01

A theoretical study is presented concerning the diffraction characteristics of curved monochromators for X-ray synchrotron radiation used at the laboratories of Hamburg, Orsay and Stanford. The investigation was performed by extending to the X-ray case a simple model recently developed and fruitfully employed to describe the neutron diffraction properties of curved monochromators. Several diffraction patterns were obtained corresponding to different monochromator materials (Ge, Si) used by the different laboratories, for different reflecting planes (111), (220), asymmetry angles, X-ray wave-lengths (Mo Kα, Cu Kα, Cr Kα) and curvature radii. The results are discussed in physical terms and their implications on the design of curved monochromators for synchrotron radiation are presented. In particular, the study shows that all the monochromators used in the different laboratories should behave practically as perfect crystals and therefore should have a very low integrated reflectivity corresponding to an optimized wavelength passband Δlambda/lambda approximately 10 -4 . The gain that can be obtained by increasing the curvature, by introducing a gradient in the lattice spacing or by any other kind of imperfection is quite limited and much lower than the desirable value. The adopted model can help in obtaining a possible moderate gain in intensity by also taking into consideration other parameters, such as crystal material, reflecting plane, asymmetry of the reflection and X-ray wavelength. (Auth.)

Designing and commissioning of a prototype double Laue monochromator at CHESS

Science.gov (United States)

Ko, J. Y. Peter; Oswald, Benjamin B.; Savino, James J.; Pauling, Alan K.; Lyndaker, Aaron; Revesz, Peter; Miller, Matthew P.; Brock, Joel D.

2014-03-01

High-energy X-rays are efficiently focused sagittally by a set of asymmetric Laue (transmission) crystals. We designed, built and commissioned a prototype double Laue monochromator ((111) reflection in Si(100)) optimized for high-energy X-rays (30-60 keV). Here, we report our design of novel prototype sagittal bender and highlight results from recent characterization experiments. The design of the bender combines the tuneable bending control afforded by previous leaf-spring designs with the stability and small size of a four-bar bender. The prototype monochromator focuses a 25 mm-wide white beam incident on the first monochromator crystal to a monochromatized 0.6 mm beam waist in the experimental station. Compared to the flux in the same focal spot with the Bragg crystal (without focusing), the prototype Laue monochromator delivered 85 times more at 30 keV.

Designing and commissioning of a prototype double Laue monochromator at CHESS

International Nuclear Information System (INIS)

Ko, J Y Peter; Oswald, Benjamin B; Savino, James J; Pauling, Alan K; Lyndaker, Aaron; Revesz, Peter; Miller, Matthew P; Brock, Joel D

2014-01-01

High-energy X-rays are efficiently focused sagittally by a set of asymmetric Laue (transmission) crystals. We designed, built and commissioned a prototype double Laue monochromator ((111) reflection in Si(100)) optimized for high-energy X-rays (30-60 keV). Here, we report our design of novel prototype sagittal bender and highlight results from recent characterization experiments. The design of the bender combines the tuneable bending control afforded by previous leaf-spring designs with the stability and small size of a four-bar bender. The prototype monochromator focuses a 25 mm-wide white beam incident on the first monochromator crystal to a monochromatized 0.6 mm beam waist in the experimental station. Compared to the flux in the same focal spot with the Bragg crystal (without focusing), the prototype Laue monochromator delivered 85 times more at 30 keV.

A double-multilayer monochromator using a modular design for the Advanced Photon Source

International Nuclear Information System (INIS)

Shu, D.; Yun, W.; Lai, B.; Barraza, J.; Kuzay, T.M.

1994-01-01

A novel double-multilayer monochromator has been designed for the Advanced Photon Source X-ray undulator beamline at Argonne National Laboratory. The monochromator consists of two ultra high-vacuum (UHV) compatible modular vessels, each with a sine-bar driving structure and a water-cooled multilayer holder. A high precision Y-Z stage is used to provide compensating motion for the second multilayer from outside the vacuum chamber so that the monochromator can fix the output monochromatic beam direction and angle during the energy scan in a narrow range. The design details for this monochromator are presented in this paper

Analysis and design of multilayer structures for neutron monochromators and supermirrors

International Nuclear Information System (INIS)

Masalovich, S.

2013-01-01

A relatively simple and accurate analytical model for studying the reflectivity of neutron multilayer monochromators and supermirrors is proposed. Design conditions that must be fulfilled in order to reach the maximum reflectivity are considered. The question of the narrowest bandwidth of a monochromator is discussed and the number of layers required to build such a monochromator is derived. Finally, we propose a new and efficient algorithm for synthesis of a supermirror with specified parameters and discuss some inherent restrictions on an attainable reflectivity. -- Highlights: • The inequality (not equation) that defines the thicknesses of layers was obtained. • Ready-to-use formula for the width of the spectral line was found. • Non-quarter-wave monochromators were suggested. • We propose a new algorithm for design of a neutron supermirror. • The problem of minimizing the number of layers in a supermirror is raised

Software feedback for monochromator tuning at UNICAT (abstract)

Science.gov (United States)

Jemian, Pete R.

2002-03-01

Automatic tuning of double-crystal monochromators presents an interesting challenge in software. The goal is to either maximize, or hold constant, the throughput of the monochromator. An additional goal of the software feedback is to disable itself when there is no beam and then, at the user's discretion, re-enable itself when the beam returns. These and other routine goals, such as adherence to limits of travel for positioners, are maintained by software controls. Many solutions exist to lock in and maintain a fixed throughput. Among these include a hardware solution involving a wave form generator, and a lock-in amplifier to autocorrelate the movement of a piezoelectric transducer (PZT) providing fine adjustment of the second crystal Bragg angle. This solution does not work when the positioner is a slow acting device such as a stepping motor. Proportional integral differential (PID) loops have been used to provide feedback through software but additional controls must be provided to maximize the monochromator throughput. Presented here is a software variation of the PID loop which meets the above goals. By using two floating point variables as inputs, representing the intensity of x rays measured before and after the monochromator, it attempts to maximize (or hold constant) the ratio of these two inputs by adjusting an output floating point variable. These floating point variables are connected to hardware channels corresponding to detectors and positioners. When the inputs go out of range, the software will stop making adjustments to the control output. Not limited to monochromator feedback, the software could be used, with beam steering positioners, to maintain a measure of beam position. Advantages of this software feedback are the flexibility of its various components. It has been used with stepping motors and PZTs as positioners. Various devices such as ion chambers, scintillation counters, photodiodes, and photoelectron collectors have been used as

Realisation of a novel crystal bender for a fast double crystal monochromator

CERN Document Server

Zaeper, R; Wollmann, R; Luetzenkirchen-Hecht, D; Frahm, R

2001-01-01

A novel crystal bender for an X-ray undulator beamline as part of a fast double crystal monochromator development for full EXAFS energy range was characterized. Rocking curves of the monochromator crystal system were recorded under different heat loads and bending forces of the indirectly cooled first Si(1 1 1) crystal. The monochromator development implements new piezo-driven tilt tables with wide angular range to adjust the crystals' Bragg angles and a high pressure actuated bender mechanism for the first crystal.

Construction and characterization of the fringe field monochromator for a field emission gun

Science.gov (United States)

Mook; Kruit

2000-04-01

Although some microscopes have shown stabilities sufficient to attain below 0.1 eV spectral resolution in high-resolution electron energy loss spectroscopy, the intrinsic energy width of the high brightness source (0.3-0.6 eV) has been limiting the resolution. To lower the energy width of the source to 50 meV without unnecessary loss of brightness, a monochromator has been designed consisting of a short (4 mm) fringe field Wien filter and a 150 nm energy selection slit (nanoslit) both to be incorporated in the gun area of the microscope. A prototype has been built and tested in an ultra-high-vacuum setup (10(-9) mbar). The monochromator, operating on a Schottky field emission gun, showed stable and reproducible operation. The nanoslits did not contaminate and the structure remained stable. By measuring the current through the slit structure a direct image of the beam in the monochromator could be attained and the monochromator could be aligned without the use of a microscope. Good dispersed imaging conditions were found indicating an ultimate resolution of 55 meV. A Mark II fringe field monochromator (FFM) was designed and constructed compatible with the cold tungsten field emitter of the VG scanning transmission microscope. The monochromator was incorporated in the gun area of the microscope at IBM T.J. Watson research center, New York. The monochromator was aligned on 100 kV and the energy distribution measured using the monochromator displayed a below 50 meV filtering capability. The retarding Wien filter spectrometer was used to show a 61 meV EELS system resolution. The FFM is shown to be a monochromator which can be aligned without the use of the electron microscope. This makes it directly applicable for scanning transmission microscopy and low-voltage scanning electron microscopy, where it can lower the resolution loss which is caused by chromatic blur of the spot.

Test of a high-heat-load double-crystal diamond monochromator at the advanced photon source

International Nuclear Information System (INIS)

Fernandez, P.B.; Graber, T.; Lee, W.-K.; Mills, D.M.; Rogers, C.S.; Assoufid, L.

1997-01-01

We have tested the first diamond double-crystal monochromator at the advanced photon source (APS). The monochromator consisted of two synthetic type 1b (111) diamond plates in symmetric Bragg geometry. The single-crystal plates were 6 mm x 5 mm x 0.25 mm and 6 mm x 5 mm x 0.37 mm and showed a combination of mosaic spread/strain of the order of 2-4 arcsec over a central 1.4 mm-wide strip. The monochromator first crystal was indirectly cooled by edge contact with a water-cooled copper holder. We studied the performance of the monochromator under the high-power X-ray beam delivered by the APS undulator A. By changing the undulator gap, we varied the power incident on the first crystal and found no indication of thermal distortions or strains even at the highest incident power (200 W) and power density (108 W/mm 2 in normal incidence). The calculated maximum power and power density absorbed by the first crystal were 14.5 W and 2.4 W/mm 2 , respectively. We also compared the maximum intensity delivered by this monochromator and by a silicon (111) cryogenically cooled monochromator. For energies in the range 6-10 keV, the flux through the diamond monochromator was about a factor of two less than through the silicon monochromator, in good agreement with calculations. We conclude that water-cooled diamond monochromators can handle the high-power beams from the undulator beamlines at the APS. As single-crystal diamond plates of larger size and better quality become available, the use of diamond monochromators will become a very attractive option. (orig.)

Use of a mirror as the first optical component for an undulator beamline at the APS

International Nuclear Information System (INIS)

Yun, W.; Khounsary, A.; Lai, B.; Gluskin, E.

1992-09-01

In the design of Sector II of the Synchrotron Radiation Instrumentation (SRI) CAT, an x-ray mirror with multiple coatings is chosen as the first optical component of the undulator beamline. Two significant advantages of using the mirror are: A significant reduction in the peak radiation heat flux and total power on the downstream monochromator, and (2) availability of the wide-bandpass undulator spectrum between 0--30 key to experimental stations with substantially reduced radiation shielding requirements. The second advantage also allows us to place the monochromator outside the first optics enclosure (FOE) at a large distance from the source to further reduce the peak heat flux on the monochromator. The combined effect is that the inclined crystal monochromator may not be necessary, and a multilayer monochromator can be used because the expected heat fluxes are less than the value that has been demonstrated for those monochromators

Beam-smiling in bent-Laue monochromators

International Nuclear Information System (INIS)

Ren, B.; Dilmanian, F. A.; Wu, X. Y.; Huang, X.; Chapman, L. D.; Ivanov, I.; Zhong, Z.; Thomlinson, W. C.

1997-01-01

When a wide fan-shaped x-ray beam is diffracted by a bent crystal in the Laue geometry, the profile of the diffracted beam generally does not appear as a straight line, but as a line with its ends curved up or curved down. This effect, referred to as 'beam-smiling', has been a major obstacle in developing bent-Laue crystal monochromators for medical applications of synchrotron x-ray. We modeled a cylindrically bent crystal using the Finite Element Analysis (FEA) method, and we carried out experiments at the National Synchrotron Light Source and Cornell High Energy Synchrotron Source. Our studies show that, while beam-smiling exists in most of the crystal's area because of anticlastic bending effects, there is a region parallel to the bending axis of the crystal where the diffracted beam is 'smile-free'. By applying asymmetrical bending, this smile-free region can be shifted vertically away from the geometric center of the crystal, as desired. This leads to a novel method of compensating for beam-smiling. We will discuss the method of ''differential bending'' for smile removal, beam-smiling in the Cauchios and the polychromatic geometry, and the implications of the method on developing single- and double-bent Laue monochromators. The experimental results will be discussed, concentrating on specific beam-smiling observation and removal as applied to the new monochromator of the Multiple Energy Computed Tomography [MECT] project of the Medical Department, Brookhaven National Laboratory

MONO: A program to calculate synchrotron beamline monochromator throughputs

International Nuclear Information System (INIS)

Chapman, D.

1989-01-01

A set of Fortran programs have been developed to calculate the expected throughput of x-ray monochromators with a filtered synchrotron source and is applicable to bending magnet and wiggler beamlines. These programs calculate the normalized throughput and filtered synchrotron spectrum passed by multiple element, flat un- focussed monochromator crystals of the Bragg or Laue type as a function of incident beam divergence, energy and polarization. The reflected and transmitted beam of each crystal is calculated using the dynamical theory of diffraction. Multiple crystal arrangements in the dispersive and non-dispersive mode are allowed as well as crystal asymmetry and energy or angle offsets. Filters or windows of arbitrary elemental composition may be used to filter the incident synchrotron beam. This program should be useful to predict the intensities available from many beamline configurations as well as assist in the design of new monochromator and analyzer systems. 6 refs., 3 figs

Modifications to improve entrance slit thermal stability for grasshopper monochromators

Science.gov (United States)

Wallace, Daniel J.; Rogers, Gregory C.; Crossley, Sherry L.

1994-08-01

As new monochromators are designed for high-flux storage rings, computer modeling and thermal engineering can be done to process increased heat loads and achieve mechanical stability. Several older monochromators, such as the Mark 2 and Mark 5 Grasshopper monochromators, which were designed in 1974, have thermal instabilities in their entrance slit mechanisms. The Grasshoppers operating with narrow slits experience closure of the entrance slit from thermal expansion. In extreme cases, the thermal expansion of the precision components has caused permanent mechanical damage, leaving the slit uncalibrated and/or inoperable. For the Mark 2 and Mark 5 Grasshopper monochromators at the Synchrotron Radiation Center, the original 440 stainless steel entrance slit jaws were retrofitted with an Invar (low expansion Fe, Ni alloy) slit jaw. To transfer the heat from the critical components, two flexible heat straps of Cu were attached. These changes allow safe operation with a 10 μm entrance slit width where the previous limit was 30 μm. After an initial 2 min equilibration, the slit remains stable to 10%, with 100 mA of beam current. Additional improvements in slit thermal stability are planned for a third Grasshopper.

A hard X-ray laboratory for monochromator characterisation

Energy Technology Data Exchange (ETDEWEB)

Hamelin, B [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France)

1997-04-01

Since their installation at ILL during the 1970`s the ILL {gamma}-ray diffractometers have been intensively used in the development of neutron monochromators. However, the ageing of the sources and new developments in hard X-ray diffractometry lead to a decision at the end of 1995 to replace the existing {gamma}-ray laboratory with a hard X-ray laboratory, based on a 420 keV generator, making available in the long term several beam-lines for rapid characterisation of monochromator crystals. The facility is now installed and its characteristics and advantages are outlined. (author). 2 refs.

Inclined monochromator for high heat-load synchrotron x-ray radiation

Science.gov (United States)

Khounsary, Ali M.

1994-01-01

A double crystal monochromator including two identical, parallel crystals, each of which is cut such that the normal to the diffraction planes of interest makes an angle less than 90 degrees with the surface normal. Diffraction is symmetric, regardless of whether the crystals are symmetrically or asymmetrically cut, enabling operation of the monochromator with a fixed plane of diffraction. As a result of the inclination of the crystal surface, an incident beam has a footprint area which is elongated both vertically and horizontally when compared to that of the conventional monochromator, reducing the heat flux of the incident beam and enabling more efficient surface cooling. Because after inclination of the crystal only a fraction of thermal distortion lies in the diffraction plane, slope errors and the resultant misorientation of the diffracted beam are reduced.

Design and performance of the ALS double-crystal monochromator

International Nuclear Information System (INIS)

Jones, G.; Ryce, S.; Perera, R.C.C.

1997-01-01

A new open-quotes Cowan typeclose quotes double-crystal monochromator, based on the boomerang design used at NSLS beamline X-24A, has been developed for beamline 9.3.1 at the ALS, a windowless UHV beamline covering the 1-6 keV photon-energy range. Beamline 9.3.1 is designed to simultaneously achieve the goals of high energy resolution, high flux, and high brightness at the sample. The mechanical design has been simplified, and recent developments in technology have been included. Measured mechanical precision of the monochromator shows significant improvement over existing designs. In tests with x-rays at NSLS beamline X-23 A2, maximum deviations in the intensity of monochromatic light were just 7% during scans of several hundred eV in the vicinity of the Cr K edge (6 keV) with the monochromator operating without intensity feedback. Such precision is essential because of the high brightness of the ALS radiation and the overall length of beamline 9.3.1 (26 m)

Beam-smiling in bent-Laue monochromators

International Nuclear Information System (INIS)

Ren, B.; Dilmanian, F.A.; Wu, X.Y.; Huang, X.; Ivanov, I.; Thomlinson, W.C.

1997-01-01

When a wide fan-shaped x-ray beam is diffracted by a bent crystal in the Laue geometry, the profile of the diffracted beam generally does not appear as a straight line, but as a line with its ends curved up or curved down. This effect, referred to as ' beam-smiling', has been a major obstacle in developing bent-Laue crystal monochromators for medical applications of synchrotron x-ray. We modeled a cylindrically bent crystal using the Finite Element Analysis (FEA) method, and we carried out experiments at the National Synchrotron Light Source and Cornell High Energy Synchrotron Source. Our studies show that, while beam-smiling exists in most of the crystal close-quote s area because of anticlastic bending effects, there is a region parallel to the bending axis of the crystal where the diffracted beam is ' smile-free'. By applying asymmetrical bending, this smile-free region can be shifted vertically away from the geometric center of the crystal, as desired. This leads to a novel method of compensating for beam-smiling. We will discuss the method of ' differential bending' for smile removal, beam-smiling in the Cauchios and the polychromatic geometry, and the implications of the method on developing single- and double-bent Laue monochromators. The experimental results will be discussed, concentrating on specific beam-smiling observation and removal as applied to the new monochromator of the Multiple Energy Computed Tomography [MECT] project of the Medical Department, Brookhaven National Laboratory. copyright 1997 American Institute of Physics

1993 CAT workshop on beamline optical designs

Energy Technology Data Exchange (ETDEWEB)

1993-11-01

An Advanced Photon Source (APS) Collaborative Access Team (CAT) Workshop on Beamline Optical Designs was held at Argonne National Laboratory on July 26--27, 1993. The goal of this workshop was to bring together experts from various synchrotron sources to provide status reports on crystal, reflecting, and polarizing optics as a baseline for discussions of issues facing optical designers for CAT beamlines at the APS. Speakers from the European Synchrotron Radiation Facility (ESRF), the University of Chicago, the National Synchrotron Light Source, and the University of Manchester (England) described single- and double-crystal monochromators, mirrors, glass capillaries, and polarizing optics. Following these presentations, the 90 participants divided into three working groups: Crystal Optics Design, Reflecting Optics, and Optics for Polarization Studies. This volume contains copies of the presentation materials from all speakers, summaries of the three working groups, and a ``catalog`` of various monochromator designs.

1993 CAT workshop on beamline optical designs

International Nuclear Information System (INIS)

1993-11-01

An Advanced Photon Source (APS) Collaborative Access Team (CAT) Workshop on Beamline Optical Designs was held at Argonne National Laboratory on July 26--27, 1993. The goal of this workshop was to bring together experts from various synchrotron sources to provide status reports on crystal, reflecting, and polarizing optics as a baseline for discussions of issues facing optical designers for CAT beamlines at the APS. Speakers from the European Synchrotron Radiation Facility (ESRF), the University of Chicago, the National Synchrotron Light Source, and the University of Manchester (England) described single- and double-crystal monochromators, mirrors, glass capillaries, and polarizing optics. Following these presentations, the 90 participants divided into three working groups: Crystal Optics Design, Reflecting Optics, and Optics for Polarization Studies. This volume contains copies of the presentation materials from all speakers, summaries of the three working groups, and a ''catalog'' of various monochromator designs

Design and performance of the ALS double-crystal monochromator

Energy Technology Data Exchange (ETDEWEB)

Jones, G.; Ryce, S.; Perera, R.C.C. [Lawrence Berkeley National Lab., CA (United States)] [and others

1997-04-01

A new {open_quotes}Cowan type{close_quotes} double-crystal monochromator, based on the boomerang design used at NSLS beamline X-24A, has been developed for beamline 9.3.1 at the ALS, a windowless UHV beamline covering the 1-6 keV photon-energy range. Beamline 9.3.1 is designed to simultaneously achieve the goals of high energy resolution, high flux, and high brightness at the sample. The mechanical design has been simplified, and recent developments in technology have been included. Measured mechanical precision of the monochromator shows significant improvement over existing designs. In tests with x-rays at NSLS beamline X-23 A2, maximum deviations in the intensity of monochromatic light were just 7% during scans of several hundred eV in the vicinity of the Cr K edge (6 keV) with the monochromator operating without intensity feedback. Such precision is essential because of the high brightness of the ALS radiation and the overall length of beamline 9.3.1 (26 m).

Development of an imaging VUV monochromator in normal incidence region

Energy Technology Data Exchange (ETDEWEB)

Koog, Joong-San

1996-07-01

This paper describes a development of the two-dimensional imaging monochromator system. A commercial normal incidence monochromator working on off-Rowland circle mounting is used for this purpose. The imaging is achieved with utilizing the pinhole camera effect created by an entrance slit of limited height. The astigmatism in the normal incidence mounting is small compared with a grazing incidence mount, but has a finite value. The point is that for near normal incidence, the vertical focusing with a concave grating is produced at outside across the exit slit. Therefore, by putting a 2-D detector at the position away from the exit slit ({approx}30 cm), a one-to-one correspondence between the position of a point on the detector and where it originated in the source is accomplished. This paper consists of (1) the principle and development of the imaging monochromator using the off-Rowland mounting, including the 2-D detector system, (2) a computer simulation by ray tracing for investigations of the imaging properties of imaging system, and aberration from the spherical concave grating on the exit slit, (3) the plasma light source (TPD-S) for the test experiments, (4) Performances of the imaging monochromator system on the spatial resolution and sensitivity, and (5) the use of this system for diagnostic studies on the JIPP T-IIU tokamak. (J.P.N.)

Development of an imaging VUV monochromator in normal incidence region

International Nuclear Information System (INIS)

Koog, Joong-San.

1996-07-01

This paper describes a development of the two-dimensional imaging monochromator system. A commercial normal incidence monochromator working on off-Rowland circle mounting is used for this purpose. The imaging is achieved with utilizing the pinhole camera effect created by an entrance slit of limited height. The astigmatism in the normal incidence mounting is small compared with a grazing incidence mount, but has a finite value. The point is that for near normal incidence, the vertical focusing with a concave grating is produced at outside across the exit slit. Therefore, by putting a 2-D detector at the position away from the exit slit (∼30 cm), a one-to-one correspondence between the position of a point on the detector and where it originated in the source is accomplished. This paper consists of 1) the principle and development of the imaging monochromator using the off-Rowland mounting, including the 2-D detector system, 2) a computer simulation by ray tracing for investigations of the imaging properties of imaging system, and aberration from the spherical concave grating on the exit slit, 3) the plasma light source (TPD-S) for the test experiments, 4) Performances of the imaging monochromator system on the spatial resolution and sensitivity, and 5) the use of this system for diagnostic studies on the JIPP T-IIU tokamak. (J.P.N.)

Performance of a beam-multiplexing diamond crystal monochromator at the Linac Coherent Light Source

International Nuclear Information System (INIS)

Zhu, Diling; Feng, Yiping; Lemke, Henrik T.; Fritz, David M.; Chollet, Matthieu; Glownia, J. M.; Alonso-Mori, Roberto; Sikorski, Marcin; Song, Sanghoon; Williams, Garth J.; Messerschmidt, Marc; Boutet, Sébastien; Robert, Aymeric; Stoupin, Stanislav; Shvyd'ko, Yuri V.; Terentyev, Sergey A.; Blank, Vladimir D.; Driel, Tim B. van

2014-01-01

A double-crystal diamond monochromator was recently implemented at the Linac Coherent Light Source. It enables splitting pulses generated by the free electron laser in the hard x-ray regime and thus allows the simultaneous operations of two instruments. Both monochromator crystals are High-Pressure High-Temperature grown type-IIa diamond crystal plates with the (111) orientation. The first crystal has a thickness of ∼100 μm to allow high reflectivity within the Bragg bandwidth and good transmission for the other wavelengths for downstream use. The second crystal is about 300 μm thick and makes the exit beam of the monochromator parallel to the incoming beam with an offset of 600 mm. Here we present details on the monochromator design and its performance

Optimization of flat and horizontally curved neutron monochromators for given diffractometer geometries

International Nuclear Information System (INIS)

Graf, H.A.

1983-08-01

The computer program MONREF was written for calculating the integrated intensity and the k-vector distribution produced by mosaic-crystal monochromators in neutron diffractometers of given geometries. The program treats flat and horizontally curved monochromators in Bragg reflection. Its basic algorithm is derived from Zachariasen's coupled differential equations which were modified to include the case of asymmetrically cut crystals. The calculations are restricted to the scattering in the experimental plane. In the first part of the report the program and its applications are described. In the second part a compilation of intensities is presented, calculated for crystals of Cu, Si, Ge and pyrolytic graphite commonly used as monochromators, in a standard diffractometer configuration. (orig.)

Comparison of elliptical and spherical mirrors for the grasshopper monochromators at SSRL

International Nuclear Information System (INIS)

Waldhauer, A.P.

1989-01-01

A comparison of the performance of a spherical and elliptical mirror in the grasshopper monochromator is presented. The problem was studied by ray tracing and then tested using visible (λ=633 nm) laser light. Calculations using ideal optics yield an improvement in flux by a factor of up to 2.7, while tests with visible light show an increase by a factor of 5 because the old spherical mirror is compared to a new, perfect elliptical one. The FWHM of the measured focus is 90 μm with a spherical mirror, and 25 μm with an elliptical one. Elliptical mirrors have been acquired and are now being installed in the two grasshoppers at SSRL

The cryogenic cooling program in high-heat-load optics at the Advanced Photon Source

International Nuclear Information System (INIS)

Rogers, C.S.

1993-07-01

This paper describes some of the aspects of the cryogenic optics program at the Advanced Photon Source (APS). A liquid-nitrogen-cooled, high-vacuum, double crystal monochromator is being fabricated at Argonne National Laboratory (ANL). A pumping system capable of delivering a variable flow rate of up to 10 gallons per minute of pressurized liquid nitrogen and removing 5 kilowatts of x-ray power is also being constructed. This specialized pumping system and monochromator will be used to test the viability of cryogenically cooled, high-heat-load synchrotron optics. It has been determined that heat transfer enhancement will be required for optics used with APS insertion devices. An analysis of a porous-matrix-enhanced monochromator crystal is presented. For the particular case investigated, a heat transfer enhancement factor of 5 to 6 was calculated

Theory of monochromators based on holographic toroidal arrays for the X-UV spectrum band. Tests of the 'TGM 10 metres, 4 degrees' on the ACO storage ring

International Nuclear Information System (INIS)

Lizon a Lugrin, Eric

1988-01-01

As the use of synchrotron radiation is strongly increasing, needs for monochromators in the X-UV range are very important. This research thesis aimed at the development of prototype monochromator based toroidal lamellar arrays with grazing incidence. In the first part, the author recalls theoretical aspects of light scattering rules adapted to a lamellar array, and of wave-matter interaction rules. In the second part, he reports the calculation of the monochromator, its mechanical description, and its implementation on the light line of the ACO storage ring. In the third part, the author reports tests performed without any input slot and in reverse optical configuration on the ACO storage ring. The energy range, the linearity with respect to wave length, the rejection of higher orders of scattered light, flow and resolution are in compliance with expected values [fr

On-line Vibration Diagnostics of the Optical Elements at BL-28 of the Photon Factory

International Nuclear Information System (INIS)

Maruyama, T.; Kashiwagi, T.; Kikuchi, T.; Toyoshima, A.; Kubota, M.; Ono, K.

2007-01-01

We have analyzed the data of encoders attached to optical elements and developed an on-line vibration diagnostics system of the monochromator. After eliminating the vibration source we have been able to improve the performance of the monochromator

Monochromator for synchrotron light with temperature controlled by electrical current on silicon crystal

Energy Technology Data Exchange (ETDEWEB)

Cusatis, Cesar; Souza, Paulo E.N. [Universidade Federal do Parana (LORXI/UFPR), Curitiba, PR (Brazil). Dept. de Fisica. Lab. de Optica de Raios X e Instrumentacao; Franco, Margareth Kobayaski; Kakuno, Edson [Laboratorio Nacional de Luz Sincroton (LNLS), Campinas, SP (Brazil); Gobbi, Angelo; Carvalho Junior, Wilson de [Centro de Pesquisa e Desenvolvimento em Telecomunicacoes (CPqD), Campinas, SP (Brazil)

2011-07-01

Full text. doped silicon crystal was used simultaneously as a monochromator, sensor and actuator in such way that its temperature could be controlled. Ohmic contacts allowed resistance measurements on a perfect silicon crystal, which were correlated to its temperature. Using the ohmic contacts, an electrical current caused Joule heating on the monochromator that was used to control its temperature. A simple stand-alone electronic box controlled the system. The device was built and tested with white beam synchrotron light on the double crystal monochromator of the XRD line of LNLS, Laboratorio Nacional de Luz Sincrotron, Campinas. The first crystal of a double crystal monochromator determines the energy that is delivered to a synchrotron experimental station and its temperature instability is a major source of energy and intensity instability. If the (333) silicon monochromator is at theta Bragg near 45 degree the variation of the diffraction angle is around one second of arc per degree Kelvin. It may take several minutes for the first crystal temperature to stabilize at the beginning of the station operation when the crystal and its environment are cold. With water refrigeration, the average overall temperature of the crystal may be constant, but the temperature of the surface changes with and without the white beam. The time used to wait for stabilization of the beam energy/intensity is lost unless the temperature of the crystal surface is kept constant. One solution for keeping the temperature of the monochromator and its environment constant or nearly constant is Joule heating it with a controlled small electrical current flowing on the surface of a doped perfect crystal. When the white beam is on, this small amount of extra power will be more concentrated at the beam footpath because the resistance is lower in this region due to the higher temperature. In addition, if the crystal itself is used to detect the temperature variation by measuring the electrical

78 FR 32424 - Notice of Issuance of Final Determination Concerning Monochrome Laser Printers

Science.gov (United States)

2013-05-30

... 5200DNG/SP 5210DNG monochrome laser printers for purposes of U.S. Government procurement? LAW AND ANALYSIS... procurement purposes is the United States. Notice of this final determination will be given in the Federal... of certain monochrome laser printers. Based upon the facts presented, CBP has concluded in the final...

Performance tests of a 2-meter grasshopper monochromator at photon factory

International Nuclear Information System (INIS)

Yanagihara, Mihiro; Maezawa, Hideki; Sasaki, Taizo; Suzuki, Yoshio; Iguchi, Yasuo.

1984-12-01

A 2-meter grasshopper monochromator was installed and adjusted at BL-11A in Photon Factory, and performance tests were carried out. The usable photon energy range for the monochromator is 90 to 1000 eV for a 2400 grooves/mm grating, and the flux is 10 8 - 10 9 photons/sec for entrance and exit slit widths of 15 μm. A resolving power of about 2000 is realized at 250 eV for this slit width. (author)

Synchrotron Radiation Beam Line of Piezoelectric Monochromator Control

International Nuclear Information System (INIS)

Ye Shengan; LIU Ping; Zheng Lifang

2009-01-01

It describes a Piezo Amplifier and Servo-controller module applied in the LN2-cooled Monochromator control system. The application of RS232 communication based on EPICS software environment and its software are implemented. (authors)

High luminance monochrome vs. color displays: impact on performance and search

Science.gov (United States)

Krupinski, Elizabeth A.; Roehrig, Hans; Matsui, Takashi

2011-03-01

To determine if diagnostic accuracy and visual search efficiency with a high luminance medical-grade color display are equivalent to a high luminance medical-grade monochrome display. Six radiologists viewed DR chest images, half with a solitary pulmonary nodule and half without. Observers reported whether or not a nodule was present and their confidence in that decision. Total viewing time per image was recorded. On a subset of 15 cases eye-position was recorded. Confidence data were analyzed using MRMC ROC techniques. There was no statistically significant difference (F = 0.0136, p = 0.9078) between color (mean Az = 0.8981, se = 0.0065) and monochrome (mean Az = 0.8945, se = 0.0148) diagnostic performance. Total viewing time per image did not differ significantly (F = 0.392, p = 0.5315) as a function of color (mean = 27.36 sec, sd = 12.95) vs monochrome (mean = 28.04, sd = 14.36) display. There were no significant differences in decision dwell times (true and false, positive and negative) overall for color vs monochrome displays (F = 0.133, p = 0.7154). The true positive (TP) and false positive (FP) decisions were associated with the longest dwell times, the false negatives (FN) with slightly shorter dwell times, and the true negative decisions (TN) with the shortest (F = 50.552, p radiology.

Performance of a beam-multiplexing diamond crystal monochromator at the Linac Coherent Light Source

DEFF Research Database (Denmark)

Zhu, Diling; Feng, Yiping; Stoupin, Stanislav

2014-01-01

A double-crystal diamond monochromator was recently implemented at the Linac Coherent Light Source. It enables splitting pulses generated by the free electron laser in the hard x-ray regime and thus allows the simultaneous operations of two instruments. Both monochromator crystals are High-Pressu...

A water-cooled x-ray monochromator for using off-axis undulator beam

International Nuclear Information System (INIS)

Khounsary, A.; Maser, J.

2000-01-01

Undulator beamlines at third-generation synchrotrons x-ray sources are designed to use the high-brilliance radiation that is contained in the central cone of the generated x-ray beams. The rest of the x-ray beam is often unused. Moreover, in some cases, such as in the zone-plate-based microfocusing beamlines, only a small part of the central radiation cone around the optical axis is used. In this paper, a side-station branch line at the Advanced Photon Source that takes advantage of some of the unused off-axis photons in a microfocusing x-ray beamline is described. Detailed information on the design and analysis of a high-heat-load water-cooled monochromator developed for this beamline is provided

Submicrovolt resolution X-ray monochromators

International Nuclear Information System (INIS)

Trammell, G.T.; Hannon, J.P.

1984-01-01

Two methods are available to obtain monochromatic x-radiation from a white source: wavelength selection and frequency selection. The resolution of wavelength selection methods is limited to 1-10 MeV in the E = 10 KeV range. To exceed this resolution frequency selection methods based on nuclear resonance scattering can be used. Devices which give strong nuclear resonance reflections but weak electronic reflections are candidates for components of frequency selection monochromates. Some examples are discussed

Design and fabrication of a vacuum ultraviolet monochromator using Seya-Namioka mount

International Nuclear Information System (INIS)

Krishnamurty, G.; Sarma, Y.A.; Meenakshi Raja Rao, P.; Bhattacharya, S.S.

1983-01-01

The design and fabrication of a one meter vacuum ultraviolet monochromator in the Seya-Namioka mounting is described. The monochromator consists of a concave replica grating (1200 grooves/mm) blazed at 1500 A. The grating rotates about a vertical axis through the center of grating by means of sine drive mechanism. An EMI 6256 photomultiplier coupled with a VUV scintillator, sodium salicylate, is used to detect the radiation. (author)

X fluorescence spectrometer including at least one toroidal monochromator with logarithmic spiral

International Nuclear Information System (INIS)

Florestan, J.

1986-01-01

This spectrometer includes a X-ray source, an entrance diaphragm, a revolution monochromator with monocrystal thin plates and a seal set in its center, an outer diaphragm and a X-ray detector. A second monochromator can be set between the source and the sample. The thin plates are set so as to be a toroidal ring whose cross section in an axial plane describes a logarithmic spiral [fr

Optimization of a constrained linear monochromator design for neutral atom beams.

Science.gov (United States)

Kaltenbacher, Thomas

2016-04-01

A focused ground state, neutral atom beam, exploiting its de Broglie wavelength by means of atom optics, is used for neutral atom microscopy imaging. Employing Fresnel zone plates as a lens for these beams is a well established microscopy technique. To date, even for favorable beam source conditions a minimal focus spot size of slightly below 1μm was reached. This limitation is essentially given by the intrinsic spectral purity of the beam in combination with the chromatic aberration of the diffraction based zone plate. Therefore, it is important to enhance the monochromaticity of the beam, enabling a higher spatial resolution, preferably below 100nm. We propose to increase the monochromaticity of a neutral atom beam by means of a so-called linear monochromator set-up - a Fresnel zone plate in combination with a pinhole aperture - in order to gain more than one order of magnitude in spatial resolution. This configuration is known in X-ray microscopy and has proven to be useful, but has not been applied to neutral atom beams. The main result of this work is optimal design parameters based on models for this linear monochromator set-up followed by a second zone plate for focusing. The optimization was performed for minimizing the focal spot size and maximizing the centre line intensity at the detector position for an atom beam simultaneously. The results presented in this work are for, but not limited to, a neutral helium atom beam. Copyright © 2016 Elsevier B.V. All rights reserved.

Vibration measurements of high-heat-load monochromators for DESY PETRA III extension

Energy Technology Data Exchange (ETDEWEB)

Kristiansen, Paw, E-mail: paw.kristiansen@fmb-oxford.com [FMB Oxford Ltd, Unit 1 Ferry Mills, Oxford OX2 0ES (United Kingdom); Horbach, Jan; Döhrmann, Ralph; Heuer, Joachim [DESY, Deutsches Elektronen-Synchrotron Hamburg, Notkestrasse 85, 22607 Hamburg (Germany)

2015-05-09

Vibration measurements of a cryocooled double-crystal monochromator are presented. The origins of the vibrations are identified. The minimum achieved vibration of the relative pitch between the two crystals is 48 nrad RMS and the minimum achieved absolute vibration of the second crystal is 82 nrad RMS. The requirement for vibrational stability of beamline optics continues to evolve rapidly to comply with the demands created by the improved brilliance of the third-generation low-emittance storage rings around the world. The challenge is to quantify the performance of the instrument before it is installed at the beamline. In this article, measurement techniques are presented that directly and accurately measure (i) the relative vibration between the two crystals of a double-crystal monochromator (DCM) and (ii) the absolute vibration of the second-crystal cage of a DCM. Excluding a synchrotron beam, the measurements are conducted under in situ conditions, connected to a liquid-nitrogen cryocooler. The investigated DCM utilizes a direct-drive (no gearing) goniometer for the Bragg rotation. The main causes of the DCM vibration are found to be the servoing of the direct-drive goniometer and the flexibility in the crystal cage motion stages. It is found that the investigated DCM can offer relative pitch vibration down to 48 nrad RMS (capacitive sensors, 0–5 kHz bandwidth) and absolute pitch vibration down to 82 nrad RMS (laser interferometer, 0–50 kHz bandwidth), with the Bragg axis brake engaged.

A sub-50meV spectrometer and energy filter for use in combination with 200kV monochromated (S)TEMs.

Science.gov (United States)

Brink, H A; Barfels, M M G; Burgner, R P; Edwards, B N

2003-09-01

A high-energy resolution post-column spectrometer for the purpose of electron energy loss spectroscopy (EELS) and energy-filtered TEM in combination with a monochromated (S)TEM is presented. The prism aberrations were corrected up to fourth order using multipole elements improving the electron optical energy resolution and increasing the acceptance of the spectrometer for a combination of object area and collection angles. Electronics supplying the prism, drift tube, high-tension reference and critical lenses have been newly designed such that, in combination with the new electron optics, a sub-50 meV energy resolution has been realized, a 10-fold improvement over past post-column spectrometer designs. The first system has been installed on a 200 kV monochromated TEM at the Delft University of Technology. Total system energy resolution of sub-100 meV has been demonstrated. For a 1s exposure the resolution degraded to 110 meV as a result of noise. No further degradation in energy resolution was measured for exposures up to 1 min at 120 kV. Spectral resolution measurements, performed on the pi* peak of the BN K-edge, demonstrated a 350 meV (FWHM) peak width at 200 kV. This measure is predominantly determined by the natural line width of the BN K-edge.

Double crystal monochromator controlled by integrated computing on BL07A in New SUBARU, Japan

Energy Technology Data Exchange (ETDEWEB)

Okui, Masato, E-mail: okui@kohzu.co.jp [Kohzu Precision Co., Ltd., 2-6-15, Kurigi, Asao-ku, Kawasaki-shi, Kanagawa 215-8521 (Japan); Laboratory of Advanced Science and Technology for Industry, University of Hyogo (Japan); Yato, Naoki; Watanabe, Akinobu; Lin, Baiming; Murayama, Norio [Kohzu Precision Co., Ltd., 2-6-15, Kurigi, Asao-ku, Kawasaki-shi, Kanagawa 215-8521 (Japan); Fukushima, Sei, E-mail: FUKUSHIMA.Sei@nims.go.jp [Laboratory of Advanced Science and Technology for Industry, University of Hyogo (Japan); National Institute for Material Sciences (Japan); Kanda, Kazuhiro [Laboratory of Advanced Science and Technology for Industry, University of Hyogo (Japan)

2016-07-27

The BL07A beamline in New SUBARU, University of Hyogo, has been used for many studies of new materials. A new double crystal monochromator controlled by integrated computing was designed and installed in the beamline in 2014. In this report we will discuss the unique features of this new monochromator, MKZ-7NS. This monochromator was not designed exclusively for use in BL07A; on the contrary, it was designed to be installed at low cost in various beamlines to facilitate the industrial applications of medium-scale synchrotron radiation facilities. Thus, the design of the monochromator utilized common packages that can satisfy the wide variety of specifications required at different synchrotron radiation facilities. This monochromator can be easily optimized for any beamline due to the fact that a few control parameters can be suitably customized. The beam offset can be fixed precisely even if one of the two slave axes is omitted. This design reduces the convolution of mechanical errors. Moreover, the monochromator’s control mechanism is very compact, making it possible to reduce the size of the vacuum chamber can be made smaller.

X-ray instrumentation: monochromators and mirrors

International Nuclear Information System (INIS)

Rodrigues, A.R.D.

1983-01-01

The main type of X-ray monochromators used with Synchrotron Radiation are discussed in relation to the energy resolution and to the spectral contamination, as well special systems for applications which require simultaneously high flux and resolution. The characteristics for X-ray mirrors necessaries for its utilization with synchrotron radiation are also analized, as conformators of the beam geometry and spectrum. (L.C.) [pt

Optimization of Monochromated TEM for Ultimate Resolution Imaging and Ultrahigh Resolution Electron Energy Loss Spectroscopy

KAUST Repository

Lopatin, Sergei; Cheng, Bin; Liu, Wei-Ting; Tsai, Meng-Lin; He, Jr-Hau; Chuvilin, Andrey

2017-01-01

The performance of a monochromated transmission electron microscope with Wien type monochromator is optimized to achieve an extremely narrow energy spread of electron beam and an ultrahigh energy resolution with spectroscopy. The energy spread in the beam is improved by almost an order of magnitude as compared to specified values. The optimization involves both the monochromator and the electron energy loss detection system. We demonstrate boosted capability of optimized systems with respect to ultra-low loss EELS and sub-angstrom resolution imaging (in a combination with spherical aberration correction).

Optimization of Monochromated TEM for Ultimate Resolution Imaging and Ultrahigh Resolution Electron Energy Loss Spectroscopy

KAUST Repository

Lopatin, Sergei

2017-09-01

The performance of a monochromated transmission electron microscope with Wien type monochromator is optimized to achieve an extremely narrow energy spread of electron beam and an ultrahigh energy resolution with spectroscopy. The energy spread in the beam is improved by almost an order of magnitude as compared to specified values. The optimization involves both the monochromator and the electron energy loss detection system. We demonstrate boosted capability of optimized systems with respect to ultra-low loss EELS and sub-angstrom resolution imaging (in a combination with spherical aberration correction).

Synchrotron X-ray adaptative monochromator: study and realization of a prototype; Monochromateur adaptatif pour rayonnement X synchrotron: etude et realisation d`un prototype

Energy Technology Data Exchange (ETDEWEB)

Dezoret, D.

1995-12-12

This work presents a study of a prototype of a synchrotron X-ray monochromator. The spectral qualities of this optic are sensitive to the heat loads which are particularly important on third synchrotron generation like ESRF. Indeed, powers generated by synchrotron beams can reach few kilowatts and power densities about a few tens watts per square millimeters. The mechanical deformations of the optical elements of the beamlines issue issue of the heat load can damage their spectral efficiencies. In order to compensate the deformations, wa have been studying the transposition of the adaptive astronomical optics technology to the x-ray field. First, we have considered the modifications of the spectral characteristics of a crystal induced by x-rays. We have established the specifications required to a technological realisation. Then, thermomechanical and technological studies have been required to transpose the astronomical technology to an x-ray technology. After these studies, we have begun the realisation of a prototype. This monochromator is composed by a crystal of silicon (111) bonded on a piezo-electric structure. The mechanical control is a loop system composed by a infrared light, a Shack-Hartmann CDD and wave front analyser. This system has to compensate the deformations of the crystal in the 5 kcV to 60 kcV energy range with a power density of 1 watt per square millimeters. (authors).

An elastic, low-background vertical focusing element for a doubly focusing neutron monochromator

International Nuclear Information System (INIS)

Smee, Stephen A.; Brand, Paul C.; Barry, Dwight D.; Broholm, Collin L.; Anand, Dave K.

2001-01-01

A novel, variable radius of curvature, device for the focusing of neutrons is presented. This elastic element consists of a thin variable thickness, constant width, aluminum blade to which diffracting crystals can be attached. When buckled, the blade assumes a circular focal shape, the radius of which is easily controlled by the relative displacement of supporting pivots. Precision electromechanical and optical measurements show that the slope of the buckled blade conforms to a circular arc to within 0.15 degree sign for radii in the range 900 mm< R<10 000 mm. This easily scalable, low mass mechanism is well suited for use in a focusing neutron monochromator, as the parasitic scattering typically associated with traditional lead screw and lever mechanisms is greatly reduced

A Double-Crystal Monochromator for Neutron Stress Diffractometry

Czech Academy of Sciences Publication Activity Database

Em, V.; Balagurov, A. M.; Glazkov, V. P.; Karpov, I. D.; Mikula, Pavol; Miron, N. F.; Somenkov, V. A.; Sumin, V. V.; Šaroun, Jan; Shushunov, M. N.

2017-01-01

Roč. 60, č. 4 (2017), s. 526-532 ISSN 0020-4412 Institutional support: RVO:61389005 Keywords : neutron diffraction * double-crystal * monochromator Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 0.437, year: 2016

Angular distribution measurement of fragment ions from a molecule using a new beamline consisting of a Grasshopper monochromator

Science.gov (United States)

Saito, Norio; Suzuki, Isao H.; Onuki, Hideo; Nishi, Morotake

1989-07-01

Optical characteristics of a new beamline consisting of a premirror, a Grasshopper monochromator, and a refocusing mirror have been investigated. The intensity of the monochromatic soft x-ray was estimated to be about 108 photons/(s 100 mA) at 500 eV with the storage electron energy of 600 MeV and the minimum slit width. This slit width provides a resolution of about 500. Angular distributions of fragment ions from an inner-shell excited nitrogen molecule have been measured with a rotatable time-of-flight mass spectrometer by using this beamline.

Angular distribution measurement of fragment ions from a molecule using a new beamline consisting of a Grasshopper monochromator

International Nuclear Information System (INIS)

Saito, N.; Suzuki, I.H.; Onuki, H.; Nishi, M.

1989-01-01

Optical characteristics of a new beamline consisting of a premirror, a Grasshopper monochromator, and a refocusing mirror have been investigated. The intensity of the monochromatic soft x-ray was estimated to be about 10 8 photons/(s 100 mA) at 500 eV with the storage electron energy of 600 MeV and the minimum slit width. This slit width provides a resolution of about 500. Angular distributions of fragment ions from an inner-shell excited nitrogen molecule have been measured with a rotatable time-of-flight mass spectrometer by using this beamline

Cryogenically cooled monochromators for the Advanced Photon Source

International Nuclear Information System (INIS)

Mills, D.M.

1996-01-01

The use of cryogenically cooled monochromators looks to be a very promising possibility for the Advanced Photon Source. This position has recently been bolstered by several experiments performed on beamlines at the ESRF and CHESS. At the ESRF, several crystal geometries have been tested that were designed for high power densities (approx-gt 150 W/mm 2 ) and moderate total absorbed powers (<200 W). These geometries have proven to be very successful at handling these power parameters with measured strains on the arc-second level. The experiments performed at CHESS were focused on high total power (approx-gt 1000 W) but moderate power densities. As with the previously mentioned experiments, the crystals designed for this application performed superbly with no measurable broadening of the rocking curves on the arc-second level. These experiments will be summarized and, based on these results, the performance of cryogenic monochromators for the APS will be assessed. copyright 1996 American Institute of Physics

Physical evaluation of color and monochrome medical displays using an imaging colorimeter

Science.gov (United States)

Roehrig, Hans; Gu, Xiliang; Fan, Jiahua

2013-03-01

This paper presents an approach to physical evaluation of color and monochrome medical grade displays using an imaging colorimeter. The purpose of this study was to examine the influence of medical display types, monochrome or color at the same maximum luminance settings, on diagnostic performance. The focus was on the measurements of physical characteristics including spatial resolution and noise performance, which we believed could affect the clinical performance. Specifically, Modulation Transfer Function (MTF) and Noise Power Spectrum (NPS) were evaluated and compared at different digital driving levels (DDL) between two EIZO displays.

Composite germanium monochromators - results for the TriCS

Energy Technology Data Exchange (ETDEWEB)

Schefer, J.; Fischer, S.; Boehm, M.; Keller, L.; Horisberger, M.; Medarde, M.; Fischer, P. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1997-09-01

Composite germanium monochromators are in the beginning of their application in neutron diffraction. We show here the importance of the permanent quality control with neutrons on the example of the 311 wafers which will be used on the single crystal diffractometer TriCS at SINQ. (author) 2 figs., 3 refs.

High-flux normal incidence monochromator for circularly polarized synchrotron radiation

International Nuclear Information System (INIS)

Schaefers, F.; Peatman, W.; Eyers, A.; Heckenkamp, C.; Schoenhense, G.; Heinzmann, U.

1986-01-01

A 6.5-m normal incidence monochromator installed at the storage ring BESSY, which is optimized for a high throughput of circularly polarized off-plane radiation at moderate resolution is described. The monochromator employs two exit slits and is specially designed and used for low-signal experiments such as spin- and angle-resolved photoelectron spectroscopy on solids, adsorbates, free atoms, and molecules. The Monk--Gillieson mounting (plane grating in a convergent light beam) allows for large apertures with relatively little astigmatism. With two gratings, a flux of more than 10 11 photons s -1 bandwidth -1 (0.2--0.5 nm) with a circular polarization of more than 90% in the wavelength range from 35 to 675 nm is achieved

Cam-driven monochromator for QEXAFS

Energy Technology Data Exchange (ETDEWEB)

Caliebe, W.A. [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973 (United States); So, I. [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973 (United States); Lenhard, A. [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973 (United States); Siddons, D.P. [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973 (United States)

2006-11-15

We have developed a cam-drive for quickly tuning the energy of an X-ray monochromator through an X-ray absorption edge for quick extended X-ray absorption spectroscopy (QEXAFS). The data are collected using a 4-channel, 12-bit multiplexed VME analog to digital converter and a VME angle encoder. The VME crate controller runs a real-time operating system. This system is capable of collecting 2 EXAFS-scans in 1 s with an energy stability of better than 1 eV. Additional improvements to increase the speed and the energy stability are under way.

Cam-driven monochromator for QEXAFS

Science.gov (United States)

Caliebe, W. A.; So, I.; Lenhard, A.; Siddons, D. P.

2006-11-01

We have developed a cam-drive for quickly tuning the energy of an X-ray monochromator through an X-ray absorption edge for quick extended X-ray absorption spectroscopy (QEXAFS). The data are collected using a 4-channel, 12-bit multiplexed VME analog to digital converter and a VME angle encoder. The VME crate controller runs a real-time operating system. This system is capable of collecting 2 EXAFS-scans in 1 s with an energy stability of better than 1 eV. Additional improvements to increase the speed and the energy stability are under way.

Cam-driven monochromator for QEXAFS

International Nuclear Information System (INIS)

Caliebe, W.A.; So, I.; Lenhard, A.; Siddons, D.P.

2006-01-01

We have developed a cam-drive for quickly tuning the energy of an X-ray monochromator through an X-ray absorption edge for quick extended X-ray absorption spectroscopy (QEXAFS). The data are collected using a 4-channel, 12-bit multiplexed VME analog to digital converter and a VME angle encoder. The VME crate controller runs a real-time operating system. This system is capable of collecting 2 EXAFS-scans in 1 s with an energy stability of better than 1 eV. Additional improvements to increase the speed and the energy stability are under way

A bent Laue-Laue monochromator for a synchrotron-based computed tomography system

CERN Document Server

Ren, B; Chapman, L D; Ivanov, I; Wu, X Y; Zhong, Z; Huang, X

1999-01-01

We designed and tested a two-crystal bent Laue-Laue monochromator for wide, fan-shaped synchrotron X-ray beams for the program multiple energy computed tomography (MECT) at the National Synchrotron Light Source (NSLS). MECT employs monochromatic X-ray beams from the NSLS's X17B superconducting wiggler beamline for computed tomography (CT) with an improved image quality. MECT uses a fixed horizontal fan-shaped beam with the subject's apparatus rotating around a vertical axis. The new monochromator uses two Czochralski-grown Si crystals, 0.7 and 1.4 mm thick, respectively, and with thick ribs on their upper and lower ends. The crystals are bent cylindrically, with the axis of the cylinder parallel to the fan beam, using 4-rod benders with two fixed rods and two movable ones. The bent-crystal feature of the monochromator resolved the difficulties we had had with the flat Laue-Laue design previously used in MECT, which included (a) inadequate beam intensity, (b) excessive fluctuations in beam intensity, and (c) i...

Summary of the recent conference on thin-film neutron optical devices

International Nuclear Information System (INIS)

Majkrzak, C.F.

1989-01-01

The proceedings of the conference of the International Society for Optical Engineering on Thin-Film Neutron Optical Devices: Mirrors, Supermirrors, Multilayer Monochromators, Polarizers and Beam Guides, which was held in San Diego, California in August, 1988, are summarized here. 2 refs

New x-ray optical system for fluorescence beamline at Hasylab

International Nuclear Information System (INIS)

Falkenberg, G.; Tschentscher, T.

2000-01-01

Beamline L at HASYLAB/DESY is actually dedicated to micro x-ray fluorescence (μ-XRF) experiments using the white beam from a bending magnet of the storage ring DORIS III. To extend the applicability of beamline L to other x-ray fluorescence techniques, such as synchrotron radiation total reflection x-ray fluorescence (SR-TXRF) and micro x-ray absorption near edge structures in fluorescence mode (μ-XANES), new x-ray optics have been designed and are under installation at the moment. The suitability of beamline L for SR-TXRF experiments has been shown previously in a number of studies using temporary setups for beam monochromatization and collimation. The new optical system comprises a slit system, a pair of x-ray mirrors for focussing, collimation and high energy cut-off (12 keV and 30 keV), a double multilayer monochromator for broad bandpass applications (TXRF) and a double perfect-crystal monochromator for spectroscopy (XANES, speciation). The multilayer monochromator will utilize a pair of NiC with a spacing of 4.0 nm for the energy range 2-10 keV and a second pair of WB 4 C with a spacing of 3.0 nm for the range 4-30 keV. To extend the energy range for broad bandpass applications to higher photon energies SiGe gradient crystals are foreseen (ΔE/E ∼ 10 -3 ). For the perfect-crystal monochromator we have chosen a pair of Ge 111 crystals for the energy range 2-10 keV and Si 111 crystals for 7-90 keV. To enable the use of low photon energies down to 2 keV the monochromator vessel is sealed to the ring vacuum by a 25 μm thick carbon window. The mirrors and monochromators deflect the beam vertically and can be moved out of the beam independently. Fixed exit geometry permits the illumination of the same sample spot with different wavelength and energy bands. All optical elements accept the full vertical beam opening in order to enable both vertical and horizontal geometries for sample and detector. (author)

Heat load studies of a water-cooled minichannel monochromator for synchrotron x-ray beams

Science.gov (United States)

Freund, Andreas K.; Arthur, John R.; Zhang, Lin

1997-12-01

We fabricated a water-cooled silicon monochromator crystal with small channels for the special case of a double-crystal fixed-exit monochromator design where the beam walks across the crystal when the x-ray energy is changed. The two parts of the cooled device were assembled using a new technique based on low melting point solder. The bending of the system produced by this technique could be perfectly compensated by mechanical counter-bending. Heat load tests of the monochromator in a synchrotron beam of 75 W total power, 3 mm high and 15 mm wide, generated by a multipole wiggler at SSRL, showed that the thermal slope error of the crystal is 1 arcsec/40 W power, in full agreement with finite element analysis. The cooling scheme is adequate for bending magnet beamlines at the ESRF and present wiggler beamlines at the SSRL.

A compact double crystal monochromator for electrochemistry beamline at PLS

CERN Document Server

Rah, S; Kim, G H

2001-01-01

A compact double crystal monochromator based on 16.5'' CF flange has been designed, fabricated and installed for electrochemistry beamline at Pohang light source. The Bragg angle range of the monochromator is 7-75 deg. The mechanical design is modified from typical Boomerang design [J.A. Golovchenko et al., Rev. Sci. Instrum. 52 (1981) 509; J.P. Kirkland, Nucl. Instr. and Meth. A291 (1990) 185] to have fixed beam offset and single driving axis for spectroscopy experiments. The parallelism error of the crystals is minimized to less than 6 mu rad for the range, by using a precision single axis linear guide, Also, the number of mechanical parts in the vacuum is minimized and 1.8x10 sup - sup 9 Torr of vacuum is achieved without baking.

Generating high gray-level resolution monochrome displays with conventional computer graphics cards and color monitors.

Science.gov (United States)

Li, Xiangrui; Lu, Zhong-Lin; Xu, Pengjing; Jin, Jianzhong; Zhou, Yifeng

2003-11-30

Display systems based on conventional computer graphics cards are capable of generating images with about 8-bit luminance resolution. However, most vision experiments require more than 12 bits of luminance resolution. Pelli and Zhang [Spatial Vis. 10 (1997) 443] described a video attenuator for generating high luminance resolution displays on a monochrome monitor, or for driving just the green gun of a color monitor. Here we show how to achieve a white display by adding video amplifiers to duplicate the monochrome signal to drive all three guns of any color monitor. Because of the lack of the availability of high quality monochrome monitors, our method provides an inexpensive way to achieve high-resolution monochromatic displays using conventional, easy-to-get equipment. We describe the design principles, test results, and a few additional functionalities.

Self-seeding scheme with gas monochromator for narrow-bandwidth soft X-ray FELs

Energy Technology Data Exchange (ETDEWEB)

Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2011-03-15

Self-seeding schemes, consisting of two undulators with a monochromator in between, aim at reducing the bandwidth of SASE X-ray FELs. We recently proposed to use a new method of monochromatization exploiting a single crystal in Bragg transmission geometry for self-seeding in the hard X-ray range. Here we consider a possible extension of this method to the soft X-ray range using a cell filled with resonantly absorbing gas as monochromator. The transmittance spectrum in the gas exhibits an absorbing resonance with narrow bandwidth. Then, similarly to the hard X-ray case, the temporal waveform of the transmitted radiation pulse is characterized by a long monochromatic wake. In fact, the FEL pulse forces the gas atoms to oscillate in a way consistent with a forward-propagating, monochromatic radiation beam. The radiation power within this wake is much larger than the equivalent shot noise power in the electron bunch. Further on, the monochromatic wake of the radiation pulse is combined with the delayed electron bunch and amplified in the second undulator. The proposed setup is extremely simple, and composed of as few as two simple elements. These are the gas cell, to be filled with noble gas, and a short magnetic chicane. The installation of the magnetic chicane does not perturb the undulator focusing system and does not interfere with the baseline mode of operation. In this paper we assess the features of gas monochromator based on the use of He and Ne.We analyze the processes in the monochromator gas cell and outside it, touching upon the performance of the differential pumping system as well. We study the feasibility of using the proposed self-seeding technique to generate narrow bandwidth soft X-ray radiation in the LCLS-II soft X-ray beam line. We present conceptual design, technical implementation and expected performances of the gas monochromator self-seeding scheme. (orig.)

Self-seeding scheme with gas monochromator for narrow-bandwidth soft X-ray FELs

International Nuclear Information System (INIS)

Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

2011-03-01

Self-seeding schemes, consisting of two undulators with a monochromator in between, aim at reducing the bandwidth of SASE X-ray FELs. We recently proposed to use a new method of monochromatization exploiting a single crystal in Bragg transmission geometry for self-seeding in the hard X-ray range. Here we consider a possible extension of this method to the soft X-ray range using a cell filled with resonantly absorbing gas as monochromator. The transmittance spectrum in the gas exhibits an absorbing resonance with narrow bandwidth. Then, similarly to the hard X-ray case, the temporal waveform of the transmitted radiation pulse is characterized by a long monochromatic wake. In fact, the FEL pulse forces the gas atoms to oscillate in a way consistent with a forward-propagating, monochromatic radiation beam. The radiation power within this wake is much larger than the equivalent shot noise power in the electron bunch. Further on, the monochromatic wake of the radiation pulse is combined with the delayed electron bunch and amplified in the second undulator. The proposed setup is extremely simple, and composed of as few as two simple elements. These are the gas cell, to be filled with noble gas, and a short magnetic chicane. The installation of the magnetic chicane does not perturb the undulator focusing system and does not interfere with the baseline mode of operation. In this paper we assess the features of gas monochromator based on the use of He and Ne.We analyze the processes in the monochromator gas cell and outside it, touching upon the performance of the differential pumping system as well. We study the feasibility of using the proposed self-seeding technique to generate narrow bandwidth soft X-ray radiation in the LCLS-II soft X-ray beam line. We present conceptual design, technical implementation and expected performances of the gas monochromator self-seeding scheme. (orig.)

Two strategies of lowering surface deformations of internally cooled X-ray optics

Czech Academy of Sciences Publication Activity Database

Oberta, Peter; Áč, V.; Hrdý, Jaromír

2013-01-01

Roč. 729, NOV (2013), s. 302-306 ISSN 0168-9002 R&D Projects: GA MPO FR-TI1/412 Institutional support: RVO:68378271 Keywords : internal cooling * X-ray optics * monochromator Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.316, year: 2013

Optical measurement of thermal deformation of multilayer optics under synchrotron radiation

International Nuclear Information System (INIS)

Revesz, P.; Kazimirov, A.; Bazarov, I.

2007-01-01

An in situ optical technique to visualize surface distortions of the first monochromator crystal under synchrotron beam heat loading has been developed and applied to measure surface profiles of multilayer optics under white wiggler beam at the CHESS A2 beamline. Two identical multilayer structures deposited on Si and SiC substrates have been tested. Comparison of the reconstructed 3D heatbump profiles showed the surface distortions of the multilayer on SiC a factor of two smaller than the same multilayer on a Si substrate

Optical measurement of thermal deformation of multilayer optics under synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Revesz, P. [Cornell University, CHESS, Ithaca, NY 14850 (United States)], E-mail: pr20@cornell.edu; Kazimirov, A.; Bazarov, I. [Cornell University, CHESS, Ithaca, NY 14850 (United States)

2007-11-11

An in situ optical technique to visualize surface distortions of the first monochromator crystal under synchrotron beam heat loading has been developed and applied to measure surface profiles of multilayer optics under white wiggler beam at the CHESS A2 beamline. Two identical multilayer structures deposited on Si and SiC substrates have been tested. Comparison of the reconstructed 3D heatbump profiles showed the surface distortions of the multilayer on SiC a factor of two smaller than the same multilayer on a Si substrate.

Spectrum scanning of monochromator by microcontroller ATtiny 2313

International Nuclear Information System (INIS)

Veklich, A.M.; Boretskij, V.F.; Kleshich, M.M.; Fesenko, S.O.

2009-01-01

The results of interface developing on the base of Atmel microcontroller ATtiny 2313 are shown. This device is dedicated to the spectrum scanning of monochromators by the step motor. The design principles of motor control scheme are analyzed. The original algorithm of microcontroller program was suggested and realized. The principal performance availability of the USB interface for the purpose of the device control by the personal computer is considered.

Mechanical design aspects of a soft X-ray plane grating monochromator

CERN Document Server

Vasina, R; Dolezel, P; Mynar, M; Vondracek, M; Chab, V; Slezak, J A; Comicioli, C; Prince, K C

2001-01-01

A plane grating monochromator based on the SX-700 concept has been constructed for the Materials Science Beamline, Elettra, which is attached to a bending magnet. The tuning range is from 35 to 800 eV with calculated spectral resolving power epsilon/DELTA epsilon better than 4000 in the whole range. The optical elements consist of a toroidal prefocusing mirror, polarization aperture, entrance slit, plane pre-mirror, single plane grating (blazed), spherical mirror, exit slit and toroidal refocusing mirror. The plane grating is operated in the fixed focus mode with C sub f sub f =2.4. Energy scanning is performed by rotation of the plane grating and simultaneous translation and rotation of the plane pre-mirror. A novel solution is applied for the motion of the plane pre-mirror, namely by a translation and mechanically coupling the rotation by a cam. The slits have no moving parts in vacuum to reduce cost and increase ruggedness, and can be fully closed without risk of damage. In the first tests, a resolving pow...

In-situ reactive of x-ray optics by glow discharge

International Nuclear Information System (INIS)

Johnson, E.D.; Garrett, R.F.

1987-01-01

We have developed a method of in-situ reactive glow discharge cleaning of x-ray optical surfaces which is capable of complete removal of carbon contamination. Our work is the first to successfully clean an entire optical system in-situ and characterize its performance at short wavelengths (as low as 10 /angstrom/). The apparatus required is quite simple and can easily be fitted to most existing UHV (ultra high vacuum) mirror boxes of monochromators. The advantages of this technique over previously available methods include dramatic improvements in instrument performance and reductions in down time since the whole process typically takes a few days. This paper will briefly describe our results and detail the experimental considerations for application of the technique on different monochromator geometries. Possible improvements and extensions of the technique are also discussed

Collimator type monochromator as a possible impurities monitor for fusion plasmas. Preliminary tests on the Tokamak TM-1-MH

International Nuclear Information System (INIS)

Musa, G.; Lungu, C.P.; Badalec, J.; Jakubka, K.; Kopecky, V.; Stoeckel, J.; Zacek, F.

1984-09-01

A collimator type monochromator has been tested for the first time as the impurity monitor on Tokamak. The possibility to use this type of monochromator in fusion devices is analyzed and a monoslit device is proposed as a convenient monitor for impurities. (authors)

Optimization of a constrained linear monochromator design for neutral atom beams

International Nuclear Information System (INIS)

Kaltenbacher, Thomas

2016-01-01

A focused ground state, neutral atom beam, exploiting its de Broglie wavelength by means of atom optics, is used for neutral atom microscopy imaging. Employing Fresnel zone plates as a lens for these beams is a well established microscopy technique. To date, even for favorable beam source conditions a minimal focus spot size of slightly below 1 μm was reached. This limitation is essentially given by the intrinsic spectral purity of the beam in combination with the chromatic aberration of the diffraction based zone plate. Therefore, it is important to enhance the monochromaticity of the beam, enabling a higher spatial resolution, preferably below 100 nm. We propose to increase the monochromaticity of a neutral atom beam by means of a so-called linear monochromator set-up – a Fresnel zone plate in combination with a pinhole aperture – in order to gain more than one order of magnitude in spatial resolution. This configuration is known in X-ray microscopy and has proven to be useful, but has not been applied to neutral atom beams. The main result of this work is optimal design parameters based on models for this linear monochromator set-up followed by a second zone plate for focusing. The optimization was performed for minimizing the focal spot size and maximizing the centre line intensity at the detector position for an atom beam simultaneously. The results presented in this work are for, but not limited to, a neutral helium atom beam. - Highlights: • The presented results are essential for optimal operation conditions of a neutral atom microscope set-up. • The key parameters for the experimental arrangement of a neutral microscopy set-up are identified and their interplay is quantified. • Insights in the multidimensional problem provide deep and crucial understanding for pushing beyond the apparent focus limitations. • This work points out the trade-offs for high intensity and high spatial resolution indicating several use cases.

Optimization of a constrained linear monochromator design for neutral atom beams

Energy Technology Data Exchange (ETDEWEB)

Kaltenbacher, Thomas

2016-04-15

A focused ground state, neutral atom beam, exploiting its de Broglie wavelength by means of atom optics, is used for neutral atom microscopy imaging. Employing Fresnel zone plates as a lens for these beams is a well established microscopy technique. To date, even for favorable beam source conditions a minimal focus spot size of slightly below 1 μm was reached. This limitation is essentially given by the intrinsic spectral purity of the beam in combination with the chromatic aberration of the diffraction based zone plate. Therefore, it is important to enhance the monochromaticity of the beam, enabling a higher spatial resolution, preferably below 100 nm. We propose to increase the monochromaticity of a neutral atom beam by means of a so-called linear monochromator set-up – a Fresnel zone plate in combination with a pinhole aperture – in order to gain more than one order of magnitude in spatial resolution. This configuration is known in X-ray microscopy and has proven to be useful, but has not been applied to neutral atom beams. The main result of this work is optimal design parameters based on models for this linear monochromator set-up followed by a second zone plate for focusing. The optimization was performed for minimizing the focal spot size and maximizing the centre line intensity at the detector position for an atom beam simultaneously. The results presented in this work are for, but not limited to, a neutral helium atom beam. - Highlights: • The presented results are essential for optimal operation conditions of a neutral atom microscope set-up. • The key parameters for the experimental arrangement of a neutral microscopy set-up are identified and their interplay is quantified. • Insights in the multidimensional problem provide deep and crucial understanding for pushing beyond the apparent focus limitations. • This work points out the trade-offs for high intensity and high spatial resolution indicating several use cases.

Focusing Optics for High-Energy X-ray Diffraction

DEFF Research Database (Denmark)

Leinert, U.; Schulze, C.; Honkimäki, V.

1998-01-01

Novel focusing optical devices have been developed for synchrotron radiation in the energy range 40-100 keV. Firstly, a narrow-band-pass focusing energy-tuneable fixed-exit monochromator was constructed by combining meridionally bent Laue and Bragg crystals. Dispersion compensation was applied...

Improving Beamline X-ray Optics by Analyzing the Damage to Crystallographic Structure

Energy Technology Data Exchange (ETDEWEB)

Zientek, John; Maj, Jozef; Navrotski, Gary; Srajer, George; Harmata, Charles; Maj, Lech; Lazarski, Krzysztof; Mikula, Stanislaw

2015-01-02

The mission of the X-ray Characterization Laboratory in the X-ray Science Division (XSD) at the Advanced Photon Source (APS) is to support both the users and the Optics Fabrication Facility that produces high performance optics for synchrotron X-ray beamlines. The Topography Test Unit (TTU) in the X-ray Lab has been successfully used to characterize diffracting crystals and test monochromators by quantifying residual surface stresses. This topographic method has also been adapted for testing standard X-ray mirrors, characterizing concave crystal optics and in principle, can be used to visualize residual stresses on any optic made from single crystalline material. The TTU has been instrumental in quantitatively determining crystal mounting stresses which are mechanically induced by positioning, holding, and cooling fixtures. It is this quantitative aspect that makes topography so useful since the requirements and responses for crystal optics and X-ray mirrors are quite different. In the case of monochromator crystals, even small residual or induced stresses, on the order of tens of kPa, can cause detrimental distortions to the perfect crystal rocking curves. Mirrors, on the other hand, are much less sensitive to induced stresses where stresses that are an order of magnitude greater can be tolerated. This is due to the fact that the surface rather than the lattice-spacing determines a mirror’s performance. For the highly sensitive crystal optics, it is essential to measure the in-situ rocking curves using topographs as mounting fixtures are adjusted. In this way, high heat-load monochromator crystals can be successfully mounted with minimum stress. Topographical analysis has been shown to be a highly effective method to visualize and quantify the distribution of stresses, to help identify methods that mitigate stresses, and most notably to improve diffractive crystal optic rocking curves.

Mechanical design of thin-film diamond crystal mounting apparatus for coherence preservation hard x-ray optics

International Nuclear Information System (INIS)

Shu, Deming; Shvyd’ko, Yuri V.; Stoupin, Stanislav; Kim, Kwang-Je

2016-01-01

A new thin-film diamond crystal mounting apparatus has been designed at the Advanced Photon Source (APS) for coherence preservation hard x-ray optics with optimized thermal contact and minimized crystal strain. This novel mechanical design can be applied to new development in the field of: x-ray optics cavities for hard x-ray free-electron laser oscillators (XFELOs), self-seeding monochromators for hard x-ray free-electron laser (XFEL) with high average thermal loading, high heat load diamond crystal monochromators and beam-sharing/beam-split-and-delay devices for XFEL facilities and future upgraded high-brightness coherent x-ray source in the MBA lattice configuration at the APS.

Mechanical design of thin-film diamond crystal mounting apparatus for coherence preservation hard x-ray optics

Energy Technology Data Exchange (ETDEWEB)

Shu, Deming, E-mail: shu@aps.anl.gov; Shvyd’ko, Yuri V.; Stoupin, Stanislav; Kim, Kwang-Je [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, U.S.A (United States)

2016-07-27

A new thin-film diamond crystal mounting apparatus has been designed at the Advanced Photon Source (APS) for coherence preservation hard x-ray optics with optimized thermal contact and minimized crystal strain. This novel mechanical design can be applied to new development in the field of: x-ray optics cavities for hard x-ray free-electron laser oscillators (XFELOs), self-seeding monochromators for hard x-ray free-electron laser (XFEL) with high average thermal loading, high heat load diamond crystal monochromators and beam-sharing/beam-split-and-delay devices for XFEL facilities and future upgraded high-brightness coherent x-ray source in the MBA lattice configuration at the APS.

Is cold better ? - exploring the feasibility of liquid-helium-cooled optics

International Nuclear Information System (INIS)

Assoufid, L.; Mills, D.; Macrander, A.; Tajiri, G.

1999-01-01

Both simulations and recent experiments conducted at the Advanced Photon Source showed that the performance of liquid-nitrogen-cooled single-silicon crystal monochromators can degrade in a very rapid nonlinear fashion as the power and for power density is increased. As a further step towards improving the performance of silicon optics, we propose cooling with liquid helium, which dramatically improves the thermal properties of silicon beyond that of liquid nitrogen and brings the performance of single silicon-crystal-based synchrotrons radiation optics up to the ultimate limit. The benefits of liquid helium cooling as well as some of the associated technical challenges will be discussed, and results of thermal and structural finite elements simulations comparing the performance of silicon monochromators cooled with liquid nitrogen and helium will be given

Numerical simulation methods for electron and ion optics

International Nuclear Information System (INIS)

Munro, Eric

2011-01-01

This paper summarizes currently used techniques for simulation and computer-aided design in electron and ion beam optics. Topics covered include: field computation, methods for computing optical properties (including Paraxial Rays and Aberration Integrals, Differential Algebra and Direct Ray Tracing), simulation of Coulomb interactions, space charge effects in electron and ion sources, tolerancing, wave optical simulations and optimization. Simulation examples are presented for multipole aberration correctors, Wien filter monochromators, imaging energy filters, magnetic prisms, general curved axis systems and electron mirrors.

Processing method for high resolution monochromator

International Nuclear Information System (INIS)

Kiriyama, Koji; Mitsui, Takaya

2006-12-01

A processing method for high resolution monochromator (HRM) has been developed at Japanese Atomic Energy Agency/Quantum Beam Science Directorate/Synchrotron Radiation Research unit at SPring-8. For manufacturing a HRM, a sophisticated slicing machine and X-ray diffractometer have been installed for shaping a crystal ingot and orienting precisely the surface of a crystal ingot, respectively. The specification of the slicing machine is following; Maximum size of a diamond blade is φ 350mm in diameter, φ 38.1mm in the spindle diameter, and 2mm in thickness. A large crystal such as an ingot with 100mm in diameter, 200mm in length can be cut. Thin crystal samples such as a wafer can be also cut using by another sample holder. Working distance of a main shaft with the direction perpendicular to working table in the machine is 350mm at maximum. Smallest resolution of the main shaft with directions of front-and-back and top-and-bottom are 0.001mm read by a digital encoder. 2mm/min can set for cutting samples in the forward direction. For orienting crystal faces relative to the blade direction adjustment, a one-circle goniometer and 2-circle segment are equipped on the working table in the machine. A rotation and a tilt of the stage can be done by manual operation. Digital encoder in a turn stage is furnished and has angle resolution of less than 0.01 degrees. In addition, a hand drill as a supporting device for detailed processing of crystal is prepared. Then, an ideal crystal face can be cut from crystal samples within an accuracy of about 0.01 degrees. By installation of these devices, a high energy resolution monochromator crystal for inelastic x-ray scattering and a beam collimator are got in hand and are expected to be used for nanotechnology studies. (author)

Plane grating monochromators for synchrotron radiation

International Nuclear Information System (INIS)

Howells, M.R.

1979-01-01

The general background and theoretical basis of plane grating monochromators (PGM's) is reviewed and the particular case of grazing incidence PGM's suitable for use with synchrotron radiation is considered in detail. The theory of reflection filtering is described and the problem of the finite source distance is shown to be of special importance with high brightness storage rings. The design philosophy of previous instruments is discussed and a new scheme proposed, aimed at dealing with the problem of the finite source distance. This scheme, involving a parabolic collimating mirror fabricated by diamond turning, is considered in the context of Wolter-type telescopes and microscopes. Some practical details concerning an instrument presently under construction using the new design are presented

Thermal bump removal of a crystal monochromator by designing an optimal shape

Energy Technology Data Exchange (ETDEWEB)

Micha, Jean-Sébastien, E-mail: micha@esrf.fr [CRG-IF BM32 Beamline, ESRF, 6 rue J. Horowitz, BP 220, 38043 Grenoble (France); UMR SPrAM 5819, CEA-Grenoble/INAC/SPrAM, 17 avenue des Martyrs, 38054 Grenoble Cedex 9 (France); Geaymond, Olivier [CRG-IF BM32 Beamline, ESRF, 6 rue J. Horowitz, BP 220, 38043 Grenoble (France); Institut Néel, CNRS, 25 avenue des Martyrs, 38054 Grenoble Cedex 9 (France); Rieutord, Francois [CRG-IF BM32 Beamline, ESRF, 6 rue J. Horowitz, BP 220, 38043 Grenoble (France); CEA-Grenoble/INAC/NRS, 17 avenue des Martyrs, 38054 Grenoble Cedex 9 (France)

2013-05-11

Thermal bump arising at illuminated area of a water cooled monochromator crystal can be considerably reduced by designing an appropriate shape. Temperature and deformation have been simulated by finite element analysis (FEA) computations as a function of few geometrical parameters describing the shape of the crystal. As a result, a new crystal shape has been found which optimizes the throughput of a double crystals monochromator (DCM). Performances of the initial rectangular crystal and the new designed crystal predicted by FEA-based calculations and measured during experimental tests on a synchrotron beamline are reported. General design principles to overcome heat load issues and the objective function using the slope errors derived from FEA results are detailed. Current and foreseen performances at higher load are presented. Finally, advantages and limits of this simple-to-design and cheap solution are discussed.

A high throughput 2 m normal incidence monochromator for SURF-II

International Nuclear Information System (INIS)

Ederer, D.L.; Cole, B.E.; West, J.B.

1980-01-01

The high intrinsic brightness of the circulating electron beam at SURF-II is used as the entrance slit for a two-meter normal incidence monochromator. A typical beam size for the electron beam is 100 μm high by 2 mm wide yielding an obserbed resolution of 0.4 Angstroem with a 200 μm exit slit and a 2400 lines/mm grating. The instrument accepts a beam with a 65 mrad horizontal divergence and a 10 mrad vertical divergence. A plane pre-mirror used near normal incidence reflects the incoming radiation onto the 2 m grating; this combination provides a horizontal exit beam, and enables the experiment to be located three meters from the orbit tangent point. With magnesium fluoride coated aluminium optics a flux of 2 x 10'' photon/s x Angstroem at 1200 Angstroem is observed with a 10 mA circulating current. A flux of 5 x 10 10 photon/s x Angstroem at 600 Angstroem is obserbed with an osmium coated grating and a 10 mA circulating current. Sample spectra of the angle-resolved photoelectron spectrum of CO are presented. (orig.)

Performance of synchrotron x-ray monochromators under heat load: How reliable are the predictions?

International Nuclear Information System (INIS)

Freund, A.K.; Hoszowska, J.; Migliore, J.-S.; Mocella, V.; Zhang, L.; Ferrero, C.

2000-01-01

With the ongoing development of insertion devices with smaller gaps the heat load generated by modern synchrotron sources increases continuously. To predict the overall performance of experiments on beam lines it is of crucial importance to be able to predict the efficiency of x-ray optics and in particular that of crystal monochromators. We report on a detailed comparison between theory and experiment for a water-cooled silicon crystal exposed to bending magnet radiation of up to 237 W total power and 1.3 W/mm2 power density. The thermal deformation has been calculated by the code ANSYS and its output has been injected into a finite difference code based on the Takagi-Taupin diffraction theory for distorted crystals. Several slit settings, filters and reflection orders were used to vary the geometrical conditions and the x-ray penetration depth in the crystal. In general, good agreement has been observed between the calculated and the observed values for the rocking curve width

A method for evaluating image quality of monochrome and color displays based on luminance by use of a commercially available color digital camera

Energy Technology Data Exchange (ETDEWEB)

Tokurei, Shogo, E-mail: shogo.tokurei@gmail.com, E-mail: junjim@med.kyushu-u.ac.jp [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan and Department of Radiology, Yamaguchi University Hospital, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Morishita, Junji, E-mail: shogo.tokurei@gmail.com, E-mail: junjim@med.kyushu-u.ac.jp [Department of Health Sciences, Faculty of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582 (Japan)

2015-08-15

Purpose: The aim of this study is to propose a method for the quantitative evaluation of image quality of both monochrome and color liquid-crystal displays (LCDs) using a commercially available color digital camera. Methods: The intensities of the unprocessed red (R), green (G), and blue (B) signals of a camera vary depending on the spectral sensitivity of the image sensor used in the camera. For consistent evaluation of image quality for both monochrome and color LCDs, the unprocessed RGB signals of the camera were converted into gray scale signals that corresponded to the luminance of the LCD. Gray scale signals for the monochrome LCD were evaluated by using only the green channel signals of the camera. For the color LCD, the RGB signals of the camera were converted into gray scale signals by employing weighting factors (WFs) for each RGB channel. A line image displayed on the color LCD was simulated on the monochrome LCD by using a software application for subpixel driving in order to verify the WF-based conversion method. Furthermore, the results obtained by different types of commercially available color cameras and a photometric camera were compared to examine the consistency of the authors’ method. Finally, image quality for both the monochrome and color LCDs was assessed by measuring modulation transfer functions (MTFs) and Wiener spectra (WS). Results: The authors’ results demonstrated that the proposed method for calibrating the spectral sensitivity of the camera resulted in a consistent and reliable evaluation of the luminance of monochrome and color LCDs. The MTFs and WS showed different characteristics for the two LCD types owing to difference in the subpixel structure. The MTF in the vertical direction of the color LCD was superior to that of the monochrome LCD, although the WS in the vertical direction of the color LCD was inferior to that of the monochrome LCD as a result of luminance fluctuations in RGB subpixels. Conclusions: The authors�

A new transmission based monochromator for energy-selective neutron imaging at the ICON beamline

International Nuclear Information System (INIS)

Peetermans, S.; Tamaki, M.; Hartmann, S.; Kaestner, A.; Morgano, M.; Lehmann, E.H.

2014-01-01

A new type of monochromator has been developed for energy-selective neutron imaging at continuous sources. It combines the use of a mechanical neutron velocity selector with pyrolytic graphite crystals of different mosaicity. The beam can be monochromatized to similar levels as a standard double crystal monochromator. It can flexibly produce different desired spectral shapes, even an asymmetric one. Intrinsically, no higher order contamination of the spectrum is present. Working with the transmitted beam, the beam divergence (and thus the spatial resolution) is uncompromised. The device has been calibrated, characterized and its performance demonstrated with the measurement of Bragg edges for iron and lead, resolving them more sharply than if solely a mechanical velocity selector was used

Radiation-shielded double crystal X-ray monochromator for JET

International Nuclear Information System (INIS)

Barnsley, R.; Morsi, H.W.; Rupprecht, G.; Kaellne, E.

1989-01-01

A double crystal X-ray monochromator for absolute wavelength and intensity measurements with very effective shielding of its detector against neutrons and hard X-rays was brought into operation at JET. Fast wavelength scans were taken of impurity line radiation in the wavelength region from about 0.1 nm to 2.3 nm, and monochromatic as well as spectral line scans, for different operational modes of JET. (author) 5 refs., 4 figs

Mechanical design and performance evaluation for plane grating monochromator in a soft X-ray microscopy beamline at SSRF.

Science.gov (United States)

Gong, Xuepeng; Lu, Qipeng

2015-01-01

A new monochromator is designed to develop a high performance soft X-ray microscopy beamline at Shanghai Synchrotron Radiation Facility (SSRF). But owing to its high resolving power and high accurate spectrum output, there exist many technical difficulties. In the paper presented, as two primary design targets for the monochromator, theoretical energy resolution and photon flux of the beamline are calculated. For wavelength scanning mechanism, primary factors affecting the rotary angle errors are presented, and the measuring results are 0.15'' and 0.17'' for plane mirror and plane grating, which means that it is possible to provide sufficient scanning precision to specific wavelength. For plane grating switching mechanism, the repeatabilities of roll, yaw and pitch angles are 0.08'', 0.12'' and 0.05'', which can guarantee the high accurate switch of the plane grating effectively. After debugging, the repeatability of light spot drift reaches to 0.7'', which further improves the performance of the monochromator. The commissioning results show that the energy resolving power is higher than 10000 at Ar L-edge, the photon flux is higher than 1 × 108 photons/sec/200 mA, and the spatial resolution is better than 30 nm, demonstrating that the monochromator performs very well and reaches theoretical predictions.

A new flexible monochromator setup for quick scanning x-ray absorption spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Stoetzel, J.; Luetzenkirchen-Hecht, D.; Frahm, R. [Fachbereich C, Physik, Bergische Universitaet Wuppertal, Gaussstr. 20, 42097 Wuppertal (Germany)

2010-07-15

A new monochromator setup for quick scanning x-ray absorption spectroscopy in the subsecond time regime is presented. Novel driving mechanics allow changing the energy range of the acquired spectra by remote control during data acquisition for the first time, thus dramatically increasing the flexibility and convenience of this method. Completely new experiments are feasible due to the fact that time resolution, edge energy, and energy range of the acquired spectra can be changed continuously within seconds without breaking the vacuum of the monochromator vessel and even without interrupting the measurements. The advanced mechanics are explained in detail and the performance is characterized with x-ray absorption spectra of pure metal foils. The energy scale was determined by a fast and accurate angular encoder system measuring the Bragg angle of the monochromator crystal with subarcsecond resolution. The Bragg angle range covered by the oscillating crystal can currently be changed from 0 deg. to 3.0 deg. within 20 s, while the mechanics are capable to move with frequencies of up to ca. 35 Hz, leading to ca. 14 ms/spectrum time resolution. A new software package allows performing programmed scan sequences, which enable the user to measure stepwise with alternating parameters in predefined time segments. Thus, e.g., switching between edges scanned with the same energy range is possible within one in situ experiment, while also the time resolution can be varied simultaneously. This progress makes the new system extremely user friendly and efficient to use for time resolved x-ray absorption spectroscopy at synchrotron radiation beamlines.

Measurement & Minimization of Mount Induced Strain on Double Crystal Monochromator Crystals

Science.gov (United States)

Kelly, J.; Alcock, S. G.

2013-03-01

Opto-mechanical mounts can cause significant distortions to monochromator crystals and mirrors if not designed or implemented carefully. A slope measuring profiler, the Diamond-NOM [1], was used to measure the change in tangential slope as a function of crystal clamping configuration and load. A three point mount was found to exhibit the lowest surface distortion (Diamond Light Source.

Mechanical design aspects of a soft X-ray plane grating monochromator

Czech Academy of Sciences Publication Activity Database

Vašina, R.; Kolařík, V.; Doležel, P.; Mynář, M.; Vondráček, Martin; Cháb, Vladimír; Slezák, Jiří; Comicioli, C.; Prince, K. C.

467-468, 467-468 (2001), s. 561-564 ISSN 0168-9002 R&D Projects: GA ČR GV202/98/K002 Grant - others:-(XE) CIPA-CT94-0217 Institutional research plan: CEZ:AV0Z2041904 Keywords : synchrotron radiation * monochromator * plane grating Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.026, year: 2001

Advances in thin film diffraction instrumentation by X-ray optics

International Nuclear Information System (INIS)

Haase, A.

1996-01-01

The structural characterisation of thin films requires a parallel X-ray beam of high intensity. Parallel beam geometry is commonly used in high resolution and single crystal experiments, but also in the field of X-ray diffraction for polycrystalline material (e.g. in phase, texture and stress analysis). For grazing incidence diffraction (GID), the use of small slits on the primary side and of long soller slits with a flat monochromator on the secondary side is standard. New optical elements have been introduced with polychromatic or monochromatic radiation. By means of different applications the results are compared with those of classical beam optics. X-ray fiber optics utilize total external reflection of X-rays on smooth surfaces. Effects of monochromatization are presented. In many fields of application, fiber optics may replace conventional collimators. The use of primary and secondary channel cut crystals can also produce a high parallel monochromatic X-ray beam. A parabolically bent graded multilayer produces a monochromatic parallel beam of high intensity. Compared with classical Bragg-Brentano (focussing) geometry, excellent results have been obtained, especially for samples with an irregular shape. In combination with a channel cut monochromator there is a substantial gain in intensity leading to an increase of the dynamic intensity range of rocking curves

Advances in thin film diffraction instrumentation by X-ray optics

Energy Technology Data Exchange (ETDEWEB)

Haase, A [Rich. Seifert and Co., Analytical X-ray Systems, Ahrensburg (Germany)

1996-09-01

The structural characterisation of thin films requires a parallel X-ray beam of high intensity. Parallel beam geometry is commonly used in high resolution and single crystal experiments, but also in the field of X-ray diffraction for polycrystalline material (e.g. in phase, texture and stress analysis). For grazing incidence diffraction (GID), the use of small slits on the primary side and of long soller slits with a flat monochromator on the secondary side is standard. New optical elements have been introduced with polychromatic or monochromatic radiation. By means of different applications the results are compared with those of classical beam optics. X-ray fiber optics utilize total external reflection of X-rays on smooth surfaces. Effects of monochromatization are presented. In many fields of application, fiber optics may replace conventional collimators. The use of primary and secondary channel cut crystals can also produce a high parallel monochromatic X-ray beam. A parabolically bent graded multilayer produces a monochromatic parallel beam of high intensity. Compared with classical Bragg-Brentano (focussing) geometry, excellent results have been obtained, especially for samples with an irregular shape. In combination with a channel cut monochromator there is a substantial gain in intensity leading to an increase of the dynamic intensity range of rocking curves.

Higher harmonics suppression in Fe/Si polarizing neutron monochromators

Energy Technology Data Exchange (ETDEWEB)

Merkel, D.G., E-mail: merkel.daniel@wigner.mta.hu [Wigner Research Centre for Physics, P.O. Box 49, H-1525, Budapest (Hungary); Nagy, B.; Sajti, Sz.; Szilágyi, E. [Wigner Research Centre for Physics, P.O. Box 49, H-1525, Budapest (Hungary); Kovács-Mezei, R. [Mirrotron Ltd. Konkoly-Thege M. út 29-33, H-1121 Budapest (Hungary); Bottyán, L. [Wigner Research Centre for Physics, P.O. Box 49, H-1525, Budapest (Hungary)

2013-03-11

The reflected neutron beam originating from a crystal monochromator contains higher order wavelength contributions. Multilayer mirror structures with various custom reflectivity curves including monochromatization and/or polarization of the neutron beam constitute a challenge in modern neutron optics. In this work, we present the study of three types of magnetron-sputtered Fe/Si layer structures with the purpose of higher harmonic suppression. First, an approximately sinusoidal profile was achieved directly by carefully controlling the evaporation parameters during sputtering that leads to first-Bragg-peak reflectivity and polarizing efficiency of R{sub c}=82% and P=97%, respectively. Second, a random, quasi-periodic distribution of the layer thicknesses was implemented, in which the layer structure of the structure was derived from a fit to a prescribed simulated spectrum. This solution resulted in R{sub c}=92% and P=88%. Third, a structure of Fe/Si layers with rounded scattering length profile was constructed starting with a step-like profile and applying 350 keV Ne{sup +} irradiation of 0, 0.5, 1.0, 2.7 and 27×10{sup 15}/cm{sup 2} fluence. Disregarding the highest fluence, the increasing fluence improved the monochromatization (decreasing the intensity of higher order reflections from a total of 11.1% to 2.2% and that of the first Bragg peak from 80% to 70%) and increased the polarizing efficiency from P=79% to 91%). In none of the above structures was a contrast matching agent added to the constituents.

Image quality evaluation of medical color and monochrome displays using an imaging colorimeter

Science.gov (United States)

Roehrig, Hans; Gu, Xiliang; Fan, Jiahua

2012-10-01

The purpose of this presentation is to demonstrate the means which permit examining the accuracy of Image Quality with respect to MTF (Modulation Transfer Function) and NPS (Noise Power Spectrum) of Color Displays and Monochrome Displays. Indications were in the past that color displays could affect the clinical performance of color displays negatively compared to monochrome displays. Now colorimeters like the PM-1423 are available which have higher sensitivity and color accuracy than the traditional cameras like CCD cameras. Reference (1) was not based on measurements made with a colorimeter. This paper focuses on the measurements of physical characteristics of the spatial resolution and noise performance of color and monochrome medical displays which were made with a colorimeter and we will after this meeting submit the data to an ROC study so we have again a paper to present at a future SPIE Conference.Specifically, Modulation Transfer Function (MTF) and Noise Power Spectrum (NPS) were evaluated and compared at different digital driving levels (DDL) between the two medical displays. This paper focuses on the measurements of physical characteristics of the spatial resolution and noise performance of color and monochrome medical displays which were made with a colorimeter and we will after this meeting submit the data to an ROC study so we have again a paper to present at a future Annual SPIE Conference. Specifically, Modulation Transfer Function (MTF) and Noise Power Spectrum (NPS) were evaluated and compared at different digital driving levels (DDL) between the two medical displays. The Imaging Colorimeter. Measurement of color image quality needs were done with an imaging colorimeter as it is shown below. Imaging colorimetry is ideally suited to FPD measurement because imaging systems capture spatial data generating millions of data points in a single measurement operation. The imaging colorimeter which was used was the PM-1423 from Radiant Imaging. It uses

Characterisation of a Sr-90 based electron monochromator

CERN Document Server

Arfaoui, S; CERN; Casella, C; ETH Zurich

2015-01-01

This note describes the characterisation of an energy filtered Sr-90 source to be used in laboratory studies that require Minimum Ionising Particles (MIP) with a kinetic energy of up to approx. 2 MeV. The energy calibration was performed with a LYSO scintillation crystal read out by a digital Silicon Photomultiplier (dSiPM). The LYSO/dSiPM set-up was pre-calibrated using a Na-22 source. After introducing the motivation behind the usage of such a device, this note presents the principle and design of the electron monochromator as well as its energy and momentum characterisation.

Performance limits of direct cryogenically cooled silicon monochromators - experimental results at the APS

International Nuclear Information System (INIS)

Lee, W.-K.; Fernandez, P.; Mills, D.M.

2000-01-01

The successful use of cryogenically cooled silicon monochromators at third-generation synchrotron facilities is well documented. At the Advanced Photon Source (APS) it has been shown that, at 100 mA operation with the standard APS undulator A, the cryogenically cooled silicon monochromator performs very well with minimal (<2 arcsec) or no observable thermal distortions. However, to date there has not been any systematic experimental study on the performance limits of this approach. This paper presents experimental results on the performance limits of these directly cooled crystals. The results show that if the beam is limited to the size of the radiation central cone then, at the APS, the crystal will still perform well at twice the present 100 mA single 2.4 m-long 3.3 cm-period undulator heat load. However, the performance would degrade rapidly if a much larger incident white-beam size is utilized

Aberration corrected and monochromated environmental transmission electron microscopy: challenges and prospects for materials science

DEFF Research Database (Denmark)

Hansen, Thomas Willum; Wagner, Jakob Birkedal; Dunin-Borkowski, Rafal E.

2010-01-01

The latest generation of environmental transmission electron microscopes incorporates aberration correctors and monochromators, allowing studies of chemical reactions and growth processes with improved spatial resolution and spectral sensitivity. Here, we describe the performance of such an instr...

High heat load synchrotron optics

International Nuclear Information System (INIS)

Mills, D.M.

1993-01-01

Third generation synchrotron radiation sources currently being constructed worldwide will produce x-ray beams of unparalleled power and power density. These high heat fluxes coupled with the stringent dimensional requirements of the x-ray optical components pose a prodigious challenge to designers of x-ray optical elements, specifically x-ray mirrors and crystal monochromators. Although certain established techniques for the cooling of high heat flux components can be directly applied to this problem, the thermal management of high heat load x-ray optical components has several unusual aspects that may ultimately lead to unique solutions. This manuscript attempts to summarize the various approaches currently being applied to this undertaking and to point out the areas of research that require further development

The use of diffraction efficiency theory in the design of soft x-ray monochromators

International Nuclear Information System (INIS)

Padmore, H.A.; Martynov, V.; Hollis, K.; Mount Vernon Hospital, Northwood

1993-01-01

In general, the diffraction efficiency of gratings is limited by the constraints imposed by the type of geometry used to scan the photon energy. In the simplest example, the spherical grating monochromator (SGM), the deviation angle, the grating groove width and depth and the groove density are all constrained by considerations of the maximum photon energy and the tuning range for individual gratings. We have examined the case in which these parameters are unconstrained, resulting in predictions of the ultimate performance of lamellar type gratings for groove densities from 300 to 2400 1/mm for gold and nickel coatings. The differential method of Neviere et al was used for modeling the behavior of the gratings and justification is presented for this by rigorous comparison with measurements. The implications of these results for future monochromators based on a variable included angle geometry are discussed

Diamond double-crystal monochromator in Bragg geometry installed on BL-11XU at SPring-8

CERN Document Server

Marushita, M; Fukuda, T; Takahasi, M; Inami, T; Katayama, Y; Shiwaku, H; Mizuki, J

2001-01-01

We present here the feature of the diamond double-crystal monochromator in Bragg geometry installed on a standard undulator beamline at SPring-8. The crystal was manufactured by Sumitomo Electric Industries, Ltd., whose size was 8.6 mm (w) x3.5 mm (l) x0.35 mm (t) for the first crystal and 10 mm (w) x4.7 mm (l) x0.39 mm (t) for the second. The feature of the monochromator was tested by rocking curve measurements as a function of the total power and of the energy that impinged on the crystal. As a result, no significant increase of the full-width at half-maximum was observed up to a total power of 330 W on the first crystal. We discuss the experimental results with the comparison to the calculated FWHM with use of the beamline parameters.

Performance of the SURF-II high-throughput toroidal grating monochromator

International Nuclear Information System (INIS)

Kurtz, R.L.; Ederer, D.L.; Barth, J.; Stockbauer, R.

1988-01-01

The performance of the 'high-flux' toroidal grating monochromator (HFTGM) at the NBS SURF-II synchrotron storage ring is assessed. Two gratings are studied: One with a ruled profile and the other having a laminar profile. The laminar profile is shown to reduce substantially the intensity of higher-order diffracted light with only a small decrease in the intensity of the first order light. The dependence of the energy resolution as a function of the area of the grating illuminated is also discussed. (orig.)

Performances of synchrotron X-ray monochromators under heat load. Part 2. Application of the Takagi-Taupin diffraction theory

International Nuclear Information System (INIS)

Mocella, V.; Ferrero, C.; Freund, A.K.; Hoszowska, J.; Zhang, L.; Epelboin, Y.

2001-01-01

The aim of this work is to generate the rocking curves of monochromators exposed to heat load in synchrotron radiation beams with a computer code performing diffraction calculations based on the theory of Takagi and Taupin. The model study starts with the calculation of deformation by finite element analysis and from an accurate characterization of the incident wave and includes the simulation of the wavefront propagation between the first and the second crystal (analyzer) of a double crystal monochromator. A monochromatic plane wave as well as a polychromatic spherical wave approach is described. The theoretical predictions of both methods are compared with experimental data measured in Bragg geometry and critically discussed

Performances of synchrotron X-ray monochromators under heat load. Part 2. Application of the Takagi-Taupin diffraction theory

CERN Document Server

Mocella, V; Freund, A K; Hoszowska, J; Zhang, L; Epelboin, Y

2001-01-01

The aim of this work is to generate the rocking curves of monochromators exposed to heat load in synchrotron radiation beams with a computer code performing diffraction calculations based on the theory of Takagi and Taupin. The model study starts with the calculation of deformation by finite element analysis and from an accurate characterization of the incident wave and includes the simulation of the wavefront propagation between the first and the second crystal (analyzer) of a double crystal monochromator. A monochromatic plane wave as well as a polychromatic spherical wave approach is described. The theoretical predictions of both methods are compared with experimental data measured in Bragg geometry and critically discussed.

A fine adjustment mechanism of the second crystal in a double-crystal monochromator with a 3-PS parallel manipulator

International Nuclear Information System (INIS)

Cao Chongzhen; Gao, X.; Ma, P.; Yu, H.; Wang, F.; Huang, Y.; Liu, P.

2005-01-01

A novel fine adjustment mechanism of the second crystal in a double-crystal monochromator is put forward, which is based on a 3-PS parallel manipulator and the magnetic force. Not only is the principle of fine adjusting the pitch angle and the roll angle analyzed, but also optimization of the structure parameters of the permanent magnet, a key part of the fine adjustment mechanism. The fine adjustment mechanism with the 3-PS parallel manipulator has been applied successfully in the double-crystal monochromator of 4W1B beam line in the Beijing Synchrotron Radiation Facility (BSRF)

Raytracing, chopper, and guideline for double-headed Dragon monochromators (invited)

International Nuclear Information System (INIS)

Chen, C.T.

1992-01-01

The raytracing of the double-headed Dragon, a recently proposed monochromator for producing two simultaneous left and right circularly polarized soft x-ray beams, is presented. The energy resolution and wavelength of these two beams are confirmed to be identical, and the high performance of the original Dragon is found to be preserved in the double-headed configuration. A compact ultra-high vacuum compatible chopper for rapid alternation between left and right helicities is presented, and a guideline for collecting circularly polarized light from bending magnet sources is given

Ultrathin nondoped emissive layers for efficient and simple monochrome and white organic light-emitting diodes.

Science.gov (United States)

Zhao, Yongbiao; Chen, Jiangshan; Ma, Dongge

2013-02-01

In this paper, highly efficient and simple monochrome blue, green, orange, and red organic light emitting diodes (OLEDs) based on ultrathin nondoped emissive layers (EMLs) have been reported. The ultrathin nondoped EML was constructed by introducing a 0.1 nm thin layer of pure phosphorescent dyes between a hole transporting layer and an electron transporting layer. The maximum external quantum efficiencies (EQEs) reached 17.1%, 20.9%, 17.3%, and 19.2% for blue, green, orange, and red monochrome OLEDs, respectively, indicating the universality of the ultrathin nondoped EML for most phosphorescent dyes. On the basis of this, simple white OLED structures are also demonstrated. The demonstrated complementary blue/orange, three primary blue/green/red, and four color blue/green/orange/red white OLEDs show high efficiency and good white emission, indicating the advantage of ultrathin nondoped EMLs on constructing simple and efficient white OLEDs.

Development of a bent Laue beam-expanding double-crystal monochromator for biomedical X-ray imaging

International Nuclear Information System (INIS)

Martinson, Mercedes; Samadi, Nazanin; Belev, George; Bassey, Bassey; Lewis, Rob; Aulakh, Gurpreet; Chapman, Dean

2014-01-01

A bent Laue beam-expanding double-crystal monochromator was developed and tested at the Biomedical Imaging and Therapy beamline at the Canadian Light Source. The expander will reduce scanning time for micro-computed tomography and allow dynamic imaging that has not previously been possible at this beamline. The Biomedical Imaging and Therapy (BMIT) beamline at the Canadian Light Source has produced some excellent biological imaging data. However, the disadvantage of a small vertical beam limits its usability in some applications. Micro-computed tomography (micro-CT) imaging requires multiple scans to produce a full projection, and certain dynamic imaging experiments are not possible. A larger vertical beam is desirable. It was cost-prohibitive to build a longer beamline that would have produced a large vertical beam. Instead, it was proposed to develop a beam expander that would create a beam appearing to originate at a source much farther away. This was accomplished using a bent Laue double-crystal monochromator in a non-dispersive divergent geometry. The design and implementation of this beam expander is presented along with results from the micro-CT and dynamic imaging tests conducted with this beam. Flux (photons per unit area per unit time) has been measured and found to be comparable with the existing flat Bragg double-crystal monochromator in use at BMIT. This increase in overall photon count is due to the enhanced bandwidth of the bent Laue configuration. Whilst the expanded beam quality is suitable for dynamic imaging and micro-CT, further work is required to improve its phase and coherence properties

Design, Build & Test of a Double Crystal Monochromator for Beamlines I09 & I23 at the Diamond Light Source

Science.gov (United States)

Kelly, J.; Lee, T.; Alcock, S.; Patel, H.

2013-03-01

A high stability Double Crystal Monochromator has been developed at The Diamond Light Source for beamlines I09 and I23. The design specification was a cryogenic, fixed exit, energy scanning monochromator, operating over an energy range of 2.1 - 25 keV using a Si(111) crystal set. The novel design concepts are the direct drive, air bearing Bragg axis, low strain crystal mounts and the cooling scheme. The instrument exhibited superb stability and repeatability on the B16 Test Beamline. A 20 keV Si(555), 1.4 μrad rocking curve was demonstrated. The DCM showed good stability without any evidence of vibration or Bragg angle nonlinearity.

Design and fabrication of an active polynomial grating for soft-X-ray monochromators and spectrometers

CERN Document Server

Chen, S J; Perng, S Y; Kuan, C K; Tseng, T C; Wang, D J

2001-01-01

An active polynomial grating has been designed for use in synchrotron radiation soft-X-ray monochromators and spectrometers. The grating can be dynamically adjusted to obtain the third-order-polynomial surface needed to eliminate the defocus and coma aberrations at any photon energy. Ray-tracing results confirm that a monochromator or spectrometer based on this active grating has nearly no aberration limit to the overall spectral resolution in the entire soft-X-ray region. The grating substrate is made of a precisely milled 17-4 PH stainless steel parallel plate, which is joined to a flexure-hinge bender shaped by wire electrical discharge machining. The substrate is grounded into a concave cylindrical shape with a nominal radius and then polished to achieve a roughness of 0.45 nm and a slope error of 1.2 mu rad rms. The long trace profiler measurements show that the active grating can reach the desired third-order polynomial with a high degree of figure accuracy.

Suppression of surface effect by using bent-perfect-crystal monochromator in residual strain scanning

Czech Academy of Sciences Publication Activity Database

Vrána, Miroslav; Mikula, Pavol

490/491, - (2005), s. 234-238 ISSN 0255-5476 R&D Projects: GA ČR GA202/03/0891; GA AV ČR KSK1010104 Institutional research plan: CEZ:AV0Z1048901 Keywords : neutron diffraction * residual strain scanning * bent monochromator Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.399, year: 2005

Design of an adaptive cooled first crystal for an X-ray monochromator

International Nuclear Information System (INIS)

Dezoret, D.; Marmoret, R.; Freund, A.K.; Kvick, AA.; Ravelet, R.

1994-01-01

We report here on the design of the first crystal in an x-ray monochromator for E.S.R.F. beam lines. This crystal is a thin silicon foil bonded to a cooled beryllium support. A system of piezoelectric actuators is used to counterbalance the deformations induced by synchrotron beams. This work was carried out by the C.E.A. in collaboration with the E.S.R.F. and the LASERDOT Company (Aerospatiale Group). (orig.)

Design of a high-efficiency grazing incidence monochromator with multilayer-coated laminar gratings for the 1-6 keV region

International Nuclear Information System (INIS)

Koike, Masato; Ishino, Masahiko; Sasai, Hiroyuki

2006-01-01

A grazing incidence objective monochromator consisting of a spherical mirror, a varied-line-spacing plane grating with multilayered coating, a movable plane multilayered mirror, and a fixed exit slit for the 1-6 keV region has been designed. The included angle at the grating was chosen to satisfy the grating equation and extended Bragg condition simultaneously. The aberration was corrected by means of a hybrid design method. A spectral resolving power of ∼600-∼6000 and a throughput of ∼2%-∼40% is expected for the monochromator when used in an undulator beamline

Bragg reflection transmission filters for variable resolution monochromators

International Nuclear Information System (INIS)

Chapman, D.

1989-01-01

There are various methods for improving the angular and spectral resolution of monochromator and analyzer systems. The novel system described here, though limited to higher x-ray energies (>20keV), is based on a dynamical effect occurring on the transmitted beam with a thin perfect crystal plate set in the Bragg reflection case. In the case of Bragg reflection from a perfect crystal, the incident beam is rapidly attenuated as it penetrates the crystal in the range of reflection. This extinction length is of the order of microns. The attenuation length, which determines the amount of normal transmission through the plate is generally much longer. Thus, in the range of the Bragg reflection the attenuation of the transmitted beam can change by several orders of magnitude with a small change in energy or angle. This thin crystal plate cuts a notch in the transmitted beam with a width equal to its Darwin width, thus acting as a transmission filter. When used in a non-dispersive mode with other monochromator crystals, the filter when set at the Bragg angle will reflect the entire Darwin width of the incident beam and transmit the wings of the incident beam distribution. When the element is offset in angle by some fraction of the Darwin width, the filter becomes useful in adjusting the angular width of the transmitted beam and removing a wing. Used in pairs with a symmetric offset, the filters can be used to continuously adjust the intrinsic angular divergence of the beam with good wing reduction. Instances where such filters may be useful are in improving the angular resolution of a small angle scattering camera. These filters may be added to a Bonse-Hart camera with one pair on the incident beam to reduce the intrinsic beam divergence and a second pair on the analyzer arm to improve the analyzer resolution. 2 refs., 3 Figs

A new gradient monochromator for the IN13 back-scattering spectrometer

International Nuclear Information System (INIS)

Ciampolini, L.; Bove, L.E.; Mondelli, C.; Alianelli, L.; Labbe-Lavigne, S.; Natali, F.; Bee, M.; Deriu, A.

2005-01-01

We present new McStas simulations of the back-scattering thermal neutron spectrometer IN13 to evaluate the advantages of a new temperature gradient monochromator relative to a conventional one. The simulations show that a flux gain up to a factor 7 can be obtained with just a 10% loss in energy resolution and a 20% increase in beam spot size at the sample. The results also indicate that a moderate applied temperature gradient (ΔT∼16K) is sufficient to obtain this significant flux gain. n

Nano-fabrication of diffractive optics for soft X-ray and atom beam focusing

International Nuclear Information System (INIS)

Rehbein, S.

2002-01-01

Nano-structuring processes are described for manufacturing diffractive optics for the condenser-monochromator set-up of the transmission X-ray microscope (TXM) and for the scanning transmission X-ray microscope (STXM) at the BESSY II electron storage ring in Berlin. Furthermore, a process for manufacturing free-standing nickel zone plates for helium atom beam focusing experiments is presented. (author)

High-resolution monochromated electron energy-loss spectroscopy of organic photovoltaic materials.

Science.gov (United States)

Alexander, Jessica A; Scheltens, Frank J; Drummy, Lawrence F; Durstock, Michael F; Hage, Fredrik S; Ramasse, Quentin M; McComb, David W

2017-09-01

Advances in electron monochromator technology are providing opportunities for high energy resolution (10 - 200meV) electron energy-loss spectroscopy (EELS) to be performed in the scanning transmission electron microscope (STEM). The energy-loss near-edge structure in core-loss spectroscopy is often limited by core-hole lifetimes rather than the energy spread of the incident illumination. However, in the valence-loss region, the reduced width of the zero loss peak makes it possible to resolve clearly and unambiguously spectral features at very low energy-losses (photovoltaics (OPVs): poly(3-hexlythiophene) (P3HT), [6,6] phenyl-C 61 butyric acid methyl ester (PCBM), copper phthalocyanine (CuPc), and fullerene (C 60 ). Data was collected on two different monochromated instruments - a Nion UltraSTEM 100 MC 'HERMES' and a FEI Titan 3 60-300 Image-Corrected S/TEM - using energy resolutions (as defined by the zero loss peak full-width at half-maximum) of 35meV and 175meV, respectively. The data was acquired to allow deconvolution of plural scattering, and Kramers-Kronig analysis was utilized to extract the complex dielectric functions. The real and imaginary parts of the complex dielectric functions obtained from the two instruments were compared to evaluate if the enhanced resolution in the Nion provides new opto-electronic information for these organic materials. The differences between the spectra are discussed, and the implications for STEM-EELS studies of advanced materials are considered. Copyright © 2017 Elsevier B.V. All rights reserved.

Geometrical charged-particle optics

CERN Document Server

Rose, Harald

2012-01-01

This second edition is an extended version of the first edition of Geometrical Charged-Particle Optics. The updated reference monograph is intended as a guide for researchers and graduate students who are seeking a comprehensive treatment of the design of instruments and beam-guiding systems of charged particles and their propagation in electromagnetic fields. Wave aspects are included in this edition for explaining electron holography, the Aharanov-Bohm effect and the resolution of electron microscopes limited by diffraction. Several methods for calculating the electromagnetic field are presented and procedures are outlined for calculating the properties of systems with arbitrarily curved axis. Detailed methods are presented for designing and optimizing special components such as aberration correctors, spectrometers, energy filters monochromators, ion traps, electron mirrors and cathode lenses. In particular, the optics of rotationally symmetric lenses, quadrupoles, and systems composed of these elements are...

Principles for the comparison of the proportions of straylight present in monochromators of various types

International Nuclear Information System (INIS)

Glock, E.

1976-03-01

The origin and propagation of straylight in monochromators is investigated and an expression is derived for the ratio of the straylight and the effective spectral intensity within the exit slit. This expression, for a prescribed resolution and speed, permits to select the design involving the minimum of straylight which can be attained. (orig.) [de

Optimization of bent perfect Si(220)-crystal monochromator for residual strain/stress instrument - Part II

Czech Academy of Sciences Publication Activity Database

Moon, MK.; Em, Vt.; Lee, C.H.; Mikula, Pavol; Hong, KP; Choi, YH; Cheon, JK; Nam, UW; Kong, KN; Jin, KC

2005-01-01

Roč. 368, 1 2 3 4 (2005), s. 70-75 ISSN 0921-4526 R&D Projects: GA ČR(CZ) GA202/03/0891 Institutional research plan: CEZ:AV0Z10480505 Keywords : neutron monochromator * residual stress measurement * neutron diffractometers Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.796, year: 2005

Advantages of a monochromated transmission electron microscope for solid state physics

International Nuclear Information System (INIS)

Grogger, W.; Kothleitner, G.; Hofer, F.

2006-01-01

Full text: The characterization of nanostructured devices and functional materials at a nanometer scale is paramount for the understanding of their physical and chemical properties. Transmission electron microscopy (TEM) plays a central role, especially in terms of structural and chemical analysis on a nearly atomic scale. In particular, electron energy-loss spectrometry (EELS) can obtain information not only about the chemical composition of a thin sample, but also about chemical bonding and electronic structure (ionization edge fine structures) and optical properties (through valence loss EELS). Recent instrumental advances like monochromators for the electron gun in the TEM have made it possible to reduce the energy resolution to 0.15 eV at an acceleration voltage of 200 kV. Another strong point of the method lies in the combination with a fine electron probe (0.2 nm) which allows to record EELS spectra with high energy resolution and spatial resolution in the range of 1 nm. The improved energy resolution opens new possibilities for studying detailed electronic structure and bonding effects in solids such as transmission metal oxides. The experimental results will be compared with x-ray absorption spectroscopy and band structure calculations. A better energy-resolution is particularly important for measurements in the low loss region of the EELS spectrum which provides the information about the band gap and the dielectric function. We will highlight the potential of the method for studying metallic nanoparticles and semiconducting devices. Additionally, the influence of the intrinsic effects like core-hole and excited lifetime broadening and delocalization of the inelastically scattered electrons will be discussed. (author)

Performance of a high resolution monochromator for the vacuum ultraviolet radiation from the DORIS storage ring

International Nuclear Information System (INIS)

Saile, V.; Skibowski, M.; Steinmann, W.; Guertler, P.; Koch, E.E.; Kozevnikov, A.

1976-03-01

The unique properties of the DORIS storage ring at DESY as a synchrotron radiation source are exploited for high resolution spectroscopy in the vacuum ultraviolet. We describe a new experimental set up with a 3 meter normal incidence monochromator for wavelengths between 3,000 A to 300 A (4 [de

Design, Build and Test of a Double Crystal Monochromator for Beamlines I09 and I23 at the Diamond Light Source

International Nuclear Information System (INIS)

Kelly, J; Lee, T; Alcock, S; Patel, H

2013-01-01

A high stability Double Crystal Monochromator has been developed at The Diamond Light Source for beamlines I09 and I23. The design specification was a cryogenic, fixed exit, energy scanning monochromator, operating over an energy range of 2.1 – 25 keV using a Si(111) crystal set. The novel design concepts are the direct drive, air bearing Bragg axis, low strain crystal mounts and the cooling scheme. The instrument exhibited superb stability and repeatability on the B16 Test Beamline. A 20 keV Si(555), 1.4 μrad rocking curve was demonstrated. The DCM showed good stability without any evidence of vibration or Bragg angle nonlinearity.

Strain-free polished channel-cut crystal monochromators: a new approach and results

Science.gov (United States)

Kasman, Elina; Montgomery, Jonathan; Huang, XianRong; Lerch, Jason; Assoufid, Lahsen

2017-08-01

The use of channel-cut crystal monochromators has been traditionally limited to applications that can tolerate the rough surface quality from wet etching without polishing. We have previously presented and discussed the motivation for producing channel cut crystals with strain-free polished surfaces [1]. Afterwards, we have undertaken an effort to design and implement an automated machine for polishing channel-cut crystals. The initial effort led to inefficient results. Since then, we conceptualized, designed, and implemented a new version of the channel-cut polishing machine, now called C-CHiRP (Channel-Cut High Resolution Polisher), also known as CCPM V2.0. The new machine design no longer utilizes Figure-8 motion that mimics manual polishing. Instead, the polishing is achieved by a combination of rotary and linear functions of two coordinated motion systems. Here we present the new design of C-CHiRP, its capabilities and features. Multiple channel-cut crystals polished using the C-CHiRP have been deployed into several beamlines at the Advanced Photon Source (APS). We present the measurements of surface finish, flatness, as well as topography results obtained at 1-BM of APS, as compared with results typically achieved when polishing flat-surface monochromator crystals using conventional polishing processes. Limitations of the current machine design, capabilities and considerations for strain-free polishing of highly complex crystals are also discussed, together with an outlook for future developments and improvements.

Monochromaticity of optical radiation of Smith-Purcell generated by electron beam with 75 keV energy

International Nuclear Information System (INIS)

Adishchev, Yu.N.; Vukolov, A.V.; Karlovets, D.V.; Potylitsyn, A.P.; Kube, G.

2005-01-01

The monochromatism of the Smith-Purcell optical radiation generated by a 75-keV electron beam with a final emittance of ε = 0.65 x 10 -4 mm rad that passes over an optical grating with a period of D = 0.833 μm has been analyzed. It has been shown that the monochromatism (line width) of the Smith-Purcell radiation is determined not only by the angular aperture of a monochromator but also by the divergence of the electron beam [ru

Biological monochromator with a high flux in the visible spectrum

International Nuclear Information System (INIS)

Andre, M.; Guerin de Montgareuil, P.

1965-01-01

The object is to carry out research into photosynthesis using energetic illuminations similar to those employed with white light studies. The limitations are due mainly to the source. A comparison of various possible solutions has led to the choice of the sun used in conjunction with 4 large gratings. In an intermediate stage, a description is given of a medium-aperture monochromator with a 3 kW xenon arc and a single grating. With this set-up it is possible to obtain the following performance, given as an example; energy illumination, 1.3 mW/cm 2 over a surface of 50 cm 2 and for a bandwidth at half-height of 50 Angstroms. (authors) [fr

Pulse Compression of Phase-matched High Harmonic Pulses from a Time-Delay Compensated Monochromator

Directory of Open Access Journals (Sweden)

Ito Motohiko

2013-03-01

Full Text Available Pulse compression of single 32.6-eV high harmonic pulses from a time-delay compensated monochromator was demonstrated down to 11±3 fs by compensating the pulse front tilt. The photon flux was intensified up to 5.7×109 photons/s on target by implementing high harmonic generation under a phase matching condition in a hollow fiber used for increasing the interaction length.

Comparison of the commercial color LCD and the medical monochrome LCD using randomized object test patterns.

Directory of Open Access Journals (Sweden)

Jay Wu

Full Text Available Workstations and electronic display devices in a picture archiving and communication system (PACS provide a convenient and efficient platform for medical diagnosis. The performance of display devices has to be verified to ensure that image quality is not degraded. In this study, we designed a set of randomized object test patterns (ROTPs consisting of randomly located spheres with various image characteristics to evaluate the performance of a 2.5 mega-pixel (MP commercial color LCD and a 3 MP diagnostic monochrome LCD in several aspects, including the contrast, resolution, point spread effect, and noise. The ROTPs were then merged into 120 abdominal CT images. Five radiologists were invited to review the CT images, and receiver operating characteristic (ROC analysis was carried out using a five-point rating scale. In the high background patterns of ROTPs, the sensitivity performance was comparable between both monitors in terms of contrast and resolution, whereas, in the low background patterns, the performance of the commercial color LCD was significantly poorer than that of the diagnostic monochrome LCD in all aspects. The average area under the ROC curve (AUC for reviewing abdominal CT images was 0.717±0.0200 and 0.740±0.0195 for the color monitor and the diagnostic monitor, respectively. The observation time (OT was 145±27.6 min and 127±19.3 min, respectively. No significant differences appeared in AUC (p = 0.265 and OT (p = 0.07. The overall results indicate that ROTPs can be implemented as a quality control tool to evaluate the intrinsic characteristics of display devices. Although there is still a gap in technology between different types of LCDs, commercial color LCDs could replace diagnostic monochrome LCDs as a platform for reviewing abdominal CT images after monitor calibration.

Spectral tailoring of nanoscale EUV and soft x-ray multilayer optics

Science.gov (United States)

Huang, Qiushi; Medvedev, Viacheslav; van de Kruijs, Robbert; Yakshin, Andrey; Louis, Eric; Bijkerk, Fred

2017-03-01

Extreme ultraviolet and soft X-ray (XUV) multilayer optics have experienced significant development over the past few years, particularly on controlling the spectral characteristics of light for advanced applications like EUV photolithography, space observation, and accelerator- or lab-based XUV experiments. Both planar and three dimensional multilayer structures have been developed to tailor the spectral response in a wide wavelength range. For the planar multilayer optics, different layered schemes are explored. Stacks of periodic multilayers and capping layers are demonstrated to achieve multi-channel reflection or suppression of the reflective properties. Aperiodic multilayer structures enable broadband reflection both in angles and wavelengths, with the possibility of polarization control. The broad wavelength band multilayer is also used to shape attosecond pulses for the study of ultrafast phenomena. Narrowband multilayer monochromators are delivered to bridge the resolution gap between crystals and regular multilayers. High spectral purity multilayers with innovated anti-reflection structures are shown to select spectrally clean XUV radiation from broadband X-ray sources, especially the plasma sources for EUV lithography. Significant progress is also made in the three dimensional multilayer optics, i.e., combining micro- and nanostructures with multilayers, in order to provide new freedom to tune the spectral response. Several kinds of multilayer gratings, including multilayer coated gratings, sliced multilayer gratings, and lamellar multilayer gratings are being pursued for high resolution and high efficiency XUV spectrometers/monochromators, with their advantages and disadvantages, respectively. Multilayer diffraction optics are also developed for spectral purity enhancement. New structures like gratings, zone plates, and pyramids that obtain full suppression of the unwanted radiation and high XUV reflectance are reviewed. Based on the present achievement

Design of mirror and monochromator crystals for a high-resolution multiwavelength anomalous diffraction beam line on a bending magnet at the ESRF

International Nuclear Information System (INIS)

Roth, M.; Ferrer, J.; Simon, J.; Geissler, E.

1992-01-01

High intensity for diffraction experiments with high-energy resolution on an intense x-ray beam, like the bending magnet beam lines at the ESRF, requires a strict control of the curvature of the optical elements placed in the beam for geometrical focusing and for wavelength monochromatization. Unwanted curvatures can come from nonuniform and variable heating of the optical elements produced by the absorption of x rays. To design the CRG/D2AM beam line described in the accompanying paper, some new techniques were developed to control these effects based on geometrical, i.e., topological, considerations. (1) Cooling of the entrance mirror: longitudinal curvature can be strongly reduced by cooling the mirror from the sides (and not from the rear) and only near the reflecting surface (i.e., not over the whole lateral surface). The cooling can be achieved for instance with an isothermal liquid Ga eutectic bath. (2) Cooling of the first single-crystal Si monochromator: because of the size of the crystal, only cooling from the rear is conceivable in this case. It can be shown by calculation that the curvature due to the front-to-rear gradient can be exactly compensated by the thermal expansion of a metallic layer at the rear of the crystal, having a larger expansion coefficient than Si

X-ray optics for 50-100 keV undulator radiation using crystals and refractive lenses

International Nuclear Information System (INIS)

Shastri, S. D.; Mashayekhi, A.; Cremer, J. T.; Piestrup, M. A.

2003-01-01

Compound refractive lenses (CRLs) are effective for collimating or focusing high-energy x-ray beams (50 - 100 keV) and can be used in conjunction with crystal optics in a variety of configurations, as demonstrated at the 1-ID undulator beamline of the Advanced Photon Source. As a primary example, this article describes the quadrupling of the output flux when a collimating CRL, composed of cylindrical holes in aluminum, is inserted in between two successive monochromators -- a modest energy resolution premonochromator followed by a high-resolution monochromator. The premonochromator is a cryogenically cooled, divergence-preserving, bent double-Laue Si(111) crystal device delivering an energy width ΔE/E ∼ 10 -3 , sufficient for most experiments. The high-resolution monochromator is a four-reflection, flat Si(111) crystal system resembling two channel-cuts in a dispersive arrangement, reducing the bandwidth to ΔE/E -4 , as required for some applications. Tests with 67 keV and 81 keV photon energies show that the high-resolution monochromator, having a narrow angular acceptance of a few erad, exhibits, a four-fold throughput enhancement due to the insertion of a CRL which reduces the premonochromatized beam's vertical divergence from 29 erad to a few erad. The ability to focus high-energy x-rays with CRLs having long focal lengths (tens of meters) is also shown by creating a line focus of 70 - 90 μ m beam height in the beamline end-station with both the modest-energy-resolution and high-energy- resolution monochromatic x-rays

Diamond x-ray optics: Transparent, resilient, high-resolution, and wavefront preserving

International Nuclear Information System (INIS)

Shvyd’ko, Yuri; Blank, Vladimir; Terentyev, Sergey

2017-01-01

Diamond features a unique combination of outstanding physical properties perfect for numerous x-ray optics applications, where traditional materials such as silicon fail to perform. In the last two decades, impressive progress has been achieved in synthesizing diamond with high crystalline perfection, in manufacturing efficient, resilient, high-resolution, wavefront-preserving diamond optical components, and in implementing them in cutting-edge x-ray instruments. Diamond optics are essential for tailoring x-rays to the most challenging needs of x-ray research. Furthermore, they are becoming vital for the generation of fully coherent hard x-rays by seeded x-ray free-electron lasers. In this article, we review progress in manufacturing flawless diamond crystal components and their applications in diverse x-ray optical devices, such as x-ray monochromators, beam splitters, high-reflectance backscattering mirrors, lenses, phase plates, diffraction gratings, bent-crystal spectrographs, and windows.

Wake monochromator in asymmetric and symmetric Bragg and Laue geometry for self-seeding the European X-ray FEL

International Nuclear Information System (INIS)

Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni; Serkez, Svitozar; Tolkiehn, Martin

2013-01-01

We discuss the use of self-seeding schemes with wake monochromators to produce TW power, fully coherent pulses for applications at the dedicated bio-imaging beamline at the European X-ray FEL, a concept for an upgrade of the facility beyond the baseline previously proposed by the authors. We exploit the asymmetric and symmetric Bragg and Laue reflections (sigma polarization) in diamond crystal. Optimization of the bio-imaging beamline is performed with extensive start-to-end simulations, which also take into account effects such as the spatio-temporal coupling caused by the wake monochromator. The spatial shift is maximal in the range for small Bragg angles. A geometry with Bragg angles close to π/2 would be a more advantageous option from this viewpoint, albeit with decrease of the spectral tunability. We show that it will be possible to cover the photon energy range from 3 keV to 13 keV by using four different planes of the same crystal with one rotational degree of freedom.

Wake monochromator in asymmetric and symmetric Bragg and Laue geometry for self-seeding the European X-ray FEL

Energy Technology Data Exchange (ETDEWEB)

Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni; Serkez, Svitozar; Tolkiehn, Martin [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2013-01-15

We discuss the use of self-seeding schemes with wake monochromators to produce TW power, fully coherent pulses for applications at the dedicated bio-imaging beamline at the European X-ray FEL, a concept for an upgrade of the facility beyond the baseline previously proposed by the authors. We exploit the asymmetric and symmetric Bragg and Laue reflections (sigma polarization) in diamond crystal. Optimization of the bio-imaging beamline is performed with extensive start-to-end simulations, which also take into account effects such as the spatio-temporal coupling caused by the wake monochromator. The spatial shift is maximal in the range for small Bragg angles. A geometry with Bragg angles close to {pi}/2 would be a more advantageous option from this viewpoint, albeit with decrease of the spectral tunability. We show that it will be possible to cover the photon energy range from 3 keV to 13 keV by using four different planes of the same crystal with one rotational degree of freedom.

Rotation of X-ray polarization in the glitches of a silicon crystal monochromator.

Science.gov (United States)

Sutter, John P; Boada, Roberto; Bowron, Daniel T; Stepanov, Sergey A; Díaz-Moreno, Sofía

2016-08-01

EXAFS studies on dilute samples are usually carried out by collecting the fluorescence yield using a large-area multi-element detector. This method is susceptible to the 'glitches' produced by all single-crystal monochromators. Glitches are sharp dips or spikes in the diffracted intensity at specific crystal orientations. If incorrectly compensated, they degrade the spectroscopic data. Normalization of the fluorescence signal by the incident flux alone is sometimes insufficient to compensate for the glitches. Measurements performed at the state-of-the-art wiggler beamline I20-scanning at Diamond Light Source have shown that the glitches alter the spatial distribution of the sample's quasi-elastic X-ray scattering. Because glitches result from additional Bragg reflections, multiple-beam dynamical diffraction theory is necessary to understand their effects. Here, the glitches of the Si(111) four-bounce monochromator of I20-scanning just above the Ni  K edge are associated with their Bragg reflections. A fitting procedure that treats coherent and Compton scattering is developed and applied to a sample of an extremely dilute (100 micromolal) aqueous solution of Ni(NO 3 ) 2 . The depolarization of the wiggler X-ray beam out of the electron orbit is modeled. The fits achieve good agreement with the sample's quasi-elastic scattering with just a few parameters. The X-ray polarization is rotated up to ±4.3° within the glitches, as predicted by dynamical diffraction. These results will help users normalize EXAFS data at glitches.

Two strategies of lowering surface deformations of internally cooled X-ray optics

International Nuclear Information System (INIS)

Oberta, P.; Áč, V.; Hrdý, J.

2013-01-01

Internally cooled X-ray optics, like X-ray monochromators and reflecting X-ray mirrors, play a crucial role in defining a beamlines resolution, degree of coherence and flux. A great effort is invested in the development of these optical components. An important aspect of the functionality of high heat load optics is its cooling and its influence on surface deformation. The authors present a study of two different geometrical cooling approaches. Its influence on beam inhomogeneity due to the strain from the manufacturing process is presented. X-ray topographic images and FWHM measurements are presented. FEA simulations of cooling efficiency and surface deformations were performed. The best achieved results are under an enlargement of 0.4μrad of the measured rocking curve

The development of a colour liquid crystal display spatial light modulator and applications in polychromatic optical data processing

Science.gov (United States)

Aiken, John Charles

The development of a colour Spatial Light Modulator (SLM) and its application to optical information processing is described. Whilst monochrome technology has been established for many years, this is not the case for colour where commercial systems are unavailable. A main aspect of this study is therefore, how the use of colour can add an additional dimension to optical information processing. A well established route to monochrome system development has been the use of (black and white) liquid crystal televisions (LCTV) as SLM, providing useful performance at a low-cost. This study is based on the unique use of a colour display removed from a LCTV and operated as a colour SLM. A significant development has been the replacement of the original TV electronics operating the display with enhanced drive electronics specially developed for this application. Through a computer interface colour images from a drawing package or video camera can now be readily displayed on the LCD as input to an optical system. A detailed evaluation of the colour LCD optical properties, indicates that the new drive electronics have considerably improved the operation of the display for use as a colour SLM. Applications are described employing the use of colour in Fourier plane filtering, image correlation and speckle metrology. The SLM (and optical system) developed demonstrates, how the addition of colour has greatly enhanced its capabilities to implement principles of optical data processing, conventionally performed monochromatically. The hybrid combination employed, combining colour optical data processing with electronic techniques has resulted in a capable development system. Further development of the system using current colour LCDs and the move towards a portable system, is considered in the study conclusion.

Enhancement of the resolution of full-field optical coherence tomography by using a colour image sensor

Energy Technology Data Exchange (ETDEWEB)

Kalyanov, A L; Lychagov, V V; Smirnov, I V; Ryabukho, V P [N.G. Chernyshevsky Saratov State University, Saratov (Russian Federation)

2013-08-31

The influence of white balance in a colour image detector on the resolution of a full-field optical coherence tomograph (FFOCT) is studied. The change in the interference pulse width depending on the white balance tuning is estimated in the cases of a thermal radiation source (incandescent lamp) and a white light emitting diode. It is shown that by tuning white balance of the detector in a certain range, the FFOCT resolution can be increased by 20 % as compared to the resolution, attained with the use of a monochrome detector. (optical coherence tomography)

Enhancement of the resolution of full-field optical coherence tomography by using a colour image sensor

International Nuclear Information System (INIS)

Kalyanov, A L; Lychagov, V V; Smirnov, I V; Ryabukho, V P

2013-01-01

The influence of white balance in a colour image detector on the resolution of a full-field optical coherence tomograph (FFOCT) is studied. The change in the interference pulse width depending on the white balance tuning is estimated in the cases of a thermal radiation source (incandescent lamp) and a white light emitting diode. It is shown that by tuning white balance of the detector in a certain range, the FFOCT resolution can be increased by 20 % as compared to the resolution, attained with the use of a monochrome detector. (optical coherence tomography)

Determination Of Refractive Index And Reflectivity Of Thin Layer With Optical Absorption Method; PENENTUAN INDEKS BIAS DAN REFLEKTIVITAS LAPISAN TIPIS DENGAN METODA SERAPAN OPTIK

Energy Technology Data Exchange (ETDEWEB)

Hariyanto, Sigit; Budianto, Anwar; Subarkah,; Atmono, Trimarji [Yogyakarta Nuclear Research Center, National Nuclear Energy Agency, Yogyakarta (Indonesia)

1996-04-15

. The refractive index and reflectivity of ASi:H and Si Ox thin layer have been observed by optical absorption methods. Measurement has been done after the preparation of optical system which consists of a halogen lamp light source, monochromator, sample and light detector. The Monochromator output showed that measured halogen lamp spectrum light is between 470 nm -750 nm. The maximum voltage of halogen lamp is 220 Volt, the output light increases in intensity while the wave length increases. The inclination of intensity decrease at the wave length of 725 nm. The result of the calculation of refractive index varies in accordance with the wave length. The average refractive index of ASi:H is nf a = 1.753. The total reflectivity of air-thin layer-substrate is Rt a = 0.315. The refractive index of Si Ox sample is nf b2.182 and the total reflectivity is Rt b=O,514.

Evaluation of the Data-Ray DR96L 4 x 3 Aspect Ratio, 22-Inch Diagonal Flat Screen Monochrome CRT Monitor

National Research Council Canada - National Science Library

2001-01-01

.... Based on results of our evaluation of the third sample NIDL cannot certify the Data-Ray DR96L monochrome monitor as being suitable for suitable monoscopic or stereoscopic operation in IEC workstations...

A reflectivity profilometer for the optical characterisation of graded reflectivity mirrors in the 250 nm - 1100 nm spectral region

International Nuclear Information System (INIS)

Colucci, Alessandro; Nichelatti, Enrico

1998-04-01

It's developed the prototype of an instrument that can be used for the optical characterisation of graded reflectivity mirrors at any wavelength in the spectral region from 250 nm to 1100 nm. The instrument utilises a high-pressure Xe arc lamp as light source. Light is spectrally filtered by means of a grating monochromator. The sample is illuminated with an image of the monochromator exit slit. After reflection from the sample, this image is projected onto a 1024-elements charge-coupled device linear array driven by a digital frame board and interfaced with a personal computer. It's tested the instrument accuracy by comparing measurement results with the corresponding ones obtained by means of a laser scanning technique. Measurement Rms repeatability has been estimated to be approximately of 0.8% [it

A possibility of parallel and anti-parallel diffraction measurements on neu- tron diffractometer employing bent perfect crystal monochromator at the monochromatic focusing condition

Science.gov (United States)

Choi, Yong Nam; Kim, Shin Ae; Kim, Sung Kyu; Kim, Sung Baek; Lee, Chang-Hee; Mikula, Pavel

2004-07-01

In a conventional diffractometer having single monochromator, only one position, parallel position, is used for the diffraction experiment (i.e. detection) because the resolution property of the other one, anti-parallel position, is very poor. However, a bent perfect crystal (BPC) monochromator at monochromatic focusing condition can provide a quite flat and equal resolution property at both parallel and anti-parallel positions and thus one can have a chance to use both sides for the diffraction experiment. From the data of the FWHM and the Delta d/d measured on three diffraction geometries (symmetric, asymmetric compression and asymmetric expansion), we can conclude that the simultaneous diffraction measurement in both parallel and anti-parallel positions can be achieved.

Optics for coherent X-ray applications

Energy Technology Data Exchange (ETDEWEB)

Yabashi, Makina, E-mail: yabashi@spring8.or.jp [RIKEN SPring-8 Center, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Tono, Kensuke [Japan Synchrotron Radiation Research Institute (JASRI), Kouto 1-1-1, Sayo, Hyogo 679-5198 (Japan); Mimura, Hidekazu [The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8656 (Japan); Matsuyama, Satoshi; Yamauchi, Kazuto [Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Tanaka, Takashi; Tanaka, Hitoshi; Tamasaku, Kenji [RIKEN SPring-8 Center, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Ohashi, Haruhiko; Goto, Shunji [Japan Synchrotron Radiation Research Institute (JASRI), Kouto 1-1-1, Sayo, Hyogo 679-5198 (Japan); Ishikawa, Tetsuya [RIKEN SPring-8 Center, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan)

2014-08-27

Developments of optics for coherent X-ray applications and their role in diffraction-limited storage rings are described. Developments of X-ray optics for full utilization of diffraction-limited storage rings (DLSRs) are presented. The expected performance of DLSRs is introduced using the design parameters of SPring-8 II. To develop optical elements applicable to manipulation of coherent X-rays, advanced technologies on precise processing and metrology were invented. With propagation-based coherent X-rays at the 1 km beamline of SPring-8, a beryllium window fabricated with the physical-vapour-deposition method was found to have ideal speckle-free properties. The elastic emission machining method was utilized for developing reflective mirrors without distortion of the wavefronts. The method was further applied to production of diffraction-limited focusing mirrors generating the smallest spot size in the sub-10 nm regime. To enable production of ultra-intense nanobeams at DLSRs, a low-vibration cooling system for a high-heat-load monochromator and advanced diagnostic systems to characterize X-ray beam properties precisely were developed. Finally, new experimental schemes for combinative nano-analysis and spectroscopy realised with novel X-ray optics are discussed.

Rotation of X-ray polarization in the glitches of a silicon crystal monochromator

Energy Technology Data Exchange (ETDEWEB)

Sutter, John P.; Boada, Roberto; Bowron, Daniel T.; Stepanov, Sergey A.; Díaz-Moreno, Sofía

2016-07-06

EXAFS studies on dilute samples are usually carried out by collecting the fluorescence yield using a large-area multi-element detector. This method is susceptible to the `glitches' produced by all single-crystal monochromators. Glitches are sharp dips or spikes in the diffracted intensity at specific crystal orientations. If incorrectly compensated, they degrade the spectroscopic data. Normalization of the fluorescence signal by the incident flux alone is sometimes insufficient to compensate for the glitches. Measurements performed at the state-of-the-art wiggler beamline I20-scanning at Diamond Light Source have shown that the glitches alter the spatial distribution of the sample's quasi-elastic X-ray scattering. Because glitches result from additional Bragg reflections, multiple-beam dynamical diffraction theory is necessary to understand their effects. Here, the glitches of the Si(111) four-bounce monochromator of I20-scanning just above the Ni Kedge are associated with their Bragg reflections. A fitting procedure that treats coherent and Compton scattering is developed and applied to a sample of an extremely dilute (100 micromolal) aqueous solution of Ni(NO₃)₂. The depolarization of the wiggler X-ray beam out of the electron orbit is modeled. The fits achieve good agreement with the sample's quasi-elastic scattering with just a few parameters. The X-ray polarization is rotated up to ±4.3° within the glitches, as predicted by dynamical diffraction. These results will help users normalize EXAFS data at glitches.

Absolute calibration method for fast-streaked, fiber optic light collection, spectroscopy systems

International Nuclear Information System (INIS)

Johnston, Mark D.; Frogget, Brent; Oliver, Bryan Velten; Maron, Yitzhak; Droemer, Darryl W.; Crain, Marlon D.

2010-01-01

This report outlines a convenient method to calibrate fast (<1ns resolution) streaked, fiber optic light collection, spectroscopy systems. Such a system is used to collect spectral data on plasmas generated in the A-K gap of electron beam diodes fielded on the RITS-6 accelerator (8-12MV, 140-200kA). On RITS, light is collected through a small diameter (200 micron) optical fiber and recorded on a fast streak camera at the output of 1 meter Czerny-Turner monochromator (F/7 optics). To calibrate such a system, it is necessary to efficiently couple light from a spectral lamp into a 200 micron diameter fiber, split it into its spectral components, with 10 Angstroms or less resolution, and record it on a streak camera with 1ns or less temporal resolution.

Local Treatment for Monochrome Outdoor Painted Metal Sculptures: Assessing the suitability of conservation paints for retouching

OpenAIRE

van Basten, Nikki; Defeyt, Catherine; Rivenc, Rachel

2015-01-01

When outdoor painted sculptures get chipped, scratched or abraded, conservators might consider local retouching treatments as an option that would protect the exposed metal substrate and restore the aesthetic integrity, thus postponing a very costly and invasive overall repainting. Unfortunately, matching colour gloss and texture on large monochrome surfaces is always challenging. This paper reports on research undertaken to investigate some of the materials and application techniques that co...

Accuracy synthesis of T-shaped exit fixed mechanism in a double-crystal monochromator

International Nuclear Information System (INIS)

Wang Fengqin; Cao Chongzhen; Wang Jidai; Li Yushan; Gao Xueguan

2007-01-01

It is a key performance requirement for a double-crystal monochromator that the exit is fixed, and in order to improve the height accuracy of the exit in T-shaped exit fixed mechanism, the expression between the height of the exit and various original errors was put forward using geometrical analysis method. According to the independent action principle of original errors, accuracy synthesis of T-shaped exit fixed mechanism was studied by using the equal accuracy method, and the tolerance ranges of original errors were obtained. How to calculate the tolerance ranges of original errors was explained by giving an example. (authors)

A comparison of absolute calibrations of a radiation thermometer based on a monochromator and a tunable source

Energy Technology Data Exchange (ETDEWEB)

Keawprasert, T. [National Institute of Metrology Thailand, Pathum thani (Thailand); Anhalt, K.; Taubert, D. R.; Sperling, A.; Schuster, M.; Nevas, S. [Physikalisch Technische Bundesanstalt, Braunschweig and Berlin (Germany)

2013-09-11

An LP3 radiation thermometer was absolutely calibrated at a newly developed monochromator-based set-up and the TUneable Lasers in Photometry (TULIP) facility of PTB in the wavelength range from 400 nm to 1100 nm. At both facilities, the spectral radiation of the respective sources irradiates an integrating sphere, thus generating uniform radiance across its precision aperture. The spectral irradiance of the integrating sphere is determined via an effective area of a precision aperture and a Si trap detector, traceable to the primary cryogenic radiometer of PTB. Due to the limited output power from the monochromator, the absolute calibration was performed with the measurement uncertainty of 0.17 % (k= 1), while the respective uncertainty at the TULIP facility is 0.14 %. Calibration results obtained by the two facilities were compared in terms of spectral radiance responsivity, effective wavelength and integral responsivity. It was found that the measurement results in integral responsivity at the both facilities are in agreement within the expanded uncertainty (k= 2). To verify the calibration accuracy, the absolutely calibrated radiation thermometer was used to measure the thermodynamic freezing temperatures of the PTB gold fixed-point blackbody.

A comparison of absolute calibrations of a radiation thermometer based on a monochromator and a tunable source

International Nuclear Information System (INIS)

Keawprasert, T.; Anhalt, K.; Taubert, D. R.; Sperling, A.; Schuster, M.; Nevas, S.

2013-01-01

An LP3 radiation thermometer was absolutely calibrated at a newly developed monochromator-based set-up and the TUneable Lasers in Photometry (TULIP) facility of PTB in the wavelength range from 400 nm to 1100 nm. At both facilities, the spectral radiation of the respective sources irradiates an integrating sphere, thus generating uniform radiance across its precision aperture. The spectral irradiance of the integrating sphere is determined via an effective area of a precision aperture and a Si trap detector, traceable to the primary cryogenic radiometer of PTB. Due to the limited output power from the monochromator, the absolute calibration was performed with the measurement uncertainty of 0.17 % (k= 1), while the respective uncertainty at the TULIP facility is 0.14 %. Calibration results obtained by the two facilities were compared in terms of spectral radiance responsivity, effective wavelength and integral responsivity. It was found that the measurement results in integral responsivity at the both facilities are in agreement within the expanded uncertainty (k= 2). To verify the calibration accuracy, the absolutely calibrated radiation thermometer was used to measure the thermodynamic freezing temperatures of the PTB gold fixed-point blackbody

Experimental characterization of X-ray transverse coherence in the presence of beam transport optics

DEFF Research Database (Denmark)

Chubar, O.; Fluerasu, A.; Chu, Y.S.

2013-01-01

A simple Boron fiber based interference scheme [1] and other similar schemes are currently routinely used for X-ray coherence estimation at 3rd generation synchrotron radiation sources. If such a scheme is applied after a perfect monochromator and without any focusing / transport optics...... in the optical path, the interpretation of the measured interference pattern is relatively straightforward and can be done in terms of the basic parameters of the source [2]. However, if the interference scheme is used after some focusing optics, e.g. close to the X-ray beam waist, the visibility of fringes can...... be significantly affected by the new shape of the focused beam phase-space. At the same time, optical element imperfections still have a negative impact on the transverse coherence. In such situations, which are frequently encountered in experiments at beamlines, the quantitative interpretation of a measured...

Evaluation of material dispersion using a nanosecond optical pulse radiator.

Science.gov (United States)

Horiguchi, M; Ohmori, Y; Miya, T

1979-07-01

To study the material dispersion effects on graded-index fibers, a method for measuring the material dispersion in optical glass fibers has been developed. Nanosecond pulses in the 0.5-1.7-microm region are generated by a nanosecond optical pulse radiator and grating monochromator. These pulses are injected into a GeO(2)-P(2)0(5)-doped silica graded-index fiber. Relative time delay changes between different wavelengths are used to determine material dispersion, core glass refractive index, material group index, and optimum profile parameter of the graded-index fiber. From the measured data, the optimum profile parameter on the GeO(2)-P(2)O(5)-doped silica graded-index fiber could be estimated to be 1.88 at 1.27 microm of the material dispersion free wavelength region and 1.82 at 1.55 microm of the lowest-loss wavelength region in silica-based optical fiber waveguides.

Red sprites and blue jets: Thunderstorm-excited optical emissions in the stratosphere, mesosphere, and ionosphere

International Nuclear Information System (INIS)

Sentman, D.D.; Wescott, E.M.

1995-01-01

Recent low light level monochrome television observations obtained from the ground and from the space shuttle, and low light level color and monochrome television images obtained from aboard jet aircraft, have shown that intense lightning in mesoscale thunderstorm systems may excite at least two distinct types of optical emissions that together span the space between the tops of some thunderstorms and the ionosphere. The first of these emissions, dubbed ''sprites,'' are luminous red structures that typically span the altitude range 60--90 km, often with faint bluish tendrils dangling below. A second, rarer, type of luminous emission are ''blue jets'' that appear to spurt upward out of the anvil top in narrow cones to altitudes of 40--50 km at speeds of ∼100 km/s. In this paper the principal observational characteristics of sprites and jets are presented, and several proposed production mechanisms are reviewed. copyright 1995 American Institute of Physics

Characteristics of Pyrolytic Graphite as a Neutron Monochromator

International Nuclear Information System (INIS)

Adib, M.; Habib, N.; El-Mesiry, M.S.; Fathallah, M.

2011-01-01

Pyrolytic graphite (PG) has become nearly indispensable in neutron spectroscopy. Since the integrated reflectivity of the monochromatic neutrons from PG crystals cut along its c-axis is high within a wavelength band from 0.1 nm up to .65 nm. The monochromatic features of PG crystal is detailed in terms of the optimum mosaic spread, crystal thickness and reactor moderating temperature for efficient integrated neutron reflectivity within the wavelength band. A computer code Mono-PG has been developed to carry out the required calculations for the PG hexagonal close-packed structure. Calculation shows that, 2 mm thick of PG crystal having 0.30 FWHM on mosaic spread are the optimum parameters of PG crystal as a monochromator at selected neutron wavelength shorter than 2 nm. However, the integrated neutron intensity of 2nd and 3rd orders from thermal reactor flux is even higher than that of the 1st order one at neutron wavelengths longer than 2 nm. While, from cold reactor flux, integrated neutron intensity of the 1st order within the wavelength band from 0.25 up to 0.5 nm is higher than the 2nd and 3rd ones

First operation of an extended range grasshopper monochromator on the Aladdin storage ring

International Nuclear Information System (INIS)

Brown, F.C.

1986-01-01

First operation of a new extended range monochromator on the 1 GeV storage ring Aladdin is described. Curves are given of output flux as a function of photon energy for the 2 m and for the 5 m gratings as measured with an NBS diode. Relatively low background and flux up to 1500 eV is obtained using a 1200 line/mm 5 m holographic grating. Highly reproducible scans were obtained of the transmission of thin films including the carbon K and titanium L edges. This reproducibility and high throughput is in large part due to the small beam size and excellent stability of Aladdin. (orig.)

Stray light correction on array spectroradiometers for optical radiation risk assessment in the workplace

International Nuclear Information System (INIS)

Barlier-Salsi, A

2014-01-01

The European directive 2006/25/EC requires the employer to assess and, if necessary, measure the levels of exposure to optical radiation in the workplace. Array spectroradiometers can measure optical radiation from various types of sources; however poor stray light rejection affects their accuracy. A stray light correction matrix, using a tunable laser, was developed at the National Institute of Standards and Technology (NIST). As tunable lasers are very expensive, the purpose of this study was to implement this method using only nine low power lasers; other elements of the correction matrix being completed by interpolation and extrapolation. The correction efficiency was evaluated by comparing CCD spectroradiometers with and without correction and a scanning double monochromator device as reference. Similar to findings recorded by NIST, these experiments show that it is possible to reduce the spectral stray light by one or two orders of magnitude. In terms of workplace risk assessment, this spectral stray light correction method helps determine exposure levels, with an acceptable degree of uncertainty, for the majority of workplace situations. The level of uncertainty depends upon the model of spectroradiometers used; the best results are obtained with CCD detectors having an enhanced spectral sensitivity in the UV range. Thus corrected spectroradiometers require a validation against a scanning double monochromator spectroradiometer before using them for risk assessment in the workplace. (paper)

Stray light correction on array spectroradiometers for optical radiation risk assessment in the workplace.

Science.gov (United States)

Barlier-Salsi, A

2014-12-01

The European directive 2006/25/EC requires the employer to assess and, if necessary, measure the levels of exposure to optical radiation in the workplace. Array spectroradiometers can measure optical radiation from various types of sources; however poor stray light rejection affects their accuracy. A stray light correction matrix, using a tunable laser, was developed at the National Institute of Standards and Technology (NIST). As tunable lasers are very expensive, the purpose of this study was to implement this method using only nine low power lasers; other elements of the correction matrix being completed by interpolation and extrapolation. The correction efficiency was evaluated by comparing CCD spectroradiometers with and without correction and a scanning double monochromator device as reference. Similar to findings recorded by NIST, these experiments show that it is possible to reduce the spectral stray light by one or two orders of magnitude. In terms of workplace risk assessment, this spectral stray light correction method helps determine exposure levels, with an acceptable degree of uncertainty, for the majority of workplace situations. The level of uncertainty depends upon the model of spectroradiometers used; the best results are obtained with CCD detectors having an enhanced spectral sensitivity in the UV range. Thus corrected spectroradiometers require a validation against a scanning double monochromator spectroradiometer before using them for risk assessment in the workplace.

Design and fabrication of a Czerny-Turner monochromator-cum-spectrograph

International Nuclear Information System (INIS)

Murty, M.V.R.K.; Shukla, R.P.; Bhattacharya, S.S.; Krishnamurthy, G.

1987-01-01

The design and fabrication of a Czerny-Turner monochromator cum spectrograph is described. It consists of a classically ruled grating having 1200 grooves/mm. The collimator is a concave spherical mirror having a radius of curvature 1.025 metre while the focusing element is a concave spherical mirror of radius of curvature 0.925 metre. The design of two unequal radii of curvature for collimating and focusing mirrors is chosen to eliminate the chromatic aberration at the wavelength of 5000A. The linear reciprocal dispersion on the focal surface is about 8A/mm. The resolution of the instrument at the coma corrected wavelength i.e. 5000A is 0.1A. The resolution at the other wavelengths is limited by the residual chromatic aberration which increases linearly with wavelength on either side of the 5000A. Therefore the resolution at the wavelength 2000A and 8000A is about 0.2A. 7 figures. (author)

Studies Of The (n, γ) Reaction With A Neutron Monochromator

Energy Technology Data Exchange (ETDEWEB)

Kane, W. R.; Gardner, D.; Brown, T.; Kevey, A.; Mateosian, E. der; Emery, G. T.; Gelletly, W.; Mariscotti, M. A.J. [Brookhaven National Laboratory, Upton, Long Island, NY (United States); Schröder, I. [National Bureau of Standards, Washington, DC (United States)

1969-11-15

A crystal diffraction neutron monochromator has been constructed specifically for studies of the(n, γ) reaction. This equipment plays a complementary role to that of time-of-flight devices in providing a neutron beam with a full duty cycle at a given energy. This feature and the small target size, large geometrical efficiency for y-ray detection, and negligible fast neutron background afford advantages for certain classes of experiments. The useful energy range extends from 0.01 to 20 eV. Novel features of the equipment include a complete reliance upon precision angle encoders for setting arm and crystal angles, the employment of a liquid shield to facilitate the extraction of the diffracted neutron beam, and the use of air bearings to provide for the motion of the target, detection devices, and associated shielding. Results obtained on low energy resonances of {sup 139}La, {sup 189}Os, and {sup 235}U will be presented. (author)

Optimization of the bent perfect Si(311)-crystal monochromator for a residual strain/stress instrument at the HANARO reactor - Part I

Czech Academy of Sciences Publication Activity Database

Moon, MK; Lee, Ch.H.; Vyacheslav, T.; Mikula, Pavol

2005-01-01

Roč. 369, - (2005), s. 1-7 ISSN 0921-4526 R&D Projects: GA ČR GA202/03/0891 Institutional research plan: CEZ:AV0Z10480505 Keywords : neutron monochromator * residual stress measurement * neutron diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.796, year: 2005

At-wavelength metrology of x-ray optics at Diamond Light Source

Science.gov (United States)

Wang, Hongchang; Berujon, Sebastien; Sutter, John; Alcock, Simon G.; Sawhney, Kawal

2014-09-01

Modern, third-generation synchrotron radiation sources provide coherent and extremely bright beams of X-ray radiation. The successful exploitation of such beams depends to a significant extent on imperfections and misalignment of the optics employed on the beamlines. This issue becomes even more critical with the increasing use of active optics, and the desire to achieve diffraction-limited and coherence-preserving X-ray beams. In recent years, significant progress has been made to improve optic testing and optimization techniques, especially those using X-rays for so-called atwavelength metrology. These in-situ and at-wavelength metrology methods can be used not only to optimize the performance of X-ray optics, but also to correct and minimize the collective distortions of upstream beamline optics, including monochromators, and transmission windows. An overview of at-wavelength metrology techniques implemented at Diamond Light Source is presented, including grating interferometry and X-ray near-field speckle based techniques. Representative examples of the application of these techniques are also given, including in-situ and atwavelength calibration and optimization of: active, piezo bimorph mirrors; Kirkpatrick-Baez (KB) mirrors; and refractive optics such as compound refractive lenses.

Some thoughts on source monochromation and the implications for electron energy loss spectroscopy

CERN Document Server

Brydson, R; Brown, A

2003-01-01

We briefly outline the factors determining the intrinsic widths of features in electron energy loss near edge structure (ELNES) measured by electron energy loss spectroscopy (EELS) in the transmission electron microscope (TEM). We have made estimates of the differing contributions of both the initial and final state lifetime effects in the ELNES ionisation processes and also show how these may be combined with the instrumental energy resolution. We discuss the potential benefits of source monochromation for ELNES measurements via a comparison of these theoretical estimates with experimental spectra from the literature. We show that for certain core level excitations, solid state broadening mechanisms may be the fundamental limiting factor for resolving fine detail in ELNES. (orig.)

The sapphire backscattering monochromator at the Dynamics beamline P01 of PETRA III

Energy Technology Data Exchange (ETDEWEB)

Alexeev, P., E-mail: pavel.alexeev@desy.de [Deutsches Elektronen-Synchrotron DESY (Germany); Asadchikov, V. [Russian Academy of Sciences, A.V. Shubnikov Institute of Crystallography (Russian Federation); Bessas, D. [European Synchrotron Radiation Facility (France); Butashin, A.; Deryabin, A. [Russian Academy of Sciences, A.V. Shubnikov Institute of Crystallography (Russian Federation); Dill, F.-U.; Ehnes, A.; Herlitschke, M. [Deutsches Elektronen-Synchrotron DESY (Germany); Hermann, R. P.; Jafari, A. [JARA-FIT, Jülich Centre for Neutron Science JCNS and Peter Grünberg Institut PGI (Germany); Prokhorov, I. [Kaluga Branch of Shubnikov Institute of Crystallography RAS, Research Center for Space Materials Science (Russian Federation); Roshchin, B. [Russian Academy of Sciences, A.V. Shubnikov Institute of Crystallography (Russian Federation); Röhlsberger, R.; Schlage, K.; Sergueev, I.; Siemens, A.; Wille, H.-C., E-mail: hans.christian.wille@desy.de [Deutsches Elektronen-Synchrotron DESY (Germany)

2016-12-15

We report on a high resolution sapphire backscattering monochromator installed at the Dynamics beamline P01 of PETRA III. The device enables nuclear resonance scattering experiments on Mössbauer isotopes with transition energies between 20 and 60 keV with sub-meV to meV resolution. In a first performance test with {sup 119}Sn nuclear resonance at a X-ray energy of 23.88 keV an energy resolution of 1.34 meV was achieved. The device extends the field of nuclear resonance scattering at the PETRA III synchrotron light source to many further isotopes like {sup 151}Eu, {sup 149}Sm, {sup 161}Dy, {sup 125}Te and {sup 121}Sb.

X-ray optics developments at the APS for third-generation synchrotron radiation sources

International Nuclear Information System (INIS)

Mills, D.M.

1996-09-01

High brilliance third-generation synchrotron radiation sources simultaneously provide both a need and an opportunity for the development of new x-ray optical components. The high power and power densities of the x-ray beams produced by insertion devices have forced researchers to consider novel, and what may seem like exotic, approaches to the mitigation of thermal distortions that can dilute the beam brilliance delivered to the experiment or next optical component. Once the power has been filtered by such high heat load optical elements, specialized components can be employed that take advantage of the high degree of brilliance. This presentation reviews the performance of optical components that have been designed, fabricated, and tested at the Advanced Photon Source, starting with high heat load components and followed by examples of several specialized devices such as a milli-eV resolution (in-line) monochromator, a high energy x-ray phase retarder, and a phase zone plate with submicron focusing capability

Speckle-based at-wavelength metrology of x-ray optics at Diamond Light Source

Science.gov (United States)

Wang, Hongchang; Zhou, Tunhe; Kashyap, Yogesh; Sawhney, Kawal

2017-08-01

To achieve high resolution and sensitivity on the nanometer scale, further development of X-ray optics is required. Although ex-situ metrology provides valuable information about X-ray optics, the ultimate performance of X-ray optics is critically dependent on the exact nature of the working conditions. Therefore, it is equally important to perform in-situ metrology at the optics' operating wavelength (`at-wavelength' metrology) to optimize the performance of X-ray optics and correct and minimize the collective distortions of the upstream beamline optics, e.g. monochromator, windows, etc. Speckle-based technique has been implemented and further improved at Diamond Light Source. We have demonstrated that the angular sensitivity for measuring the slope error of an optical surface can reach an accuracy of two nanoradians. The recent development of the speckle-based at-wavelength metrology techniques will be presented. Representative examples of the applications of the speckle-based technique will also be given - including optimization of X-ray mirrors and characterization of compound refraction lenses. Such a high-precision metrology technique will be extremely beneficial for the manufacture and in-situ alignment/optimization of X-ray mirrors for next-generation synchrotron beamlines.

Toyota beamline (BL33XU) at SPring-8

Energy Technology Data Exchange (ETDEWEB)

Nonaka, T., E-mail: nonaka@mosk.tytlabs.co.jp; Dohmae, K.; Hayashi, Y.; Yamaguchi, S.; Nagai, Y.; Hirose, Y. [Toyota Central R& D Labs., Inc., 41-1 Nagakute Aichi 480-1192 Japan (Japan); Araki, T. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE UK (United Kingdom); Tanaka, T.; Kitamura, H. [RIKEN Harima Institute 1-1-1 Koto Sayo, Hyogo 679-5148 (Japan); Uruga, T.; Yamazaki, H.; Yumoto, H.; Ohashi, H.; Goto, S. [JASRI/SPring-8 1-1-1 Koto Sayo, Hyogo 679-5148 (Japan)

2016-07-27

The Toyota beamline (BL33XU) at SPring-8 is an undulator beamline developed to assist in the study of various automotive-related materials. The light source is a tapered in-vacuum undulator that provides a variable energy band width as well as a high brilliance X-ray beam. Two different optical arrangements are available: Optics 1 and Optics 2. Optics 1 is dedicated to time-resolved X-ray absorption spectroscopy (XAFS), and consists of two channel-cut crystal monochromators and four water-cooled flat Si mirrors. The Si(111) and Si(220) monochromator crystals cover an energy range of 4.0–46.0 keV and are driven by high-speed AC servo motors. These monochromators, in conjunction with the tapered undulator, enable high-quality XAFS data acquisition with a temporal resolution of 10 ms. Optics 2 is optimized for X-ray diffraction, scattering and imaging and includes a recently installed double crystal monochromator, two water-cooled flat Si mirrors and Kirkpatrick-Baez (KB) focusing mirrors. The monochromator incorporates parallel mounted Si(111) and Si(311) crystals and covers an energy range of 4.5–70 keV. The beamline provides two experimental stations: Exp. Hutch 2 and Exp. Hutch 3. The gas supply system and mass spectrometers installed in Exp. Hutch 2 allow in-operando measurements under various atmospheres. The scanning three-dimensional X-ray diffraction (scanning 3DXRD) microscopy instrumentation developed and installed in Exp. Hutch 3 enables non-destructive orientation and stress mapping of 1 mm-thick steel specimens using a high energy microbeam.

Toyota beamline (BL33XU) at SPring-8

International Nuclear Information System (INIS)

Nonaka, T.; Dohmae, K.; Hayashi, Y.; Yamaguchi, S.; Nagai, Y.; Hirose, Y.; Araki, T.; Tanaka, T.; Kitamura, H.; Uruga, T.; Yamazaki, H.; Yumoto, H.; Ohashi, H.; Goto, S.

2016-01-01

The Toyota beamline (BL33XU) at SPring-8 is an undulator beamline developed to assist in the study of various automotive-related materials. The light source is a tapered in-vacuum undulator that provides a variable energy band width as well as a high brilliance X-ray beam. Two different optical arrangements are available: Optics 1 and Optics 2. Optics 1 is dedicated to time-resolved X-ray absorption spectroscopy (XAFS), and consists of two channel-cut crystal monochromators and four water-cooled flat Si mirrors. The Si(111) and Si(220) monochromator crystals cover an energy range of 4.0–46.0 keV and are driven by high-speed AC servo motors. These monochromators, in conjunction with the tapered undulator, enable high-quality XAFS data acquisition with a temporal resolution of 10 ms. Optics 2 is optimized for X-ray diffraction, scattering and imaging and includes a recently installed double crystal monochromator, two water-cooled flat Si mirrors and Kirkpatrick-Baez (KB) focusing mirrors. The monochromator incorporates parallel mounted Si(111) and Si(311) crystals and covers an energy range of 4.5–70 keV. The beamline provides two experimental stations: Exp. Hutch 2 and Exp. Hutch 3. The gas supply system and mass spectrometers installed in Exp. Hutch 2 allow in-operando measurements under various atmospheres. The scanning three-dimensional X-ray diffraction (scanning 3DXRD) microscopy instrumentation developed and installed in Exp. Hutch 3 enables non-destructive orientation and stress mapping of 1 mm-thick steel specimens using a high energy microbeam.

The double rotor neutron monochromator facility at the ET-RR-1 reactor

International Nuclear Information System (INIS)

Adib, M.; Maayouf, R.M.A.; Abdel-Kawy, A.; Gwaily, S.E.; Hamouda, I.

1983-01-01

A double rotor neutron monochromator recently installed in front of one of the ET-RR-1 reactor horizontal channels is described. The system consists of two rotors, suspended in magnetic field, spinning at speeds up to 16000 rpm with a constant phase angle relative to each producing bursts of monochromatic neutrons at the sample. Each of the rotors, 32 cm in diameter and 27 Kg in weight, has two slits to produce two neutron bursts per revolution. The slits are with radius of curvature 65.65 cm and 7 x 10 sq.mm cross-sectional area. The jitters of the phase between the rotors were measured at different rotation rates and were found not to exceed +- 1.5 μsec. The transmission function of one rotor system was measured and found to be in agreement with that theoretically predicted. (Auth.)

Curved crystal x-ray optics for monochromatic imaging with a clinical source.

Science.gov (United States)

Bingölbali, Ayhan; MacDonald, C A

2009-04-01

Monochromatic x-ray imaging has been shown to increase contrast and reduce dose relative to conventional broadband imaging. However, clinical sources with very narrow energy bandwidth tend to have limited intensity and field of view. In this study, focused fan beam monochromatic radiation was obtained using doubly curved monochromator crystals. While these optics have been in use for microanalysis at synchrotron facilities for some time, this work is the first investigation of the potential application of curved crystal optics to clinical sources for medical imaging. The optics could be used with a variety of clinical sources for monochromatic slot scan imaging. The intensity was assessed and the resolution of the focused beam was measured using a knife-edge technique. A simulation model was developed and comparisons to the measured resolution were performed to verify the accuracy of the simulation to predict resolution for different conventional sources. A simple geometrical calculation was also developed. The measured, simulated, and calculated resolutions agreed well. Adequate resolution and intensity for mammography were predicted for appropriate source/optic combinations.

Study of optical emission spectroscopy with inductively coupled plasma torch

International Nuclear Information System (INIS)

Bauer, M.

1982-01-01

Inductively coupled plasma optical emission spectroscopy is an excellent tool for quantitative multielement trace analysis. This paper describes the performance of a computer-controlled sequential measurement system. Chemical and ionization interferences are shown to be negligible due to the characteristics of the inductively coupled plasma, spectral interferences are eliminated by using a high-resolution monochromator and computer data handling. Good accuracy is achieved for most of the interesting elements, as is shown from both an interlaboratory test and from comparison of the results of water samples from the rivers Elbe and Weser with those achieved with neutron activation and X-ray fluorescence analysis. (orig.) [de

A beam intensity monitor for the evaluation beamline for soft x-ray optical elements

International Nuclear Information System (INIS)

Imazono, Takashi; Moriya, Naoji; Harada, Yoshihisa; Sano, Kazuo; Koike, Masato

2012-01-01

Evaluation Beamline for Soft X-Ray Optical Elements (BL-11) at the SR Center of Ritsumeikan University has been operated to measure the wavelength and angular characteristics of soft x-ray optical components in a wavelength range of 0.65-25 nm using a reflecto-diffractometer (RD). The beam intensity monitor that has been equipped in BL-11 has observed the signal of the zero-th order light. For the purpose of more accurate evaluation of the performance of optical components, a new beam intensity monitor to measure the intensity of the first order light from the monochromator in BL-11 has been developed and installed in just front of RD. The strong positive correlation between the signal of the beam monitor and a detector equipped in the RD is shown. It is successful that the beam intensity of the first order light can be monitored in real time.

The at-wavelength metrology facility for UV- and XUV-reflection and diffraction optics at BESSY-II

Science.gov (United States)

Schäfers, F.; Bischoff, P.; Eggenstein, F.; Erko, A.; Gaupp, A.; Künstner, S.; Mast, M.; Schmidt, J.-S.; Senf, F.; Siewert, F.; Sokolov, A.; Zeschke, Th.

2016-01-01

A technology center for the production of high-precision reflection gratings has been established. Within this project a new optics beamline and a versatile reflectometer for at-wavelength characterization of UV- and XUV-reflection gratings and other (nano-) optical elements has been set up at BESSY-II. The Plane Grating Monochromator beamline operated in collimated light (c-PGM) is equipped with an SX700 monochromator, of which the blazed gratings (600 and 1200 lines mm−1) have been recently exchanged for new ones of improved performance produced in-house. Over the operating range from 10 to 2000 eV this beamline has very high spectral purity achieved by (i) a four-mirror arrangement of different coatings which can be inserted into the beam at different angles and (ii) by absorber filters for high-order suppression. Stray light and scattered radiation is removed efficiently by double sets of in situ exchangeable apertures and slits. By use of in- and off-plane bending-magnet radiation the beamline can be adjusted to either linear or elliptical polarization. One of the main features of a novel 11-axes reflectometer is the possibility to incorporate real life-sized gratings. The samples are adjustable within six degrees of freedom by a newly developed UHV-tripod system carrying a load up to 4 kg, and the reflectivity can be measured between 0 and 90° incidence angle for both s- and p-polarization geometry. This novel powerful metrology facility has gone into operation recently and is now open for external users. First results on optical performance and measurements on multilayer gratings will be presented here. PMID:26698047

High heat load x-ray optics research and development at the Advanced Photon Source -- An overview

International Nuclear Information System (INIS)

Lee, Wah-Keat; Mills, D.M.

1993-09-01

Insertion devices at third generation synchrotron radiation sources such as the APS are capable of producing x-ray beams with total power in excess of 7 kilowatts or power densities of 150 watts/mm 2 at a typical location of the optical components. Optical elements subjected to these types of heat fluxes will suffer considerably unless carefully designed to withstand these unprecedented power loadings. At the Advanced Photon Source (APS), we have an aggressive R ampersand D program aimed at investigating possible methods to mitigate thermal distortions. The approaches being studied include, improved heat exchangers, use of liquid gallium and liquid nitrogen as coolants, novel crystal geometries, power filtering, and replacement of silicon with diamond for crystal monochromators. This paper will provide an overview of the high heat load x-ray optics program at the APS

Liquid-metal-cooled, curved-crystal monochromator for Advanced Photon Source bending-magnet beamline 1-BM

International Nuclear Information System (INIS)

Brauer, S.; Rodricks, B.; Assoufid, L.; Beno, M.A.; Knapp, G.S.

1996-06-01

The authors describe a horizontally focusing curved-crystal monochromator that invokes a 4-point bending scheme and a liquid-metal cooling bath. The device has been designed for dispersive diffraction and spectroscopy in the 5--20 keV range, with a predicted focal spot size of ≤ 100 microm. To minimize thermal distortions and thermal equilibration time, the 355 x 32 x 0.8 mm crystal will be nearly half submerged in a bath of Ga-In-Sn-Zn alloy. The liquid metal thermally couples the crystal to the water-cooled Cu frame, while permitting the required crystal bending. Calculated thermal profiles and anticipated focusing properties are discussed

High heat load performance of an inclined crystal monochromator with liquid gallium cooling on the CHESS-ANL undulator

International Nuclear Information System (INIS)

Macrander, A.T.; Lee, W.K.; Smither, R.K.; Mills, D.M.

1992-01-01

Recent results for the performance of a novel double crystal monochromator subjected to high heat loads on an APS prototype undulator at the Cornell High Energy Synchrotron Source (CHESS) are presented. The monochromator was designed to achieve symmetric diffraction from asymmetric planes to spread out the beam footprint thereby lowering the incident power density. Both crystals had (111) oriented surfaces and were arranged such that the beam was diffracted from the (11 bar 1) planes at 5 KeV. Rocking curves with minimal distortion were obtained at a ring electron current of 100 mA. This corresponded to 380 Watts total power and an average power density of 40 Watts/mm 2 normal to the incident beam. These results are compared to data obtained from the same crystals in the standard geometry (diffracting planes parallel to surface). The footprint area in the inclined case was three times that of the standard case. We also obtained rocking curve data for the (333) reflection at 15 KeV for both standard and inclined cases, and these data also showed a minimal distortion only for the inclined case. In addition, thermal data were obtained via infrared pyrometry. Liquid gallium flow rates of up to 2 gallons per minute were investigated. The diffraction data revealed a dramatically improved performance for the inclined crystal case

3m vacuum ultraviolet spectrometer with optical multichanel detector

International Nuclear Information System (INIS)

Marin, P.; Peraza, C.; Blanco, F.; Campos, J.

1993-01-01

This paper, describes the design and the performance of a normal incidence vacuum ultraviolet spectrometer, for the 300-2400 A spectral range. It is provided with a multichannel detection system. The monochromator is original design and it has been built at CIEMAT: It is equipped with a 3 m concave holographic grating with 2400 grooves/mm. The multichannel detector consists of a windowless double microchannel plate/phosphor screen image intensifier, coupled by fiber optic to a 1024 elements self-scanning linear photodiode array. The output from the arrays is digitized by a 12-bit analog to digital converter and stored in a computer for its later analysis. The necessary software to store and display data has been developed. (Author)

Use of a GPGPU means for the development of search programs of defects of monochrome half-tone pictures

International Nuclear Information System (INIS)

Dudnik, V.A.; Kudryavtsev, V.I.; Sereda, T.M.; Us, S.A.; Shestakov, M.V.

2013-01-01

Application of a GPGPU means for the development of search programs of defects of monochrome half-tone pictures is described. The description of realization of algorithm of search of images' defects by the means of technology CUDA (Compute Unified Device Architecture - the unified hardware-software decision for parallel calculations on GPU) companies NVIDIA is resulted. It is done the comparison of the temporary characteristics of performance of images' updating without application GPU and with use of opportunities of graphic processor GeForce 8800.

Time and spectrum-resolving multiphoton correlator for 300–900 nm

Energy Technology Data Exchange (ETDEWEB)

Johnsen, Kelsey D.; Thibault, Marilyne; Jennewein, Thomas [Institute for Quantum Computing and Department for Physics and Astronomy, University of Waterloo, 200 University Ave. West, Waterloo, Ontario N2L 3G1 (Canada); Kolenderski, Piotr, E-mail: kolenderski@fizyka.umk.pl [Institute for Quantum Computing and Department for Physics and Astronomy, University of Waterloo, 200 University Ave. West, Waterloo, Ontario N2L 3G1 (Canada); Faculty of Physics, Astronomy and Informatics, Institute of Physics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun (Poland); Scarcella, Carmelo; Tosi, Alberto [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy)

2014-10-14

We demonstrate a single-photon sensitive spectrometer in the visible range, which allows us to perform time-resolved and multi-photon spectral correlation measurements at room temperature. It is based on a monochromator composed of two gratings, collimation optics, and an array of single photon avalanche diodes. The time resolution can reach 110 ps and the spectral resolution is 2 nm/pixel, limited by the design of the monochromator. This technique can easily be combined with commercial monochromators and can be useful for joint spectrum measurements of two photons emitted in the process of parametric down conversion, as well as time-resolved spectrum measurements in optical coherence tomography or medical physics applications.

Minimization of spurious strains by using a Si bent-perfect-crystal monochromator: neutron surface strain scanning of a shot-peened sample

Science.gov (United States)

Rebelo Kornmeier, Joana; Gibmeier, Jens; Hofmann, Michael

2011-06-01

Neutron strain measurements are critical at the surface. When scanning close to a sample surface, aberration peak shifts arise due to geometrical and divergence effects. These aberration peak shifts can be of the same order as the peak shifts related to residual strains. In this study it will be demonstrated that by optimizing the horizontal bending radius of a Si (4 0 0) monochromator, the aberration peak shifts from surface effects can be strongly reduced. A stress-free sample of fine-grained construction steel, S690QL, was used to find the optimal instrumental conditions to minimize aberration peak shifts. The optimized Si (4 0 0) monochromator and instrument settings were then applied to measure the residual stress depth gradient of a shot-peened SAE 4140 steel sample to validate the effectiveness of the approach. The residual stress depth profile is in good agreement with results obtained by x-ray diffraction measurements from an international round robin test (BRITE-EURAM-project ENSPED). The results open very promising possibilities to bridge the gap between x-ray diffraction and conventional neutron diffraction for non-destructive residual stress analysis close to surfaces.

Minimization of spurious strains by using a Si bent-perfect-crystal monochromator: neutron surface strain scanning of a shot-peened sample

International Nuclear Information System (INIS)

Rebelo Kornmeier, Joana; Hofmann, Michael; Gibmeier, Jens

2011-01-01

Neutron strain measurements are critical at the surface. When scanning close to a sample surface, aberration peak shifts arise due to geometrical and divergence effects. These aberration peak shifts can be of the same order as the peak shifts related to residual strains. In this study it will be demonstrated that by optimizing the horizontal bending radius of a Si (4 0 0) monochromator, the aberration peak shifts from surface effects can be strongly reduced. A stress-free sample of fine-grained construction steel, S690QL, was used to find the optimal instrumental conditions to minimize aberration peak shifts. The optimized Si (4 0 0) monochromator and instrument settings were then applied to measure the residual stress depth gradient of a shot-peened SAE 4140 steel sample to validate the effectiveness of the approach. The residual stress depth profile is in good agreement with results obtained by x-ray diffraction measurements from an international round robin test (BRITE-EURAM-project ENSPED). The results open very promising possibilities to bridge the gap between x-ray diffraction and conventional neutron diffraction for non-destructive residual stress analysis close to surfaces

A high-energy double-crystal fixed exit monochromator for the X17 superconducting wiggler beam line at the NSLS

International Nuclear Information System (INIS)

Garrett, R.F.; Dilmanian, F.A.; Oversluizen, T.; Lenhard, A.; Berman, L.E.; Chapman, L.D.; Stoeber, W.

1992-01-01

A high-energy double-crystal x-ray monochromator has been constructed for use on the X-17 beam line at the National Synchrotron Light Source (NSLS). Its design is based on the ''boomerang'' right angle linkage, and features a fixed exit beam, a cooled first crystal, and an energy range of 8--92 keV. The entire mechanism is UHV compatible. The design is described and performance details, obtained in testing at the X17 beam line, are presented

Multiple order reflections in crystal neutron monochromators

International Nuclear Information System (INIS)

Fulfaro, R.

1976-01-01

A study of the higher order reflections in neutron crystal monochromators was made in order to obtain, for the IEA single crystal spectrometer, the operation range of 1,0eV to 0,01eV. Two crystals were studied, an Al(III) near 1,0eV and a Ge(III) in lower energies. For the Ge(III) case the higher order contaminations in the reflected beam were determined using as standard the gold total neutron cross section and performing the crystal reflectivity calculation for several orders of reflection. The knowledge of the contamination for each order as a function of neutron wavelength allows the optimization of the filter thickness in order to avoid higher order neutrons. The Ge(III) crystal was used because its second order reflections are theoretically forbidden, giving an advantage on other crystals, since measurements can be made until 0.02eV directly without filters. In the energy range 0.02 to 0.01eV, order contaminations higher than the second are present, therefore, either quartz filters are employed or calculated corrections are applied to the experimental data. The Al(III) crystal was used in order to estimate the second order contamination effect, in the iridium resonance measurements, at E 0 = 0.654eV. In that region, approximations can be made and it was not necessary to make the crystal reflectivity calculation for the filters thickness optimization. Since only the second order affects the results in that region, tellurium was used for the filtration, because this element has a resonance in the range of neutrons with energy 4E [pt

The role of surface topography in predicting scattering at grazing incidence from optical surfaces

International Nuclear Information System (INIS)

Rehn, V.; Jones, V.O.; Elson, J.M.; Bennett, J.M.

1980-01-01

Monochromator design and the design of optical experiments at XUV and X-ray wavelengths are frequently limited by scattering from optical components, yet theoretical treatments are few and untested experimentally. This is partly due to the failure of scattering models used in the visible and near UV when the wavelength becomes comparable to, or smaller than, the topographic features on the surface, and partly it is due to the difficulty in measuring the topography on the required size scale. We briefly review the theoretical problems and prospects for accurately predicting both the magnitude and angular distribution of scattering at grazing incidence from optical surfaces. Experimental methods for determining and representing the surface topography are also reviewed, together with their limitations and ranges of applicability. Finally, the first results of our experiments, conducted recently at the Stanford Synchrotron Radiation Laboratory on the angular distribution of scattering by surfaces of known topography are presented and discussed, along with their potential implications for the theory of scattering, and for XUV and X-ray optical components. (orig.)

Perfect-crystal x-ray optics to treat x-ray coherence

International Nuclear Information System (INIS)

Yamazaki, Hiroshi; Ishikawa, Tetsuya

2007-01-01

X-ray diffraction of perfect crystals, which serve as x-ray monochromator and collimator, modifies coherence properties of x-ray beams. From the time-dependent Takagi-Taupin equations that x-ray wavefields obey in crystals, the reflected wavefield is formulated as an integral transform of a general incident wavefield with temporal and spatial inhomogeneity. A reformulation of rocking-curve profiles from the field solution of the Takagi-Taupin equations allows experimental evaluation of the mutual coherence function of x-ray beam. The rigorous relationship of the coherence functions between before and after reflection clarifies how the coherence is transferred by a crystal. These results will be beneficial to developers of beamline optics for the next generation synchrotron sources. (author)

Phase shifting white light interferometry using colour CCD for optical metrology and bio-imaging applications

Science.gov (United States)

Upputuri, Paul Kumar; Pramanik, Manojit

2018-02-01

Phase shifting white light interferometry (PSWLI) has been widely used for optical metrology applications because of their precision, reliability, and versatility. White light interferometry using monochrome CCD makes the measurement process slow for metrology applications. WLI integrated with Red-Green-Blue (RGB) CCD camera is finding imaging applications in the fields optical metrology and bio-imaging. Wavelength dependent refractive index profiles of biological samples were computed from colour white light interferograms. In recent years, whole-filed refractive index profiles of red blood cells (RBCs), onion skin, fish cornea, etc. were measured from RGB interferograms. In this paper, we discuss the bio-imaging applications of colour CCD based white light interferometry. The approach makes the measurement faster, easier, cost-effective, and even dynamic by using single fringe analysis methods, for industrial applications.

Multilayer optics for x-ray analysis: design - fabrication - application

International Nuclear Information System (INIS)

Dietsch, R.; Holz, Th.; Bruegemann, L.

2002-01-01

Full text: The use of multilayer optics induced a decisive extension of opportunities in laboratory based X-ray analysis. With the growing number of different applications, more and more dedicated X-ray optics are required, optimized for the spectral range they are intended to be used for. Both the characteristic of the used X-ray source and the design of the multilayer optics finally define the performance of the conditioned incident beam for the application. In any case, qualified spacer and absorber materials have to be selected for the deposition of the multilayer in respect to the designated X-ray wavelength. X-ray optical devices based on uniform multilayers have the advantage of a wide acceptance angle but show chromatic aberrations. This effect can be avoided by synthesizing a multilayer with a lateral thickness gradient. The gradient ensures that any beam of a certain wavelength emitted from an infinite narrow X-ray source impinging the multilayer optics fulfills the Bragg condition. Three different types of curvature of laterally graded multilayer mirrors are used for X-ray analysis experiments: parabolic, elliptic and planar, which result in parallel, focusing and divergent beam conditions, respectively. Furthermore, the X-ray beam characteristics: intensity, monochromasy, divergence, beam width and brilliance can be additionally conditioned by combining one multilayer optics with either a different optic and/or with a crystal monochromator. The deposition of nanometer-multilayers, used as X-ray optical components, result in extraordinary requirements of the deposition process concerning precision, reproducibility and long term stability. Across a stack of more than 150 individual layers with thicknesses in the range between 1 to 10 nm, a variation of single layer thickness considerably lower than σ D = 0.1 nm and an interface roughness below σ R = 0.25 nm have to be achieved. Thickness homogeneity Δd/d -8 have to be guaranteed across macroscopic

3m Vacuum Ultraviolet Spectrometer with Optical Multichannel Detector

International Nuclear Information System (INIS)

Martin, P.; Peraza, C.; Blanco, F.; Campos, J.

1993-01-01

This paper describes the design and the performance of a normal incidence vacuum ultraviolet spectrometer, for the 300-2400 A spectral range. It is provided with a multichannel detection system. The monochromator is original design and it has been built at CIEMAT. It is equipped with a 3 m concave holographic grating with 2400 grooves/mm. The multichannel detector consists of a windowless double microchannel plate / phosphor screen image intensifier, coupled by fiber optic to a 1024 elements self-scanning linear photodiode array. The output from the array is digitized by a 12-bit analog to digital converter and stored in a computer, for its later analysis. The necessary software to store and display data has been developed. (Author) 18 refs

Double tungsten coil atomic absorption spectrometer based on an acousto-optic tunable filter

International Nuclear Information System (INIS)

Jora, M.Z.; Nóbrega, J.A.; Rohwedder, J.J.R.; Pasquini, C.

2015-01-01

An atomic absorption spectrometer based on a quartz acousto-optic tunable filter (AOTF) monochromator operating in the 271–453 nm range, is described. The instrument was tailored to study the formation and evolution of electrothermal atomic cloud induced either by one or two tungsten coils. The spectrometer also includes a fast response programmable photomultiplier module for data acquisition, and a power supply capable of driving two parallel tungsten coils independently. The atomization cell herein described was manufactured in PTFE and presents a new design with reduced size. Synchronization between the instant of power delivering to start the atomization process and the detection was achieved, allowing for monitoring the atomization and thermal events synchronously and in real time. Absorption signals can be sampled at a rate of a few milliseconds, compatible with the fast phenomena that occur with electrothermal metallic atomizers. The instrument performance was preliminarily evaluated by monitoring the absorption of radiation of atomic clouds produced by standard solutions containing chromium or lead. Its quantitative performance was evaluated by using Cr aqueous solutions, resulting in detection limits as low as 0.24 μg L −1 , and a relative standard deviation of 3%. - Highlights: • The use of an Acousto-Optic Tunable Filter (AOTF) as monochromator element in WC AAS is presented for the first time. • The system includes the possibility of using one or two parallel coils. • We propose a new atomization cell design, manufactured on PTFE with reduced size. • The temperature of the coils and the atomic clouds of Pb and Cr were observed synchronously with high temporal resolution

X-ray pencil beam facility for optics characterization

Science.gov (United States)

Krumrey, Michael; Cibik, Levent; Müller, Peter; Bavdaz, Marcos; Wille, Eric; Ackermann, Marcelo; Collon, Maximilien J.

2010-07-01

The Physikalisch-Technische Bundesanstalt (PTB) has used synchrotron radiation for the characterization of optics and detectors for astrophysical X-ray telescopes for more than 20 years. At a dedicated beamline at BESSY II, a monochromatic pencil beam is used by ESA and cosine Research since the end of 2005 for the characterization of novel silicon pore optics, currently under development for the International X-ray Observatory (IXO). At this beamline, a photon energy of 2.8 keV is selected by a Si channel-cut monochromator. Two apertures at distances of 12.2 m and 30.5 m from the dipole source form a pencil beam with a typical diameter of 100 μm and a divergence below 1". The optics to be investigated is placed in a vacuum chamber on a hexapod, the angular positioning is controlled by means of autocollimators to below 1". The reflected beam is registered at 5 m distance from the optics with a CCD-based camera system. This contribution presents design and performance of the upgrade of this beamline to cope with the updated design for IXO. The distance between optics and detector can now be 20 m. For double reflection from an X-ray Optical Unit (XOU) and incidence angles up to 1.4°, this corresponds to a vertical translation of the camera by 2 m. To achieve high reflectance at this angle even with uncoated silicon, a lower photon energy of 1 keV is available from a pair of W/B4C multilayers. For coated optics, a high energy option can provide a pencil beam of 7.6 keV radiation.

Optics of a double focussing magnetic sector by fringe effect (1960); Optique d'un secteur magnetique a double focalisation par effet de franges (1960)

Energy Technology Data Exchange (ETDEWEB)

Krafft, J [Commissariat a l' Energie Atomique, Lab. de Physique Nucleaire, Grenoble (France). Centre d' Etudes Nucleaires; [Grenoble-1 Univ., 38 (France); [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1960-07-01

General study of the optical elements of a double focussing magnetic selector by fringe effect, with a view to its application to the monochromatization of the proton, deuteron or triton beam of the 1.4 MeV accelerator. (author) [French] Etude generale des elements optiques d'un selecteur magnetique a double focalisation par effet de franges, en vue de l'application a la monochromation du faisceau de protons, deutons ou tritons de l'accelerateur 1,4 MeV. (auteur)

3m Vacuum Ultraviolet Spectrometer with Optical Multichannel Detector; Espectrometro de ultravioleta de vacio de 3m provisto de sistema de deteccion optical multicanal

Energy Technology Data Exchange (ETDEWEB)

Martin, P; Peraza, C; Blanco, F; Campos, J

1993-07-01

This paper describes the design and the performance of a normal incidence vacuum ultraviolet spectrometer, for the 300-2400 A spectral range. It is provided with a multichannel detection system. The monochromator is original design and it has been built at CIEMAT. It is equipped with a 3 m concave holographic grating with 2400 grooves/mm. The multichannel detector consists of a windowless double microchannel plate / phosphor screen image intensifier, coupled by fiber optic to a 1024 elements self-scanning linear photodiode array. The output from the array is digitized by a 12-bit analog to digital converter and stored in a computer, for its later analysis. The necessary software to store and display data has been developed. (Author) 18 refs.

Optical sensor for measuring American Lobster vitality

International Nuclear Information System (INIS)

Tomassetti, Brian R. A.; Vetelino, John F.

2011-01-01

The vitality of the American Lobster (Homarus americanus) is correlated to the total hemolymph protein (THP) in lobster hemolymph (blood). The standard technique for determining lobster vitality is to draw blood from a lobster and measure THP with a refractometer. This technique is invasive and endangers the lobster's health since blood must be drawn from the lobster. In the present work an optical sensor is developed to measure a lobster's vitality in vivo. It is comprised of a broadband light source, a monochromator, a fiber optic reflection probe, a spectrometer and a computer. This sensor measures protein concentrations by exciting a lobster with 280 nm and 334 nm wavelength light sources and measuring the corresponding absorbance peaks for THP and the fluorescence peak for hemocyanin (Hc), the majority protein in hemolymph. In this work several lobsters are tested. For each lobster, absorbance and fluorescence peaks are measured using the sensor and compared to protein concentrations measured using a refractometer. It is found that the shell thickness and muscle density, which correspond directly to protein concentration and the molting stage of the lobster have a significant effect on the absorbance and fluorescence measurements. It is also found that within specific molting stages, such as pre-molt and post-molt, protein concentration measured with a refractometer correlates linearly to absorbance and fluorescence measurements with the optical sensor.

Optical Sensor for Measuring American Lobster Vitality

Science.gov (United States)

Tomassetti, Brian R. A.; Vetelino, John F.

2011-06-01

The vitality of the American Lobster (Homarus americanus) is correlated to the total hemolymph protein (THP) in lobster hemolymph (blood). The standard technique for determining lobster vitality is to draw blood from a lobster and measure THP with a refractometer. This technique is invasive and endangers the lobster's health since blood must be drawn from the lobster. In the present work an optical sensor is developed to measure a lobster's vitality in vivo. It is comprised of a broadband light source, a monochromator, a fiber optic reflection probe, a spectrometer and a computer. This sensor measures protein concentrations by exciting a lobster with 280 nm and 334 nm wavelength light sources and measuring the corresponding absorbance peaks for THP and the fluorescence peak for hemocyanin (Hc), the majority protein in hemolymph. In this work several lobsters are tested. For each lobster, absorbance and fluorescence peaks are measured using the sensor and compared to protein concentrations measured using a refractometer. It is found that the shell thickness and muscle density, which correspond directly to protein concentration and the molting stage of the lobster have a significant effect on the absorbance and fluorescence measurements. It is also found that within specific molting stages, such as pre-molt and post-molt, protein concentration measured with a refractometer correlates linearly to absorbance and fluorescence measurements with the optical sensor.

An undulator based high flux and high resolution beamline for atomic, molecular and optical science (AMOS) research at INDUS-2 synchrotron radiation source (SRS)

International Nuclear Information System (INIS)

Das, Asim Kumar; Rajasekhar, B.N.; Sahoo, N.K.

2014-08-01

A dedicated UV-VUV and soft X-ray beamline to provide several new research opportunities in Photon induced processes in the energy range of 6-250 eV for Atomic Molecular and Optical Science (AMOS) research, a domain still less explored both at national as well international level, has been proposed by Atomic and Molecular Physics Division, BARC. This beamline will use a planar permanent magnet (PPM) undulator based on Indus-2 Synchrotron Radiation Source (SRS), a 2.5 GeV third generation electron storage ring at RRCAT, Indore, India and is expected to offer a variety of opportunities for more advanced and sustained investigations for AMOS research. A plane mirror and a toroidal mirror are used as the pre-focusing optics of the AMOS beamline. A varied line spacing plane grating monochromator (VLSPGM) in a converging beam, constant included angle mode containing one toroidal focusing mirror and four interchangeable gratings is to be used to cover the energy range of 6 to 250 eV and obtain resolving powers ∼10 4 and intensity ∼10 12 ph/s at the sample position. A toroidal mirror is used to focus the diverging monochromatic light from the monochromator at a distance of 150 cm with a 1:1 magnification. As the first step towards the beamline optics design, the evaluation of the PPM undulator radiation characteristics relevant to beamline design has been performed using the Indus-2 SRS parameters in the long straight section of the ring, PPM undulator parameters, and the empirical expressions available in literature. The software resources such as XOPS, ESRF, France and SPECTRA, Photon factory, Japan have been used for detailed modelling and verification of the empirical computations. Beamline layout preparation, optimization, imaging performance evaluation, and resolving power calculations for ideal beamline optics are carried out using SHADOWVUI, an extension of XOPS software resource. A new mounting of the optical components in the monochromator has been proposed

VUV-soft x-ray beamline for spectroscopy and calibration

International Nuclear Information System (INIS)

Bartlett, R.J.; Trela, W.J.; Michaud, F.D.; Southworth, S.H.; Rothe, R.; Alkire, R.W.

1986-01-01

The authors describe the design and performance of the Los Alamos VUV synchrotron radiation beamline, U3C, on the VUV ring of the National Synchrotron Light Source at Brookhaven National Laboratory. The beamline uses separate function optics to collect and focus the horizontally and vertically diverging beam. The monochromator is a grazing incidence Roland circle instrument of the extended grasshopper design (ERG). A post monochromator refocusing mirror is used to focus or collimate the diverging beam from the monochromator. The beamline control and diagnostics systems are also discussed

X-Ray Absorption Near-Edge Structure (XANES) of Calcium L3,2 Edges of Various Calcium Compounds and X-Ray Excited Optical Luminescence (XEOL) Studies of Luminescent Calcium Compounds

International Nuclear Information System (INIS)

Ko, J. Y. Peter; Zhou Xingtai; Sham, T.-K.; Heigl, Franziskus; Regier, Tom; Blyth, Robert

2007-01-01

X-ray absorption at calcium L3,2 edges of various calcium compounds were measured using a high resolution Spherical Grating Monochromator (SGM) at the Canadian Light Source (CLS). We observe that each compound has its unique fine structure of L3,2 edges. This uniqueness is due to differences in local structure of compounds. We also performed (X-ray Excited Optical Luminescence) XEOL of selected luminescent calcium compounds to investigate their optical properties. XEOL is a photon-in-photon-out technique in which the optical luminescence that is excited by tunable x-rays from a synchrotron light source is monitored. Depending on excitation energy of the x-ray, relative intensities of luminescence peaks vary. Recent findings of the results will be presented here

X-ray Optics for BES Light Source Facilities

Energy Technology Data Exchange (ETDEWEB)

Mills, Dennis [Argonne National Lab. (ANL), Argonne, IL (United States); Padmore, Howard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lessner, Eliane [Dept. of Energy (DOE), Washington DC (United States). Office of Science

2013-03-27

Each new generation of synchrotron radiation sources has delivered an increase in average brightness 2 to 3 orders of magnitude over the previous generation. The next evolution toward diffraction-limited storage rings will deliver another 3 orders of magnitude increase. For ultrafast experiments, free electron lasers (FELs) deliver 10 orders of magnitude higher peak brightness than storage rings. Our ability to utilize these ultrabright sources, however, is limited by our ability to focus, monochromate, and manipulate these beams with X-ray optics. X-ray optics technology unfortunately lags behind source technology and limits our ability to maximally utilize even today’s X-ray sources. With ever more powerful X-ray sources on the horizon, a new generation of X-ray optics must be developed that will allow us to fully utilize these beams of unprecedented brightness. The increasing brightness of X-ray sources will enable a new generation of measurements that could have revolutionary impact across a broad area of science, if optical systems necessary for transporting and analyzing X-rays can be perfected. The high coherent flux will facilitate new science utilizing techniques in imaging, dynamics, and ultrahigh-resolution spectroscopy. For example, zone-plate-based hard X-ray microscopes are presently used to look deeply into materials, but today’s resolution and contrast are restricted by limitations of the current lithography used to manufacture nanodiffractive optics. The large penetration length, combined in principle with very high spatial resolution, is an ideal probe of hierarchically ordered mesoscale materials, if zone-plate focusing systems can be improved. Resonant inelastic X-ray scattering (RIXS) probes a wide range of excitations in materials, from charge-transfer processes to the very soft excitations that cause the collective phenomena in correlated electronic systems. However, although RIXS can probe high-energy excitations, the most exciting and

X-ray Optics for BES Light Source Facilities

International Nuclear Information System (INIS)

Mills, Dennis; Padmore, Howard; Lessner, Eliane

2013-01-01

Each new generation of synchrotron radiation sources has delivered an increase in average brightness 2 to 3 orders of magnitude over the previous generation. The next evolution toward diffraction-limited storage rings will deliver another 3 orders of magnitude increase. For ultrafast experiments, free electron lasers (FELs) deliver 10 orders of magnitude higher peak brightness than storage rings. Our ability to utilize these ultrabright sources, however, is limited by our ability to focus, monochromate, and manipulate these beams with X-ray optics. X-ray optics technology unfortunately lags behind source technology and limits our ability to maximally utilize even today's X-ray sources. With ever more powerful X-ray sources on the horizon, a new generation of X-ray optics must be developed that will allow us to fully utilize these beams of unprecedented brightness. The increasing brightness of X-ray sources will enable a new generation of measurements that could have revolutionary impact across a broad area of science, if optical systems necessary for transporting and analyzing X-rays can be perfected. The high coherent flux will facilitate new science utilizing techniques in imaging, dynamics, and ultrahigh-resolution spectroscopy. For example, zone-plate-based hard X-ray microscopes are presently used to look deeply into materials, but today's resolution and contrast are restricted by limitations of the current lithography used to manufacture nanodiffractive optics. The large penetration length, combined in principle with very high spatial resolution, is an ideal probe of hierarchically ordered mesoscale materials, if zone-plate focusing systems can be improved. Resonant inelastic X-ray scattering (RIXS) probes a wide range of excitations in materials, from charge-transfer processes to the very soft excitations that cause the collective phenomena in correlated electronic systems. However, although RIXS can probe high-energy excitations, the most exciting

Beryllium, zinc and lead single crystals as a thermal neutron monochromators

Science.gov (United States)

Adib, M.; Habib, N.; Bashter, I. I.; Morcos, H. N.; El-Mesiry, M. S.; Mansy, M. S.

2015-03-01

The monochromatic features of Be, Zn and Pb single crystals are discussed in terms of orientation, mosaic spread, and thickness within the wavelength band from 0.04 up to 0.5 nm. A computer program MONO written in "FORTRAN-77", has been adapted to carry out the required calculations. Calculations show that a 5 mm thick of beryllium (HCP structure) single crystal cut along its (0 0 2) plane having 0.6° FWHM are the optimum parameters when it is used as a monochromator with high reflected neutron intensity from a thermal neutron flux. Furthermore, at wavelengths shorter than 0.16 nm it is free from the accompanying higher order ones. Zinc (HCP structure) has the same parameters, with intensity much less than the latter. The same features are seen with lead (FCC structure) cut along its (3 1 1) plane with less reflectivity than the former. However, Pb (3 1 1) is more preferable than others at neutron wavelengths ⩽ 0.1 nm, since the glancing angle (θ ∼ 20°) is more suitable to carry out diffraction experiments. For a cold neutron flux, the first-order neutrons reflected from beryllium is free from the higher orders up to 0.36 nm. While for Zn single crystal is up to 0.5 nm.

A laboratory-based hard x-ray monochromator for high-resolution x-ray emission spectroscopy and x-ray absorption near edge structure measurements

Energy Technology Data Exchange (ETDEWEB)

Seidler, G. T., E-mail: seidler@uw.edu; Mortensen, D. R.; Remesnik, A. J.; Pacold, J. I.; Ball, N. A.; Barry, N.; Styczinski, M.; Hoidn, O. R. [Physics Department, University of Washington, Seattle, Washington 98195-1560 (United States)

2014-11-15

We report the development of a laboratory-based Rowland-circle monochromator that incorporates a low power x-ray (bremsstrahlung) tube source, a spherically bent crystal analyzer, and an energy-resolving solid-state detector. This relatively inexpensive, introductory level instrument achieves 1-eV energy resolution for photon energies of ∼5 keV to ∼10 keV while also demonstrating a net efficiency previously seen only in laboratory monochromators having much coarser energy resolution. Despite the use of only a compact, air-cooled 10 W x-ray tube, we find count rates for nonresonant x-ray emission spectroscopy comparable to those achieved at monochromatized spectroscopy beamlines at synchrotron light sources. For x-ray absorption near edge structure, the monochromatized flux is small (due to the use of a low-powered x-ray generator) but still useful for routine transmission-mode studies of concentrated samples. These results indicate that upgrading to a standard commercial high-power line-focused x-ray tube or rotating anode x-ray generator would result in monochromatized fluxes of order 10{sup 6}–10{sup 7} photons/s with no loss in energy resolution. This work establishes core technical capabilities for a rejuvenation of laboratory-based hard x-ray spectroscopies that could have special relevance for contemporary research on catalytic or electrical energy storage systems using transition-metal, lanthanide, or noble-metal active species.

An x-ray beamline for the LNLS

International Nuclear Information System (INIS)

Cusatis, C.; Giles, C.

1990-01-01

In this paper an x-ray optics and high energy-resolution beamline for the XUV ring at LNLS is described. It consists of a monochromator serving a station for x-ray optics and another for high energy-resolution experiments. The constant offset, vacuum compatible double crystal monochromator is to be mounted in a bending magnet or wiggler port and will be located as near as possible of the ring. One rotation movement of both mechanically linked crystals and one short elastic translation of each crystal covers the energy range of 1 to 10 KeV. For θ B ∼ 90 on the first monochromator crystal the monochromatized beam is sent back through the electron ring and is received on the opposite side of the line at the high energy-resolution station. The main instrument at the x-ray optics station will be a triple axis diffractometer. This station, located as far as possible of the ring and, possibly, outside of main hall, will be used for x-ray interferometry, perfect crystal diffractometry, etc

Transmission test of the polyethylene shield against 40 and 65 MeV quasi monochrome neutron

International Nuclear Information System (INIS)

Nakao, Makoto; Nakamura, Takashi; Sakuya, Yoshimasa; Nauchi, Yasushi; Nakao, Noriaki; Tanaka, Susumu; Sakamoto, Yukio; Nakajima, Hiroshi; Nakane, Yoshihiro.

1996-01-01

Using 40 and 65 MeV quasi monochrome neutron of the AVF cyclotron installed at Takasaki Laboratory, Japan Atomic Energy Research Institute, the neutron energy spectra were measured after transmitting the polyethylene shield. Results of the shielding experiments using concrete and iron recognized as main shielding material were proposed previously. As data obtained in the experiments were useful for a bench-mark experiment to investigate for shielding calculation and sectional data set, a shielding calculation simulated with new experiment to compare with and investigate for the previous experimental data. As a result, it was found that calculation result of neutron flux transmitting through the polyethylene shield showed difference with increase of the shield thickness. And, reducing distance of the peak neutron was also found to be over-estimated in its calculation value, such as three and five times on 43 MeV at 120 and 180 cm thick, respectively. (G.K.)

Geometrical charged-particle optics. 2. ed.

International Nuclear Information System (INIS)

Rose, Harald

2013-01-01

Provides a unique theoretical treatment of charged-particle optics. Displays novel unpublished results on several topics. Provides insight into the properties of charged-particle devices. Treats wave optical properties of the electron. Presents the resolution limit of electron microscopes and novel theoretical treatment of the Stern-Gerlach effect. This second edition is an extended version of the first edition of Geometrical Charged-Particle Optics. The updated reference monograph is intended as a guide for researchers and graduate students who are seeking a comprehensive treatment of the design of instruments and beam-guiding systems of charged particles and their propagation in electromagnetic fields. Wave aspects are included in this edition for explaining electron holography, the Aharanov-Bohm effect and the resolution of electron microscopes limited by diffraction. Several methods for calculating the electromagnetic field are presented and procedures are outlined for calculating the properties of systems with arbitrarily curved axis. Detailed methods are presented for designing and optimizing special components such as aberration correctors, spectrometers, energy filters monochromators, ion traps, electron mirrors and cathode lenses. In particular, the optics of rotationally symmetric lenses, quadrupoles, and systems composed of these elements are discussed extensively. Beam properties such as emittance, brightness, transmissivity and the formation of caustics are outlined. Relativistic motion and spin precession of the electron are treated in a covariant way by introducing the Lorentz-invariant universal time and by extending Hamilton's principle from three to four spatial dimensions where the laboratory time is considered as the fourth pseudo-spatial coordinate. Using this procedure and introducing the self action of the electron, its accompanying electromagnetic field and its radiation field are calculated for arbitrary motion. In addition, the Stern

An energy-dispersive X-ray monochromator for measurements in the soft X-ray spectra: design, construction and first measurements. Ein energiedispersiver Roentgenmonochromator mit der Moeglichkeit von Messungen im weichen Roentgenbereich: Entwurf, Aufbau und erste Messungen

Energy Technology Data Exchange (ETDEWEB)

Steil, S.

1993-12-01

An Energy-Dispersive X-ray Monochromator (EDM) for time-resolved X-ray absorption spectroscopy was built in the Synchrotron radiation laboratory at the 3.5 GeV ELectron Stretcher and Accelerator (ELSA). Bragg angles up to 70 and a specially designed vacuum system allow measurements down to an energy of 2.149 keV (P K-edge) with a Si(111)-crystal. Compared to a standard double crystal monochromator and for an EXAFS spectrum at the Cu K-edge at 8.979 keV for concentrated samples, the EDM boosts time resolution by 3 orders of magnitude. The time resolution increases by a factor of 50 for a XANES spectrum at the S K-edge at 2.472 keV for a rubber sample with 4% sulfur. The energy resolution of the EDM is limited by the Darwin width [Omega] of the Bragg crystal. The harmonics in the 'monochromatized' beam, which increase to lower energies, could be nearly eliminated by using a quartz mirror. The spherical aberration of the focus was described theoretically for a cylindrically bent crystal and compared with measurements. In a first time-resolved measurement at the S K-edge, which comprehended about 120 spectra taken in 40 minutes, the thermal ageing of a rubber sample was investigated to demonstrate the performance of the monochromator. (orig.)

Performance of an optimally contact-cooled high-heat-load mirror at the APS

International Nuclear Information System (INIS)

Cai, Z.; Khounsary, A.; Lai, B.; McNulty, I.; Yun, W.

1998-01-01

X-ray undulator beamlines at third-generation synchrotrons facilities use either a monochromator or a mirror as the first optical element. In this paper, the thermal and optical performance of an optimally designed contact-cooled high-heat-load x-ray mirror used as the first optical element on the 2ID undulator beamline at the Advanced Photon Source (APS) is reported. It is shown that this simple and economical mirror design can comfortably handle the high heat load of undulator beamlines and provide good performance with long-term reliability and ease of operation. Availability and advantages of such mirrors can make the mirror-first approach to high-heat-load beamline design an attractive alternative to monochromator-first beamlines in many circumstances

A beamline for macromolecular crystallography at the Advanced Light Source

International Nuclear Information System (INIS)

Padmore, H.A.; Earnest, T.; Kim, S.H.; Thompson, A.C.; Robinson, A.L.

1994-08-01

A beamline for macromolecular crystallography has been designed for the ALS. The source will be a 37-pole wiggler with a, 2-T on-axis peak field. The wiggler will illuminate three beamlines, each accepting 3 mrad of horizontal aperture. The central beamline will primarily be used for multiple-wavelength anomalous dispersion measurements in the wavelength range from 4 to 0.9 angstrom. The beamline optics will comprise a double-crystal monochromator with a collimating pre-mirror and a double-focusing mirror after the monochromator. The two side stations will be used for fixed-wavelength experiments within the wavelength range from 1.5 to 0.95 angstrom. The optics will consist of a conventional vertically focusing cylindrical mirror followed by an asymmetrically cut curved-crystal monochromator. This paper presents details of the optimization of the wiggler source for crystallography, gives a description of the beamline configuration, and discusses the reasons for the choices made

The At-Wavelength Metrology Facility at BESSY-II

Directory of Open Access Journals (Sweden)

Franz Schäfers

2016-02-01

Full Text Available The At-Wavelength Metrology Facility at BESSY-II is dedicated to short-term characterization of novel UV, EUV and XUV optical elements, such as diffraction gratings, mirrors, multilayers and nano-optical devices like reflection zone plates. It consists of an Optics Beamline PM-1 and a Reflectometer in a clean-room hutch as a fixed end station. The bending magnet Beamline is a Plane Grating Monochromator beamline (c-PGM equipped with an SX700 monochromator. The beamline is specially tailored for efficient high-order suppression and stray light reduction. The versatile 11-axes UHV-Reflectometer can house life-sized optical elements, which are fully adjustable and of which the reflection properties can be measured in the full incidence angular range as well as in the full azimuthal angular range to determine polarization properties.

Multiple wavelength multitimescale optical absorption system

International Nuclear Information System (INIS)

Lubis, R.; Allan, D.; Hodgson, B.W.; Swallow, A.J.

1992-01-01

A new workstation for pulse radiolysis studies has been developed for the Paterson Institute Linear Accelerator Laboratory. It is particularly suited to the study of materials available only in limited quantities. The analysing light beam is dispersed into a plane spectrum by a McPherson 270 monochromator and focused down to a line spectrum by a rod lens. The spectral intensity distribution is sampled by a linear array of optical fibres which conduct the light to photodiodes. A preamplifier unit amplifies and buffers the diode photocurrent signal which then passes to the main electronics unit incorporating further amplification stages, filters, backing-off of the background photocurrent, analog-to-digital conversion, data storage memory and a computer interface. All control of the electronic system is performed from a computer equipped with appropriate software. The system has 10 channels of spectral bandwidth 16 nm, a useful spectral response from 350 nm to 1 μm with a high signal-to-noise ratio, signal sampling rates from 20 MHz to 2 kHz and 8 kbyte of local memory for each channel. (author)

Multiple wavelength multitimescale optical absorption system

Science.gov (United States)

Lubis, R.; Allan, D.; Hodgson, B. W.; Swallow, A. J.

A new workstation for pulse radiolysis studies has been developed for the Paterson Institute Linear Accelerator Laboratory. It is particularly suited to the study of materials available only in limited quantities. The analysing light beam is dispersed into a plane spectrum by a McPherson 270 monochromator and focused down to a line spectrum by a rod lens. The spectral intensity distribution is sampled by a linear array of optical fibres which conduct the light to photodiodes. A preamplifier unit amplifies and buffers the diode photocurrent signal which then passes to the main electronics unit incorporating further amplification stages, filters, backing-off of the background photocurrent, analog-to-digital conversion, data storage memory and a computer interface. All control of the electronic system is performed from a computer equipped with appropriate software. The system has 10 channels of spectral bandwidth 16 nm, a useful spectral response from 350 nm to 1 μm with a high signal-to-noise ratio, signal sampling rates from 20 MHz to 2 kHz and 8 kbyte of local memory for each channel.

Update on VUV beamlines

International Nuclear Information System (INIS)

Waldhauer, A.

1985-01-01

On the building 131 mezzanine a new station, the 18 degree line, is planned for Beam Line III that will cover the photon energy range from 5 to 50 eV with high resolution and good flux. This station will use the Seya-Namioka monochromator that is currently in use on the 8 degree line, along with new input optics including a Silicon Carbide mirror as the first optical element. The overall flux should be higher that on the current 8 degree line at all photon energies, especially above 25 eV. Procurement has started and installation of the major components will occur during the winter and spring of 1986 with beam available to users in the fall of 1986. The Seya-Namioka monochromator will be replaced on Beam Line I by a toroidal grating monochromator (TGM). This TGM will cover the photon energy range from 9 to 170 eV and will use the existing M 0 mirror, with new M 1 and refocussing mirrors. The support frame will be designed to compensate for the instability of the slab which plagues the current 8 degree line, so the resolution should be limited by the monochromator and not the location of the beam line. The TGM is scheduled to arrive during the summer of 1986

Evolution of Instrumentation for UV-Visible Spectrophotometry. Part I.

Science.gov (United States)

Altemose, Ines R.

1986-01-01

Traces the development of instruments used in spectrophotometry. Discusses how spectrophotometric measurements are made. Describes the color comparator, the filter photometer, and the spectrophotometer. Outlines the evolution of optical systems, including light sources, the monochromator, the photodetector, double-beam optics, and split-beam…

Neutron monochromators of BeO, MgO and ZnO single crystals

Science.gov (United States)

Adib, M.; Habib, N.; Bashter, I. I.; Morcos, H. N.; El-Mesiry, M. S.; Mansy, M. S.

2014-05-01

The monochromatic features of BeO, MgO and ZnO single crystals are discussed in terms of orientation, mosaic spread, and thickness within the wavelength band from 0.05 up to 0.5 nm. A computer program MONO, written in “FORTRAN”, has been developed to carry out the required calculations. Calculation shows that a 5 mm thick MgO single crystal cut along its (2 0 0) plane having mosaic spread of 0.5° FWHM has the optimum parameters when it is used as a neutron monochromator. Moreover, at wavelengths shorter than 0.24 nm the reflected monochromatic neutrons are almost free from the higher order ones. The same features are seen with BeO (0 0 2) with less reflectivity than that of the former. Also, ZnO cut along its (0 0 2) plane is preferred over the others only at wavelengths longer than 0.20 nm. When the selected monochromatic wavelength is longer than 0.24 nm, the neutron intensities of higher orders from a thermal reactor flux are higher than those of the first-order one. For a cold reactor flux, the first order of BeO and MgO single crystals is free from the higher orders up to 0.4 nm, and ZnO at wavelengths up to 0.5 nm.

Precision mechanical structure of an ultra-high-resolution spectrometer for inelastic X-ray scattering instrument

Science.gov (United States)

Shu, Deming; Shvydko, Yuri; Stoupin, Stanislav A.; Khachatryan, Ruben; Goetze, Kurt A.; Roberts, Timothy

2015-04-14

A method and an ultrahigh-resolution spectrometer including a precision mechanical structure for positioning inelastic X-ray scattering optics are provided. The spectrometer includes an X-ray monochromator and an X-ray analyzer, each including X-ray optics of a collimating (C) crystal, a pair of dispersing (D) element crystals, anomalous transmission filter (F) and a wavelength (W) selector crystal. A respective precision mechanical structure is provided with the X-ray monochromator and the X-ray analyzer. The precision mechanical structure includes a base plate, such as an aluminum base plate; positioning stages for D-crystal alignment; positioning stages with an incline sensor for C/F/W-crystal alignment, and the positioning stages including flexure-based high-stiffness structure.

Beryllium, zinc and lead single crystals as a thermal neutron monochromators

Energy Technology Data Exchange (ETDEWEB)

Adib, M.; Habib, N. [Reactor Physics Department, NRC, Atomic Energy Authority, Cairo (Egypt); Bashter, I.I. [Physics Department, Faculty of Science, Zagazig University (Egypt); Morcos, H.N.; El-Mesiry, M.S. [Reactor Physics Department, NRC, Atomic Energy Authority, Cairo (Egypt); Mansy, M.S., E-mail: drmohamedmansy88@hotmail.com [Physics Department, Faculty of Science, Zagazig University (Egypt)

2015-03-15

Highlights: •Monochromatic features of Be, Zn and Pb single crystals. •Calculations of neutron reflectivity using a computer program MONO. •Optimum mosaic spread, thickness and cutting plane of single crystals. -- Abstract: The monochromatic features of Be, Zn and Pb single crystals are discussed in terms of orientation, mosaic spread, and thickness within the wavelength band from 0.04 up to 0.5 nm. A computer program MONO written in “FORTRAN-77”, has been adapted to carry out the required calculations. Calculations show that a 5 mm thick of beryllium (HCP structure) single crystal cut along its (0 0 2) plane having 0.6° FWHM are the optimum parameters when it is used as a monochromator with high reflected neutron intensity from a thermal neutron flux. Furthermore, at wavelengths shorter than 0.16 nm it is free from the accompanying higher order ones. Zinc (HCP structure) has the same parameters, with intensity much less than the latter. The same features are seen with lead (FCC structure) cut along its (3 1 1) plane with less reflectivity than the former. However, Pb (3 1 1) is more preferable than others at neutron wavelengths ⩽ 0.1 nm, since the glancing angle (θ ∼ 20°) is more suitable to carry out diffraction experiments. For a cold neutron flux, the first-order neutrons reflected from beryllium is free from the higher orders up to 0.36 nm. While for Zn single crystal is up to 0.5 nm.

Holographic Optical Elements Recorded in Silver Halide Sensitized Gelatin Emulsions. Part 2. Reflection Holographic Optical Elements

Science.gov (United States)

Kim, Jong Man; Choi, Byung So; Choi, Yoon Sun; Kim, Jong Min; Bjelkhagen, Hans I.; Phillips, Nicholas J.

2002-03-01

Silver halide sensitized gelatin (SHSG) holograms are similar to holograms recorded in dichromated gelatin (DCG), the main recording material for holographic optical elements (HOEs). The drawback of DCG is its low energetic sensitivity and limited spectral response. Silver halide materials can be processed in such a way that the final hologram will have properties like a DCG hologram. Recently this technique has become more interesting since the introduction of new ultra-fine-grain silver halide (AgHal) emulsions. In particular, high spatial-frequency fringes associated with HOEs of the reflection type are difficult to construct when SHSG processing methods are employed. Therefore an optimized processing technique for reflection HOEs recorded in the new AgHal materials is introduced. Diffraction efficiencies over 90% can be obtained repeatably for reflection diffraction gratings. Understanding the importance of a selective hardening process has made it possible to obtain results similar to conventional DCG processing. The main advantage of the SHSG process is that high-sensitivity recording can be performed with laser wavelengths anywhere within the visible spectrum. This simplifies the manufacturing of high-quality, large-format HOEs, also including high-quality display holograms of the reflection type in both monochrome and full color.

New optical scheme for differential measurements of diffraction reflection intensity on X-radiation sliding incidence

International Nuclear Information System (INIS)

Golovin, A.L.; Mas', E.T.

1989-01-01

An X-ray optical scheme for differential measurements of X-ray diffraction under sliding incidence conditions is proposed and an attachment design realizng this scheme, using standard equipment, is described. The main feature of the scheme is the following: collimation according to the Bragg angle is carried out for the reflected beam rather than the incident one. Goniometers can be used from DRON, TRS, GS-5 and other spectrometers. The goniometer head carrying the sample is standard, it is a part of the DRON, TRS and DTS. The crystal analyzer is fixed on the attachment. The angular position of the crystal monochromator is controlled by an inductive sensor. The experimental differential curves of X-ray diffraction under conditions of sliding incidence, taken for a silicon crystal having the 111 orientation, are given as well

Three-energy focusing Laue monochromator for the diamond light source x-ray pair distribution function beamline I15-1

Energy Technology Data Exchange (ETDEWEB)

Sutter, John P., E-mail: john.sutter@diamond.ac.uk; Chater, Philip A.; Hillman, Michael R.; Keeble, Dean S.; Wilhelm, Heribert [Diamond Light Source Ltd, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 0DE (United Kingdom); Tucker, Matt G. [Diamond Light Source Ltd, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 0DE (United Kingdom); ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0QX (United Kingdom)

2016-07-27

The I15-1 beamline, the new side station to I15 at the Diamond Light Source, will be dedicated to the collection of atomic pair distribution function data. A Laue monochromator will be used consisting of three silicon crystals diffracting X-rays at a common Bragg angle of 2.83°. The crystals use the (1 1 1), (2 2 0), and (3 1 1) planes to select 40, 65, and 76 keV X-rays, respectively, and will be bent meridionally to horizontally focus the selected X-rays onto the sample. All crystals will be cut to the same optimized asymmetry angle in order to eliminate image broadening from the crystal thickness. Finite element calculations show that the thermal distortion of the crystals will affect the image size and bandpass.

Three-energy focusing Laue monochromator for the diamond light source x-ray pair distribution function beamline I15-1

International Nuclear Information System (INIS)

Sutter, John P.; Chater, Philip A.; Hillman, Michael R.; Keeble, Dean S.; Wilhelm, Heribert; Tucker, Matt G.

2016-01-01

The I15-1 beamline, the new side station to I15 at the Diamond Light Source, will be dedicated to the collection of atomic pair distribution function data. A Laue monochromator will be used consisting of three silicon crystals diffracting X-rays at a common Bragg angle of 2.83°. The crystals use the (1 1 1), (2 2 0), and (3 1 1) planes to select 40, 65, and 76 keV X-rays, respectively, and will be bent meridionally to horizontally focus the selected X-rays onto the sample. All crystals will be cut to the same optimized asymmetry angle in order to eliminate image broadening from the crystal thickness. Finite element calculations show that the thermal distortion of the crystals will affect the image size and bandpass.

Synthesis and optical properties of biphenylene ethynylene co ...

Indian Academy of Sciences (India)

The absorption and photoluminescence spectra of the polymers, P1, P2 and P5 showed .... Microanalyses were performed at the ... signals were passed through a second monochromator .... 3.1 Synthesis and characterization of polymers and.

Ratiometric, filter-free optical sensor based on a complementary metal oxide semiconductor buried double junction photodiode.

Science.gov (United States)

Yung, Ka Yi; Zhan, Zhiyong; Titus, Albert H; Baker, Gary A; Bright, Frank V

2015-07-16

We report a complementary metal oxide semiconductor integrated circuit (CMOS IC) with a buried double junction (BDJ) photodiode that (i) provides a real-time output signal that is related to the intensity ratio at two emission wavelengths and (ii) simultaneously eliminates the need for an optical filter to block Rayleigh scatter. We demonstrate the BDJ platform performance for gaseous NH3 and aqueous pH detection. We also compare the BDJ performance to parallel results obtained by using a slew scanned fluorimeter (SSF). The BDJ results are functionally equivalent to the SSF results without the need for any wavelength filtering or monochromators and the BDJ platform is not prone to errors associated with source intensity fluctuations or sensor signal drift. Copyright © 2015 Elsevier B.V. All rights reserved.

Anisotropic elasticity of silicon and its application to the modelling of X-ray optics

International Nuclear Information System (INIS)

Zhang, Lin; Barrett, Raymond; Cloetens, Peter; Detlefs, Carsten; Sanchez del Rio, Manuel

2014-01-01

Anisotropic elasticity of single-crystal silicon, applications to modelling of a bent X-ray mirror, and thermal deformation of a liquid-nitrogen-cooled monochromator crystal are presented. The crystal lattice of single-crystal silicon gives rise to anisotropic elasticity. The stiffness and compliance coefficient matrix depend on crystal orientation and, consequently, Young’s modulus, the shear modulus and Poisson’s ratio as well. Computer codes (in Matlab and Python) have been developed to calculate these anisotropic elasticity parameters for a silicon crystal in any orientation. These codes facilitate the evaluation of these anisotropy effects in silicon for applications such as microelectronics, microelectromechanical systems and X-ray optics. For mechanically bent X-ray optics, it is shown that the silicon crystal orientation is an important factor which may significantly influence the optics design and manufacturing phase. Choosing the appropriate crystal orientation can both lead to improved performance whilst lowering mechanical bending stresses. The thermal deformation of the crystal depends on Poisson’s ratio. For an isotropic constant Poisson’s ratio, ν, the thermal deformation (RMS slope) is proportional to (1 + ν). For a cubic anisotropic material, the thermal deformation of the X-ray optics can be approximately simulated by using the average of ν 12 and ν 13 as an effective isotropic Poisson’s ratio, where the direction 1 is normal to the optic surface, and the directions 2 and 3 are two normal orthogonal directions parallel to the optical surface. This average is independent of the direction in the optical surface (the crystal plane) for Si(100), Si(110) and Si(111). Using the effective isotropic Poisson’s ratio for these orientations leads to an error in thermal deformation smaller than 5.5%

Anisotropic elasticity of silicon and its application to the modelling of X-ray optics

Energy Technology Data Exchange (ETDEWEB)

Zhang, Lin, E-mail: zhang@esrf.fr; Barrett, Raymond; Cloetens, Peter; Detlefs, Carsten; Sanchez del Rio, Manuel [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, BP 220, 38043 Grenoble (France)

2014-04-04

Anisotropic elasticity of single-crystal silicon, applications to modelling of a bent X-ray mirror, and thermal deformation of a liquid-nitrogen-cooled monochromator crystal are presented. The crystal lattice of single-crystal silicon gives rise to anisotropic elasticity. The stiffness and compliance coefficient matrix depend on crystal orientation and, consequently, Young’s modulus, the shear modulus and Poisson’s ratio as well. Computer codes (in Matlab and Python) have been developed to calculate these anisotropic elasticity parameters for a silicon crystal in any orientation. These codes facilitate the evaluation of these anisotropy effects in silicon for applications such as microelectronics, microelectromechanical systems and X-ray optics. For mechanically bent X-ray optics, it is shown that the silicon crystal orientation is an important factor which may significantly influence the optics design and manufacturing phase. Choosing the appropriate crystal orientation can both lead to improved performance whilst lowering mechanical bending stresses. The thermal deformation of the crystal depends on Poisson’s ratio. For an isotropic constant Poisson’s ratio, ν, the thermal deformation (RMS slope) is proportional to (1 + ν). For a cubic anisotropic material, the thermal deformation of the X-ray optics can be approximately simulated by using the average of ν{sub 12} and ν{sub 13} as an effective isotropic Poisson’s ratio, where the direction 1 is normal to the optic surface, and the directions 2 and 3 are two normal orthogonal directions parallel to the optical surface. This average is independent of the direction in the optical surface (the crystal plane) for Si(100), Si(110) and Si(111). Using the effective isotropic Poisson’s ratio for these orientations leads to an error in thermal deformation smaller than 5.5%.

Design of the soft x-ray tomography beamline at Taiwan photon source

Energy Technology Data Exchange (ETDEWEB)

Su, Yi-Jr, E-mail: su.yj@nsrrc.org.tw; Fu, Huang-Wen; Chung, Shih-Chun; Fung, Hok-Sum; Liu, Din-Goa; Huang, Liang-Jen; Yan, Hong-Yi; Chou, Yu-Ching; Yin, Gung-Chian; Lai, Lee-Jene [National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu, Taiwan (China)

2016-07-27

The optical design of the varied-line-spacing plane-grating monochromator for transmission full-field imaging of frozen-hydrated biological samples at NSRRC is presented. This monochromator consists of a plane mirror and three interchangeable gratings with groove densities 600, 1200 and 2400 l/mm to cover the energy range 260 – 2600 eV. The groove parameters of the varied-line-spacing plane gratings are designed to minimize the effect of coma and spherical aberration to maintain the exit slit in focus for any value of incident angle. All parameters of optical components at the beamline are verified with a ray-tracing method. In the beamline design, the calculated results from the ray-tracing codes and the expected performances are discussed.

Structure and properties of optical-discharge plasma in CO2-laser beam near target surface

Science.gov (United States)

Danshchikov, Ye. V.; Dymshakov, V. A.; Lebedev, F. V.; Ryazanov, A. V.

1986-05-01

An experimental study of optical-discharge plasma in a CO2-laser beam at a target surface was made for the purpose of exploring the not yet understood role of this plasma in the laser-target interaction process. Such a plasma was produced by means of a quasi-continuous CO2-laser with an unstable resonator, its power being maintained constant for 1 ms periods. Its radiation was focused on the surfaces of thick and seeding thin Al, Ti, and Ta targets inclined at an approximately 70 deg. angle to the beam, inside a hermetic chamber containing air, argon, or helium under atmospheric pressure. The radiation intensity distribution over the focal plane and the nearest caustic surface in the laser beam was measured along with the plasma parameters, the latter by the methods of spectral analysis and photoelectric recording. The instrumentation for this purpose included an MDR-3 monochromator with an entrance slit, a double electron-optical converter, a memory oscillograph, and an SI-10-30 ribbon lamp as radiation reference standard. The results yielded integral diametral intensity distributions of the emission lines Ti-II (457.2 nm), Ti-I (464 nm), Ar-II (462 nm), radial and axial temperature profiles of optical discharge in metal vapor in surrounding gas, and the radial temperature profile of irradiated metal surface at successive instants of time. The results reveal marked differences between the structures and the properties of optical-discharge plasma in metal vapor and in surrounding gas, optical discharge in the former being characterized by localization within the laser beam and optical discharge in the latter being characterized by a drift away from the target.

Supplemental shielding of BMIT SOE-1 at the Canadian Light Source

International Nuclear Information System (INIS)

Bassey, Bassey; Abueidda, Abdallah; Cubbon, Grant; Street, Darin; Sabbir Ahmed, Asm; Wysokinski, Tomasz W.; Belev, George; Chapman, Dean

2014-01-01

High field superconducting wiggler beamlines present shielding challenges due to the high critical energy of the synchrotron spectrum. An unexpected, but predictable, weakness in the secondary optical enclosure (SOE-1) was discovered on the BioMedical Imaging and Therapy (BMIT) insertion device (ID) beamline 05ID-2 at the Canadian Light Source (CLS). SOE-1 is a monochromatic beam hutch; the beam in it is supplied by three monochromators housed in an upstream primary optical enclosure (POE-3). The initial shielding of SOE-1 was based on a shielding calculation against target scattered and direct monochromatic (fundamental and harmonics) beams from the monochromators in POE-3. During a radiation survey of the hutch, radiation above the expected level was measured at the downstream end of SOE-1. This increment in radiation level is attributed to scattered white beam into SOE-1 by a K-Edge subtraction (KES) monochromator's crystal (a single crystal monochromator) in POE-3. Though this is peculiar to the BMIT beamline 05ID-2, it may not be uncommon for other beamlines that use single crystal monochromators. Calculations of the level of expected leakage radiation due to the scattered white beam arriving on the downstream wall of the SOE-1 are presented, as well as the supplemental shielding that will reduce the leakage to less than 1 μSv/h as required at the CLS. Also presented are the installed supplemental shielding, and a comparison of the calculations and measurements of the dose rates on the back wall of SOE-1 End Wall, before and after installation of the supplemental shielding. - Highlights: • We discovered an unexpected weakness in the shielding of BMIT SOE-1 End Wall. • We predicted the source of the weakness-scattering of white beam into SOE-1. • White beam scattered into SOE-1 by the crystal of a single crystal monochromator. • We calculated and installed the required supplemental shielding. • With the installed supplemental shielding, we have

Two (and more) sharp X-ray wavelengths in one beam

Czech Academy of Sciences Publication Activity Database

Hrdý, Jaromír; Hrdá, Jaromíra; Oberta, Peter; Pacherová, Oliva

2016-01-01

Roč. 807, Jan (2016), s. 61-63 ISSN 0168-9002 Institutional support: RVO:68378271 Keywords : dual energy * imaging * monochromator Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.362, year: 2016

Neutron monochromators of BeO, MgO and ZnO single crystals

Energy Technology Data Exchange (ETDEWEB)

Adib, M.; Habib, N. [Reactor Physics Department, NRC, AEAE, Cairo (Egypt); Bashter, I.I. [Physics Department, Faculty of Science, Zagazig University (Egypt); Morcos, H.N.; El-Mesiry, M.S. [Reactor Physics Department, NRC, AEAE, Cairo (Egypt); Mansy, M.S., E-mail: mohamedmansy_np@yahoo.com [Physics Department, Faculty of Science, Zagazig University (Egypt)

2014-05-21

The monochromatic features of BeO, MgO and ZnO single crystals are discussed in terms of orientation, mosaic spread, and thickness within the wavelength band from 0.05 up to 0.5 nm. A computer program MONO, written in “FORTRAN”, has been developed to carry out the required calculations. Calculation shows that a 5 mm thick MgO single crystal cut along its (2 0 0) plane having mosaic spread of 0.5° FWHM has the optimum parameters when it is used as a neutron monochromator. Moreover, at wavelengths shorter than 0.24 nm the reflected monochromatic neutrons are almost free from the higher order ones. The same features are seen with BeO (0 0 2) with less reflectivity than that of the former. Also, ZnO cut along its (0 0 2) plane is preferred over the others only at wavelengths longer than 0.20 nm. When the selected monochromatic wavelength is longer than 0.24 nm, the neutron intensities of higher orders from a thermal reactor flux are higher than those of the first-order one. For a cold reactor flux, the first order of BeO and MgO single crystals is free from the higher orders up to 0.4 nm, and ZnO at wavelengths up to 0.5 nm. - Highlights: • Monochromatic features of BeO, MgO and ZnO single crystals. • Calculations of neutron reflectivity using a computer program MONO. • Optimum mosaic spread, thickness and cutting plane of single crystals.

Use of zero order diffraction of a grating monochromator towards convenient and sensitive detection of fluorescent analytes in multi fluorophoric systems

Science.gov (United States)

Panigrahi, Suraj Kumar; Mishra, Ashok Kumar

2018-02-01

White light excitation fluorescence (WLEF) is known to possess analytical advantage in terms of enhanced sensitivity and facile capture of the entire fluorescence spectral signature of multi component fluorescence systems. Using the zero order diffraction of the grating monochromator on the excitation side of a commercial spectrofluorimeter, it has been shown that WLEF spectral measurements can be conveniently carried out. Taking analyte multi-fluorophoric systems like (i) drugs and vitamins spiked in urine sample, (ii) adulteration of extra virgin olive oil with olive pomace oil and (iii) mixture of fabric dyes, it was observed that there is a significant enhancement of measurement sensitivity. The total fluorescence spectral response could be conveniently analysed using PLS2 regression. This work brings out the ease of the use of a conventional fluorimeter for WLEF measurements.

Numerical simulation of distorted crystal Darwin width

International Nuclear Information System (INIS)

Wang Li; Xu Zhongmin; Wang Naxiu

2012-01-01

A new numerical simulation method according to distorted crystal optical theory was used to predict the direct-cooling crystal monochromator optical properties(crystal Darwin width) in this study. The finite element analysis software was used to calculate the deformed displacements of DCM crystal and to get the local reciprocal lattice vector of distorted crystal. The broadening of direct-cooling crystal Darwin width in meridional direction was estimated at 4.12 μrad. The result agrees well with the experimental data of 5 μrad, while it was 3.89 μrad by traditional calculation method of root mean square (RMS) of the slope error in the center line of footprint. The new method provides important theoretical support for designing and processing of monochromator crystal for synchrotron radiation beamline. (authors)

Exploratory heat transfer studies on critical elements of a proposed 6 GeV synchrotron

International Nuclear Information System (INIS)

Kuzay, T.M.; Knapp, G.S.

1985-11-01

Certain types of insertion devices for angiography, can produce extraordinarily large heat fluxes on critical components of a synchrotron beam line and its optics. The shutters, beam splitters, filters, and the first-stage monochromators all are subjected to large fluxes of radiation. The cooling requirements of such beam line components are approached in a comprehensive manner to identify the governing parameters from first principles. Analytical techniques have been used to study various methods of handling the heat loads using both liquid metal and water coolants for various potential heated geometries. It is found that when properly designed, liquid metal cooling can be much more efficient. In addition, composites and low Z surfaces have been considered. Also investigated are the heat transfer problems of the optical stages and rotating monochromators

Exploratory heat transfer studies on critical elements of a proposed 6 GeV synchrotron

International Nuclear Information System (INIS)

Kuzay, T.M.; Knapp, G.S.

1986-01-01

Certain types of insertion devices for angiography can produce extraordinarily large heat fluxes on critical components of a synchrotron beam line and its optics. The shutters, beam splitters, filters, and the first-stage monochromators all are subjected to large fluxes of radiation. The cooling requirements of such beam line components are approached in a comprehensive manner to identify the governing parameters from first principles. Analytical techniques have been used to study various methods of handling the heat loads using both liquid metal and water coolants for various potential heated geometries. It is found that when properly designed, liquid metal cooling can be much more efficient. In addition, composites and low Z surfaces have been considered. Also investigated are the heat transfer problems of the optical stages and rotating monochromators

Laboratory-based recording of holographic fine structure in X-ray absorption anisotropy using polycapillary optics

Energy Technology Data Exchange (ETDEWEB)

Dabrowski, K.M. [Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Krakow (Poland); Korecki, P., E-mail: pawel.korecki@uj.edu.pl [Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Krakow (Poland)

2012-08-15

Highlights: Black-Right-Pointing-Pointer Holographic fine structures in X-ray absorption recorded using a tabletop setup. Black-Right-Pointing-Pointer Setup based on polycapillary collimating optics and an HOPG crystal. Black-Right-Pointing-Pointer Demonstration of element sensitivity by detection of X-ray fluorescence. Black-Right-Pointing-Pointer Potential of laboratory-based experiments for heavily doped crystals and thin films. - Abstract: A tabletop setup composed of a collimating polycapillary optics and a highly oriented pyrolytic graphite monochromator (HOPG) was characterized and used for recording two-dimensional maps of X-ray absorption anisotropy (XAA). XAA originates from interference of X-rays directly inside the sample. Depending on experimental conditions, fine structures in XAA can be interpreted in terms of X-ray holograms or X-ray standing waves and can be used for an element selective atomic-resolved structural analysis. The implementation of polycapillary optics resulted in a two-order of magnitude gain in the radiant intensity (photons/s/solid angle) as compared to a system without optics and enabled efficient recording of XAA with a resolution of 0.15 Degree-Sign for Mo K{alpha} radiation. Element sensitivity was demonstrated by acquisition of distinct XAA signals for Ga and As atoms in a GaAs (1 1 1) wafer by using X-ray fluorescence as a secondary signal. These results indicate the possibility of performing laboratory-based XAA experiments for heavily doped single crystals or thin films. So far, because of the weak holographic modulation of XAA, such experiments could be only performed using synchrotron radiation.

Interface of the transport systems research vehicle monochrome display system to the digital autonomous terminal access communication data bus

Science.gov (United States)

Easley, W. C.; Tanguy, J. S.

1986-01-01

An upgrade of the transport systems research vehicle (TSRV) experimental flight system retained the original monochrome display system. The original host computer was replaced with a Norden 11/70, a new digital autonomous terminal access communication (DATAC) data bus was installed for data transfer between display system and host, while a new data interface method was required. The new display data interface uses four split phase bipolar (SPBP) serial busses. The DATAC bus uses a shared interface ram (SIR) for intermediate storage of its data transfer. A display interface unit (DIU) was designed and configured to read from and write to the SIR to properly convert the data from parallel to SPBP serial and vice versa. It is found that separation of data for use by each SPBP bus and synchronization of data tranfer throughout the entire experimental flight system are major problems which require solution in DIU design. The techniques used to accomplish these new data interface requirements are described.

Luminescent unit computerization to research spectral characteristics of fine film alkali halide crystal

International Nuclear Information System (INIS)

Zhalimbetov, T.; Zhabetov, A.; Moldagaliev, A.; Sarmukhanov, E.; Shunkeev, K.; Shunkeev, S.; Abdullin, K.; Tokmoldin, C.

2002-01-01

The fundamental optical absorption of ion crystals characterizes the creation of different free low energetic electronic excitation (the excitons and electron-hole pairs), but their straight registration is not possible because of incommensurable big absorption factor of alkali halide monocrystals. So to registration the spectrums of alkali halide monocrystal very fine layers are necessary. We have received fine films of Nal and KCl in system of KCl-Nal-KCl, KCl-KI-KCl on the base of universal vacuum post VUP-4, VUP-5 by thermal evaporation. A unique spectral unit has been created For this on the basic the SDL-2 complex. Complex consists of radiator, systems of condensers, monochromators MDR-12 and MDR-23, receivers of radiation, controller by unit. Connect and control of monochromators by means of IBM-compatible computer has been created. Kinematics schemes of monochromators provide consequent removing on output slot of monochromatic radiation in operating range of each diffraction lattice and indication its wavelength. The tumbling diffraction lattices is done the crossbar engines SHDR-711. For this special plate of control and block of reinforcement for crossbar engines in monochromators MDR-12 and MDR-23 are designed and constructed. Created controller of monochromators consists of double cascade preamplifier on transistors n-p-n type (815G) and logical scheme, constructed on summers and K555 series triggers. The preamplifier is used for reinforcement of signal to available amplifier on transistors KT837D. The logical scheme reduces the number of used categories of bidirectional port and enables unhooking the feeding to the windings of crossbar engine at conservation of previous combination of signals. The connection controller of monochromators is done through controller of port of computer with use the parallel interface. For installing computerized system of collection and data processing is provided marketed by means of modern object-oriented programming

A high resolution powder diffractometer using focusing optics

Indian Academy of Sciences (India)

E-mail: siruguri@csr.ernet.in. Abstract. In this paper, we describe the design, construction and performance of a new high resolution neutron powder diffractometer that has been installed at the Dhruva reactor, Trombay, India. The instrument employs novel design concepts like the use of bent, perfect crystal monochromator ...

Spectroscopic studies of xenon EUV emission in the 40-80 nm wavelength range using an absolutely calibrated monochromator

Energy Technology Data Exchange (ETDEWEB)

Merabet, H [Mathematic and Sciences Unit, Dhofar University, Salalah 211, Sultanate of (Oman); Bista, R [Department of Physics, University of Nevada Reno, Reno, NV 89557 (United States); Bruch, R [Department of Physics, University of Nevada Reno, Reno, NV 89557 (United States); Fuelling, S [Department of Physics, University of Nevada Reno, Reno, NV 89557 (United States)

2007-03-01

We have measured and identified numerous Extreme UltraViolet (EUV) radiative line structures arising from xenon (Xe) ions in charge state q = 1 to 10 in the wavelength range 40-80 nm. To obtain reasonable intensities of different charged Xe ions, we have used a compact microwave plasma source which was designed and developed at the Lawrence Berkeley National Laboratory (LBNL). The EUV emission of the ECR plasma has been measured by a 1.5 m grazing incidence monochromator that was absolutely calibrated in the 10-80 nm wavelength range using well known and calibrated EUV light at the Advanced Light Source (ALS), LBNL. This calibration has enabled us to determine absolute intensities of previously measured EUV radiative lines in the wavelengths regions investigated for different ionization stages of Xe. In addition, emission spectra of xenon ions for corresponding measured lines have been calculated. The calculations have been carried out within the relativistic Hartree-Fock (HF) approximation. Results of calculations are found to be in good agreement with current and available experimental and theoretical data.

Design of doubly focusing, tunable (5 to 30 keV), wide-bandpass optics made from layered synthetic microstructures

International Nuclear Information System (INIS)

Bilderback, D.H.; Lairson, B.M.; Barbee, T.W. Jr.; Ice, G.E.; Sparks, C.J. Jr.

1982-01-01

Layered Synthetic Microstructures (LSMs) show great promise as focusing, high-throughput, hard x-ray monochromators. Experimental reflectivity vs. energy curves have been obtained on carbon-tungsten and carbon-molybdenum LSMs of up to 260 layers in thickness. Reflectivities for three flat LSMs with different bandpasses were 70% with δE/E = 5.4%, 66% with δE/E = 1.4%, and 19% with δE/E = 0.6%. A new generation of variable bandwidth optics using two successive LSMs is proposed. The first element will be an LSM deposited on a substrate that can be water cooled as it intercepts direct radiation from a storage ring. It can be bent for vertical focusing. The bandpass can be adjusted by choosing interchangeable first elements from an assortment of LSM's with different bandpasses (for example, δE/E = 0.005, 0.01, 0.02, 0.05, 0.1). The second LSM will consist of a multilayered structure with a 10% bandpass built onto a flexible substrate that can be bent for sagittal focusing. The result will be double focusing optics with an adjustable energy bandpass that are tunable from 5 to 30 keV

The EMIL project at BESSY II: Beamline design and performance

Energy Technology Data Exchange (ETDEWEB)

Hendel, Stefan, E-mail: stefan.hendel@helmholtz-berlin.de; Schäfers, Franz; Reichardt, Gerd; Scheer, Michael; Bahrdt, Johannes; Lips, Klaus [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489 Berlin (Germany); Hävecker, Michael [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489 Berlin (Germany); MPI for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr (Germany)

2016-07-27

The Energy Materials In-Situ Laboratory Berlin (EMIL) at BESSY-II is currently under construction. Two canted undulators for soft- and hard X-rays will be installed into the BESSY II storage ring in one straight section, complex beamlines with more than twenty optical elements will be set up and a new laboratory building attached to BESSY II will host three endstations and a large UHV-transfer system connecting various HV- and UHV-deposition systems. The undulators, UE48 and U17, provide a broad energy spectrum of 80 - 10000 eV, of which the harder radiation (>700 eV) is provided by a cryogenic in-vacuum device. Three monochromators (two plane grating monochromators (PGM) and one LN{sub 2}-cooled double crystal monochromator (DCM)) disperse the radiation into separate pathways of 65 m length, while downstream of the monochromators split-mirror chambers distribute the photon beam to one (or simultaneously to two) of five upcoming endstations. Three of these endstations are designed for the full energy range with spatial overlap of the soft and hard foci, whereas one endstation (PEEM) uses only the soft and another one (PINK) only the hard branch, respectively.

Time-resolved optical spectrometer based on a monolithic array of high-precision TDCs and SPADs

Science.gov (United States)

Tamborini, Davide; Markovic, Bojan; Di Sieno, Laura; Contini, Davide; Bassi, Andrea; Tisa, Simone; Tosi, Alberto; Zappa, Franco

2013-12-01

We present a compact time-resolved spectrometer suitable for optical spectroscopy from 400 nm to 1 μm wavelengths. The detector consists of a monolithic array of 16 high-precision Time-to-Digital Converters (TDC) and Single-Photon Avalanche Diodes (SPAD). The instrument has 10 ps resolution and reaches 70 ps (FWHM) timing precision over a 160 ns full-scale range with a Differential Non-Linearity (DNL) better than 1.5 % LSB. The core of the spectrometer is the application-specific integrated chip composed of 16 pixels with 250 μm pitch, containing a 20 μm diameter SPAD and an independent TDC each, fabricated in a 0.35 μm CMOS technology. In front of this array a monochromator is used to focus different wavelengths into different pixels. The spectrometer has been used for fluorescence lifetime spectroscopy: 5 nm spectral resolution over an 80 nm bandwidth is achieved. Lifetime spectroscopy of Nile blue is demonstrated.

Liquid metal cooling of synchrotron optics

International Nuclear Information System (INIS)

Smither, R.K.

1993-01-01

The installation of insertion devices at existing synchrotron facilities around the world has stimulated the development of new ways to cool the optical elements in the associated x-ray beamlines. Argonne has been a leader in the development of liquid metal cooling for high heat load x-ray optics for the next generation of synchrotron facilities. The high thermal conductivity, high volume specific heat, low kinematic viscosity, and large working temperature range make liquid metals a very efficient heat transfer fluid. A wide range of liquid metals were considered in the initial phase of this work. The most promising liquid metal cooling fluid identified to date is liquid gallium, which appears to have all the desired properties and the fewest number of undesired features of the liquid metals examined. Besides the special features of liquid metals that make them good heat transfer fluids, the very low vapor pressure over a large working temperature range make liquid gallium an ideal cooling fluid for use in a high vacuum environment. A leak of the liquid gallium into the high vacuum and even into very high vacuum areas will not result in any detectable vapor pressure and may even improve the vacuum environment as the liquid gallium combines with any water vapor or oxygen present in the system. The practical use of a liquid metal for cooling silicon crystals and other high heat load applications depends on having a convenient and efficient delivery system. The requirements for a typical cooling system for a silicon crystal used in a monochromator are pumping speeds of 2 to 5 gpm (120 cc per sec to 600 cc per sec) at pressures up to 100 psi. No liquid metal pump with these capabilities was available commercially when this project was started, so it was necessary to develop a suitable pump in house

In situ removal of carbon contamination from a chromium-coated mirror: ideal optics to suppress higher-order harmonics in the carbon K-edge region.

Science.gov (United States)

Toyoshima, Akio; Kikuchi, Takashi; Tanaka, Hirokazu; Mase, Kazuhiko; Amemiya, Kenta

2015-11-01

Carbon-free chromium-coated optics are ideal in the carbon K-edge region (280-330 eV) because the reflectivity of first-order light is larger than that of gold-coated optics while the second-order harmonics (560-660 eV) are significantly suppressed by chromium L-edge and oxygen K-edge absorption. Here, chromium-, gold- and nickel-coated mirrors have been adopted in the vacuum ultraviolet and soft X-ray branch beamline BL-13B at the Photon Factory in Tsukuba, Japan. Carbon contamination on the chromium-coated mirror was almost completely removed by exposure to oxygen at a pressure of 8 × 10(-2) Pa for 1 h under irradiation of non-monochromated synchrotron radiation. The pressure in the chamber recovered to the order of 10(-7) Pa within a few hours. The reflectivity of the chromium-coated mirror of the second-order harmonics in the carbon K-edge region (560-660 eV) was found to be a factor of 0.1-0.48 smaller than that of the gold-coated mirror.

A reflectivity profilometer for the optical characterisation of grade reflectivity mirrors in the 250 nm - 1100 nm spectral region

Energy Technology Data Exchange (ETDEWEB)

Colucci, Alessandro; Nichelatti, Enrico [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Innovazione

1998-04-01

It`s developed the prototype of an instrument that can be used for the optical characterisation of graded reflectivity mirrors at any wavelength in the spectral region from 250 nm to 1100 nm. The instrument utilises a high-pressure Xe arc lamp as light source. Light is spectrally filtered by means of a grating monochromator. The sample is illuminated with an image of the monochromator exit slit. After reflection from the sample, this image is projected onto a 1024-elements charge-coupled device linear array driven by a digital frame board and interfaced with a personal computer. It`s tested the instrument accuracy by comparing measurement results with the corresponding ones obtained by means of a laser scanning technique. Measurement Rms repeatability has been estimated to be approximately of 0.8%. [Italiano] E` stato sviluppato il prototipo di uno strumento per la catatterizzazione ottica di specchi a riflettivita` variabile, operante a qualsiasi lunghezza d`onda nell`intervallo spettrale da 250 nm a 1100 nm. La sorgente dello strumento e` una lampada ad arco allo Xenon ad alta pressione. La luce e` filtrata spettralmente per mezzo di un monocromatore a reticolo. Il campione viene illuminato da un`immagine della fenditura d`uscita del monocromatore. Dopo essere stata riflessa dal campione, questa immagine viene proiettata su un array CCD lineare a 1024 elementi, connesso elettronicamente a una scheda digitale e interfacciato a un personal computer. L`accuratezza dello strumento e` stata verificata confrontando alcune misure con le corrispondenti misure ottenute mediante una tecnica a scansione laser. La ripetibilita` RMS delle misure e` stata stimata essere circa dello 0.8%.

The high-energy x-ray diffraction and scattering beamline at the Canadian Light Source

Science.gov (United States)

Gomez, A.; Dina, G.; Kycia, S.

2018-06-01

The optical design for the high-energy x-ray diffraction and scattering beamline of the Brockhouse sector at the Canadian Light Source is described. The design is based on a single side-bounce silicon focusing monochromator that steers the central part of a high-field permanent magnet wiggler beam into the experimental station. Two different configurations are proposed: a higher energy resolution with vertical focusing and a lower energy resolution with horizontal and vertical focusing. The monochromator will have the possibility of mounting three crystals: one crystal optimized for 35 keV that focuses in the horizontal and vertical directions using reflection (1,1,1) and two other crystals both covering the energies above 40 keV: one with only vertical focusing and another one with horizontal and vertical focusing. The geometry of the last two monochromator crystals was optimized to use reflections (4,2,2) and (5,3,3) to cover the broad energy range from 40 to 95 keV.

A compact low cost “master–slave” double crystal monochromator for x-ray cameras calibration of the Laser MégaJoule Facility

Energy Technology Data Exchange (ETDEWEB)

Hubert, S., E-mail: sebastien.hubert@cea.fr; Prévot, V.

2014-12-21

The Alternative Energies and Atomic Energy Commission (CEA-CESTA, France) built a specific double crystal monochromator (DCM) to perform calibration of x-ray cameras (CCD, streak and gated cameras) by means of a multiple anode diode type x-ray source for the MégaJoule Laser Facility. This DCM, based on pantograph geometry, was specifically modeled to respond to relevant engineering constraints and requirements. The major benefits are mechanical drive of the second crystal on the first one, through a single drive motor, as well as compactness of the entire device. Designed for flat beryl or Ge crystals, this DCM covers the 0.9–10 keV range of our High Energy X-ray Source. In this paper we present the mechanical design of the DCM, its features quantitatively measured and its calibration to finally provide monochromatized spectra displaying spectral purities better than 98%.

Measurement of the electronic absorption coefficient for 57Co 14.4 keV gamma photons in aluminium using the Moessbauer effect as a monochromator

International Nuclear Information System (INIS)

Rajan, N.; Nigam, A.K.

1984-01-01

The total electronic absorption coefficient for 14.4 keV gamma photons in aluminium, has been measured experimentally, for the first time, using the Moessbauer effect as a monochromator. This data is important for the determination of background in Moessbauer recoilless fraction measurements especially if the energy of X-rays of the source host lattice lie near the 14.4 keV photon energy (e.g. in Rh and Pd) in which case electronic absorption coefficients should be known precisely. The coefficient obtained by interpolation from available values at other energies differ from our experimental value by as much as 20%. It is shown that this can lead to errors, in recoilless fraction values, which are far from negligible. The above absorption coefficient for aluminium was measured to be 11+-1 cm 2 /g. (orig.)

Contactless multiple wavelength photoplethysmographic imaging: a first step toward "spO2 camera" technology

NARCIS (Netherlands)

Wieringa, F.P.; Mastik, F.; Steen, A.F.W. van der

2005-01-01

We describe a route toward contactless imaging of arterial oxygen saturation (SpO2) distribution within tissue, based upon detection of a two-dimensional matrix of spatially resolved optical plethysmographic signals at different wavelengths. As a first step toward SpO 2-imaging we built a monochrome

Converting a fluorescence spectrophotometer into a three-channel colorimeter for color vision research

International Nuclear Information System (INIS)

Pardo, P.J.; Perez, A.L.; Suero, M.I.

2004-01-01

An old fluorescence spectrophotometer was recycled to make a three-channel colorimeter. The various modifications involved in its design and implementation are described. An optical system was added that allows the fusion of two visual stimuli coming from the two monochromators of the spectrofluorimeter. Each of these stimuli has a wavelength and bandwidth control, and a third visual stimulus may be taken from a monochromator, a cathode ray tube, a thin film transistor screen, or any other light source. This freedom in the choice of source of the third chromatic channel, together with the characteristics of the visual stimuli from the spectrofluorimeter, give this design a great versatility in its application to novel visual experiments on color vision

Converting a fluorescence spectrophotometer into a three-channel colorimeter for color vision research

Science.gov (United States)

Pardo, P. J.; Pérez, A. L.; Suero, M. I.

2004-01-01

An old fluorescence spectrophotometer was recycled to make a three-channel colorimeter. The various modifications involved in its design and implementation are described. An optical system was added that allows the fusion of two visual stimuli coming from the two monochromators of the spectrofluorimeter. Each of these stimuli has a wavelength and bandwidth control, and a third visual stimulus may be taken from a monochromator, a cathode ray tube, a thin film transistor screen, or any other light source. This freedom in the choice of source of the third chromatic channel, together with the characteristics of the visual stimuli from the spectrofluorimeter, give this design a great versatility in its application to novel visual experiments on color vision.

Measurement of X-ray beam emittance using crystal optics at an X-ray undulator beamline

CERN Document Server

Kohmura, Y; Awaji, M; Tanaka, T; Hara, T; Goto, S; Ishikawa, T

2000-01-01

We present a method of using crystal optics to measure the emittance of the X-ray source. Two perfect crystals set in (++) configuration work as a high-resolution collimator. The phase-space diagram (i.e. beam cross-section and angular distribution) could be determined without any assumptions on the light source. When the measurement is done at short wavelength radiation from undulator, the electron beam emittance is larger than the diffraction limit of the X-rays. Therefore, the electron beam emittance could be estimated. The measurement was done with the hard X-rays of 18.5 and 55 keV from an undulator beamline, BL 47XU, of SPring-8. The horizontal emittance of the X-ray beam was estimated to be about 7.6 nmrad, close to the designed electron beam emittance of the storage ring (7 nmrad). Some portions of the instrumental functions, such as the scattering by filters and windows along the beamline and the slight bent of the crystal planes of the monochromator, could not be precisely evaluated, but an upper li...

Reliability and short-term intra-individual variability of telomere length measurement using monochrome multiplexing quantitative PCR.

Directory of Open Access Journals (Sweden)

Sangmi Kim

Full Text Available Studies examining the association between telomere length and cancer risk have often relied on measurement of telomere length from a single blood draw using a real-time PCR technique. We examined the reliability of telomere length measurement using sequential samples collected over a 9-month period.Relative telomere length in peripheral blood was estimated using a single tube monochrome multiplex quantitative PCR assay in blood DNA samples from 27 non-pregnant adult women (aged 35 to 74 years collected in 7 visits over a 9-month period. A linear mixed model was used to estimate the components of variance for telomere length measurements attributed to variation among women and variation between time points within women. Mean telomere length measurement at any single visit was not significantly different from the average of 7 visits. Plates had a significant systematic influence on telomere length measurements, although measurements between different plates were highly correlated. After controlling for plate effects, 64% of the remaining variance was estimated to be accounted for by variance due to subject. Variance explained by time of visit within a subject was minor, contributing 5% of the remaining variance.Our data demonstrate good short-term reliability of telomere length measurement using blood from a single draw. However, the existence of technical variability, particularly plate effects, reinforces the need for technical replicates and balancing of case and control samples across plates.

Development and Application of Fiber-Optic Sensors in Environmental and Life Sciences

DEFF Research Database (Denmark)

Rickelt, Lars Fledelius

. A simple ratiometric intensity based O2 imaging protocol was developed using a conventional digital camera and the O2 distribution images were compared to life-time images obtained using a monochrome fast gate-able CCD camera. The method was applied to a biofilm growth incubator incubated with bacteria...

A Rapid and Convenient Procedure to Evaluate Optical Performance of Intraocular Lenses

Directory of Open Access Journals (Sweden)

Frank Schaeffel

2014-09-01

Full Text Available A new portable lens scanner was developed and tested for measuring focal lengths and relative contrast transfer of mono- and multifocal intraocular lenses (IOLs. A photograph of a natural scene was imaged in white light through an IOL in a water-filled cuvette, with their +21D base power largely neutralized by a −20D trial lens, using a USB monochrome video camera that could be focused via a laptop-controlled stepping motor from −8.5 to + 8.0D. The output of 10000 ON-OFF antagonistic “receptive fields” measuring the video image with adjustable diameter was continuously recorded by custom written software to quantify focus and relative contrast. Six monofocal and four multifocal IOLs, as well as two radial refractive gradient (RRG lenses were measured. After calibration with trial lenses the optical powers and relative contrast transfer of mono- and multifocal IOLs were readily measured. Refractive power profiles measured in RRG lenses closely matched data obtained from the manufacturer. The lens scanner uses a rapidly operating procedure, is portable and can be used to verify positions of the focal planes of mono- and multifocal IOLs in less than 3 s.

Determination of the resolution of the x-ray microscope XM-1 at beamline 6.1

Energy Technology Data Exchange (ETDEWEB)

Heck, J.M.; Meyer-Ilse, W.; Attwood, D.T. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

1997-04-01

Resolution determination in x-ray microscopy is a complex issue which depends on many factors. Many different criteria and experimental setups are used to characterize resolution. Some of the important factors affecting resolution include the partial coherence and spectrum of the illumination. The purpose of this research has been to measure the resolution of XM-1 at beamline 6.1 taking into account these factors, and to compare the measurements to theoretical calculations. The x-ray microscope XM-1, built by the Center for X-ray Optics (CXRO), has been operational since 1994 at the Advanced Light Source at E.O. Lawrence Berkeley National Laboratory. It is of the conventional (i.e. full-field) type, utilizing zone plate optics. ALS bending magnet radiation is focused by a condenser zone plate onto a monochromator pinhole immediately in front of the sample. X-rays transmitted through the sample are focused by a micro-zone plate onto a CCD camera. The pinhole and the condenser with a central stop constitute a linear monochromator. The spectral distribution of the light illuminating the sample has been calculated assuming geometrical optics.

Characteristics and performance of the Los Alamos VUV beamline at the NSLS

International Nuclear Information System (INIS)

Bartlett, R.J.; Trela, W.J.; Michaud, F.D.; Southworth, S.H.; Alkire, R.W.; Roy, P.; Rothe, R.; Walsh, P.J.; Shinn, N.

1988-01-01

We describe the design and performance of the Los Alamos VUV synchrotron radiation beamline, U3C, on the VUV ring of the National Synchrotron Light Source at Brookhaven National Laboratory. The beamline uses separate function optics to collect and focus the horizontally and vertically diverging beam. The monochromator is a grazing incidence Rowland circle instrument of the extended grasshopper design (ERG). A postmonochromator refocusing mirror is used to focus or collimate the diverging beam from the monochromator. The beamline control and diagnostics systems are also discussed. Particular emphasis in the design has been placed on the reduction of stray and harmonic light. Higher order light is reduced by a grazing angle mirror low pass filter installed immediately downstream from the monochromator while stray light is reduced through the use of baffles and thin film filters. Also included in the line is a differential pumping section that permits gas phase and other experiments requiring pressures in the 10 -5 to 10 -4 Torr range to be coupled to the beamline. (orig.)

Electro-Optical Characterization of Bistable Smectic A Liquid Crystal Displays

Science.gov (United States)

Buyuktanir, Ebru Aylin

My dissertation focuses the characterization and optimization of the electro-optical properties of smectic A (SmA) based liquid crystal (LC) displays. I present the development of robust and flexible bistable SmA LC displays utilizing polymer dispersed liquid crystal (PDLC) technology. The SmA PDLC displays produced on plastic substrates present electrically reversible memory, high contrast ratio, paper-like sunlight readability, and wide viewing angle characteristics. In order to optimize the SmA PDLC display, I investigated polymerization conditions, such as polymer concentration effect, polymerization temperature, and UV-light intensity variations. I characterized the electro-optical responses-such as static-response, time-response, threshold characteristics, and contrast ratio values' of the optimized SmA PDLC display and compared them to those of the pure SmA LC. The best electro-optical performance of SmA PDLC formulation was obtained using the combination of low mW/cm 2 and high mW/cm2 UV-light curing intensity. The contrast ratio of the optimum SmA PDLC at a 5o collection angle was 83% of that of the pure SmA material on plastic substrates. I fabricated 2.5 x 2.5 in., 4 x 4 in., and 6 x 6 in. sized monochrome flexible SmA PDLC displays, as well as red, yellow, and fluorescent dyes colored SmA PDLC displays on plastic substrates. The electro-optic performance of the bistable SmA LC display consisting of a patterned field-induced polymer wall infrastructure was also studied and compared to those of pure SmA material. I found that the contrast ratio of the SmA LC encapsulated between polymer walls was much greater than that of the SmA PDLC system, approaching the contrast ratio value of the pure SmA material. I also improved the electro-optical characteristics of bistable SmA LC displays by adding ferroparticles into the system. Finally, I illustrated the unique capabilities of polarized confocal Raman microscopy (CRM) to resolve the orientational order of Sm

Mirror boxes and mirror mounts for photophysics beamline

International Nuclear Information System (INIS)

Raja Rao, P.M.; Raja Sekhar, B.N.; Das, N.C.; Khan, H.A.; Bhattacharya, S.S.; Roy, A.P.

1996-01-01

Photophysics beamline makes use of one metre Seya-Namioka monochromator and two toroidal mirrors in its fore optics. The first toroidal mirror (pre mirror) focuses light originating from the tangent point of the storage ring onto the entrance slit of the monochromator and second toroidal mirror (post mirror) collects light from the exit slit of the monochromator and focuses light onto the sample placed at a distance of about one metre away from the 2nd mirror. To steer light through monochromator and to focus it on the sample of 1mm x 1mm size require precision rotational and translational motion of the mirrors and this has been achieved with the help of precision mirror mounts. Since Indus-1 operates at pressures less than 10 -9 m.bar, the mirror mounts should be manipulated under similar ultra high vacuum conditions. Considering these requirements, two mirror boxes and two mirror mounts have been designed and fabricated. The coarse movements to the mirrors are imparted from outside the mirror chamber with the help of x-y tables and precision movements to the mirrors are achieved with the help of mirror mounts. The UHV compatibility and performance of the mirror mounts connected to mirror boxes under ultra high vacuum condition is evaluated. The details of the design, fabrication and performance evaluation are discussed in this report. 5 refs., 9 figs., 1 tab

Highly transparent poly(2-ethyl-2-oxazoline)-TiO2 nanocomposite coatings for the conservation of matte painted artworks

OpenAIRE

Colombo, A.; Gherardi, Francesca; Goidanich, S.; Delaney, J. K.; de la Rie, E. R.; Ubaldi, M. C.; Toniolo, L.; Simonutti, R.

2015-01-01

A nanocomposite coating based on TiO2 nanoparticles and poly(2-ethyl-2-oxazoline) is used as consolidant of matte painted surfaces (temperas, watercolors, modern paintings). The aim of this work is to provide advances in the conservation of these works of art, while preserving their optical appearance, in terms of colour and gloss. Fiber Optic Reflectance Spectroscopy (FORS) measurements of a painting-model (an acrylic black monochrome) treated with the nanocomposite coatings revealed that it...

Distribution of Monochrome Screen Luminance in the CTOL Visual Technology Research Simulator.

Science.gov (United States)

1980-11-01

runway lines 3.8 4.2 8. Carrier runway 2.5 3.5 9. FLOLS* Meatball ** 2.0 2.4 10. FLOLS Background 0.68 1.3 *Fresnal Lens Optical Landing System...Standard U.S. Navy carrier optical landing device). ** Meatball is the light source of the FLOLS which the pilot uses for glideslope information in a carrier...LANDING DISPLAY FOV (Foot Lamberts) 1. Carrier Deck Runway Lighting 1.5 2. Carrier Runway Area 0.048 3. FLOLS Meatball 0.6 Figure 5 also shows the

Noite e dia e alguns monocromos psíquicos Night and day - and some psychical monochromes

Directory of Open Access Journals (Sweden)

Edson Luiz André de Sousa

2006-06-01

Full Text Available O artigo apresenta uma leitura do conto de Jack London "A sombra e o brilho" mostrando o funcionamento do princípio da mímesis no processo de identificação. Propõe-se a expressão monocromos psíquicos para esses espaços mentais de indiferenciação entre o eu e o Outro. Adota-se a tese de Caillois, que afirma que o eu é permeável ao espaço. Nessa perspectiva, o tema do duplo, amplamente desenvolvido por Freud, é fundamental. Partindo-se de notas sobre o trabalho do fotógrafo cego Bavcar, procura-se mostrar alguns traços da estrutura do olhar. O artigo finaliza mostrando as conexões possíveis dessas reflexões para a prática psicanalítica.The paper presents a reading of Jack London's tale "The Shadow and the brightness", showing how the principle of mimesis works in the process of the identification. We propose to call psychical monochromes the spaces of mental indifference between the self and the other. We follow the thesis of Roger Caillois: "the self is permeable in the space". In this perspective, the subject of the double, developped by Freud is essential. We try to show the dialectic of the structure of the look based in some notes about the work of the blind photographer Bavcar. The article finish with showing the possibles connections of all these points with the clinical work.

Plasma cleaning of beamline optical components: Contamination and gas composition effects

International Nuclear Information System (INIS)

Rosenberg, R.A.; Smith, J.A.; Wallace, D.J.

1992-01-01

We have initiated a program to study the impact of gas composition on the carbon removal rate during plasma cleaning of optical components, and of possible contamination due to the plasma processing. The measurements were performed in a test chamber designed to simulate the geometry of the grating/Codling mirror section of a Grasshopper monochromator. Removal rates were determined for a direct-current (dc) (Al electrode) discharge using a quartz crystal microbalance coated with polymethylmethacrylate, located at the position of the grating. Auger electron spectroscopy analysis of strateg- ically located, gold-coated stainless steel samples was employed to determine contamination. The relative removal rates of the gases studied were 3% C 2 F 6 /O 2 much-gt O 2 +H 2 O>O 2 ∼N 2 O>H 2 >N 2 . Although the C 2 F 6 /O 2 gas mixture showed a 20 times greater removal rate than its nearest competitor, it also caused significant contamination to occur. Contamination studies were performed for both dc and radio-frequency (rf) discharges. For the dc discharge we found that great care must be taken in order to avoid Al contamination; for the rf discharge, significant Fe contamination was observed

Inexpensive Raman Spectrometer for Undergraduate and Graduate Experiments and Research

Science.gov (United States)

Mohr, Christian; Spencer, Claire L.; Hippler, Michael

2010-01-01

We describe the construction and performance of an inexpensive modular Raman spectrometer that has been assembled in the framework of a fourth-year undergraduate project (costs below $5000). The spectrometer is based on a 4 mW 532 nm green laser pointer and a compact monochromator equipped with glass fiber optical connections, linear detector…

The Spectrophotometer II: A Module on the Spectral Properties of Light. Tech Physics Series.

Science.gov (United States)

Frank, Nathaniel; And Others

This module is designed to give the learner an understanding of the nature of light and how its properties are used in the design of spectrophotometers. Problems promote the use of spectrophotometers in qualitative analysis, the optical elements used in a monochromator, and the physical properties of the prism and the diffraction grating. Other…

Performance of the advanced cold neutron source and optics upgrades at the NIST Research Reactor

International Nuclear Information System (INIS)

Williams, R.E.; Kopetka, P.; Cook, J.C.; Rowe, J.M.

2003-01-01

On March 6, 2002, the NIST Research Reactor resumed routine operation following a six-month shutdown for facility upgrades and maintenance. During the shutdown, the original liquid hydrogen cold neutron source was removed, and the advanced cold source was installed. An optical filter was installed on one of the neutron guides, NG-3, replacing a crystal filter for the 30-m SANS instrument and the guide used between the chopper disks of the Disk Chopper time-of-flight Spectrometer (DCS) installed on NG-4 has been recently reconfigured. Additional improvements in the neutron optics of various instruments are being made. The advanced liquid hydrogen cold neutron source performs as expected, nearly doubling the flux available to most instruments. The measured gains range from about 1.4 at 2 A, to over a factor of two at 15 A. Also as expected, the heat load in the new source increased to 1200 watts, but the previously existing refrigerator has easily accommodated the increase. With intensity gains of a factor of two in the important long wavelength region of the spectrum, the advanced cold source significantly enhances the measurement capability of the cold neutron scattering instrumentation at NIST. The optical filter on NG-3 is also very successful; the 30-m SANS has an additional gain of two at 17 A. A system of refracting lenses and prisms near the SANS sample position has made possible measurements at low Q (0.0005 A -1 ) that were previously not feasible. The DCS has also seen additional intensity gain factors in excess of two for the majority of experiments and at short neutron wavelengths the gains exceed three. In addition, two new triple axis spectrometers will feature double-focusing monochromators in order to exploit the full size of the available thermal and cold neutron beam tubes. The success of the advanced cold source and enhanced neutron optics contributed to the recognition of the NIST Center for Neutron Research as 'the premiere neutron scattering

Construction and maintenance of SUNY facilities at the National Synchrotron Light Source. Progress report, 1 October 1981-1 July 1982

International Nuclear Information System (INIS)

Bigeleisen, J.

1982-01-01

Development of the SUNY beam line at the National Synchrotron Light Source is described. The line now includes monochromator/mirror optics with tandem arrangement of experiments. The beamline computer system is now working with CAMAC data acquisition, and a four-circle diffractometer, a small-angle-scattering bench, and a fluorescence EXAFS apparatus should be ready soon

Measurement of X-ray beam emittance using crystal optics at an X-ray undulator beamline

International Nuclear Information System (INIS)

Kohmura, Yoshiki; Suzuki, Yoshio; Awaji, Mitsuhiro; Tanaka, Takashi; Hara, Toru; Goto, Shunji; Ishikawa, Tetsuya

2000-01-01

We present a method of using crystal optics to measure the emittance of the X-ray source. Two perfect crystals set in (++) configuration work as a high-resolution collimator. The phase-space diagram (i.e. beam cross-section and angular distribution) could be determined without any assumptions on the light source. When the measurement is done at short wavelength radiation from undulator, the electron beam emittance is larger than the diffraction limit of the X-rays. Therefore, the electron beam emittance could be estimated. The measurement was done with the hard X-rays of 18.5 and 55 keV from an undulator beamline, BL 47XU, of SPring-8. The horizontal emittance of the X-ray beam was estimated to be about 7.6 nmrad, close to the designed electron beam emittance of the storage ring (7 nmrad). Some portions of the instrumental functions, such as the scattering by filters and windows along the beamline and the slight bent of the crystal planes of the monochromator, could not be precisely evaluated, but an upper limit for the vertical emittance of the electron beam could be obtained as 0.14 nmrad

Luminescent zinc(ii) and copper(i) complexes for high-performance solution-processed monochromic and white organic light-emitting devices.

Science.gov (United States)

Cheng, Gang; So, Gary Kwok-Ming; To, Wai-Pong; Chen, Yong; Kwok, Chi-Chung; Ma, Chensheng; Guan, Xiangguo; Chang, Xiaoyong; Kwok, Wai-Ming; Che, Chi-Ming

2015-08-01

The synthesis and spectroscopic properties of luminescent tetranuclear zinc(ii) complexes of substituted 7-azaindoles and a series of luminescent copper(i) complexes containing 7,8-bis(diphenylphosphino)-7,8-dicarba- nido -undecaborate ligand are described. These complexes are stable towards air and moisture. Thin film samples of the luminescent copper(i) complexes in 2,6-dicarbazolo-1,5-pyridine and zinc(ii) complexes in poly(methyl methacrylate) showed emission quantum yields of up to 0.60 (for Cu-3 ) and 0.96 (for Zn-1 ), respectively. Their photophysical properties were examined by ultrafast time-resolved emission spectroscopy, temperature dependent emission lifetime measurements and density functional theory calculations. Monochromic blue and orange solution-processed OLEDs with these Zn(ii) and Cu(i) complexes as light-emitting dopants have been fabricated, respectively. Maximum external quantum efficiency (EQE) of 5.55% and Commission Internationale de l'Eclairage (CIE) coordinates of (0.16, 0.19) were accomplished with the optimized Zn-1 -OLED while these values were, respectively 15.64% and (0.48, 0.51) for the optimized Cu-3 -OLED. Solution-processed white OLEDs having maximum EQE of 6.88%, CIE coordinates of (0.42, 0.44), and colour rendering index of 81 were fabricated by using these luminescent Zn(ii) and Cu(i) complexes as blue and orange light-emitting dopant materials, respectively.

Calibration of hard x-ray (15 - 50 keV) optics at the MPE test facility PANTER

Science.gov (United States)

Bräuninger, Heinrich; Burkert, Wolfgang; Hartner, Gisela D.; Citterio, Oberto; Ghigo, Mauro; Mazzoleni, Francesco; Pareschi, Giovanni; Spiga, Daniele

2004-02-01

The Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany, operates the large X-ray beam line facility PANTER for testing astronomical systems. At PANTER a number of telescopes like EXOSAT, ROSAT, SAX, JET-X, ABRIXAS, XMM and SWIFT operating in the soft energy range (0.02 - 15 keV) have been successfully calibrated. In the present paper we report on an important upgrade recently implemented that enables the calibration of hard X-ray optics (from 15 up to 50 keV). Currently hard X-ray optics based on single and multilayer coating are being developed for several future X-ray missions. The hard X-ray calibrations at PANTER are carried out by a high energy source based on an electron gun and several anodes, able to cover the energy range from 4.5 up to 50 keV. It provides fluxes up to 104 counts/sec/cm2 at the instrument chamber with a stability better than 1%. As detector a pn-CCD camera operating between 0.2 and 50 keV and a collecting area of 36 cm2 is used. Taking into account the high energy resolution of the CCD (145 eV at 6 keV), a very easy way to operate the facility in hard X-ray is in energy-dispersive mode (i.e. with a broad-band beam). A double crystal monochromator is also available providing energies up to 20 keV. In this paper we present the first results obtained by using PANTER for hard X-ray characterizations, performed on prototype multilayer optics developed by the Osservatorio Astronomico di Brera (OAB), Milano, Italy, and the Harvard-Smithsonian Center for Astrophysics (CfA), Cambridge, MA, USA.

MC ray-tracing optimization of lobster-eye focusing devices with RESTRAX

International Nuclear Information System (INIS)

Saroun, Jan; Kulda, Jiri

2006-01-01

The enhanced functionalities of the latest version of the RESTRAX software, providing a high-speed Monte Carlo (MC) ray-tracing code to represent a virtual three-axis neutron spectrometer, include representation of parabolic and elliptic guide profiles and facilities for numerical optimization of parameter values, characterizing the instrument components. As examples, we present simulations of a doubly focusing monochromator in combination with cold neutron guides and lobster-eye supermirror devices, concentrating a monochromatic beam to small sample volumes. A Levenberg-Marquardt minimization algorithm is used to optimize simultaneously several parameters of the monochromator and lobster-eye guides. We compare the performance of optimized configurations in terms of monochromatic neutron flux and energy spread and demonstrate the effect of lobster-eye optics on beam transformations in real and momentum subspaces

Compact and Light-Weight Solar Spaceflight Instrument Designs Utilizing Newly Developed Miniature Free-Standing Zone Plates: EUV Radiometer and Limb-Scanning Monochromator

Science.gov (United States)

Seely, J. F.; McMullin, D. R.; Bremer, J.; Chang, C.; Sakdinawat, A.; Jones, A. R.; Vest, R.

2014-12-01

Two solar instrument designs are presented that utilize newly developed miniature free-standing zone plates having interconnected Au opaque bars and no support membrane resulting in excellent long-term stability in space. Both instruments are based on a zone plate having 4 mm outer diameter and 1 to 2 degree field of view. The zone plate collects EUV radiation and focuses a narrow bandpass through a pinhole aperture and onto a silicon photodiode detector. As a miniature radiometer, EUV irradiance is accurately determined from the zone plate efficiency and the photodiode responsivity that are calibrated at the NIST SURF synchrotron facility. The EUV radiometer is pointed to the Sun and measures the absolute solar EUV irradiance in high time cadence suitable for solar physics and space weather applications. As a limb-scanning instrument in low earth orbit, a miniature zone-plate monochromator measures the extinction of solar EUV radiation by scattering through the upper atmosphere which is a measure of the variability of the ionosphere. Both instruments are compact and light-weight and are attractive for CubeSats and other missions where resources are extremely limited.

Extension of self-seeding scheme with single crystal monochromator to lower energy <5 keV as a way to generate multi-TW scale pulses at the European XFEL

Energy Technology Data Exchange (ETDEWEB)

Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2012-07-15

We propose a use of the self-seeding scheme with single crystal monochromator to produce high power, fully-coherent pulses for applications at a dedicated bio-imaging beamline at the European X-ray FEL in the photon energy range between 3.5 keV and 5 keV. We exploit the C(111) Bragg reflection ({pi}-polarization) in diamond crystals with a thickness of 0.1 mm, and we show that, by tapering the 40 cells of the SASE3 type undulator the FEL power can reach up to 2 TW in the entire photon energy range. The present design assumes the use of a nominal electron bunch with charge 0.1 nC at nominal electron beam energy 17.5 GeV. The main application of the scheme proposed in this work is for single shot imaging of individual protein molecules. (orig.)

Extension of self-seeding scheme with single crystal monochromator to lower energy <5 keV as a way to generate multi-TW scale pulses at the European XFEL

International Nuclear Information System (INIS)

Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

2012-07-01

We propose a use of the self-seeding scheme with single crystal monochromator to produce high power, fully-coherent pulses for applications at a dedicated bio-imaging beamline at the European X-ray FEL in the photon energy range between 3.5 keV and 5 keV. We exploit the C(111) Bragg reflection (π-polarization) in diamond crystals with a thickness of 0.1 mm, and we show that, by tapering the 40 cells of the SASE3 type undulator the FEL power can reach up to 2 TW in the entire photon energy range. The present design assumes the use of a nominal electron bunch with charge 0.1 nC at nominal electron beam energy 17.5 GeV. The main application of the scheme proposed in this work is for single shot imaging of individual protein molecules. (orig.)

Comparison of TXRF detection limits for low Z elements in different beam geometries at the PTB monochromator beamline for undulator radiation at Bessy II

International Nuclear Information System (INIS)

Beckhoff, B.; Ulm, G.; Pepponi, G.; Streli, C.; Wobrauschek, P.; Fabry, L.; Pahlke, S.

2000-01-01

A set of initial TXRF experiments were conducted at the PTB plane grating monochromator beamline for undulator radiation at the electron storage ring BESSY II allowing for exciting energies between 0.1 keV and 1.9 keV. Here, the lower limits of detection of TXRF analysis investigated for some low Z elements such as C, N, 0, Al, Mg and Na in two different detection geometries for various excitation modes. Compared to ordinary XRF geometries involving large incident angles, the TXRF variant offers also at low excitation energies drastically reduced background contributions due to the small penetration depth caused by the total reflection of the incident beam at the polished surface of a flat specimen carrier such as a silicon wafer. For the sake of an application-oriented TXRF approach, droplet samples on Si wafer surfaces were prepared by Wacker Siltronic and investigated in the TXRF irradiation chamber of the Atominstitut offering a semiconductor detector with a thin entrance window that was only 300 nm thick. (author)

An improved microstrip plasma for optical emission spectrometry of gaseous species

Energy Technology Data Exchange (ETDEWEB)

Schermer, Susanne; Bings, Nicolas H.; Bilgic, Attila M.; Stonies, Robert; Voges, Edgar; Broekaert, Jose A.C. E-mail: jose.broekaert@chemie.uni-hamburg.de

2003-09-26

A modified compact 2.45 GHz microstrip plasma (MSP) operated with Ar as working gas at atmospheric pressure has been characterized and examined for its suitability for the determination of Hg as gaseous species by optical emission spectrometry. As a formerly described MSP the new device is provided on a sapphire substrate. The areas of plasma stability in terms of gas flow rates and microwave power for both MSPs with respect to plasma form and reflected power were investigated. Power levels of 5-40 W and Ar flow rates of 15-60 l/h were used. The modified MSP, which extends out of the channel in the sapphire substrate, was used for the recording of emission spectra for Hg vapor at different working conditions. Using optimized parameters a detection limit for Hg of less than 10 ng Hg/l Ar is obtained. The attainable excitation temperatures in the modified MSP at different microwave power were determined under the use of Fe as thermometric species and introducing ferrocene into the plasma. They were found to be at the order of 6000-7000 K for a power of 10-40 W and a gas flow of 15 l/h. It was shown that the modified MSP source can be combined with both a conventional monochromator with photomultiplier detection and a miniaturized spectrometer with CCD detection, whereby space-angle limitations are not stringent.

Biological monochromator with a high flux in the visible spectrum; Un monochromateur biologique a haut flux dans le visible

Energy Technology Data Exchange (ETDEWEB)

Andre, M; Guerin de Montgareuil, P [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

1965-07-01

The object is to carry out research into photosynthesis using energetic illuminations similar to those employed with white light studies. The limitations are due mainly to the source. A comparison of various possible solutions has led to the choice of the sun used in conjunction with 4 large gratings. In an intermediate stage, a description is given of a medium-aperture monochromator with a 3 kW xenon arc and a single grating. With this set-up it is possible to obtain the following performance, given as an example; energy illumination, 1.3 mW/cm{sup 2} over a surface of 50 cm{sup 2} and for a bandwidth at half-height of 50 Angstroms. (authors) [French] L'objectif est de poursuivre en lumiere monochromatique des etudes de photosynthese avec des eclairements energetiques analogues a ceux qu'on utilise en lumiere blanche. Les limitations se situent principalement au niveau de la source. Une comparaison effectuee entre differentes solutions possibles conduit a preconiser l'emploi du soleil associe a 4 grands reseaux. En etape intermediaire on decrit un monochromateur de moyenne ouverture, avec un arc au xenon de 3 kW et un seul reseau, qui permet d'atteindre les performances suivantes donnees a titre d'exemple: eclairement energetique de 1,3 mW/cm{sup 2} sur une surface de 50 cm{sup 2} et pour une bande passante a mi-hauteur de 50 Angstroems. (auteurs)

Varied line-space gratings: past, present and future

International Nuclear Information System (INIS)

Hettrick, M.C.

1985-08-01

A classically ruled diffraction grating consists of grooves which are equidistant, straight and parallel. Conversely, the so-called ''holographic'' grating (formed by the interfering waves of coherent visible light), although severely constrained by the recording wavelength and recording geometry, has grooves which are typically neither equidistant, straight nor parallel. In contrast, a varied line-space (VLS) grating, in common nomenclature, is a design in which the groove positions are relatively unconstrained yet possess sufficient symmetry to permit mechanical ruling. Such seemingly exotic gratings are no longer only a theoretical curiosity, but have been ruled and used in a wide variety of applications. These include: (1) aberration-corrected normal incidence concave gratings for Seya-Namioka monochromators and optical de-multiplexers, (2) flat-field grazing incidence concave gratings for plasma diagnostics, (3) aberration-corrected grazing incidence plane gratings for space-borne spectrometers, (4) focusing grazing incidence plane grating for synchrotron radiation monochromators, and (5) wavefront generators for visible interferometry of optical surfaces (particularly aspheres). Future prospects of VLS gratings as dispersing elements, wavefront correctors and beamsplitters appear promising. The author discusses the history of VLS gratings, their present applications, and their potential in the future. 61 refs., 24 figs

High-brightness beamline for x-ray spectroscopy at the ALS

Energy Technology Data Exchange (ETDEWEB)

Perera, R.C.C.; Jones, G. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States); Lindle, D.W. [Univ. of Nevada, Las Vegas, NV (United States)

1997-04-01

Beamline 9.3.1 at the Advanced Light Source (ALS) is a windowless beamline, covering the 1-6 keV photon-energy range, designed to achieve the goals of high energy resolution, high flux, and high brightness at the sample. When completed later this year, it will be the first ALS monochromatic hard x-ray beamline, and its brightness will be an order of magnitude higher than presently available in this energy range. In addition, it will provide flux and resolution comparable to any other beamline now in operation. To achieve these goals, two technical improvements, relative to existing x-ray beamlines, were incorporated. First, a somewhat novel optical design for x-rays, in which matched toroidal mirrors are positioned before and after the double-crystal monochromator, was adopted. This configuration allows for high resolution by passing a collimated beam through the monochromator, and for high brightness by focusing the ALS source on the sample with unit magnification. Second, a new {open_quotes}Cowan type{close_quotes} double-crystal monochromator based on the design used at NSLS beamline X-24A was developed. The measured mechanical precision of this new monochromator shows significant improvement over existing designs, without using positional feedback available with piezoelectric devices. Such precision is essential because of the high brightness of the radiation and the long distance (12 m) from the source (sample) to the collimating (focusing) mirror. This combination of features will provide a bright, high resolution, and stable x-ray beam for use in the x-ray spectroscopy program at the ALS.

X-ray absorption spectroscopy of diluted system by undulator photon source and multi-element solid-state detector

CERN Document Server

Tanida, H

2001-01-01

In order to measure the extended X-ray absorption fine structure (EXAFS) spectrum of an ultra-diluted system, an optics and detector control system for a synchrotron radiation beamline is developed. The undulator gap width is continuously tuned to obtain the maximum X-ray photon flux during the energy scan for the EXAFS measurement. A piezoelectric translator optimizes the parallelism of the double crystal in a monochromator at each measurement point to compensate for mechanical errors of the monochromator, resulting in a smooth and intense X-ray photon flux during the measurement. For a detection of a weak fluorescence signal from diluted samples, a 19-element solid-state detector and digital signal processor are used. A K-edge EXAFS spectrum of iron in a myoglobin aqueous solution with a concentration of 5.58 parts per million was obtained by this system.

Monochromatization of synchrotron radiation for studies in photoelectron spectroscopy

International Nuclear Information System (INIS)

Murty, P.S.

1981-01-01

Synchrotron radiation provides a tunable photon source which bridges the wavelength gap between HeI and AlKsub(α) radiation sources in photoelectron spectroscopy. The essential component for using synchrotron radiation is a monochromator. Some design features of the monochromators fabricated at Stanford, U.S.A., and Orsay, France, are described. The Stanford monochromator is a silicon crystal monochromator yielding 8 keV X-ray beam and is used with SPEAR storage ring facility, while the Orsay monochromator is a grazing incidence grating monochromator used for UPS studies. (M.G.B.)

Infrared (IR) photon-sensitive spectromicroscopy in a cryogenic environment

Science.gov (United States)

Pereverzev, Sergey

2016-06-14

A system designed to suppress thermal radiation background and to allow IR single-photon sensitive spectromicroscopy of small samples by using both absorption, reflection, and emission/luminescence measurements. The system in one embodiment includes: a light source; a plurality of cold mirrors configured to direct light along a beam path; a cold or warm sample holder in the beam path; windows of sample holder (or whole sample holder) are transparent in a spectral region of interest, so they do not emit thermal radiation in the same spectral region of interest; a cold monochromator or other cold spectral device configured to direct a selected fraction of light onto a cold detector; a system of cold apertures and shields positioned along the beam path to prevent unwanted thermal radiation from arriving at the cold monochromator and/or the detector; a plurality of optical, IR and microwave filters positioned along the beam path and configured to adjust a spectral composition of light incident upon the sample under investigation and/or on the detector; a refrigerator configured to maintain the detector at a temperature below 1.0K; and an enclosure configured to: thermally insulate the light source, the plurality of mirrors, the sample holder, the cold monochromator and the refrigerator.

Development of a low-cost, 11 µm spectral domain optical coherence tomography surface profilometry prototype

Science.gov (United States)

Suliali, Nyasha J.; Baricholo, Peter; Neethling, Pieter H.; Rohwer, Erich G.

2017-06-01

A spectral-domain Optical Coherence Tomography (OCT) surface profilometry prototype has been developed for the purpose of surface metrology of optical elements. The prototype consists of a light source, spectral interferometer, sample fixture and software currently running on Microsoft® Windows platforms. In this system, a broadband light emitting diode beam is focused into a Michelson interferometer with a plane mirror as its sample fixture. At the interferometer output, spectral interferograms of broadband sources were measured using a Czerny-Turner mount monochromator with a 2048-element complementary metal oxide semiconductor linear array as the detector. The software performs importation and interpolation of interferometer spectra to pre-condition the data for image computation. One dimensional axial OCT images were computed by Fourier transformation of the measured spectra. A first reflection surface profilometry (FRSP) algorithm was then formulated to perform imaging of step-function-surfaced samples. The algorithm re-constructs two dimensional colour-scaled slice images by concatenation of 21 and 13 axial scans to form a 10 mm and 3.0 mm slice respectively. Measured spectral interferograms, computed interference fringe signals and depth reflectivity profiles were comparable to simulations and correlated to displacements of a single reflector linearly translated about the arm null-mismatch point. Surface profile images of a double-step-function-surfaced sample, embedded with inclination and crack detail were plotted with an axial resolution of 11 μm. The surface shape, defects and misalignment relative to the incident beam were detected to the order of a micron, confirming high resolution of the developed system as compared to electro-mechanical surface profilometry techniques.

Thin Films for X-ray Optics

Science.gov (United States)

Conley, Raymond

Focusing x-rays with refraction requires an entire array of lens instead of a single element, each contributing a minute amount of focusing to the system. In contrast to their visible light counterparts, diffractive optics require a certain depth along the optical axis in order to provide sufficient phase shift. Mirrors reflect only at very shallow angles. In order to increase the angle of incidence, contribution from constructive interference within many layers needs to be collected. This requires a multilayer coating. Thin films have become a central ingredient for many x-ray optics due to the ease of which material composition and thickness can be controlled. Chapter 1 starts with a short introduction and survey of the field of x-ray optics. This begins with an explanation of reflective multilayers. Focusing optics are presented next, including mirrors, zone plates, refractive lenses, and multilayer Laue lens (MLL). The strengths and weaknesses of each "species" of optic are briefly discussed, alongside fabrication issues and the ultimate performance for each. Practical considerations on the use of thin-films for x-ray optics fabrication span a wide array of topics including material systems selection and instrumentation design. Sputter deposition is utilized exclusively for the work included herein because this method of thin-film deposition allows a wide array of deposition parameters to be controlled. This chapter also includes a short description of two deposition systems I have designed. Chapter 2 covers a small sampling of some of my work on reflective multilayers, and outlines two of the deposition systems I have designed and built at the Advanced Photon Source. A three-stripe double multilayer monochromator is presented as a case study in order to detail specifications, fabrication, and performance of this prolific breed of x-ray optics. The APS Rotary Deposition System was the first deposition system in the world designed specifically for multilayer

Optics/Optical Diagnostics Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Optics/Optical Diagnostics Laboratory supports graduate instruction in optics, optical and laser diagnostics and electro-optics. The optics laboratory provides...

Novel emission phenomena in organic microcavities (Conference Presentation)

Science.gov (United States)

Leo, Karl

2016-09-01

Organic light emitting diodes (OLED) are today a mature techology and have reached high efficiency both in monochrome and white devices. One of the main research areas for further improvement is still the optical design which enables many new approaches to enhance efficiency and realize special emission properties. In this talk, I will review our recent work on OLED outcoupling, in particular for devices encapsulated in microcavities and patterned structures.

Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

Energy Technology Data Exchange (ETDEWEB)

Tirsell, K.G.; Berglin, E.J.; Fuchs, B.A.; Holdener, F.R.; Humpal, H.H.; Karpenko, V.P.; Kulkarni, S.; Fantone, S.D.

1987-08-01

New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the entrance slit plane appears very good. In this paper we discuss considerations leading to the choice of SiC for each of the two first mirrors. We present highlights of the development of these mirrors with some emphasis on SiC polishing techniques. In addition, the specialized metrology developed to produce the more difficult figure of the toroid will be described. Measured surface roughness and figure results will be presented. 19 refs., 11 figs.

Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

International Nuclear Information System (INIS)

Tirsell, K.G.; Berglin, E.J.; Fuchs, B.A.; Holdener, F.R.; Humpal, H.H.; Karpenko, V.P.; Kulkarni, S.; Fantone, S.D.

1987-08-01

New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the entrance slit plane appears very good. In this paper we discuss considerations leading to the choice of SiC for each of the two first mirrors. We present highlights of the development of these mirrors with some emphasis on SiC polishing techniques. In addition, the specialized metrology developed to produce the more difficult figure of the toroid will be described. Measured surface roughness and figure results will be presented. 19 refs., 11 figs

Calibration and standards beamline 6.3.2 at the Advanced Light Source

International Nuclear Information System (INIS)

Underwood, J.H.; Gullikson, E.M.; Koike, M.; Batson, P.J.; Denham, P.E.; Franck, K.D.; Tackaberry, R.E.; Steele, W.F.

1996-01-01

This bending magnet beamline has been in operation since February 1995 for the characterization of optical elements (mirrors, gratings, multilayers, detectors, etc.) in the energy range 50 endash 1000 eV. Although it was designed primarily for precision reflectometry of multilayer reflecting optics for EUV projection lithography, it has capabilities for a wide range of measurements. The optics consist of a monochromator, a reflectometer, and refocusing mirrors to provide a small spot on the sample. The monochromator is a very compact, entrance-slitless, varied-line-spacing plane-grating design in which the mechanically ruled grating operates in the converging light from a spherical mirror working at high demagnification. Aberrations of the mirror are corrected by the line spacing variation, so that the spectral resolving power λ/Δλ is limited by the ALS source size to about 7000. Wavelength is scanned by simple rotation of the grating with a fixed exit slit. The reflectometer has the capability of positioning the sample to within 10 μm and setting its angular position to 0.002 degree. LABVIEW TM based software provides a convenient interface to the user. The reflectometer is separated from the beamline by a differential pump and can be pumped down in 1/2 hour. Auxiliary experimental stations can be mounted behind the reflectometer. Results are shown that demonstrate the performance and operational convenience of the beamline copyright 1996 American Institute of Physics

Optimum plastic scintillator and optical fiber combination for brachytherapy dosimetry

International Nuclear Information System (INIS)

Arnfield, Mark R.; Gaballa, Hani E.; Zwicker, Robert D.; Islam, Quazi; Schmidt-Ullrich, Rupert

1995-01-01

Purpose/Objective: There have been several recent reports using plastic scintillators to measure dose in photon and electron beams. External beam measurements agreed well with standard ion chamber dosimetry. This was implemented by using two identical, parallel optical fibers with a small piece of plastic scintillator attached to one. We have constructed a similar device for application to brachytherapy. Brachytherapy dosimetry is a more difficult problem than external beam because of high dose gradients and widely ranging photon energies. Based on detailed spectral measurements, we have designed a dosimeter specifically to meet the unique, stringent needs of brachytherapy. Materials and Methods: The work consisted of two stages. In the first stage, we measured the optical spectra emitted by commercial plastic scintillators and silica core optical fibers in the presence of a 10 Curie iridium 192 HDR source. In the second stage, the spectral information was used to select an optimum combination of scintillator and fiber which were incorporated in the dosimeter. Equipment for the spectral measurements included a 0.1 meter monochromator with a sensitive photomultiplier (PMT) with flat response across the visible. The resolution of spectral scans was 4 nm. The dosimeter was constructed with a 1mm x 3mm piece of plastic scintillator bonded with optical cement to a 0.6 mm diameter silica core optical fiber. A second, identical optical fiber running alongside the first, with no scintillator attached, was used for background subtraction. Two PMTs with high sensitivity in the visible were used at the fiber distal ends. There was a space for an optical filter between the fiber and the PMTs, whose purpose is described below. The PMTs were connected to a differential pair whose output was transferred to a current source for measurement by a standard electrometer. Results: The scintillation spectra of six different types of silica core optical fibers in the presence of the

New organic materials for optics: optical storage and nonlinear optics

International Nuclear Information System (INIS)

Gan, F.

1996-01-01

New organic materials have received considerable attention recently, due to their easy preparation and different variety. The most application fields in optics are optical storage and nonlinear optics. In optical storage the organic dyes have been used for example, in record able and erasable compact disks (CD-R, CD-E) nonlinear optical effects, such as nonlinear optical absorption, second and third order optical absorption, second and third order optical nonlinearities, can be applied for making optical limiters, optical modulators, as well as laser second and third harmonic generations. Due to high value of optical absorption and optical nonlinearity organic materials are always used as thin films in optical integration. In this paper the new experimental results have been presented, and future development has been also discussed. (author)

Earth, soil and environmental science research facility at sector 13 of the Advanced Photon Source. I. Sector layout and optical design

Energy Technology Data Exchange (ETDEWEB)

Eng, P.; Jaski, Y.R.; Lazarz, N.; Murray, P.; Pluth, J.; Rarback, H.; Rivers, M.; Sutton, S. [CARS, University of Chicago, 5640 S. Ellis Avenue, Chicago, IL (United States)

1996-09-01

The earth, soil and environmental science component (GSECARS) of the Consortium of Advanced Radiation Sources (CARS), is designing a national research facility to be built at sector 13 of the Advanced Photon Source. The bending magnet beam will be split to allow simultaneous operation of two stations, a monochromatic (8{endash}15 keV) side station and a multipurpose, white beam/monochromatic end station. The undulator beamline will have two white beam stations, which may operate simultaneously using a double-crystal monochromator (cryogenic Si) with a thin first crystal. In this mode, the upstream station will accept the monochromatized (4.5{endash}22 keV) beam deflected horizontally by a third (bendable) Ge crystal, while the end station accepts the high energy component (blue beam) transmitted by the first crystal. The need for small x-ray beams and broad spectral range have led us to base the focusing aspects of the optic design on grazing incidence mirrors. Both our bending magnet and insertion device beamlines will have long ({approximately}1 m), bendable mirrors (demagnification {lt}11, E(cut-off) {approx_gt}70 keV; beam sizes {approx_gt}tens of micrometers). For smaller focal spots, we will use small, dynamically bent Kirpatrick-Baez mirrors (demagnification 100{endash}400; E(cut-off) {lt}70 keV; beam sizes {approximately}1 micrometer). A unique aspect of our insertion device beamline is the ability to deliver focused white beam to the sample, through the incorporation of a power management pinhole in the first optics enclosure. {copyright} {ital 1996 American Institute of Physics.}

Construction and performance of BL28 of the Photon Factory for circularly polarized synchrotron radiation

International Nuclear Information System (INIS)

Kagoshima, Y.; Muto, S.; Miyahara, T.; Koide, T.; Yamamoto, S.; Kitamura, H.

1992-01-01

A branch beamline, BL28A, has been constructed for the application of circularly polarized vacuum ultraviolet radiation. The radiation can be obtained in the helical undulator operation mode of an insertion device, EMPW number-sign 28, which is also cut for elliptically polarized hard x-ray radiation. T first harmonic of the helical undulator radiation can be tuned from 40 to 350 eV with its corresponding K value from 3 to 0.2. A monochromator working basically with constant deviation optics was installed, and has started its operation. A circularly polarized flux of ∼10 10 photons/s has been achieved with energy resolution of around 500--1000 at the first harmonic peak. The circular polarization after the monochromator was estimated to be higher than 70% by comparing theory and experiment on the magnetic circular dichroism of nickel films in the 3p-3d excitation region. The design philosophy of the beamline and recent results on the performance tests are presented

Construction and performance of BL28 of the Photon Factory for circularly polarized synchrotron radiation

Science.gov (United States)

Kagoshima, Yasushi; Muto, Sadatsugu; Miyahara, Tsuneaki; Koide, Tsuneharu; Yamamoto, Shigeru; Kitamura, Hideo

1992-01-01

A branch beamline, BL28A, has been constructed for the application of circularly polarized vacuum ultraviolet radiation. The radiation can be obtained in the helical undulator operation mode of an insertion device, EMPW♯28, which is also cut for elliptically polarized hard x-ray radiation. T first harmonic of the helical undulator radiation can be tuned from 40 to 350 eV with its corresponding K value from 3 to 0.2. A monochromator working basically with constant deviation optics was installed, and has started its operation. A circularly polarized flux of ˜1010 photons/s has been achieved with energy resolution of around 500-1000 at the first harmonic peak. The circular polarization after the monochromator was estimated to be higher than 70% by comparing theory and experiment on the magnetic circular dichroism of nickel films in the 3p-3d excitation region. The design philosophy of the beamline and recent results on the performance tests are presented.

Soft optics in intelligent optical networks

Science.gov (United States)

Shue, Chikong; Cao, Yang

2001-10-01

In addition to the recent advances in Hard-optics that pushes the optical transmission speed, distance, wave density and optical switching capacity, Soft-optics provides the necessary intelligence and control software that reduces operational costs, increase efficiency, and enhances revenue generating services by automating optimal optical circuit placement and restoration, and enabling value-added new services like Optical VPN. This paper describes the advances in 1) Overall Hard-optics and Soft-optics 2) Layered hierarchy of Soft-optics 3) Component of Soft-optics, including hard-optics drivers, Management Soft-optics, Routing Soft-optics and System Soft-optics 4) Key component of Routing and System Soft-optics, namely optical routing and signaling (including UNI/NNI and GMPLS signaling). In summary, the soft-optics on a new generation of OXC's enables Intelligent Optical Networks to provide just-in-time service delivery and fast restoration, and real-time capacity management that eliminates stranded bandwidth. It reduces operational costs and provides new revenue opportunities.

Variable-metric diffraction crystals for x-ray optics

International Nuclear Information System (INIS)

Smither, R.K.; Fernandez, P.B.

1992-01-01

A variable-metric (VM) crystal is one in which the spacing between the crystalline planes changes with position in the crystal. This variation can be either parallel to the crystalline planes or perpendicular to the crystalline planes of interest and can be produced by either introducing a thermal gradient in the crystal or by growing a crystal made of two or more elements and changing the relative percentages of the two elements as the crystal is grown. A series of experiments were performed in the laboratory to demonstrate the principle of the variable-metric crystal and its potential use in synchrotron beam lines. One of the most useful applications of the VM crystal is to increase the number of photons per unit bandwidth in a diffracted beam without losing any of the overall intensity. In a normal synchrotron beam line that uses a two-crystal monochromator, the bandwidth of the diffracted photon beam is determined by the vertical opening angle of the beam which is typically 0.10--0.30 mrad or 20--60 arcsec. When the VM crystal approach is applied, the bandwidth of the beam can be made as narrow as the rocking curve of the diffracting crystal, which is typically 0.005--0.050 mrad or 1--10 arcsec. Thus a very large increase of photons per unit bandwidth (or per unit energy) can be achieved through the use of VM crystals. When the VM principle is used with bent crystals, new kinds of x-ray optical elements can be generated that can focus and defocus x-ray beams much like simple lenses where the focal length of the lens can be changed to match its application. Thus both large magnifications and large demagnifications can be achieved as well as parallel beams with narrow bandwidths

Design and development of PEEM/ARPES beamline for Indus-2 synchrotron radiation source

International Nuclear Information System (INIS)

Goutam, U.K.; Sharma, R.K.; Jagannath; Gadkari, S.C.; Yakhmi, J.V.; Sahni, V.C.

2008-06-01

A high resolution beamline having two branches dedicated to Photo Emission Electron Microscopy (PEEM) and Angle Resolved Photo Electron Spectroscopy (ARPES) is planned for Indus-2 synchrotron radiation source. These two techniques open a wide field of new applications in materials research and have proven to be powerful tools to investigate topological, elemental, chemical state, electronic and magnetic properties of surfaces, thin films, and multilayers at high resolutions.The beamline will cover a large energy range from 10 to 4000 eV and is expected to deliver a flux of the order of ∼10 13 ph/s/0.1%B.W. with an energy resolution of ∼10 -4 . This report describes the optical design, beamline layout, effects of heat load on various components and the expected performance of the beamline. This beamline would have a collimating mirror for vertical collimation of the beam, plane grating/double crystal monochromator to make the white synchrotron beam monochromatic in entire energy range, toroidal mirror for splitting the beam as well as for intermediate focusing and a Kirkpatrick-Baez (K-B) mirror system for focusing the beam both in vertical and horizontal directions at the final sample location. Total beamline will be 36m long. Optical design has been carried out involving various computer codes such as XOP2.1, SHADOWVUI, SPECTRA 8.0 etc. Head load calculations have been performed using ANSYS, a finite element analysis code. Using this code, temperature distribution, thermal deformation and slope error values for collimating mirror, grating monochromator and double crystal monochromator using several possible cooling arrangements have been calculated and depending on these parameters, best options for different components have been selected for the beamline. Experimental stations of this beamline consist of ultra-high vacuum compatible chambers in which various probes, analyzers, detectors and other facilities are housed. A toroidal electron energy analyzer will

Repetitive display system of line profiles for Doppler broadening measurement

International Nuclear Information System (INIS)

Mohri, A.; Narihara, K.; Haba, K.

1982-10-01

Line profiles of impurities in visible and ultraviolet regions are repetitively displayed on a CRT with an interval of 250 mu s or 500 mu s, using a system composed of a Czerny-Turner monochromator with 1 m F.L., a self-resonant optical scanner, a photomultiplier shielded against hard X-rays and electronic circuits. The profile resolution is 0.035 nm FWHM. This system can be used in the environment of strong hard X-rays. (author)

X-ray monochromators for high-power synchrotron radiation sources

Science.gov (United States)

Hart, Michael

1990-11-01

Exact solutions to the problems of power flow from a line source of heat into a semicylinder and of uniform heat flow normal to a flat surface are discussed. These lead to bounds on feasible designs and the boundary layer problem can be placed in proper perspective. While finite element calculations are useful if the sample boundaries are predefined, they are much less help in establishing design principles. Previous work on hot beam X-ray crystal optics has emphasised the importance of coolant hydraulics and boundary layer heat transfer. Instead this paper emphasises the importance of the elastic response of crystals to thermal strainfields and the importance of maintaining the Darwin reflectivity. The conclusions of this design study are that the diffracting crystal region should be thin, but not very thin, similar in area to the hot beam footprint, part of a thin-walked buckling crystal box and remote from the support to which the crystal is rigidly clamped. Prototype 111 and 220 cooled silicon crystals tested at the National Synchrotron Light Source at Brookhaven have almost perfect rocking curves under a beam heat load of {1}/{3}kW.

Optical Communication over Plastic Optical Fibers Integrated Optical Receiver Technology

CERN Document Server

Atef, Mohamed

2013-01-01

This book presents high-performance data transmission over plastic optical fibers (POF) using integrated optical receivers having good properties with multilevel modulation, i.e. a higher sensitivity and higher data rate transmission over a longer plastic optical fiber length. Integrated optical receivers and transmitters with high linearity are introduced for multilevel communication. For binary high-data rate transmission over plastic optical fibers, an innovative receiver containing an equalizer is described leading also to a high performance of a plastic optical fiber link. The cheap standard PMMA SI-POF (step-index plastic optical fiber) has the lowest bandwidth and the highest attenuation among multimode fibers. This small bandwidth limits the maximum data rate which can be transmitted through plastic optical fibers. To overcome the problem of the plastic optical fibers high transmission loss, very sensitive receivers must be used to increase the transmitted length over POF. The plastic optical fiber li...

Water quality determination by photographic analysis. [optical density and water turbidity

Science.gov (United States)

Klooster, S. A.; Scherz, J. P.

1973-01-01

Aerial reconnaissance techniques to extract water quality parameters from aerial photos are reported. The turbidity can be correlated with total suspended solids if the constituent parts of the effluent remain the same and the volumetric flow remains relatively constant. A monochromator is used for the selection of the bandwidths containing the most information. White reflectance panels are used to locate sampling points and eliminate inherent energy changes from lens flare, radial lens fall-off, and changing subject illumination. Misleading information resulting from bottom effects is avoided by the use of Secchi disc readings and proper choice of wavelength for analyzing the photos.

UHV mirror mounts for photophysics beamline at Indus-I

International Nuclear Information System (INIS)

Meenakshi Raja Rao, P.; Bhattacharya, S.S.; Das, N.C.; Rajasekhar, B.N.; Roy, A.P.

1995-01-01

Photophysics beamline makes use of a combination of two toroidal mirrors and one meter Seya-Namioka Monochromator in its fore optics. The fore optics monochromatises and steers the synchrotron radiation source (SRS) beam from its tangent point to the sample situated at a distance of about five meters. Slit widths of the monochromator are of the order of 100μ and the sample size is one mm 2 . Hence it is essential to impart precision rotational and translational movements of the same order of magnitude to the mirrors with the use of appropriate mirror mounts. Since Indus-1 operates at a pressure -9 mbar, the mirror mounts should be UHV compatible and the movements should be actuated under UHV. The mirrors along with the mirror mounts are enclosed in UHV chambers. The mirror chambers have been fabricated at Centre for Advanced Technology (CAT) workshops and tested up to a pressure of 10 -9 mbar. The mirror mounts are designed, fabricated and leak checked (He leak rate -10 std cc/s) The precision movements are achieved with the help of bellow sealed shaft mechanism and adjustable screws provided with the kinematic mount of the mirror frame. The performance of the mirror mount was tested at atmospheric pressure by using a laser beam and found to be good. The minimum displacement of the laser beam at slit and sample positions is ∼ 70μ which is quite adequate for optical alignment. The performance of the mirror mount under UHV conditions is being evaluated. (author). 4 refs., 3 figs

Performance of a high-resolution x-ray microprobe at the Advanced Photon Source

International Nuclear Information System (INIS)

Cai, Z.; Lai, B.; Yun, W.; McNulty, I.; Khounsary, A.; Maser, J.; Ilinski, P.; Legnini, D.; Trakhtenberg, E.; Xu, S.; Tieman, B.; Wiemerslage, G.; Gluskin, E.

1999-01-01

The authors have developed a x-ray microprobe in the energy region from 6 to 20 keV using undulator radiation and zone-plate optics for microfocusing-based techniques and applications at a beamline at the Advanced Photon Source (APS). The performance of the beamline was shown to meet the design objectives, including preservation of the source brilliance and coherence, selectable transverse coherence length and energy bandwidth, high angular stability, and harmonic suppression of the beam. These objectives were achieved by careful thermal management and use of a novel mirror and crystal monochromator cooling geometry. All beamline optical components are water cooled, and the x-ray beam in the experiment station is stable in beam intensity, energy, and position over many days with no active feedback. Using a double-crystal Si(111) monochromator, they have obtained a focal spot size (FWHM) of 0.15 (micro)m (v) x 1.0 (micro)m (h), and a photon flux of 4 x 10 9 photons/sec at the focal spot, and thus a photon flux density gain of 15,000. A circular beam spot of 0.15 (micro)m in diameter can be achieved by reducing the horizontal source size using a white beam slit located 43.5 meters upstream of the zone plate, with an order of magnitude less flux in the focal spot

Top-emitting organic light-emitting diodes.

Science.gov (United States)

Hofmann, Simone; Thomschke, Michael; Lüssem, Björn; Leo, Karl

2011-11-07

We review top-emitting organic light-emitting diodes (OLEDs), which are beneficial for lighting and display applications, where non-transparent substrates are used. The optical effects of the microcavity structure as well as the loss mechanisms are discussed. Outcoupling techniques and the work on white top-emitting OLEDs are summarized. We discuss the power dissipation spectra for a monochrome and a white top-emitting OLED and give quantitative reports on the loss channels. Furthermore, the development of inverted top-emitting OLEDs is described.

High-pressure pair distribution function (PDF) measurement using high-energy focused x-ray beam

Energy Technology Data Exchange (ETDEWEB)

Hong, Xinguo, E-mail: xhong@bnl.gov; Weidner, Donald J. [Mineral Physics Institute, Stony Brook University, Stony Brook, NY 11794 (United States); Ehm, Lars [Mineral Physics Institute, Stony Brook University, Stony Brook, NY 11794 (United States); National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973 (United States); Zhong, Zhong; Ghose, Sanjit [National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973 (United States); Duffy, Thomas S. [Department of Geosciences, Princeton University, Princeton, NJ 08544 (United States)

2016-07-27

In this paper, we report recent development of the high-pressure pair distribution function (HP-PDF) measurement technique using a focused high-energy X-ray beam coupled with a diamond anvil cell (DAC). The focusing optics consist of a sagittally bent Laue monochromator and Kirkpatrick-Baez (K–B) mirrors. This combination provides a clean high-energy X-ray beam suitable for HP-PDF research. Demonstration of the HP-PDF technique for nanocrystalline platinum under quasi-hydrostatic condition above 30 GPa is presented.

Design of a high-resolution high-stability positioning mechanism for crystal optics

International Nuclear Information System (INIS)

Shu, D.; Toellner, T. S.; Alp, E. E.

1999-01-01

The authors present a novel miniature multi-axis driving structure that will allow positioning of two crystals with better than 50-nrad angular resolution and nanometer linear driving sensitivity.The precision and stability of this structure allow the user to align or adjust an assembly of crystals to achieve the same performance as does a single channel-cut crystal, so they call it an artificial channel-cut crystal. In this paper, the particular designs and specifications, as well as the test results,for a two-axis driving structure for a high-energy-resolution artificial channel-cut crystal monochromator are presented

Semi-automated high-efficiency reflectivity chamber for vacuum UV measurements

Science.gov (United States)

Wiley, James; Fleming, Brian; Renninger, Nicholas; Egan, Arika

2017-08-01

This paper presents the design and theory of operation for a semi-automated reflectivity chamber for ultraviolet optimized optics. A graphical user interface designed in LabVIEW controls the stages, interfaces with the detector system, takes semi-autonomous measurements, and monitors the system in case of error. Samples and an optical photodiode sit on an optics plate mounted to a rotation stage in the middle of the vacuum chamber. The optics plate rotates the samples and diode between an incident and reflected position to measure the absolute reflectivity of the samples at wavelengths limited by the monochromator operational bandpass of 70 nm to 550 nm. A collimating parabolic mirror on a fine steering tip-tilt motor enables beam steering for detector peak-ups. This chamber is designed to take measurements rapidly and with minimal oversight, increasing lab efficiency for high cadence and high accuracy vacuum UV reflectivity measurements.

Applied optics and optical design

CERN Document Server

Conrady, Alexander Eugen

1957-01-01

""For the optical engineer it is an indispensable work."" - Journal, Optical Society of America""As a practical guide this book has no rival."" - Transactions, Optical Society""A noteworthy contribution,"" - Nature (London)Part I covers all ordinary ray-tracing methods, together with the complete theory of primary aberrations and as much of higher aberration as is needed for the design of telescopes, low-power microscopes and simple optical systems. Chapters: Fundamental Equations, Spherical Aberration, Physical Aspect of Optical Images, Chromatic Aberration, Design of Achromatic Object-Glass

A novel optical tool for controlling and probing ultrafast surface dynamics

International Nuclear Information System (INIS)

Yang, Yudong

2017-12-01

laser pulse spectrum is then broadened via self-phase modulation by means of propagation through a gas-filled hollow-core fiber. The output pulses, spectrally broadened and temporally stretched, are recompressed with double-chirped mirrors. The compressed few-cycle pulses are characterized with SHG-FROG. The pulse characterization difficulties due to the broad bandwidth associated with few-cycle pulses have been tackled by exploiting the FROG trace frequency marginal correction. The pulse duration is measured to be 5.3 fs. The few-cycle pulses are then used for HHG in the attosecond pulse generation setup. The generated XUV pulses are characterized with an XUV spectrometer, which is equipped with varied line space gratings and an XUV CCD camera as detector. An XUV continuum, indicating the generation of isolated attosecond pulses, has been obtained with the attosecond pulse generation setup via double optical gating. The XUV continuum supports pulse durations shorter than 300 as. Meanwhile, obvious CEP effects on the XUV continuum strongly support the generation of isolated attosecond pulses. Full characterization of the attosecond pulses requires measurement of a photoelectron energy spectrogram in the presence of both the streaking IR and XUV fields. The XUV beam is focused by a gold coated toroidal mirror with grazing incidence. The delay between the XUV pulses and the IR pulses is controlled by varying the difference between the arm lengths of a Mach-Zehnder interferometer. A FROG-CRAB photoelectron spectrogram, which is used for attosecond pulse characterization, has been measured. The highly demanding interferometric stability for attosecond streaking experiments is achieved passively thanks to an elaborate vibration decoupling design of our vacuum system. In contrast to the broad bandwidth of the XUV continuum required for generating attosecond pulses, narrow bandwidth XUV sources with tunability are important for photoelectron spectroscopy experiments requiring

A novel optical tool for controlling and probing ultrafast surface dynamics

Energy Technology Data Exchange (ETDEWEB)

Yang, Yudong

2017-12-15

laser pulse spectrum is then broadened via self-phase modulation by means of propagation through a gas-filled hollow-core fiber. The output pulses, spectrally broadened and temporally stretched, are recompressed with double-chirped mirrors. The compressed few-cycle pulses are characterized with SHG-FROG. The pulse characterization difficulties due to the broad bandwidth associated with few-cycle pulses have been tackled by exploiting the FROG trace frequency marginal correction. The pulse duration is measured to be 5.3 fs. The few-cycle pulses are then used for HHG in the attosecond pulse generation setup. The generated XUV pulses are characterized with an XUV spectrometer, which is equipped with varied line space gratings and an XUV CCD camera as detector. An XUV continuum, indicating the generation of isolated attosecond pulses, has been obtained with the attosecond pulse generation setup via double optical gating. The XUV continuum supports pulse durations shorter than 300 as. Meanwhile, obvious CEP effects on the XUV continuum strongly support the generation of isolated attosecond pulses. Full characterization of the attosecond pulses requires measurement of a photoelectron energy spectrogram in the presence of both the streaking IR and XUV fields. The XUV beam is focused by a gold coated toroidal mirror with grazing incidence. The delay between the XUV pulses and the IR pulses is controlled by varying the difference between the arm lengths of a Mach-Zehnder interferometer. A FROG-CRAB photoelectron spectrogram, which is used for attosecond pulse characterization, has been measured. The highly demanding interferometric stability for attosecond streaking experiments is achieved passively thanks to an elaborate vibration decoupling design of our vacuum system. In contrast to the broad bandwidth of the XUV continuum required for generating attosecond pulses, narrow bandwidth XUV sources with tunability are important for photoelectron spectroscopy experiments requiring

Measurement of the Stokes parameters of light

International Nuclear Information System (INIS)

Berry, H.G.; Gabrielse, G.; Livingston, A.E.

1977-01-01

We describe a measuring system for determing the state of polarization of a beam of light in terms of its Stokes parameters. The technique which can be fully automated incorporates a monochromator and single photon counting detection and can thus be applied over a large wavelength range for very weak optical signals. Fourier transformation of the data by an on-line minicomputer allows immediate calculation of the Stokes parameters. We discuss special applications to light emitted from excited atomic systems with and without cylindrical symmetry

Chromatic characterization of a three-channel colorimeter using back-propagation neural networks

Science.gov (United States)

Pardo, P. J.; Pérez, A. L.; Suero, M. I.

2004-09-01

This work describes a method for the chromatic characterization of a three-channel colorimeter of recent design and construction dedicated to color vision research. The colorimeter consists of two fixed monochromators and a third monochromator interchangeable with a cathode ray tube or any other external light source. Back-propagation neural networks were used for the chromatic characterization to establish the relationship between each monochromator's input parameters and the tristimulus values of each chromatic stimulus generated. The results showed the effectiveness of this type of neural-network-based system for the chromatic characterization of the stimuli produced by any monochromator.

A compact soft x-ray (0.1–1.2 keV) calibration bench for radiometric measurements using an original versatile Rowland circle grazing incidence monochromator

Energy Technology Data Exchange (ETDEWEB)

Hubert, S., E-mail: sebastien.hubert@cea.fr

2017-05-21

This paper describes an original Rowland circle grazing incidence spectrometer used as a monochromator for a soft x-ray Manson source in order to calibrate both the source and detectors over the 0.1–1.2 keV spectral range. The originality of the instrument lies on a patented vacuum manipulator which allows the simultaneous boarding of two detectors, one (reference) for measuring the monochromatic radiation and the second to be calibrated. In order to achieve this, the vacuum manipulator is able to interchange, in vacuum, one detector with the other in front of the exit slit of the monochromatizing stage. One purpose of this apparatus was to completely eliminate the intrinsic bremsstrahlung emission of the x-ray diode source and isolate each characteristic line for quantitative detector calibrations. Obtained spectral resolution (Δλ/λ<10{sup −2}) and spectral purity (>98%) fully meet this objective. Initially dimensioned to perform calibration of bulky x-ray cameras unfolded on the Laser MégaJoule Facility, other kinds of detector can be obviously calibrated using this instrument. A brief presentation of the first calibration of an x-ray CCD through its quantum efficiency (QE) measurement is included in this paper as example. Comparison with theoretical model for QE and previous measurements at higher energy are finally presented and discussed.

Atmospheric scanning electron microscope for correlative microscopy.

Science.gov (United States)

Morrison, Ian E G; Dennison, Clare L; Nishiyama, Hidetoshi; Suga, Mitsuo; Sato, Chikara; Yarwood, Andrew; O'Toole, Peter J

2012-01-01

The JEOL ClairScope is the first truly correlative scanning electron and optical microscope. An inverted scanning electron microscope (SEM) column allows electron images of wet samples to be obtained in ambient conditions in a biological culture dish, via a silicon nitride film window in the base. A standard inverted optical microscope positioned above the dish holder can be used to take reflected light and epifluorescence images of the same sample, under atmospheric conditions that permit biochemical modifications. For SEM, the open dish allows successive staining operations to be performed without moving the holder. The standard optical color camera used for fluorescence imaging can be exchanged for a high-sensitivity monochrome camera to detect low-intensity fluorescence signals, and also cathodoluminescence emission from nanophosphor particles. If these particles are applied to the sample at a suitable density, they can greatly assist the task of perfecting the correlation between the optical and electron images. Copyright © 2012 Elsevier Inc. All rights reserved.

Continuous registration of optical absorption spectra of periodically produced solvated electrons

International Nuclear Information System (INIS)

Krebs, P.

1975-01-01

Absorption spectra of unstable intermediates, such as solvated electrons, were usually taken point by point, recording the time-dependent light absorption after their production by a flash. The experimental arrangement for continuous recording of the spectra consists of a conventional one beam spectral photometer with a stabilized white light source, a monochromator, and a light detector. By periodic production of light absorbing intermediates such as solvated electrons, e.g., by ac uv light, a small ac signal is modulated on the light detector output which after amplification can be continuously recorded as a function of wavelength. This method allows the detection of absorption spectra when disturbances from the outside provide a signal-to-noise ratio smaller than 1

Optics

CERN Document Server

Mathieu, Jean Paul

1975-01-01

Optics, Parts 1 and 2 covers electromagnetic optics and quantum optics. The first part of the book examines the various of the important properties common to all electromagnetic radiation. This part also studies electromagnetic waves; electromagnetic optics of transparent isotropic and anisotropic media; diffraction; and two-wave and multi-wave interference. The polarization states of light, the velocity of light, and the special theory of relativity are also examined in this part. The second part is devoted to quantum optics, specifically discussing the classical molecular theory of optical p

Light Optics for Optical Stochastic Cooling

Energy Technology Data Exchange (ETDEWEB)

Andorf, Matthew [NICADD, DeKalb; Lebedev, Valeri [Fermilab; Piot, Philippe [NICADD, DeKalb; Ruan, Jinhao [Fermilab

2016-06-01

In Optical Stochastic Cooling (OSC) radiation generated by a particle in a "pickup" undulator is amplified and transported to a downstream "kicker" undulator where it interacts with the same particle which radiated it. Fermilab plans to carry out both passive (no optical amplifier) and active (optical amplifier) tests of OSC at the Integrable Optics Test Accelerator (IOTA) currently in construction*. The performace of the optical system is analyzed with simulations in Synchrotron Radiation Workshop (SRW) accounting for the specific temporal and spectral properties of undulator radiation and being augmented to include dispersion of lens material.

Optical materials

International Nuclear Information System (INIS)

Poker, D.B.; Ortiz, C.

1989-01-01

This book reports on: Diamond films, Synthesis of optical materials, Structure related optical properties, Radiation effects in optical materials, Characterization of optical materials, Deposition of optical thin films, and Optical fibers and waveguides

Beamline for X-ray Free Electron Laser of SACLA

International Nuclear Information System (INIS)

Tono, K; Togashi, T; Ohashi, H; Kimura, H; Takahashi, S; Takeshita, K; Tomizawa, H; Goto, S; Inubushi, Y; Sato, T; Yabashi, M

2013-01-01

A beamline for X-ray free electron laser (XFEL) has been developed at SACLA, SPring-8 Angstrom Compact free electron LAser. The beamline delivers and diagnoses an XFEL beam without degrading the beam quality. The transport optics are applicable in the range of 4–30 keV with a double-crystal monochromator or 4–15 keV with either of two double-mirror systems. A photon diagnostic system of the beamline monitors intensity, photon energy, center-of-mass position, and spatial profile in shot-by-shot and non-destructive manners.

A METHOD FOR RECORDING AND VIEWING STEREOSCOPIC IMAGES IN COLOUR USING MULTICHROME FILTERS

DEFF Research Database (Denmark)

2000-01-01

in a conventional stereogram recorded of the scene. The invention makes use of a colour-based encoding technique and viewing filters selected so that the human observer receives, in one eye, an image of nearly full colour information, in the other eye, an essentially monochrome image supplying the parallactic......The aim of the invention is to create techniques for the encoding, production and viewing of stereograms, supplemented by methods for selecting certain optical filters needed in these novel techniques, thus providing a human observer with stereograms each of which consist of a single image...

Design and performance of U7B beamline and X-ray diffraction and scattering station at NSRL and its preliminary experiments in protein crystallography

International Nuclear Information System (INIS)

Pan Guoqiang; Xu, Chaoyin; Fan Rong; Gao Chen; Lou Xiaohua; Teng Maikun; Huang Qingqiu; Niu Liwen

2005-01-01

This publication describes the design and performance of the U7B beamline and X-ray diffraction and diffuse scattering station at National Synchrotron Radiation Laboratory (NSRL). The beamline optics comprise a Pt-coated toroidal focusing mirror and a double-crystal Si(1 1 1) monochromator. A preliminary experiment of diffraction data collection and processing was carried out using a commercial imaging plate detector system (Mar345). The data collected from one single crystal of acutohaemolysin, a Lys49-type PLA2 from Agkistrodon acutus venom, are of high quality

Chirality in nonlinear optics and optical switching

NARCIS (Netherlands)

Meijer, E.W.; Feringa, B.L.

1993-01-01

Chirality in molecular opto-electronics is limited sofar to the use of optically active liquid crystals and a number of optical phenomena are related to the helical macroscopic structure obtained by using one enantiomer, only. In this paper, the use of chirality in nonlinear optics and optical

Optics

CERN Document Server

Fincham, W H A

2013-01-01

Optics: Ninth Edition Optics: Ninth Edition covers the work necessary for the specialization in such subjects as ophthalmic optics, optical instruments and lens design. The text includes topics such as the propagation and behavior of light; reflection and refraction - their laws and how different media affect them; lenses - thick and thin, cylindrical and subcylindrical; photometry; dispersion and color; interference; and polarization. Also included are topics such as diffraction and holography; the limitation of beams in optical systems and its effects; and lens systems. The book is recommen

Imminent Cardiac Risk Assessment via Optical Intravascular Biochemical Analysis

Energy Technology Data Exchange (ETDEWEB)

Wetzel, D.; Wetzel, L; Wetzel, M; Lodder, R

2009-01-01

still the first line of defense. However, with the fidelity of 64-slice CT imaging, this technique has recently become an option when the patient presents with symptoms of reduced arterial flow. Single photon emission computerized tomography (SPECT) treadmill exercise testing is a standard non-invasive test for decreased perfusion of heart muscle, but is time consuming and not suited for emergent evaluation. Once the invasive clinical option of catherization is chosen, this provides the opportunity for intravascular ultrasound (IVUS) imaging. As the probe is pulled through the artery, the diameter at different parts is measurable, and monochrome contrast in the constricted area reveals the presence of tissue with a different ultrasonic response. Also, via an optical catheter with a fiber-optic conductor, the possibly of spectroscopic analysis of arterial walls is now a reality. In this case, the optical transducer is coupled to a near-infrared spectrometer. Revealing the arterial chemical health means that plaque vulnerability and imminent risk could be assessed by the physician. The classical emergency use of catherization involves a contrast agent and dynamic X-ray imaging to locate the constriction, determine its severity, and possibly perform angioplasty, and stent placement.

Optic neuritis

Science.gov (United States)

Retro-bulbar neuritis; Multiple sclerosis - optic neuritis; Optic nerve - optic neuritis ... The exact cause of optic neuritis is unknown. The optic nerve carries visual information from your eye to the brain. The nerve can swell when ...

Semiconductor optical amplifier-based all-optical gates for high-speed optical processing

DEFF Research Database (Denmark)

Stubkjær, Kristian

2000-01-01

Semiconductor optical amplifiers are useful building blocks for all-optical gates as wavelength converters and OTDM demultiplexers. The paper reviews the progress from simple gates using cross-gain modulation and four-wave mixing to the integrated interferometric gates using cross-phase modulation....... These gates are very efficient for high-speed signal processing and open up interesting new areas, such as all-optical regeneration and high-speed all-optical logic functions...

Bio-Optics and Bio-Inspired Optical Materials.

Science.gov (United States)

Tadepalli, Sirimuvva; Slocik, Joseph M; Gupta, Maneesh K; Naik, Rajesh R; Singamaneni, Srikanth

2017-10-25

Through the use of the limited materials palette, optimally designed micro- and nanostructures, and tightly regulated processes, nature demonstrates exquisite control of light-matter interactions at various length scales. In fact, control of light-matter interactions is an important element in the evolutionary arms race and has led to highly engineered optical materials and systems. In this review, we present a detailed summary of various optical effects found in nature with a particular emphasis on the materials and optical design aspects responsible for their optical functionality. Using several representative examples, we discuss various optical phenomena, including absorption and transparency, diffraction, interference, reflection and antireflection, scattering, light harvesting, wave guiding and lensing, camouflage, and bioluminescence, that are responsible for the unique optical properties of materials and structures found in nature and biology. Great strides in understanding the design principles adapted by nature have led to a tremendous progress in realizing biomimetic and bioinspired optical materials and photonic devices. We discuss the various micro- and nanofabrication techniques that have been employed for realizing advanced biomimetic optical structures.

Monolithically integrated quantum dot optical modulator with Semiconductor optical amplifier for short-range optical communications

Science.gov (United States)

Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Kawanishi, Tetsuya

2015-04-01

A monolithically integrated quantum dot (QD) optical gain modulator (OGM) with a QD semiconductor optical amplifier (SOA) was successfully developed. Broadband QD optical gain material was used to achieve Gbps-order high-speed optical data transmission, and an optical gain change as high as approximately 6-7 dB was obtained with a low OGM voltage of 2.0 V. Loss of optical power due to insertion of the device was also effectively compensated for by the SOA section. Furthermore, it was confirmed that the QD-OGM/SOA device helped achieve 6.0-Gbps error-free optical data transmission over a 2.0-km-long photonic crystal fiber. We also successfully demonstrated generation of Gbps-order, high-speed, and error-free optical signals in the >5.5-THz broadband optical frequency bandwidth larger than the C-band. These results suggest that the developed monolithically integrated QD-OGM/SOA device will be an advantageous and compact means of increasing the usable optical frequency channels for short-reach communications.

Introduction to digital image processing

CERN Document Server

Pratt, William K

2013-01-01

CONTINUOUS IMAGE CHARACTERIZATION Continuous Image Mathematical Characterization Image RepresentationTwo-Dimensional SystemsTwo-Dimensional Fourier TransformImage Stochastic CharacterizationPsychophysical Vision Properties Light PerceptionEye PhysiologyVisual PhenomenaMonochrome Vision ModelColor Vision ModelPhotometry and ColorimetryPhotometryColor MatchingColorimetry ConceptsColor SpacesDIGITAL IMAGE CHARACTERIZATION Image Sampling and Reconstruction Image Sampling and Reconstruction ConceptsMonochrome Image Sampling SystemsMonochrome Image Reconstruction SystemsColor Image Sampling SystemsImage QuantizationScalar QuantizationProcessing Quantized VariablesMonochrome and Color Image QuantizationDISCRETE TWO-DIMENSIONAL LINEAR PROCESSING Discrete Image Mathematical Characterization Vector-Space Image RepresentationGeneralized Two-Dimensional Linear OperatorImage Statistical CharacterizationImage Probability Density ModelsLinear Operator Statistical RepresentationSuperposition and ConvolutionFinite-Area Superp...

A new treatment of focusing by varied-line-spacing gratings with application to the Peterson PGM system

International Nuclear Information System (INIS)

Howells, M.R.; Staub, U.

1996-11-01

We present a new treatment for a varied-line-spacing grating (VLS) as a monochromator for a soft X-ray synchrotron beamline. Our calculations for a VLS monochromator show that within the small angle approximation we can make the focal length constant, correct for primary coma and spherical aberrations at all wave lengths. This monochromator scheme has still a free choice of included angle, which can be used to optimize efficiency and it can cover a wave length range of eight octaves, distinct more compared to a plane grating monochromator scheme. The analytical calculations are in excellent agreement with our ray traces using the Shadow computer code. (author) 7 figs., tabs., 27 refs

Development and implementation of a nanotomography setup at the PETRA III beamline P05

International Nuclear Information System (INIS)

Ogurreck, Malte

2014-01-01

X-ray nanotomography is used to analyze materials on the sub-micrometer scale. Many soft biological materials, i.e. most organic tissues, can be imaged with soft X-rays. For materials with a higher electron density, such as bone or teeth, metals, and ceramics, X-ray energies of more than 10 keV need to be used. All these setups require X-ray optics for either direct imaging of the object in question or for preparing a magnified projection. The P05 Imaging Beamline for X-ray micro- and nanotomography is situated at the newly refurbished PETRA III 3 rd generation storage ring at DESY. A dedicated experiment for X-ray nanotomography at higher energies was built in one of the two experimental hutches. An X-ray optics concept tailored for this experiment was specified and an accompanying mechanics concept was devised. Based on these concepts, the experiment was designed and installed. In addition to testing the nanotomography experimental components, the beamline front end was commissioned and the influence of these components on the nanotomography experiment was investigated. Higher harmonics from the undulator and monochromator as well as beam position drifts caused by mechanical drifting the monochromator were investigated to analyze their influence on the nanotomography. The X-ray optics were tested in detail and an operational setup was achieved for both the X-ray microscopy and the cone-beam setup. The achieved resolution of the hard X-ray microscope is better than 100 nm line and space. Nanotomographies were performed on a nanoporous gold sample and a photonic glass sample. Image correlation and correction allowed to perform a reconstruction of the photonic glass sample using a filtered backprojection algorithm. The packing fraction η of the photonic glass could be successfully extracted from the 3D-dataset.

Development and implementation of a nanotomography setup at the PETRA III beamline P05

Energy Technology Data Exchange (ETDEWEB)

Ogurreck, Malte

2014-12-11

X-ray nanotomography is used to analyze materials on the sub-micrometer scale. Many soft biological materials, i.e. most organic tissues, can be imaged with soft X-rays. For materials with a higher electron density, such as bone or teeth, metals, and ceramics, X-ray energies of more than 10 keV need to be used. All these setups require X-ray optics for either direct imaging of the object in question or for preparing a magnified projection. The P05 Imaging Beamline for X-ray micro- and nanotomography is situated at the newly refurbished PETRA III 3{sup rd} generation storage ring at DESY. A dedicated experiment for X-ray nanotomography at higher energies was built in one of the two experimental hutches. An X-ray optics concept tailored for this experiment was specified and an accompanying mechanics concept was devised. Based on these concepts, the experiment was designed and installed. In addition to testing the nanotomography experimental components, the beamline front end was commissioned and the influence of these components on the nanotomography experiment was investigated. Higher harmonics from the undulator and monochromator as well as beam position drifts caused by mechanical drifting the monochromator were investigated to analyze their influence on the nanotomography. The X-ray optics were tested in detail and an operational setup was achieved for both the X-ray microscopy and the cone-beam setup. The achieved resolution of the hard X-ray microscope is better than 100 nm line and space. Nanotomographies were performed on a nanoporous gold sample and a photonic glass sample. Image correlation and correction allowed to perform a reconstruction of the photonic glass sample using a filtered backprojection algorithm. The packing fraction η of the photonic glass could be successfully extracted from the 3D-dataset.

Engineering Optics

CERN Document Server

Iizuka, Keigo

2008-01-01

Engineering Optics is a book for students who want to apply their knowledge of optics to engineering problems, as well as for engineering students who want to acquire the basic principles of optics. It covers such important topics as optical signal processing, holography, tomography, holographic radars, fiber optical communication, electro- and acousto-optic devices, and integrated optics (including optical bistability). As a basis for understanding these topics, the first few chapters give easy-to-follow explanations of diffraction theory, Fourier transforms, and geometrical optics. Practical examples, such as the video disk, the Fresnel zone plate, and many more, appear throughout the text, together with numerous solved exercises. There is an entirely new section in this updated edition on 3-D imaging.

Reconfigurable optical-to-optical frequency conversion method and apparatus

Science.gov (United States)

Zortman, William A.; Lentine, Anthony L.

2017-04-18

A photonic device is provided for impressing a modulation pattern on an optical carrier. The device includes a unit in which a photodetector and an optical microresonator are monolithically integrated. The device further includes an optical waveguide evanescently coupled to the optical microresonator and having at least an upstream portion configured to carry at least one optical carrier toward the microresonator. The optical microresonator is tunable so as to resonate with the optical carrier frequency. The optical microresonator and the photodetector are mutually coupled such that in operation, charge carriers photogenerated in the photodetector are injected into the microresonator, where the photocurrent changes the resonant conditions. In some embodiments the device is operable as an optical-to-optical frequency converter. In other embodiments the device is operable as an oscillator.

In situ visualization of thermal distortions of synchrotron radiation optics

International Nuclear Information System (INIS)

Revesz, P.; Kazimirov, A.; Bazarov, I.

2007-01-01

We have developed a new in situ method to measure heating-induced distortions of the surface of the first monochromator crystal exposed to high-power white synchrotron radiation beam. The method is based on recording the image of a stationary grid of dots captured by a CCD camera as reflected from the surface of a crystal with and without a heat load. The three-dimensional surface profile (heat bump) is then reconstructed from the distortions of the original pattern. In experiments performed at the CHESS A2 wiggler beam line we measured the heat bumps with the heights of up to 600 nm produced by a wiggler beam with total power in the range of 15-60 W incident on the (1 1 1) Si crystal at various angles between 3 deg. and 15 deg

Magneto-Optic Field Coupling in Optical Fiber Bragg Gratings

Science.gov (United States)

Carman, Gregory P. (Inventor); Mohanchandra, Panduranga K. (Inventor); Emmons, Michael C. (Inventor); Richards, William Lance (Inventor)

2016-01-01

The invention is a magneto-optic coupled magnetic sensor that comprises a standard optical fiber Bragg grating system. The system includes an optical fiber with at least one Bragg grating therein. The optical fiber has at least an inner core and a cladding that surrounds the inner core. The optical fiber is part of an optical system that includes an interrogation device that provides a light wave through the optical fiber and a system to determine the change in the index of refraction of the optical fiber. The cladding of the optical fiber comprises at least a portion of which is made up of ferromagnetic particles so that the ferromagnetic particles are subject to the light wave provided by the interrogation system. When a magnetic field is present, the ferromagnetic particles change the optical properties of the sensor directly.

Multifocal visual evoked potential in optic neuritis, ischemic optic neuropathy and compressive optic neuropathy

Science.gov (United States)

Jayaraman, Manju; Gandhi, Rashmin Anilkumar; Ravi, Priya; Sen, Parveen

2014-01-01

Purpose: To investigate the effect of optic neuritis (ON), ischemic optic neuropathy (ION) and compressive optic neuropathy (CON) on multifocal visual evoked potential (mfVEP) amplitudes and latencies, and to compare the parameters among three optic nerve disorders. Materials and Methods: mfVEP was recorded for 71 eyes of controls and 48 eyes of optic nerve disorders with subgroups of optic neuritis (ON, n = 21 eyes), ischemic optic neuropathy (ION, n = 14 eyes), and compressive optic neuropathy (CON, n = 13 eyes). The size of defect in mfVEP amplitude probability plots and relative latency plots were analyzed. The pattern of the defect in amplitude probability plot was classified according to the visual field profile of optic neuritis treatment trail (ONTT). Results: Median of mfVEP amplitude (log SNR) averaged across 60 sectors were reduced in ON (0.17 (0.13-0.33)), ION (0.14 (0.12-0.21)) and CON (0.21 (0.14-0.30)) when compared to controls. The median mfVEP relative latencies compared to controls were significantly prolonged in ON and CON group of 10.53 (2.62-15.50) ms and 5.73 (2.67-14.14) ms respectively compared to ION group (2.06 (-4.09-13.02)). The common mfVEP amplitude defects observed in probability plots were diffuse pattern in ON, inferior altitudinal defect in ION and temporal hemianopia in CON eyes. Conclusions: Optic nerve disorders cause reduction in mfVEP amplitudes. The extent of delayed latency noted in ischemic optic neuropathy was significantly lesser compared to subjects with optic neuritis and compressive optic neuropathy. mfVEP amplitudes can be used to objectively assess the topography of the visual field defect. PMID:24088641

Optical near-fields & nearfield optics

OpenAIRE

Meixner, Alfred J; Leiderer, Paul

2014-01-01

Optical methods provide exceedingly powerful tools in science and technology for measuring, analyzing and manipulating, from optical microscopy and spectroscopy to the characterization of ultrafast processes by femtosecond pulses and the modification of materials by intense laser radiation. However, when it comes to applications in the nanometer-regime, the conventional optical techniques suffer from the resolution limit – formulated by Ernst Abbe one and a half centuries ago – that light can...

Ellipsoidal capillary as condenser for the BESSY full-field x-ray microscope

International Nuclear Information System (INIS)

Guttmann, P; Heim, S; Schneider, G; Zeng, X; Feser, M; Yun, W

2009-01-01

The BESSY x-ray microscopy group has developed a new full-field x-ray microscope which employs an advanced x-ray optical concept. Traditionally, zone plate based condensers are used in x-ray microscopes providing an energy resolution of only E/ΔE ≤ 500. In addition, this conventional monochromator concept requires a pinhole close to the sample restricting the available space for tomography applications. In our new BESSY microscope, a standard monochromator beam line provides a high energy resolution of up to 10,000 which permits NEXAFS studies. An elliptically shaped mono-capillary is used to form the hollow cone illumination necessary for sample illumination and to match the aperture of the objective. Calculations regarding the performance and accuracies needed are presented and characterizations of capillaries especially made for the BESSY soft x-ray microscope are shown. For the first time, we demonstrate that glass capillaries are well suited as condensers in the soft x-ray energy domain. Their focusing efficiency was measured to be 80% which is about an order of magnitude higher than the diffraction efficiency of zone plate based condensers.

Beamline 9.3.2 - a high-resolution, bend-magnet beamline with circular polarization capability

Energy Technology Data Exchange (ETDEWEB)

Moler, E.J.; Hussain, Z.; Howells, M.R. [Lawrence Berkeley National Lab., CA (United States)] [and others

1997-04-01

Beamline 9.3.2 is a high resolution, SGM beamline on an ALS bending magnet with access to photon energies from 30-1500 eV. Features include circular polarization capability, a rotating chamber platform that allows switching between experiments without breaking vacuum, an active feedback system that keeps the beam centered on the entrance slit of the monochromator, and a bendable refocusing mirror. The beamline optics consist of horizontally and vertically focussing mirrors, a Spherical Grating Monochromator (SGM) with movable entrance and exit slits, and a bendable refocussing mirror. In addition, a movable aperature has been installed just upstream of the vertically focussing mirror which can select the x-rays above or below the plane of the synchrotron storage ring, allowing the user to select circularly or linearly polarized light. Circularly polarized x-rays are used to study the magnetic properties of materials. Beamline 9.3.2 can supply left and right circularly polarized x-rays by a computer controlled aperture which may be placed above or below the plane of the synchrotron storage ring. The degree of linear and circular polarization has been measured and calibrated.

Design of optical switches by illusion optics

International Nuclear Information System (INIS)

Shoorian, H R; Abrishamian, M S

2013-01-01

In this paper, illusion optics theory is employed to form Bragg gratings in an optical waveguide in order to design an optical switch. By using an illusion device at a certain distance from the waveguide, the effective refractive index of the waveguide is remotely modulated, turning the waveguide into a distributed Bragg reflector (DBR) which blocks the waves at a stop band. By removing the illusion device, the waves propagate through the waveguide again. In addition, this method is used to remotely tune DBR optical properties such as resonant frequency and bandwidth in a wide range, which leads to a tunable filter for optical switching applications. Finally, using an illusion device at a distance, an optical cavity is created by inserting defects remotely in a DBR without any physical damage in the primary device. (paper)

Design of optical switches by illusion optics

Science.gov (United States)

Shoorian, H. R.; Abrishamian, M. S.

2013-05-01

In this paper, illusion optics theory is employed to form Bragg gratings in an optical waveguide in order to design an optical switch. By using an illusion device at a certain distance from the waveguide, the effective refractive index of the waveguide is remotely modulated, turning the waveguide into a distributed Bragg reflector (DBR) which blocks the waves at a stop band. By removing the illusion device, the waves propagate through the waveguide again. In addition, this method is used to remotely tune DBR optical properties such as resonant frequency and bandwidth in a wide range, which leads to a tunable filter for optical switching applications. Finally, using an illusion device at a distance, an optical cavity is created by inserting defects remotely in a DBR without any physical damage in the primary device.

Progress in nano-electro optics characterization of nano-optical materials and optical near-field interactions

CERN Document Server

Ohtsu, Motoichi

2005-01-01

This volume focuses on the characterization of nano-optical materials and optical-near field interactions. It begins with the techniques for characterizing the magneto-optical Kerr effect and continues with methods to determine structural and optical properties in high-quality quantum wires with high spatial uniformity. Further topics include: near-field luminescence mapping in InGaN/GaN single quantum well structures in order to interpret the recombination mechanism in InGaN-based nano-structures; and theoretical treatment of the optical near field and optical near-field interactions, providing the basis for investigating the signal transport and associated dissipation in nano-optical devices. Taken as a whole, this overview will be a valuable resource for engineers and scientists working in the field of nano-electro-optics.

Optical Performance Monitoring and Signal Optimization in Optical Networks

DEFF Research Database (Denmark)

Petersen, Martin Nordal

2006-01-01

The thesis studies performance monitoring for the next generation optical networks. The focus is on all-optical networks with bit-rates of 10 Gb/s or above. Next generation all-optical networks offer large challenges as the optical transmitted distance increases and the occurrence of electrical-optical......-electrical regeneration points decreases. This thesis evaluates the impact of signal degrading effects that are becoming of increasing concern in all-optical high-speed networks due to all-optical switching and higher bit-rates. Especially group-velocity-dispersion (GVD) and a number of nonlinear effects will require...... enhanced attention to avoid signal degradations. The requirements for optical performance monitoring features are discussed, and the thesis evaluates the advantages and necessity of increasing the level of performance monitoring parameters in the physical layer. In particular, methods for optical...

All-optical signal processing for optical packet switching networks

NARCIS (Netherlands)

Liu, Y.; Hill, M.T.; Calabretta, N.; Tangdiongga, E.; Geldenhuys, R.; Zhang, S.; Li, Z.; Waardt, de H.; Khoe, G.D.; Dorren, H.J.S.; Iftekharuddin, K.M.; awwal, A.A.S.

2005-01-01

We discuss how all-optical signal processing might play a role in future all-optical packet switched networks. We introduce a concept of optical packet switches that employ entirely all-optical signal processing technology. The optical packet switch is made out of three functional blocks: the

Optimized Spectrometers Characterization Procedure for Near Ground Support of ESA FLEX Observations: Part 1 Spectral Calibration and Characterisation

Directory of Open Access Journals (Sweden)

Laura Mihai

2018-02-01

Full Text Available The paper presents two procedures for the wavelength calibration, in the oxygen telluric absorption spectral bands (O2-A, λc = 687 nm and O2-B, λc = 760.6 nm, of field fixed-point spectrometers used for reflectance and Sun-induced fluorescence measurements. In the first case, Ne and Ar pen-type spectral lamps were employed, while the second approach is based on a double monochromator setup. The double monochromator system was characterized for the estimation of errors associated with different operating configurations. The proposed methods were applied to three Piccolo Doppio-type systems built around two QE Pros and one USB2 + H16355 Ocean Optics spectrometers. The wavelength calibration errors for all the calibrations performed on the three spectrometers are reported and potential methodological improvements discussed. The suggested calibration methods were validated, as the wavelength corrections obtained by both techniques for the QE Pro designed for fluorescence investigations were similar. However, it is recommended that a neon emission line source, as well as an argon or mercury-argon source be used to have a reference wavelength closer to the O2-B feature. The wavelength calibration can then be optimised as close to the O2-B and O2-A features as possible. The monochromator approach could also be used, but that instrument would need to be fully characterized prior to use, and although it may offer a more accurate calibration, as it could be tuned to emit light at the same wavelengths as the absorption features, it would be more time consuming as it is a scanning approach.

Nano-metrology: The art of measuring X-ray mirrors with slope errors <100 nrad

Energy Technology Data Exchange (ETDEWEB)

Alcock, Simon G., E-mail: simon.alcock@diamond.ac.uk; Nistea, Ioana; Sawhney, Kawal [Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom)

2016-05-15

We present a comprehensive investigation of the systematic and random errors of the nano-metrology instruments used to characterize synchrotron X-ray optics at Diamond Light Source. With experimental skill and careful analysis, we show that these instruments used in combination are capable of measuring state-of-the-art X-ray mirrors. Examples are provided of how Diamond metrology data have helped to achieve slope errors of <100 nrad for optical systems installed on synchrotron beamlines, including: iterative correction of substrates using ion beam figuring and optimal clamping of monochromator grating blanks in their holders. Simulations demonstrate how random noise from the Diamond-NOM’s autocollimator adds into the overall measured value of the mirror’s slope error, and thus predict how many averaged scans are required to accurately characterize different grades of mirror.

I18--the microfocus spectroscopy beamline at the Diamond Light Source.

Science.gov (United States)

Mosselmans, J Frederick W; Quinn, Paul D; Dent, Andrew J; Cavill, Stuart A; Moreno, Sofia Diaz; Peach, Andrew; Leicester, Peter J; Keylock, Stephen J; Gregory, Simon R; Atkinson, Kirk D; Rosell, Josep Roque

2009-11-01

The design and performance of the microfocus spectroscopy beamline at the Diamond Light Source are described. The beamline is based on a 27 mm-period undulator to give an operable energy range between 2 and 20.7 keV, enabling it to cover the K-edges of the elements from P to Mo and the L(3)-edges from Sr to Pu. Micro-X-ray fluorescence, micro-EXAFS and micro-X-ray diffraction have all been achieved on the beamline with a spot size of approximately 3 microm. The principal optical elements of the beamline consist of a toroid mirror, a liquid-nitrogen-cooled double-crystal monochromator and a pair of bimorph Kirkpatrick-Baez mirrors. The performance of the optics is compared with theoretical values and a few of the early experimental results are summarized.

Nano-metrology: The art of measuring X-ray mirrors with slope errors <100 nrad

International Nuclear Information System (INIS)

Alcock, Simon G.; Nistea, Ioana; Sawhney, Kawal

2016-01-01

We present a comprehensive investigation of the systematic and random errors of the nano-metrology instruments used to characterize synchrotron X-ray optics at Diamond Light Source. With experimental skill and careful analysis, we show that these instruments used in combination are capable of measuring state-of-the-art X-ray mirrors. Examples are provided of how Diamond metrology data have helped to achieve slope errors of <100 nrad for optical systems installed on synchrotron beamlines, including: iterative correction of substrates using ion beam figuring and optimal clamping of monochromator grating blanks in their holders. Simulations demonstrate how random noise from the Diamond-NOM’s autocollimator adds into the overall measured value of the mirror’s slope error, and thus predict how many averaged scans are required to accurately characterize different grades of mirror.

Nano-metrology: The art of measuring X-ray mirrors with slope errors <100 nrad.

Science.gov (United States)

Alcock, Simon G; Nistea, Ioana; Sawhney, Kawal

2016-05-01

We present a comprehensive investigation of the systematic and random errors of the nano-metrology instruments used to characterize synchrotron X-ray optics at Diamond Light Source. With experimental skill and careful analysis, we show that these instruments used in combination are capable of measuring state-of-the-art X-ray mirrors. Examples are provided of how Diamond metrology data have helped to achieve slope errors of <100 nrad for optical systems installed on synchrotron beamlines, including: iterative correction of substrates using ion beam figuring and optimal clamping of monochromator grating blanks in their holders. Simulations demonstrate how random noise from the Diamond-NOM's autocollimator adds into the overall measured value of the mirror's slope error, and thus predict how many averaged scans are required to accurately characterize different grades of mirror.

Spatially Resolved Gas Temperature Measurements in an Atmospheric Pressure DC Glow Microdischarge with Raman Scattering

Science.gov (United States)

Belostotskiy, S.; Wang, Q.; Donnelly, V.; Economou, D.; Sadeghi, N.

2006-10-01

Spatially resolved rotational Raman spectroscopy of ground state nitrogen N2(X^1σg^+) was used to measure the gas temperature (Tg) in a nitrogen dc glow microdischarge (gap between electrodes d˜500 μm). An original backscattering, confocal optical system was developed for collecting Raman spectra. Stray laser light and Raleigh scattering were blocked by using a triple grating monochromator and spatial filters, designed specifically for these experiments. The optical system provided a spatial resolution of electrodes, Tg increased linearly with jd, reaching 500 K at 1000 mA/cm^2 jd for a pressure of 720 Torr. Spatially resolved gas temperature measurements will also be presented and discussed in combination with a mathematical model for gas heating in the microplasma. This work is supported by DoE/NSF.

Electron holography at atomic dimensions -- Present state

International Nuclear Information System (INIS)

Lehmann, M.; Lichte, H.

1999-01-01

An electron microscope is a wave optical instrument where the object information is carried by an electron wave. However, an important information, the phase of the electron wave, is lost, because only intensities can be recorded in a conventional electron micrograph. Off-axis electron holography solves this phase problem by encoding amplitude and phase information in an interference pattern, the so-called hologram. After reconstruction, a rather unrestricted wave optical analysis can be performed on a computer. The possibilities as well as the current limitations of off-axis electron holography at atomic dimensions are discussed, and they are illustrated at two applications of structure characterization of ε-NbN and YBCO-1237. Finally, an electron microscope equipped with a Cs-corrector, a monochromator, and a Moellenstedt biprism is outlined for subangstrom holography

Feasibility of Optical Instruments Based on Multiaperture Optics.

Science.gov (United States)

1984-10-16

system may be configured. The optical elements may be nonimaging concentrators (light horns), the field of view (FOV) of which may be controlled by a...RD-RI58 868 FEASIBILITY OF OPTICAL INSTRUMENTS BASED ON i/I MULTIAPERTURE OPTICS (U) FLORIDA UNIV GAINESVILLE DEPT OF NUCLEAR ENGINEERING SCIENCES J D...d Subtitle) 5. TYPE OF REPORT & PERIOD COVERED ’ 0 Feasibility of Optical Instruments Based on Final Report * CD Multiaperature Optics 615/83 to 9/30

Nonlinear optics

International Nuclear Information System (INIS)

Boyd, R.W.

1992-01-01

Nonlinear optics is the study of the interaction of intense laser light with matter. This book is a textbook on nonlinear optics at the level of a beginning graduate student. The intent of the book is to provide an introduction to the field of nonlinear optics that stresses fundamental concepts and that enables the student to go on to perform independent research in this field. This book covers the areas of nonlinear optics, quantum optics, quantum electronics, laser physics, electrooptics, and modern optics

Physical optics

International Nuclear Information System (INIS)

Kim Il Gon; Lee, Seong Su; Jang, Gi Wan

2012-07-01

This book indicates physical optics with properties and transmission of light, mathematical expression of wave like harmonic wave and cylindrical wave, electromagnetic theory and light, transmission of light with Fermat principle and Fresnel equation, geometrical optics I, geometrical optics II, optical instrument such as stops, glasses and camera, polarized light like double refraction by polarized light, interference, interference by multiple reflections, diffraction, solid optics, crystal optics such as Faraday rotation and Kerr effect and measurement of light. Each chapter has an exercise.

Physical optics

Energy Technology Data Exchange (ETDEWEB)

Kim Il Gon; Lee, Seong Su; Jang, Gi Wan

2012-07-15

This book indicates physical optics with properties and transmission of light, mathematical expression of wave like harmonic wave and cylindrical wave, electromagnetic theory and light, transmission of light with Fermat principle and Fresnel equation, geometrical optics I, geometrical optics II, optical instrument such as stops, glasses and camera, polarized light like double refraction by polarized light, interference, interference by multiple reflections, diffraction, solid optics, crystal optics such as Faraday rotation and Kerr effect and measurement of light. Each chapter has an exercise.

Optics

CERN Document Server

Fincham, W H A

2013-01-01

Optics: Eighth Edition covers the work necessary for the specialization in such subjects as ophthalmic optics, optical instruments and lens design. The text includes topics such as the propagation and behavior of light; reflection and refraction - their laws and how different media affect them; lenses - thick and thin, cylindrical and subcylindrical; photometry; dispersion and color; interference; and polarization. Also included are topics such as diffraction and holography; the limitation of beams in optical systems and its effects; and lens systems. The book is recommended for engineering st

Electron optics

CERN Document Server

Grivet, Pierre; Bertein, F; Castaing, R; Gauzit, M; Septier, Albert L

1972-01-01

Electron Optics, Second English Edition, Part I: Optics is a 10-chapter book that begins by elucidating the fundamental features and basic techniques of electron optics, as well as the distribution of potential and field in electrostatic lenses. This book then explains the field distribution in magnetic lenses; the optical properties of electrostatic and magnetic lenses; and the similarities and differences between glass optics and electron optics. Subsequent chapters focus on lens defects; some electrostatic lenses and triode guns; and magnetic lens models. The strong focusing lenses and pris

On the impact of indium distribution on the electronic properties in InGaN nanodisks

KAUST Repository

Benaissa, M.

2015-03-09

We analyze an epitaxially grown heterostructure composed of InGaN nanodisks inserted in GaN nanowires in order to relate indium concentration to the electronic properties. This study was achieved with spatially resolved low-loss electron energy-loss spectroscopy using monochromated electrons to probe optical excitations - plasmons - at nanometer scale. Our findings show that each nanowire has its own indium fluctuation and therefore its own average composition. Due to this indium distribution, a scatter is obtained in plasmon energies, and therefore in the optical dielectric function, of the nanowire ensemble. We suppose that these inhomogeneous electronic properties significantly alter band-to-band transitions and consequently induce emission broadening. In addition, the observation of tailing indium composition into the GaN barrier suggests a graded well-barrier interface leading to further inhomogeneous broadening of the electro-optical properties. An improvement in the indium incorporation during growth is therefore needed to narrow the emission linewidth of the presently studied heterostructures.

A conceptual design of the set-up for solid state spectroscopy with free electron laser and insertion device radiation

CERN Document Server

Makhov, V N

2001-01-01

The set-up for complex solid state spectroscopy with the use of enhanced properties of radiation from insertion devices and free electron lasers is proposed. Very high flux and pulsed properties of radiation from insertion devices and free electron lasers offer the possibility for the use of such powerful techniques as electron paramagnetic resonance (EPR) and optically detected magnetic resonance (ODMR) for the studies of excited states of electronic excitations or defects in solids. The power density of radiation can become high enough for one more method of exited-state spectroscopy: transient optical absorption spectroscopy. The set-up is supposed to combine the EPR/ODMR spectrometer, i.e. cryostat supplied with superconducting magnet and microwave system, and the optical channels for excitation (by radiation from insertion devices or free electron laser) and detection of luminescence (i.e. primary and secondary monochromators). The set-up can be used both for 'conventional' spectroscopy of solids (reflec...

On the impact of indium distribution on the electronic properties in InGaN nanodisks

KAUST Repository

Benaissa, M.; Sigle, W.; Ng, Tien Khee; El Bouayadi, R.; van Aken, P. A.; Jahangir, S.; Bhattacharya, P.; Ooi, Boon S.

2015-01-01

We analyze an epitaxially grown heterostructure composed of InGaN nanodisks inserted in GaN nanowires in order to relate indium concentration to the electronic properties. This study was achieved with spatially resolved low-loss electron energy-loss spectroscopy using monochromated electrons to probe optical excitations - plasmons - at nanometer scale. Our findings show that each nanowire has its own indium fluctuation and therefore its own average composition. Due to this indium distribution, a scatter is obtained in plasmon energies, and therefore in the optical dielectric function, of the nanowire ensemble. We suppose that these inhomogeneous electronic properties significantly alter band-to-band transitions and consequently induce emission broadening. In addition, the observation of tailing indium composition into the GaN barrier suggests a graded well-barrier interface leading to further inhomogeneous broadening of the electro-optical properties. An improvement in the indium incorporation during growth is therefore needed to narrow the emission linewidth of the presently studied heterostructures.

Magneto-optic and electro-optic modulators

International Nuclear Information System (INIS)

Hutchinson, D.P.; Ma, C.H.; Price, T.R.; Staats, P.A.; Sluis, K.L.V.

1982-01-01

An important aspect of the Faraday rotation diagnostic for tokamak plasma measurement has been the development of suitable polarization modulators for submillimeter wavelength. The problems are to obtain high optical transmission and fast modulation frequencies. In ORNL, the authors have developed both a magneto-optic and an electro-optic submillimeter-wave modulators. These devices have been operated at modulation frequency of approximately 100 kHz, and both have high transmission. The original magneto-optic modulator consists of a 3 mm thick by 1.4 cm diameter 2-111 ferrite disk mounted at the center of an air core coil. Recently, a new ferrite modulator has been tested, which allows a much higher modulation frequency than the original device. A laboratory set-up designed to simulate a plasma heterodyne interferometer/polarimeter experiment has been used to determine the modulator characteristics. A mechanical polarization rotor was used to simulate the rotation by plasma. The transmission of the ferrite disk was 80 % at a wavelength of 0.447 mm. The authors have also performed preliminary measurement on an electro-optic modulator first demonstrated by Fetterman at Lincoln Laboratory, U.S. This device is a classical electro-optic modulator using a cryogenically cooled (4.2 K) LiTaO 3 crystal. Experiments are underway to determine the electro-optic properties of the crystal over the temperature range from 4.2 K to 77 K and over the range of wavelength from 0.118 mm to 0.447 mm. (Wakatsuki, Y.)

Generation of doublet spectral lines at self-seeded X-ray FELs

Energy Technology Data Exchange (ETDEWEB)

Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2010-11-15

Self-seeding schemes, consisting of two undulators with a monochromator in between, aim to reduce the bandwidth of SASE X-ray FELs. We recently proposed to use a new method of monochromatization exploiting a single crystal in Braggtransmission geometry for self-seeding in the hard X-ray range. The obvious and technically possible extension is to use such kind of monochromator setup with two -or more- crystals arranged in a series to spectrally filter the SASE radiation at two -or more- closely-spaced wavelengths within the FEL gain band. This allows for the production of doublet- or multiplet-spectral lines. Applications exist over a broad range of hard X-ray wavelengths involving any process where there is a large change in cross section over a narrow wavelength range, as in multiple wavelength anomalous diffraction techniques (MAD). In this paper we consider the simultaneous operation of the LCLS hard X-ray FEL at two closely spaced wavelengths. We present simulation results for the LCLS baseline, and we show that this method can produce fully coherent radiation shared between two longitudinal modes. Mode spacing can be easily tuned within the FEL gain band, i.e. within 10 eV. An interesting aspect of the proposed scheme is a way of modulating the electron bunch at optical frequencies without a seed quantum laser. In fact, the XFEL output intensity contains an oscillating ''mode-beat'' component whose frequency is related to the frequency difference between the pair of longitudinal modes considered. Thus, at saturation one obtains FEL-induced modulations of energy loss and energy spread in the electron bunch at optical frequency. These modulations can be converted into density modulation at the same optical frequency with the help of a weak chicane installed behind the baseline undulator. Powerful coherent radiation can then be generated with the help of an optical transition radiation (OTR) station,which have important applications. In this paper we briefly

Validation of an analytical method based on the high-resolution continuum source flame atomic absorption spectrometry for the fast-sequential determination of several hazardous/priority hazardous metals in soil.

Science.gov (United States)

Frentiu, Tiberiu; Ponta, Michaela; Hategan, Raluca

2013-03-01

The aim of this paper was the validation of a new analytical method based on the high-resolution continuum source flame atomic absorption spectrometry for the fast-sequential determination of several hazardous/priority hazardous metals (Ag, Cd, Co, Cr, Cu, Ni, Pb and Zn) in soil after microwave assisted digestion in aqua regia. Determinations were performed on the ContrAA 300 (Analytik Jena) air-acetylene flame spectrometer equipped with xenon short-arc lamp as a continuum radiation source for all elements, double monochromator consisting of a prism pre-monocromator and an echelle grating monochromator, and charge coupled device as detector. For validation a method-performance study was conducted involving the establishment of the analytical performance of the new method (limits of detection and quantification, precision and accuracy). Moreover, the Bland and Altman statistical method was used in analyzing the agreement between the proposed assay and inductively coupled plasma optical emission spectrometry as standardized method for the multielemental determination in soil. The limits of detection in soil sample (3σ criterion) in the high-resolution continuum source flame atomic absorption spectrometry method were (mg/kg): 0.18 (Ag), 0.14 (Cd), 0.36 (Co), 0.25 (Cr), 0.09 (Cu), 1.0 (Ni), 1.4 (Pb) and 0.18 (Zn), close to those in inductively coupled plasma optical emission spectrometry: 0.12 (Ag), 0.05 (Cd), 0.15 (Co), 1.4 (Cr), 0.15 (Cu), 2.5 (Ni), 2.5 (Pb) and 0.04 (Zn). Accuracy was checked by analyzing 4 certified reference materials and a good agreement for 95% confidence interval was found in both methods, with recoveries in the range of 94-106% in atomic absorption and 97-103% in optical emission. Repeatability found by analyzing real soil samples was in the range 1.6-5.2% in atomic absorption, similar with that of 1.9-6.1% in optical emission spectrometry. The Bland and Altman method showed no statistical significant difference between the two spectrometric

Generation of doublet spectral lines at self-seeded X-ray FELs

International Nuclear Information System (INIS)

Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

2010-11-01

Self-seeding schemes, consisting of two undulators with a monochromator in between, aim to reduce the bandwidth of SASE X-ray FELs. We recently proposed to use a new method of monochromatization exploiting a single crystal in Braggtransmission geometry for self-seeding in the hard X-ray range. The obvious and technically possible extension is to use such kind of monochromator setup with two -or more- crystals arranged in a series to spectrally filter the SASE radiation at two -or more- closely-spaced wavelengths within the FEL gain band. This allows for the production of doublet- or multiplet-spectral lines. Applications exist over a broad range of hard X-ray wavelengths involving any process where there is a large change in cross section over a narrow wavelength range, as in multiple wavelength anomalous diffraction techniques (MAD). In this paper we consider the simultaneous operation of the LCLS hard X-ray FEL at two closely spaced wavelengths. We present simulation results for the LCLS baseline, and we show that this method can produce fully coherent radiation shared between two longitudinal modes. Mode spacing can be easily tuned within the FEL gain band, i.e. within 10 eV. An interesting aspect of the proposed scheme is a way of modulating the electron bunch at optical frequencies without a seed quantum laser. In fact, the XFEL output intensity contains an oscillating ''mode-beat'' component whose frequency is related to the frequency difference between the pair of longitudinal modes considered. Thus, at saturation one obtains FEL-induced modulations of energy loss and energy spread in the electron bunch at optical frequency. These modulations can be converted into density modulation at the same optical frequency with the help of a weak chicane installed behind the baseline undulator. Powerful coherent radiation can then be generated with the help of an optical transition radiation (OTR) station,which have important applications. In this paper we briefly

Atomic optics. The optics of the year 2000?

International Nuclear Information System (INIS)

Guzman, Angela M.

1998-01-01

In atom optics the roles of light and matter are exchanged with respect to those of conventional optics. Atom optics makes possible the manipulation of atoms with lasers. This review deals with foundations and recent developments on atom optics: laser cooling and trapping, optical lattices, Bose-Einstein Condensation (BEC), and the atom laser. Main features of BEC and theoretical models for generation of a coherent atomic beam are described, indicating the technological challenges involved in their implementation. Special attention is devoted to the model of Guzman et al. perspectives and possible applications are mentioned

Magneto-optic and electro-optic modulators

International Nuclear Information System (INIS)

Hutchinson, D.P.; Ma, C.H.; Price, T.R.; Staats, P.A.; Vander Sluis, K.L.

1982-01-01

An important aspect of the Faraday rotation diagnostic for tokamak plasma measurements has been the development of suitable polarization modulators for submillimeter wavelengths. The problems are to obtain high optical transmission and fast modulation frequencies. At ORNL we have developed both a magneto-optic and an electro-optic submillimeter-wave modulators. These devices have been operated at modulation frequencies of approximately 100 kHz and both have high transmission

Sputter deposition system for controlled fabrication of multilayers

International Nuclear Information System (INIS)

Di Nardo, R.P.; Takacs, P.Z.; Majkrzak, C.F.; Stefan, P.M.

1985-06-01

A detailed description of a sputter deposition system constructed specifically for the fabrication of x-ray and neutron multilayer monochromators and supermirrors is given. One of the principal design criteria is to maintain precise control of film thickness and uniformity over large substrate areas. Regulation of critical system parameters is fully automated so that response to feedback control information is rapid and complicated layer thickness sequences can be deposited accurately and efficiently. The use of either dc or rf magnetron sources makes it possible to satisfy the diverse material requirements of both x-ray and neutron optics

International Symposium on Optics and its Applications (OPTICS-2011)

Science.gov (United States)

Bhattacherjee, Aranya B.; Calvo, Maria L.; Kazaryan, Eduard M.; Papoyan, Aram V.; Sarkisyan, Hayk A.

2012-03-01

OPTICS Logo PREFACE The papers selected for this volume were reported at the International Symposium 'Optics and its applications' (OPTICS-2011, Yerevan & Ashtarak, Armenia, September 5-9, 2011), http://www.ipr.sci.am/optics2011/. The Symposium was organized by the SPIE Armenian Student Chapter and major Armenian R&D organizations, universities and industrial companies working in the field of basic and applied optics: Institute for Physical Research of the National Academy of Sciences of Armenia, Yerevan State University, Russian-Armenian (Slavonic) University, and LT-PYRKAL Closed Joint Stock Company. OPTICS-2011 was primarily intended to support and promote the involvement of students and young scientists in various fields of modern optics, giving them the possibility to attend invited talks by prominent scientists and to present and discuss their own results. Furthermore, the Symposium allowed foreign participants from 14 countries to become acquainted with the achievements of optical science and technology in Armenia, which became a full member of the International Commission for Optics (ICO) in 2011. To follow this concept, the Symposium sessions were held in various host institutions. The creative and friendly ambience established at OPTICS-2011 promoted further international collaboration in the field and motivated many students to take up research in optics and photonics as a career. This volume of Journal of Physics: Conference Series covers thematic sections of the Symposium (both oral and poster), which represent the main fields of interest in optics for Armenian scientists: quantum optics & information, laser spectroscopy, optical properties of nanostructures, photonics & fiber optics, and optics of liquid crystals. Such wide coverage is consistent with the general scope of the Symposium, allowing all the students involved in optics to present, discuss and publish their recent results, and for those who are making their first steps in science to choose

Optical Computing

OpenAIRE

Woods, Damien; Naughton, Thomas J.

2008-01-01

We consider optical computers that encode data using images and compute by transforming such images. We give an overview of a number of such optical computing architectures, including descriptions of the type of hardware commonly used in optical computing, as well as some of the computational efficiencies of optical devices. We go on to discuss optical computing from the point of view of computational complexity theory, with the aim of putting some old, and some very recent, re...

Fibre-optic communications

CERN Document Server

Lecoy, Pierre

2010-01-01

This book describes in a comprehensive manner the components and systems of fiber optic communications and networks. The first section explains the theory of multimode and single-mode fibers, then the technological features, including manufacturing, cabling, and connecting. The second section describes the various components (passive and active optical components, integrated optics, opto-electronic transmitters and receivers, and optical amplifiers) used in fiber optic systems. Finally, the optical transmission system design is explained, and applications to optical networks and fiber optic se

FIBER OPTICS: Fibre optics: Forty years later

Science.gov (United States)

Dianov, Evgenii M.

2010-01-01

This paper presents a brief overview of the state of the art in fibre optics and its main applications: optical fibre communications, fibre lasers and fibre sensors for various physical property measurements. The future of fibre optics and the status of this important area of the modern technology in Russia are discussed.

Digital optical processing of optical communications: towards an Optical Turing Machine

Science.gov (United States)

Touch, Joe; Cao, Yinwen; Ziyadi, Morteza; Almaiman, Ahmed; Mohajerin-Ariaei, Amirhossein; Willner, Alan E.

2017-01-01

Optical computing is needed to support Tb/s in-network processing in a way that unifies communication and computation using a single data representation that supports in-transit network packet processing, security, and big data filtering. Support for optical computation of this sort requires leveraging the native properties of optical wave mixing to enable computation and switching for programmability. As a consequence, data must be encoded digitally as phase (M-PSK), semantics-preserving regeneration is the key to high-order computation, and data processing at Tb/s rates requires mixing. Experiments have demonstrated viable approaches to phase squeezing and power restoration. This work led our team to develop the first serial, optical Internet hop-count decrement, and to design and simulate optical circuits for calculating the Internet checksum and multiplexing Internet packets. The current exploration focuses on limited-lookback computational models to reduce the need for permanent storage and hybrid nanophotonic circuits that combine phase-aligned comb sources, non-linear mixing, and switching on the same substrate to avoid the macroscopic effects that hamper benchtop prototypes.

Digital optical processing of optical communications: towards an Optical Turing Machine

Directory of Open Access Journals (Sweden)

Touch Joe

2017-01-01

Full Text Available Optical computing is needed to support Tb/s in-network processing in a way that unifies communication and computation using a single data representation that supports in-transit network packet processing, security, and big data filtering. Support for optical computation of this sort requires leveraging the native properties of optical wave mixing to enable computation and switching for programmability. As a consequence, data must be encoded digitally as phase (M-PSK, semantics-preserving regeneration is the key to high-order computation, and data processing at Tb/s rates requires mixing. Experiments have demonstrated viable approaches to phase squeezing and power restoration. This work led our team to develop the first serial, optical Internet hop-count decrement, and to design and simulate optical circuits for calculating the Internet checksum and multiplexing Internet packets. The current exploration focuses on limited-lookback computational models to reduce the need for permanent storage and hybrid nanophotonic circuits that combine phase-aligned comb sources, non-linear mixing, and switching on the same substrate to avoid the macroscopic effects that hamper benchtop prototypes.

Realization of an optical interferometer based on holographic optics ...

Indian Academy of Sciences (India)

The paper describes a simple and cost effective method for the realization of an optical interferometer based on holographic optics, which use minimal bulk optical components. The optical arrangement in the proposed method involves a very simple alignment procedure and inexpensive holographic recording material is ...

Controlling lightwave in Riemann space by merging geometrical optics with transformation optics.

Science.gov (United States)

Liu, Yichao; Sun, Fei; He, Sailing

2018-01-11

In geometrical optical design, we only need to choose a suitable combination of lenses, prims, and mirrors to design an optical path. It is a simple and classic method for engineers. However, people cannot design fantastical optical devices such as invisibility cloaks, optical wormholes, etc. by geometrical optics. Transformation optics has paved the way for these complicated designs. However, controlling the propagation of light by transformation optics is not a direct design process like geometrical optics. In this study, a novel mixed method for optical design is proposed which has both the simplicity of classic geometrical optics and the flexibility of transformation optics. This mixed method overcomes the limitations of classic optical design; at the same time, it gives intuitive guidance for optical design by transformation optics. Three novel optical devices with fantastic functions have been designed using this mixed method, including asymmetrical transmissions, bidirectional focusing, and bidirectional cloaking. These optical devices cannot be implemented by classic optics alone and are also too complicated to be designed by pure transformation optics. Numerical simulations based on both the ray tracing method and full-wave simulation method are carried out to verify the performance of these three optical devices.

Research on the measurement technology and evaluation method of photobiological safety

Science.gov (United States)

Dai, Cai-hong; Wu, Zhi-feng; Chen, Bin-hua; Wang, Yan-fei; Li, Xiang-zhao; Fu, Lei

2013-12-01

Lamps and lamp system are widely used in large quantities in an era. The evaluation and control of optical radiation hazards of lamps and lamp systems is far more complicated. A special measurement and traceability facility was set up at NIM (National Institute of Metrology, China) to evaluate the optical radiation safety of lamp and lamp system, which includes a double grating spectroradiometer OL750D with two different entrance systems of spectral radiance and spectral irradiance traceable to the national primary standard of spectral irradiance by a 1000W spectral irradiance standard lamp, 40W deuterium lamp and a standard diffuser plate. The technical requirements of the measurement instrumentation used for optical radiation safety evaluation including monochromator type, wavelength accuracy, input optics, spectral scan interval and calibration sources are recommended also in this paper. Spectral radiance of a series of LED electric torches and infrared sources were measured by using the new developed system, and potential radiation hazards of retinal blue light hazard and retinal thermal hazard are calculated and evaluated. The optical radiation hazards of some samples are listed in Risk Group 2 (Moderate-Risk).

Optical fibres

CERN Document Server

Geisler, J; Boutruche, J P

1986-01-01

Optical Fibers covers numerous research works on the significant advances in optical fibers, with particular emphasis on their application.This text is composed of three parts encompassing 15 chapters. The first part deals with the manufacture of optical fibers and the materials used in their production. The second part describes optical-fiber connectors, terminals and branches. The third part is concerned with the major optoelectronic components encountered in optical-communication systems.This book will be of value to research scientists, engineers, and patent workers.

Nonlinear optics

CERN Document Server

Boyd, Robert W

2013-01-01

Nonlinear Optics is an advanced textbook for courses dealing with nonlinear optics, quantum electronics, laser physics, contemporary and quantum optics, and electrooptics. Its pedagogical emphasis is on fundamentals rather than particular, transitory applications. As a result, this textbook will have lasting appeal to a wide audience of electrical engineering, physics, and optics students, as well as those in related fields such as materials science and chemistry.Key Features* The origin of optical nonlinearities, including dependence on the polarization of light* A detailed treatment of the q

(e,2e) spectroscopy of solids with improved energy resolution

International Nuclear Information System (INIS)

Canney, S.; Brunger, M.J.; Storer, P.J.; Utteridge, S.; Vos, M.; Weigold, E.

1996-03-01

A brief overview of the (e,2e) technique as applied to solids is reported, including the spectrometer used in these studies. In particular it is described how the energy resolution of the spectrometer has been improved, by a factor of two, by the addition of an electron monochromator for production of the incident electron beam. This monochromator is also discussed in some detail. Results obtained using the monochromated beam are compared with previous data collected with a standard electron-gun source. 37 refs., 9 figs

Optical Observations of X-ray Bright, Optically Normal Galaxies

Science.gov (United States)

Sadun, Alberto C.; Aryan, N. S.; Ghosh, K. K.

2007-05-01

X-ray bright, optically normal galaxies (XBONGs) are galaxies that seem to have normal spectra and morphology, but are relatively bright x-ray sources. The large ratio of the x-ray to optical emission suggests that some activity, similar to that of active galactic nuclei (AGN), is occurring. Since the galaxies do not show any obvious sign of nuclear activity in their optical spectra, one possible explanation is that these galaxies do not have an optically thick accretion disk at small radii, as previously assumed. Previous data for NGC 7626 classifies it as an XBONG, and so we are studying optical features of this galaxy in order to determine better its features. After confirming an x-ray jet, we are now comparing this to optical features that we have found, including warped dust lanes and a possible optical jet.

All-optical microwave signal processing based on optical phase modulation

Science.gov (United States)

Zeng, Fei

This thesis presents a theoretical and experimental study of optical phase modulation and its applications in all-optical microwave signal processing, which include all-optical microwave filtering, all-optical microwave mixing, optical code-division multiple-access (CDMA) coding, and ultrawideband (UWB) signal generation. All-optical microwave signal processing can be considered as the use of opto-electronic devices and systems to process microwave signals in the optical domain, which provides several significant advantages such as low loss, low dispersion, light weight, high time bandwidth products, and immunity to electromagnetic interference. In conventional approaches, the intensity of an optical carrier is modulated by a microwave signal based on direct modulation or external modulation. The intensity-modulated optical signal is then fed to a photonic circuit or system to achieve specific signal processing functionalities. The microwave signal being processed is usually obtained based on direct detection, i.e., an opto-electronic conversion by use of a photodiode. In this thesis, the research efforts are focused on the optical phase modulation and its applications in all-optical microwave signal processing. To avoid using coherent detection which is complicated and costly, simple and effective phase modulation to intensity modulation (PM-IM) conversion schemes are pursued. Based on a theoretical study of optical phase modulation, two approaches to achieving PM-IM conversions are proposed. In the first approach, the use of chromatic dispersion induced by a dispersive device to alter the phase relationships among the sidebands and the optical carrier of a phase-modulated optical signal to realize PM-IM conversion is investigated. In the second approach, instead of using a dispersive device, the PM-IM conversion is realized based on optical frequency discrimination implemented using an optical filter. We show that the proposed PM-IM conversion schemes can be

Optical interconnects

CERN Document Server

Chen, Ray T

2006-01-01

This book describes fully embedded board level optical interconnect in detail including the fabrication of the thin-film VCSEL array, its characterization, thermal management, the fabrication of optical interconnection layer, and the integration of devices on a flexible waveguide film. All the optical components are buried within electrical PCB layers in a fully embedded board level optical interconnect. Therefore, we can save foot prints on the top real estate of the PCB and relieve packaging difficulty reduced by separating fabrication processes. To realize fully embedded board level optical

Optics for dummies

CERN Document Server

Duree, Galen C

2011-01-01

The easy way to shed light on Optics In general terms, optics is the science of light. More specifically, optics is a branch of physics that describes the behavior and properties of light?including visible, infrared, and ultraviolet?and the interaction of light with matter. Optics For Dummies gives you an approachable introduction to optical science, methods, and applications. You'll get plain-English explanations of the nature of light and optical effects; reflection, refraction, and diffraction; color dispersion; optical devices, industrial, medical, and military applicatio

Atmospheric free-space coherent optical communications with adaptive optics

Science.gov (United States)

Ting, Chueh; Zhang, Chengyu; Yang, Zikai

2017-02-01

Free-space coherent optical communications have a potential application to offer last mile bottleneck solution in future local area networks (LAN) because of their information carrier, information security and license-free status. Coherent optical communication systems using orthogonal frequency division multiplexing (OFDM) digital modulation are successfully demonstrated in a long-haul tens Giga bits via optical fiber, but they are not yet available in free space due to atmospheric turbulence-induced channel fading. Adaptive optics is recognized as a promising technology to mitigate the effects of atmospheric turbulence in free-space optics. In this paper, a free-space coherent optical communication system using an OFDM digital modulation scheme and adaptive optics (FSO OFDM AO) is proposed, a Gamma-Gamma distribution statistical channel fading model for the FSO OFDM AO system is examined, and FSO OFDM AO system performance is evaluated in terms of bit error rate (BER) versus various propagation distances.

Monolithically integrated quantum dot optical modulator with semiconductor optical amplifier for thousand and original band optical communication

Science.gov (United States)

Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Matsumoto, Atsushi; Kawanishi, Tetsuya

2016-04-01

A monolithically integrated quantum dot (QD) optical gain modulator (OGM) with a QD semiconductor optical amplifier (SOA) was successfully developed with T-band (1.0 µm waveband) and O-band (1.3 µm waveband) QD optical gain materials for Gbps-order, high-speed optical data generation. The insertion loss due to coupling between the device and the optical fiber was effectively compensated for by the SOA section. It was also confirmed that the monolithic QD-OGM/SOA device enabled >4.8 Gbps optical data generation with a clear eye opening in the T-band. Furthermore, we successfully demonstrated error-free 4.8 Gbps optical data transmissions in each of the six wavelength channels over a 10-km-long photonic crystal fiber using the monolithic QD-OGM/SOA device in multiple O-band wavelength channels, which were generated by the single QD gain chip. These results suggest that the monolithic QD-OGM/SOA device will be advantageous in ultra-broadband optical frequency systems that utilize the T+O-band for short- and medium-range optical communications.

Integrating optical, mechanical, and test software (with applications to freeform optics)

Science.gov (United States)

Genberg, Victor; Michels, Gregory; Myer, Brian

2017-10-01

Optical systems must perform under environmental conditions including thermal and mechanical loading. To predict the performance in the field, integrated analysis combining optical and mechanical software is required. Freeform and conformal optics offer many new opportunities for optical design. The unconventional geometries can lead to unconventional, and therefore unintuitive, mechanical behavior. Finite element (FE) analysis offers the ability to predict the deformations of freeform optics under various environments and load conditions. To understand the impact on optical performance, the deformations must be brought into optical analysis codes. This paper discusses several issues related to the integrated optomechanical analysis of freeform optics.

Metamaterials for light rays: ray optics without wave-optical analog in the ray-optics limit

International Nuclear Information System (INIS)

Hamilton, Alasdair C; Courtial, Johannes

2009-01-01

Volumes of sub-wavelength electromagnetic elements can act like homogeneous materials: metamaterials. In analogy, sheets of optical elements such as prisms can act ray-optically like homogeneous sheet materials. In this sense, such sheets can be considered to be metamaterials for light rays (METATOYs). METATOYs realize new and unusual transformations of the directions of transmitted light rays. We study here, in the ray-optics and scalar-wave limits, the wave-optical analog of such transformations, and we show that such an analog does not always exist. Perhaps, this is the reason why many of the ray-optical possibilities offered by METATOYs have never before been considered.

Wave-optics modeling of the optical-transport line for passive optical stochastic cooling

Science.gov (United States)

Andorf, M. B.; Lebedev, V. A.; Piot, P.; Ruan, J.

2018-03-01

Optical stochastic cooling (OSC) is expected to enable fast cooling of dense particle beams. Transition from microwave to optical frequencies enables an achievement of stochastic cooling rates which are orders of magnitude higher than ones achievable with the classical microwave based stochastic cooling systems. A subsystemcritical to the OSC scheme is the focusing optics used to image radiation from the upstream "pickup" undulator to the downstream "kicker" undulator. In this paper, we present simulation results using wave-optics calculation carried out with the SYNCHROTRON RADIATION WORKSHOP (SRW). Our simulations are performed in support to a proof-of-principle experiment planned at the Integrable Optics Test Accelerator (IOTA) at Fermilab. The calculations provide an estimate of the energy kick received by a 100-MeV electron as it propagates in the kicker undulator and interacts with the electromagnetic pulse it radiated at an earlier time while traveling through the pickup undulator.

Photonic layer security in fiber-optic networks and optical OFDM transmission

Science.gov (United States)

Wang, Zhenxing

Currently the Internet is experiencing an explosive growth in the world. Such growth leads to an increased data transmission rate demand in fiber-optical networks. Optical orthogonal frequency multiplexing (OFDM) is considered as a promising solution to achieve data rate beyond 100Gb/s per wavelength channel. In the meanwhile, because of extensive data transmission and sharing, data security has become an important problem and receives considerable attention in current research literature. This thesis focuses on data security issues at the physical layer of optical networks involving code-division multiple access (CDMA) systems and steganography methods. The thesis also covers several implementation issues in optical OFDM transmission. Optical CDMA is regarded as a good candidate to provide photonic layer security in multi-access channels. In this thesis we provide a systematic analysis of the security performance of incoherent optical CDMA codes. Based on the analysis, we proposed and experimentally demonstrated several methods to improve the security performance of the optical CDMA systems, such as applying all-optical encryption, and code hopping using nonlinear wavelength conversion. Moreover, we demonstrate that the use of wireless CDMA codes in optical systems can enhance the security in one single-user end-to-end optical channel. Optical steganography is another method to provide photonic data security and involves hiding the existence of data transmissions. In the thesis, we demonstrate that an optical steganography channel can exist in phase modulated public channels as well as traditional on-off-keying (OOK) modulated channels, without data synchronization. We also demonstrate an optical steganography system with enhanced security by utilizing temporal phase modulation techniques. Additionally, as one type of an overlay channel, the optical steganography technology can carry the sensor data collected by wireless sensor network on top of public optical

Fluidic optics

Science.gov (United States)

Whitesides, George M.; Tang, Sindy K. Y.

2006-09-01

Fluidic optics is a new class of optical system with real-time tunability and reconfigurability enabled by the introduction of fluidic components into the optical path. We describe the design, fabrication, operation of a number of fluidic optical systems, and focus on three devices, liquid-core/liquid-cladding (L2) waveguides, microfluidic dye lasers, and diffraction gratings based on flowing, crystalline lattices of bubbles, to demonstrate the integration of microfluidics and optics. We fabricate these devices in poly(dimethylsiloxane) (PDMS) with soft-lithographic techniques. They are simple to construct, and readily integrable with microanalytical or lab-on-a-chip systems.

Atom optics

International Nuclear Information System (INIS)

Balykin, V. I.; Jhe, W.

1999-01-01

Atom optics, in analogy to neutron and electron optics, deals with the realization of as a traditional elements, such as lenes, mirrors, beam splitters and atom interferometers, as well as a new 'dissipative' elements such as a slower and a cooler, which have no analogy in an another types of optics. Atom optics made the development of atom interferometer with high sensitivity for measurement of acceleration and rotational possible. The practical interest in atom optics lies in the opportunities to create atom microprobe with atom-size resolution and minimum damage of investigated objects. (Cho, G. S.)

Tunable laser optics

CERN Document Server

Duarte, FJ

2015-01-01

This Second Edition of a bestselling book describes the optics and optical principles needed to build lasers. It also highlights the optics instrumentation necessary to characterize laser emissions and focuses on laser-based optical instrumentation. The book emphasizes practical and utilitarian aspects of relevant optics including the essential theory. This revised, expanded, and improved edition contains new material on tunable lasers and discusses relevant topics in quantum optics.

Design of a cathodoluminescence image generator using a Raspberry Pi coupled to a scanning electron microscope

Science.gov (United States)

Benítez, Alfredo; Santiago, Ulises; Sanchez, John E.; Ponce, Arturo

2018-01-01

In this work, an innovative cathodoluminescence (CL) system is coupled to a scanning electron microscope and synchronized with a Raspberry Pi computer integrated with an innovative processing signal. The post-processing signal is based on a Python algorithm that correlates the CL and secondary electron (SE) images with a precise dwell time correction. For CL imaging, the emission signal is collected through an optical fiber and transduced to an electrical signal via a photomultiplier tube (PMT). CL Images are registered in a panchromatic mode and can be filtered using a monochromator connected between the optical fiber and the PMT to produce monochromatic CL images. The designed system has been employed to study ZnO samples prepared by electrical arc discharge and microwave methods. CL images are compared with SE images and chemical elemental mapping images to correlate the emission regions of the sample.

Optical interference coatings for optics and photonics [Invited].

Science.gov (United States)

Lee, Cheng-Chung

2013-01-01

Optical interference coatings play as an important role in the progress in optics and photonics. In this article we give a minireview of the evolution of optical interference coatings from the theory, the design, to the manufacture. Some interesting but challenging topics for the future are also discussed.

Ray-optics analysis of inhomogeneous optically anisotropic media

NARCIS (Netherlands)

Sluijter, M.

2010-01-01

When the optical behavior of light in a medium depends on the direction in which light is traveling, the medium is called optically anisotropic. Light is an electromagnetic wave and in this thesis, we discuss the electromagnetic theory on optical anisotropy. We do this with the assumption that the

Highly Reliable PON Optical Splitters for Optical Access Networks in Outside Environments

Science.gov (United States)

Watanabe, Hiroshi; Araki, Noriyuki; Fujimoto, Hisashi

Broadband optical access services are spreading throughout the world, and the number of fiber to the home (FTTH) subscribers is increasing rapidly. Telecom operators are constructing passive optical networks (PONs) to provide optical access services. Externally installed optical splitters for PONs are very important passive devices in optical access networks, and they must provide satisfactory performance as outdoor plant over long periods. Therefore, we calculate the failure rate of optical access networks and assign a failure rate to the optical splitters in optical access networks. The maximum cumulative failure rate of 1 × 8 optical splitters was calculated as 0.025 for an optical access fiber length of 2.1km and a 20-year operating lifetime. We examined planar lightwave circuit (PLC) type optical splitters for use as outside plant in terms of their optical characteristics and environmental reliability. We confirmed that PLC type optical splitters have sufficient optical performance for a PON splitter and sufficient reliability as outside plant in accordance with ITU-T standard values. We estimated the lifetimes of three kinds of PLC type optical splitters by using accelerated aging tests. The estimated failure rate of these splitters installed in optical access networks was below the target value for the cumulative failure rate, and we confirmed that they have sufficient reliability to maintain the quality of the network service. We developed 1 × 8 optical splitter modules with plug and socket type optical connectors and optical fiber cords for optical aerial closures designed for use as outside plant. These technologies make it easy to install optical splitters in an aerial optical closure. The optical splitter modules have sufficient optical performance levels for PONs because the insertion loss at the commercially used wavelengths of 1.31 and 1.55µm is less than the criterion established by ITU-T Recommendation G.671 for optical splitters. We performed a

Considerations for a soft x-ray spectromicroscopy beamline

International Nuclear Information System (INIS)

Winn, B.; Hao, X.; Jacobsen, C.

1996-01-01

The X-1A soft x-ray undulator at the NSLS is the source for the experimental programs in spectromicroscopy. The authors require both spatial and temporal coherence. Due to the relatively large horizontal divergence of the electron beam in the low β straight section of the x-ray storage ring, it has been possible to split the beam using a scraping mirror into two branches: X-1A used by the authors' program and X-1B used for high resolution spectroscopy. They are now rebuilding the X-1A beamline to provide improved resolving power and essentially linear trade-off between photon rate at the zone plate and resolving power for the soft x-ray spectromicroscopy experiments. This new beamline will exploit both additional floorspace due to the NSLS building expansion and increases in the brightness of the x-ray ring. The beam will be further split into two separate beamlines, both of which will use toroidal mirrors to focus the source on the monochromator entrance slits horizontally and to focus on the monochromator exit slits vertically. This separation comes at no loss of coherent flux and permits low thermal loading on the optics, since the authors need little more than the coherent fraction of the beam at the Fresnel zone plate for microfocusing. Because of the small angular acceptance for spatially coherent illumination of the zone plates and the use of an approximately satisfied Rowland condition, the monochromators have sufficient resolving power with fixed exit arms. Experiments can then be placed near the exit slits, with spatial coherence established by the exit slit size. Resolving power will be controlled by adjusting the entrance slit alone with no change of spatial coherence. The zone plates will be overfilled to be less sensitive to beam vibration and drift

Optical XOR gate

Science.gov (United States)

Vawter, G. Allen

2013-11-12

An optical XOR gate is formed as a photonic integrated circuit (PIC) from two sets of optical waveguide devices on a substrate, with each set of the optical waveguide devices including an electroabsorption modulator electrically connected in series with a waveguide photodetector. The optical XOR gate utilizes two digital optical inputs to generate an XOR function digital optical output. The optical XOR gate can be formed from III-V compound semiconductor layers which are epitaxially deposited on a III-V compound semiconductor substrate, and operates at a wavelength in the range of 0.8-2.0 .mu.m.

Fiber optic connector

Science.gov (United States)

Rajic, Slobodan; Muhs, Jeffrey D.

1996-01-01

A fiber optic connector and method for connecting composite materials within which optical fibers are imbedded. The fiber optic connector includes a capillary tube for receiving optical fibers at opposing ends. The method involves inserting a first optical fiber into the capillary tube and imbedding the unit in the end of a softened composite material. The capillary tube is injected with a coupling medium which subsequently solidifies. The composite material is machined to a desired configuration. An external optical fiber is then inserted into the capillary tube after fluidizing the coupling medium, whereby the optical fibers are coupled.

Wave-Optics Modeling of the Optical-Transport Line for Passive Optical Stochastic Cooling

Energy Technology Data Exchange (ETDEWEB)

Andorf, M. B. [NICADD, DeKalb; Lebedev, V. A. [Fermilab; Piot, P. [Fermilab; Ruan, J. [Fermilab

2018-03-01

Optical stochastic cooling (OSC) is expected to enable fast cooling of dense particle beams. Transition from microwave to optical frequencies enables an achievement of stochastic cooling rates which are orders of magnitude higher than ones achievable with the classical microwave based stochastic cooling systems. A subsytem critical to the OSC scheme is the focusing optics used to image radiation from the upstream "pickup" undulator to the downstream "kicker" undulator. In this paper, we present simulation results using wave-optics calculation carried out with the {\\sc Synchrotron Radiation Workshop} (SRW). Our simulations are performed in support to a proof-of-principle experiment planned at the Integrable Optics Test Accelerator (IOTA) at Fermilab. The calculations provide an estimate of the energy kick received by a 100-MeV electron as it propagates in the kicker undulator and interacts with the electromagnetic pulse it radiated at an earlier time while traveling through the pickup undulator.

Two mode optical fiber in space optics communication

Science.gov (United States)

Hampl, Martin

2017-11-01

In our contribution we propose to use of a two-mode optical fiber as a primary source in a transmitting optical head instead of the laser diode. The distribution of the optical intensity and the complex degree of the coherence on the output aperture of the lens that is irradiated by a step-index weakly guiding optical fiber is investigated. In our treatment we take into account weakly guided modes with polarization corrections to the propagation constant and unified theory of second order coherence and polarization of electromagnetic beams.

Stiffness of RBC optical confinement affected by optical clearing

Science.gov (United States)

Grishin, Oleg V.; Fedosov, Ivan V.; Tuchin, Valery V.

2017-03-01

In vivo optical trapping is a novel applied direction of an optical manipulation, which enables one to noninvasive measurement of mechanical properties of cells and tissues in living animals directly. But an application area of this direction is limited because strong scattering of many biological tissues. An optical clearing enables one to decrease the scattering and therefore increase a depth of light penetration, decrease a distortion of light beam, improve a resolution in imaging applications. Now novel methods had appeared for a measurement an optical clearing degree at a cellular level. But these methods aren't applicable in vivo. In this paper we present novel measurement method of estimate of the optical clearing, which are based on a measurement of optical trap stiffness. Our method may be applicable in vivo.

Quantum Optics

CERN Document Server

Walls, D F

2007-01-01

Quantum Optics gives a comprehensive coverage of developments in quantum optics over the past years. In the early chapters the formalism of quantum optics is elucidated and the main techniques are introduced. These are applied in the later chapters to problems such as squeezed states of light, resonance fluorescence, laser theory, quantum theory of four-wave mixing, quantum non-demolition measurements, Bell's inequalities, and atom optics. Experimental results are used to illustrate the theory throughout. This yields the most comprehensive and up-to-date coverage of experiment and theory in quantum optics in any textbook. More than 40 exercises helps readers test their understanding and provide practice in quantitative problem solving.

Optical-domain Compensation for Coupling between Optical Fiber Conjugate Vortex Modes

DEFF Research Database (Denmark)

Lyubopytov, Vladimir S.; Tatarczak, Anna; Lu, Xiaofeng

2016-01-01

We demonstrate for the first time optical-domain compensation for coupling between conjugate vortex modes in optical fibers. We introduce a novel method for reconstructing the complex propagation matrix of the optical fiber with straightforward implementation.......We demonstrate for the first time optical-domain compensation for coupling between conjugate vortex modes in optical fibers. We introduce a novel method for reconstructing the complex propagation matrix of the optical fiber with straightforward implementation....

Wideband optical vector network analyzer based on optical single-sideband modulation and optical frequency comb.

Science.gov (United States)

Xue, Min; Pan, Shilong; He, Chao; Guo, Ronghui; Zhao, Yongjiu

2013-11-15

A novel approach to increase the measurement range of the optical vector network analyzer (OVNA) based on optical single-sideband (OSSB) modulation is proposed and experimentally demonstrated. In the proposed system, each comb line in an optical frequency comb (OFC) is selected by an optical filter and used as the optical carrier for the OSSB-based OVNA. The frequency responses of an optical device-under-test (ODUT) are thus measured channel by channel. Because the comb lines in the OFC have fixed frequency spacing, by fitting the responses measured in all channels together, the magnitude and phase responses of the ODUT can be accurately achieved in a large range. A proof-of-concept experiment is performed. A measurement range of 105 GHz and a resolution of 1 MHz is achieved when a five-comb-line OFC with a frequency spacing of 20 GHz is applied to measure the magnitude and phase responses of a fiber Bragg grating.

Transnasal Endoscopic Optic Nerve Decompression in Post Traumatic Optic Neuropathy.

Science.gov (United States)

Gupta, Devang; Gadodia, Monica

2018-03-01

To quantify the successful outcome in patients following optic nerve decompression in post traumatic unilateral optic neuropathy in form of improvement in visual acuity. A prospective study was carried out over a period of 5 years (January 2011 to June 2016) at civil hospital Ahmedabad. Total 20 patients were selected with optic neuropathy including patients with direct and indirect trauma to unilateral optic nerve, not responding to conservative management, leading to optic neuropathy and subsequent impairment in vision and blindness. Decompression was done via Transnasal-Ethmo-sphenoidal route and outcome was assessed in form of post-operative visual acuity improvement at 1 month, 6 months and 1 year follow up. After surgical decompression complete recovery of visual acuity was achieved in 16 (80%) patients and partial recovery in 4 (20%). Endoscopic transnasal approach is beneficial in traumatic optic neuropathy not responding to steroid therapy and can prevent permanent disability if earlier intervention is done prior to irreversible damage to the nerve. Endoscopic optic nerve surgery can decompress the traumatic and oedematous optic nerve with proper exposure of orbital apex and optic canal without any major intracranial, intraorbital and transnasal complications.

Peptide Integrated Optics.

Science.gov (United States)

Handelman, Amir; Lapshina, Nadezda; Apter, Boris; Rosenman, Gil

2018-02-01

Bio-nanophotonics is a wide field in which advanced optical materials, biomedicine, fundamental optics, and nanotechnology are combined and result in the development of biomedical optical chips. Silk fibers or synthetic bioabsorbable polymers are the main light-guiding components. In this work, an advanced concept of integrated bio-optics is proposed, which is based on bioinspired peptide optical materials exhibiting wide optical transparency, nonlinear and electrooptical properties, and effective passive and active waveguiding. Developed new technology combining bottom-up controlled deposition of peptide planar wafers of a large area and top-down focus ion beam lithography provides direct fabrication of peptide optical integrated circuits. Finding a deep modification of peptide optical properties by reconformation of biological secondary structure from native phase to β-sheet architecture is followed by the appearance of visible fluorescence and unexpected transition from a native passive optical waveguiding to an active one. Original biocompatibility, switchable regimes of waveguiding, and multifunctional nonlinear optical properties make these new peptide planar optical materials attractive for application in emerging technology of lab-on-biochips, combining biomedical photonic and electronic circuits toward medical diagnosis, light-activated therapy, and health monitoring. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A study on Optical Labelling Techniques for All-Optical Networks

DEFF Research Database (Denmark)

Holm-Nielsen, Pablo Villanueva

2005-01-01

Optical switching has been proposed as an effective solution to overcoming the potential electronic bottleneck in all-optical network nodes carrying IP over WDM. The solution builds on the use of optical labelling as a mean to route packets or bursts of packets through the network. In addition...... of an intermediate wavelength between label erasure and label insertion. The above mentioned functionalities are assembled in whole network systems experiments that validates the different labelling schemes with respect to transmission, wavelength conversion, label swapping and retransmission. Optical labelling...... and specially the orthogonal schemes for optical labelling, are thus shown to be an effective solution to all-optical networks....

Viscous optical clearing agent for in vivo optical imaging

Science.gov (United States)

Deng, Zijian; Jing, Lijia; Wu, Ning; lv, Pengyu; Jiang, Xiaoyun; Ren, Qiushi; Li, Changhui

2014-07-01

By allowing more photons to reach deeper tissue, the optical clearing agent (OCA) has gained increasing attention in various optical imaging modalities. However, commonly used OCAs have high fluidity, limiting their applications in in vivo studies with oblique, uneven, or moving surfaces. In this work, we reported an OCA with high viscosity. We measured the properties of this viscous OCA, and tested its successful performances in the imaging of a living animal's skin with two optical imaging modalities: photoacoustic microscopy and optical coherence tomography. Our results demonstrated that the viscous OCA has a great potential in the study of different turbid tissues using various optical imaging modalities.

ADVANTAGES OF DIFFRACTIVE OPTICAL ELEMENTS APPLICATION IN SIMPLE OPTICAL IMAGING SYSTEMS

Directory of Open Access Journals (Sweden)

N. D. Zoric

2015-01-01

Full Text Available The paper deals with the influence of diffractive optical elements on the optical aberrations. The correction of optical aberrations was investigated in the simple optical systems with one and two lenses (singlet and doublet. The advantages of diffractive optical elements are their ability to generate arbitrary complex wave fronts from a piece of optical material that is essentially flat. The optical systems consisting of the standard surfaces were designed and optimized by using the same starting points. Further, the diffractive and aspheric surfaces were introduced into the developed systems. The resulting hybrid systems were optimized. To compare the complicity of the development of narrow field systems and wide field optical systems, the optimization has been done separately for these two types of the instruments. The optical systems were designed by using special Optical Design Software. Тhe characteristics of designed diffractive surfaces were controlled in Software DIFSYS 2.30. Due to the application of diffractive optical elements the longitudinal chromatic aberration was 5 times reduced for the narrow field systems. The absolute value of Seidel coefficient related to the spherical aberration was reduced in the range of 0.03. Considering that diffractive optical elements have the known disadvantages, like possible parasitic diffraction orders and probable decrease of the transmission, we also developed and analyzed the optical systems with combined aspheric and diffractive surfaces. A combination of the aspheric and diffractive surfaces in the optical disk system of the disk reading lens, gave cutting down of the longitudinal color aberrations almost 15 times on-axis, comparing to the lens consisting of the aspherical and standard surfaces. All of the designed diffractive optical elements possess the parameters within the fabrication limits.

Fiber optic based optical tomography sensor for monitoring plasma uniformity

International Nuclear Information System (INIS)

Benck, Eric C.; Etemadi, Kasra

2001-01-01

A new type of fiber optic based optical tomography sensor has been developed for in situ monitoring of plasma uniformity. Optical tomography inverts optical emission measurements into the actual plasma distribution without assuming radial symmetry. The new sensor is designed to operate with only two small windows and acquire the necessary data in less than a second. Optical tomography is being tested on an ICP-GEC RF plasma source. Variations in plasma uniformity are measured as a function of different plasma conditions

Optical trapping of a spherically symmetric sphere in the ray-optics regime: a model for optical tweezers upon cells

International Nuclear Information System (INIS)

Chang Yiren; Hsu Long; Chi Sien

2006-01-01

Since their invention in 1986, optical tweezers have become a popular manipulation and force measurement tool in cellular and molecular biology. However, until recently there has not been a sophisticated model for optical tweezers on trapping cells in the ray-optics regime. We present a model for optical tweezers to calculate the optical force upon a spherically symmetric multilayer sphere representing a common biological cell. A numerical simulation of this model shows that not only is the magnitude of the optical force upon a Chinese hamster ovary cell significantly three times smaller than that upon a polystyrene bead of the same size, but the distribution of the optical force upon a cell is also much different from that upon a uniform particle, and there is a 30% difference in the optical trapping stiffness of these two cases. Furthermore, under a small variant condition for the refractive indices of any adjacent layers of the sphere, this model provides a simple approximation to calculate the optical force and the stiffness of an optical tweezers system

Applied optics

International Nuclear Information System (INIS)

Orszag, A.; Antonetti, A.

1988-01-01

The 1988 progress report, of the Applied Optics laboratory, of the (Polytechnic School, France), is presented. The optical fiber activities are focused on the development of an optical gyrometer, containing a resonance cavity. The following domains are included, in the research program: the infrared laser physics, the laser sources, the semiconductor physics, the multiple-photon ionization and the nonlinear optics. Investigations on the biomedical, the biological and biophysical domains are carried out. The published papers and the congress communications are listed [fr

Optic Nerve Pit

Science.gov (United States)

... Conditions Frequently Asked Questions Español Condiciones Chinese Conditions Optic Nerve Pit What is optic nerve pit? An optic nerve pit is a ... may be seen in both eyes. How is optic pit diagnosed? If the pit is not affecting ...

Ultrafast all-optical signal processing using semiconductor optical amplifiers

NARCIS (Netherlands)

Li, Z.

2007-01-01

As the bit rate of one wavelength channel and the number of channels keep increasing in the telecommunication networks thanks to the advancement of optical transmission technologies, switching is experiencing the transition from the electrical domain to the optical domain. All-optical signal

Fibre Optic Gyroscope Developments Using Integrated Optic Components

Science.gov (United States)

Minford, W. J.; DePaula, R. M.

1988-09-01

The sensing of rotation using counterpropagating optical beams in a fiber loop (the SAGNAC effect) has gone through extensive developments and demonstrations since first proved feasible by Vali and Shorthilll in 1976. The interferometric fiber gyroscope minimum configuration2 which uses a common input-output port and single-mode filter was developed to provide the extreme high stability necessary to reach the sensitivities at low rotation rates attainable with current state-of-the-art detectors. The simplicity and performance of this configuration has led to its acceptance and wide-spread use. In order to increase the mechanical stability of this system, all single-mode fiber components are employed and a further advancement to integrated optics has enabled most of the optical functions to be placed on a single mass-producible substrate. Recent improvements in the components (eg polarization maintaining fiber and low coherence sources) have further enhanced the performance of the minimum configuration gyro. This presentation focused on the impact of LiNbO3 integrated optic components on gyroscope developments. The use of Ti-indiffused LiNbO3 waveguide optical circuits in interferometric fiber optic gyroscopes has taken two directions: to utilize only the phase modulator, or to combine many of the minimum configuration optical functions on the electro-optic substrate. The high-bandwidth phase modulator is the driving force for using LiNbO3 waveguide devices. This device allows both biasing the gyro for maximum sensitivity and closing the loop via frequency shifting, for example, thus increasing the dynamic range of the gyro and the linearity of the scale factor. Efforts to implement most of the minimum configuration optical functions onto a single LiNbO3 substrate have been led by Thomson CSF.3 They have demonstrated an interferometric gyroscope with excellent performance using a LiNbO3 optical circuit containing a Y-splitter, phase modulator, and surface

Fiber-Optic Pyrometer with Optically Powered Switch for Temperature Measurements.

Science.gov (United States)

Vázquez, Carmen; Pérez-Prieto, Sandra; López-Cardona, Juan D; Tapetado, Alberto; Blanco, Enrique; Moreno-López, Jorge; Montero, David S; Lallana, Pedro C

2018-02-06

We report the experimental results on a new infrared fiber-optic pyrometer for very localized and high-speed temperature measurements ranging from 170 to 530 °C using low-noise photodetectors and high-gain transimpedance amplifiers with a single gain mode in the whole temperature range. We also report a shutter based on an optical fiber switch which is optically powered to provide a reference signal in an optical fiber pyrometer measuring from 200 to 550 °C. The tests show the potential of remotely powering via optical means a 300 mW power-hungry optical switch at a distance of 100 m, avoiding any electromagnetic interference close to the measuring point.

Fiber-Optic Pyrometer with Optically Powered Switch for Temperature Measurements

Directory of Open Access Journals (Sweden)

Carmen Vázquez

2018-02-01

Full Text Available We report the experimental results on a new infrared fiber-optic pyrometer for very localized and high-speed temperature measurements ranging from 170 to 530 °C using low-noise photodetectors and high-gain transimpedance amplifiers with a single gain mode in the whole temperature range. We also report a shutter based on an optical fiber switch which is optically powered to provide a reference signal in an optical fiber pyrometer measuring from 200 to 550 °C. The tests show the potential of remotely powering via optical means a 300 mW power-hungry optical switch at a distance of 100 m, avoiding any electromagnetic interference close to the measuring point.

Problems of Aero-optics and Adaptive Optical Systems: Analytical Review

Directory of Open Access Journals (Sweden)

Yu. I. Shanin

2017-01-01

Full Text Available The analytical review gives the basic concepts of the aero-optics problem arising from the radiation propagation in the region of the boundary layers of a laser installation carrier aircraft. Estimates the radiation wave front distortions at its propagation in the near and far field. Presents main calculation approaches and methods to solve the gas-dynamic and optical problems in propagating laser radiation. Conducts a detailed analysis of the flows and their generating optical aberrations introduced by the aircraft turret (a projection platform of the on-board laser. Considers the effect of various factors (shock wave, difference in wall and flow temperatures on the flow pattern and the optical aberrations. Provides research data on the aero-optics obtained in the flying laboratory directly while in flight. Briefly considers the experimental research methods, diagnostic equipment, and synthesis of results while studying the aero-optics problem. Discusses some methods for mitigating the aerodynamic effects on the light propagation under flight conditions. Presents data about the passive, active, and hybrid effects on the flow in the boundary layers in order to reduce aberrations through improving the flow aerodynamics.The paper considers operation of adaptive optical systems under conditions of aero-optical distortions. Presents the study results concerning the reduction of the aero-optics effect on the characteristics of radiation in far field. Gives some research results regarding the effect on the efficiency of the adaptive system of a laser beam jitter and a time delay in the feedback signal transmission, which occur under application conditions. Provides data on adaptive correction of aero-optical wave fronts of radiation. Considers some application aspects in control systems of the on-board adaptive optics of adaptive filtration as a way to improve the efficiency of adaptive optical systems. The project in mind is to use obtained results

Optical computing, optical memory, and SBIRs at Foster-Miller

Science.gov (United States)

Domash, Lawrence H.

1994-03-01

A desktop design and manufacturing system for binary diffractive elements, MacBEEP, was developed with the optical researcher in mind. Optical processing systems for specialized tasks such as cellular automation computation and fractal measurement were constructed. A new family of switchable holograms has enabled several applications for control of laser beams in optical memories. New spatial light modulators and optical logic elements have been demonstrated based on a more manufacturable semiconductor technology. Novel synthetic and polymeric nonlinear materials for optical storage are under development in an integrated memory architecture. SBIR programs enable creative contributions from smaller companies, both product oriented and technology oriented, and support advances that might not otherwise be developed.

All-Optical Regeneration System for Optical Wavelength Division Multiplexed Communication Systems

DEFF Research Database (Denmark)

2014-01-01

The invention relates to an all-optical regeneration system for regeneration of optical wavelength division multiplexed WDM data signals in an optical WDM communication system. The system comprises a WDM-to-Optical time domain multiplexing OTDM, WDM-to-OTDM, converter, capable of converting....... The system additionally comprises an OTDM-to-WDM converter for converting the output OTDM data signal to an output WDM data signal. An input of the all-optical regenerator unit is in optical communication with an output of the WDM-to-OTDM converter, and an output of the all-optical regenerator unit...... an input WDM data signal comprising multiple wavelength channels into an input OTDM data signal comprising multiple time multiplexed time channels. The system further comprises an all-optical regenerator unit being configured for regenerating the input OTDM data signal into an output OTDM data signal...

Generation of optical vortices in an integrated optical circuit

Science.gov (United States)

Tudor, Rebeca; Kusko, Mihai; Kusko, Cristian

2017-09-01

In this work, the generation of optical vortices in an optical integrated circuit is numerically demonstrated. The optical vortices with topological charge m = ±1 are obtained by the coherent superposition of the first order modes present in a waveguide with a rectangular cross section, where the phase delay between these two propagating modes is Δφ = ±π/2. The optical integrated circuit consists of an input waveguide continued with a y-splitter. The left and the right arms of the splitter form two coupling regions K1 and K2 with a multimode output waveguide. In each coupling region, the fundamental modes present in the arms of the splitter are selectively coupled into the output waveguide horizontal and vertical first order modes, respectively. We showed by employing the beam propagation method simulations that the fine tuning of the geometrical parameters of the optical circuit makes possible the generation of optical vortices in both transverse electric (TE) and transverse magnetic (TM) modes. Also, we demonstrated that by placing a thermo-optical element on one of the y-splitter arms, it is possible to switch the topological charge of the generated vortex from m = 1 to m = -1.

Integrated optical transceiver with electronically controlled optical beamsteering

Science.gov (United States)

Davids, Paul; DeRose, Christopher; Tauke-Pedretti, Anna

2017-08-22

A beam-steering optical transceiver is provided. The transceiver includes one or more modules, each comprising an antenna chip and a control chip bonded to the antenna chip. Each antenna chip has a feeder waveguide, a plurality of row waveguides that tap off from the feeder waveguide, and a plurality of metallic nanoantenna elements arranged in a two-dimensional array of rows and columns such that each row overlies one of the row waveguides. Each antenna chip also includes a plurality of independently addressable thermo-optical phase shifters, each configured to produce a thermo-optical phase shift in a respective row. Each antenna chip also has, for each row, a row-wise heating circuit configured to produce a respective thermo-optic phase shift at each nanoantenna element along its row. The control chip includes controllable current sources for the independently addressable thermo-optical phase shifters and the row-wise heating circuits.

Integrated Optical Circuit Engineering For Optical Fiber Gyrocopes

Science.gov (United States)

Bristow, Julian P.; We, Albert C.; Keur, M.; Lukas, Greg; Ott, Daniel M...; Sriram, S.

1988-03-01

Fiber optic gyroscopes are of interest for low-cost, high performance rotation sensors. Integrated optical implementations of the processing optics offer the hope of mass-production, and associated cost reductions. The development of a suitable integrated optical system has been reported by other authors at a wavelength of 850nm [1]. Despite strong technical advantages at 1.3μm wavelength [2], no results have yet appeared. This wavelength is preferred for telecommunications applications applications, thus significantly reduced fiber costs may be realized. Lithium niobate is relatively immune from the photorefractive effect at this wavelength, whereas it is not at at 850nm [3].

Optical pulse generation using fiber lasers and integrated optics

International Nuclear Information System (INIS)

Wilcox, R.B.; Browning, D.F.; Burkhart, S.C.; VanWonterghem, B.W.

1995-01-01

We have demonstrated an optical pulse forming system using fiber and integrated optics, and have designed a multiple-output system for a proposed fusion laser facility. Our approach is an advancement over previous designs for fusion lasers, and an unusual application of fiber lasers and integrated optics

Optimisation of monochrome images

International Nuclear Information System (INIS)

Potter, R.

1983-01-01

Gamma cameras with modern imaging systems usually digitize the signals to allow storage and processing of the image in a computer. Although such computer systems are widely used for the extraction of quantitative uptake estimates and the analysis of time variant data, the vast majority of nuclear medicine images is still interpreted on the basis of an observer's visual assessment of a photographic hardcopy image. The optimisation of hardcopy devices is therefore vital and factors such as resolution, uniformity, noise grey scales and display matrices are discussed. Once optimum display parameters have been determined, routine procedures for quality control need to be established; suitable procedures are discussed. (U.K.)

Optical computing.

Science.gov (United States)

Stroke, G. W.

1972-01-01

Applications of the optical computer include an approach for increasing the sharpness of images obtained from the most powerful electron microscopes and fingerprint/credit card identification. The information-handling capability of the various optical computing processes is very great. Modern synthetic-aperture radars scan upward of 100,000 resolvable elements per second. Fields which have assumed major importance on the basis of optical computing principles are optical image deblurring, coherent side-looking synthetic-aperture radar, and correlative pattern recognition. Some examples of the most dramatic image deblurring results are shown.

Recent developments of high quality synthetic diamond single crystals for synchrotron X-ray monochromators

CERN Document Server

Freund, A K; Sellschop, J P Friedel; Burns, R C; Rebak, M

2001-01-01

For several years now, the ESRF, the University of the Witwatersrand and Messrs. De Beers Industrial Diamonds (Pty) Ltd. through their Diamond Research Laboratory, have pursued a development programme to assess and improve the quality of synthetic diamonds. Recently, in an effort to study the influence of nitrogen impurities on the defect structure, X-ray excited optical luminescence and spatially resolved double-crystal diffractometry were employed as new techniques. The correlation between nitrogen impurities and the raw defect structure was clearly visible. It was confirmed that concentration variations are related to lattice imperfections, where tilts are much more important than lattice constant variations. High reflectivity was observed and quite large zones of a sample bigger than 1 cm sup 2 showed to be perfect to within better than 0.5 arcsec.

Soft x-ray spectroscopy undulator beamline at the Advanced Photon Source

Energy Technology Data Exchange (ETDEWEB)

Randall, K.J.; Xu, Z.; Moore, J.F.; Gluskin, E.

1997-09-01

Construction of the high-resolution soft x ray spectroscopy undulator beamline, 2ID-C, at the Advanced Photon Source (APS) has been completed. The beamline, one of two soft x ray beamlines at the APS, will cover the photon energy range from 500 to 3,000 eV, with a maximum resolving power between 7,000 and 14,000. The optical design is based on a spherical grating monochromator (SGM) giving both high resolution and high flux throughput. Photon flux is calculated to be approximately 10{sup 12}--10{sup 13} photons per second with a beam size of approximately 1 x 1 mm{sup 2} at the sample.

Beamline I11 at Diamond: a new instrument for high resolution powder diffraction.

Science.gov (United States)

Thompson, S P; Parker, J E; Potter, J; Hill, T P; Birt, A; Cobb, T M; Yuan, F; Tang, C C

2009-07-01

The performance characteristics of a new synchrotron x-ray powder diffraction beamline (I11) at the Diamond Light Source are presented. Using an in-vacuum undulator for photon production and deploying simple x-ray optics centered around a double-crystal monochromator and a pair of harmonic rejection mirrors, a high brightness and low bandpass x-ray beam is delivered at the sample. To provide fast data collection, 45 Si(111) analyzing crystals and detectors are installed onto a large and high precision diffractometer. High resolution powder diffraction data from standard reference materials of Si, alpha-quartz, and LaB6 are used to characterize instrumental performance.

White-light full-field OCT resolution improvement by image sensor colour balance adjustment: numerical simulation

International Nuclear Information System (INIS)

Kalyanov, A L; Lychagov, V V; Ryabukho, V P; Smirnov, I V

2012-01-01

The possibility of improving white-light full-field optical coherence tomography (OCT) resolution by image sensor colour balance tuning is shown numerically. We calculated the full-width at half-maximum (FWHM) of a coherence pulse registered by a silicon colour image sensor under various colour balance settings. The calculations were made for both a halogen lamp and white LED sources. The results show that the interference pulse width can be reduced by the proper choice of colour balance coefficients. The reduction is up to 18%, as compared with a colour image sensor with regular settings, and up to 20%, as compared with a monochrome sensor. (paper)

MEMS optical sensor

DEFF Research Database (Denmark)

2013-01-01

The present invention relates to an all-optical sensor utilizing effective index modulation of a waveguide and detection of a wavelength shift of reflected light and a force sensing system accommodating said optical sensor. One embodiment of the invention relates to a sensor system comprising...... at least one multimode light source, one or more optical sensors comprising a multimode sensor optical waveguide accommodating a distributed Bragg reflector, at least one transmitting optical waveguide for guiding light from said at least one light source to said one or more multimode sensor optical...... waveguides, a detector for measuring light reflected from said Bragg reflector in said one or more multimode sensor optical waveguides, and a data processor adapted for analyzing variations in the Bragg wavelength of at least one higher order mode of the reflected light....

Optical biosensors.

Science.gov (United States)

Damborský, Pavel; Švitel, Juraj; Katrlík, Jaroslav

2016-06-30

Optical biosensors represent the most common type of biosensor. Here we provide a brief classification, a description of underlying principles of operation and their bioanalytical applications. The main focus is placed on the most widely used optical biosensors which are surface plasmon resonance (SPR)-based biosensors including SPR imaging and localized SPR. In addition, other optical biosensor systems are described, such as evanescent wave fluorescence and bioluminescent optical fibre biosensors, as well as interferometric, ellipsometric and reflectometric interference spectroscopy and surface-enhanced Raman scattering biosensors. The optical biosensors discussed here allow the sensitive and selective detection of a wide range of analytes including viruses, toxins, drugs, antibodies, tumour biomarkers and tumour cells. © 2016 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Optical Pattern Recognition

Science.gov (United States)

Yu, Francis T. S.; Jutamulia, Suganda

2008-10-01

Contributors; Preface; 1. Pattern recognition with optics Francis T. S. Yu and Don A. Gregory; 2. Hybrid neural networks for nonlinear pattern recognition Taiwei Lu; 3. Wavelets, optics, and pattern recognition Yao Li and Yunglong Sheng; 4. Applications of the fractional Fourier transform to optical pattern recognition David Mendlovic, Zeev Zalesky and Haldum M. Oxaktas; 5. Optical implementation of mathematical morphology Tien-Hsin Chao; 6. Nonlinear optical correlators with improved discrimination capability for object location and recognition Leonid P. Yaroslavsky; 7. Distortion-invariant quadratic filters Gregory Gheen; 8. Composite filter synthesis as applied to pattern recognition Shizhou Yin and Guowen Lu; 9. Iterative procedures in electro-optical pattern recognition Joseph Shamir; 10. Optoelectronic hybrid system for three-dimensional object pattern recognition Guoguang Mu, Mingzhe Lu and Ying Sun; 11. Applications of photrefractive devices in optical pattern recognition Ziangyang Yang; 12. Optical pattern recognition with microlasers Eung-Gi Paek; 13. Optical properties and applications of bacteriorhodopsin Q. Wang Song and Yu-He Zhang; 14. Liquid-crystal spatial light modulators Aris Tanone and Suganda Jutamulia; 15. Representations of fully complex functions on real-time spatial light modulators Robert W. Cohn and Laurence G. Hassbrook; Index.

Optical network democratization.

Science.gov (United States)

Nejabati, Reza; Peng, Shuping; Simeonidou, Dimitra

2016-03-06

The current Internet infrastructure is not able to support independent evolution and innovation at physical and network layer functionalities, protocols and services, while at same time supporting the increasing bandwidth demands of evolving and heterogeneous applications. This paper addresses this problem by proposing a completely democratized optical network infrastructure. It introduces the novel concepts of the optical white box and bare metal optical switch as key technology enablers for democratizing optical networks. These are programmable optical switches whose hardware is loosely connected internally and is completely separated from their control software. To alleviate their complexity, a multi-dimensional abstraction mechanism using software-defined network technology is proposed. It creates a universal model of the proposed switches without exposing their technological details. It also enables a conventional network programmer to develop network applications for control of the optical network without specific technical knowledge of the physical layer. Furthermore, a novel optical network virtualization mechanism is proposed, enabling the composition and operation of multiple coexisting and application-specific virtual optical networks sharing the same physical infrastructure. Finally, the optical white box and the abstraction mechanism are experimentally evaluated, while the virtualization mechanism is evaluated with simulation. © 2016 The Author(s).

Acousto-optic interaction in polyimide coated optical fibers with flexural waves

OpenAIRE

ALCUSA-SÁEZ, E. P.; Díez, A.; Rivera-Pérez, E.; Margulis, W.; Norin, L.; Andrés, M. V.

2017-01-01

Acousto-optic coupling in polyimide-coated single-mode optical fibers using flexural elastic waves is demonstrated. The effect of the polyimide coating on the acousto-optic interaction process is analyzed in detailed. Theoretical and experimental results are in good agreement. Although the elastic attenuation is significant, we show that acousto-optic coupling can be produced with a reasonably good efficiency. To our knowledge, it is the first experimental demonstration of acousto-optic coupl...

All-optical OXC transition strategy from WDM optical network to elastic optical network.

Science.gov (United States)

Chen, Xin; Li, Juhao; Guo, Bingli; Zhu, Paikun; Tang, Ruizhi; Chen, Zhangyuan; He, Yongqi

2016-02-22

Elastic optical network (EON) has been proposed recently as a spectrum-efficient optical layer to adapt to rapidly-increasing traffic demands instead of current deployed wavelength-division-multiplexing (WDM) optical network. In contrast with conventional WDM optical cross-connect (OXCs) based on wavelength selective switches (WSSs), the EON OXCs are based on spectrum selective switches (SSSs) which are much more expensive than WSSs, especially for large-scale switching architectures. So the transition cost from WDM OXCs to EON OXCs is a major obstacle to realizing EON. In this paper, we propose and experimentally demonstrate a transition OXC (TOXC) structure based on 2-stage cascading switching architectures, which make full use of available WSSs in current deployed WDM OXCs to reduce number and port count of required SSSs. Moreover, we propose a contention-aware spectrum allocation (CASA) scheme for EON built with the proposed TOXCs. We show by simulation that the TOXCs reduce the network capital expenditure transiting from WDM optical network to EON about 50%, with a minor traffic blocking performance degradation and about 10% accommodated traffic number detriment compared with all-SSS EON OXC architectures.

Piezo-optic and elasto-optic properties of monoclinic triglycine sulfate crystals.

Science.gov (United States)

Mytsyk, Bogdan; Demyanyshyn, Natalya; Erba, Alessandro; Shut, Viktor; Mozzharov, Sergey; Kost, Yaroslav; Mys, Oksana; Vlokh, Rostyslav

2017-12-01

For the first time, to the best of our knowledge, we have experimentally determined all of the components of the piezo-optic tensor for monoclinic crystals. This has been implemented on a specific example of triglycine sulfate crystals. Based on the results obtained, the complete elasto-optic tensor has been calculated. Acousto-optic figures of merit (AOFMs) have been estimated for the case of acousto-optic interaction occurring in the principal planes of the optical indicatrix ellipsoid and for geometries in which the highest elasto-optic coefficients are involved as effective parameters. It has been found that the highest AOFM value is equal to 6.8×10 -15   s 3 /kg for the case of isotropic acousto-optic interaction with quasi-longitudinal acoustic waves in the principal planes. This AOFM is higher than the corresponding values typical for canonic acousto-optic materials, which are transparent in the deep ultraviolet spectral range.

Total reflection x-ray fluorescence spectrometers for multielemental analysis: status of commercial equipment

International Nuclear Information System (INIS)

Ayala Jimenez, R.E.

2000-01-01

Multi-elemental analysis by total reflection x-ray fluorescence spectrometry has evolved during two decades. At the present there are commercial equipment available for the chemical analysis in all kind of biological and mineral samples. The electronic industry has also been benefited from the scientific and technological developments in the field of TXRF. The basic components of the spectrometers can be summarized as follow: a) excitation source; b) geometric arrangement (optics) for collimation and monochromatization of the primary radiation; c) x-ray detector; d) hardware and software for operation of the instrument, data acquisition and spectral deconvolution to determine the concentrations of the element present in the sample (quantitative analysis). As optional there are manufacturers offering the conventional 45 degrees geometry for direct excitation of bulky liquid or solid samples. Personal communications of the author and the commercial brochures available at the moment of writing this presentation have allowed to list the following type of components used in the TXRF spectrometers for multi-elemental analysis (the devices used in the electronic industry to analyze silicon wafers are excluded). Excitation: high power x-ray tube, output from 1300 to 2000 watts; metal ceramic low power-ray tube, output up to 50 watts. Different anodes are used but molybdenum, tungsten and copper are frequent. The excitation systems can be customized according to the requirements of the laboratory. Detector: Si-Li semi-conductor liquid nitrogen cooled; silicon solid state thermoelectrically cooled (silicon drift detector SDD and Si-PIN diode). Optics: multilayer monochromator of Si-W or Ni-C; double multilayer monochromator. Electronics: spectroscopy amplifier, analog to digital converter adapted to a PC compatible computer with software in Windows environment for the whole operation of the spectrometer and for qualy/quantitative analysis of samples are standards in the

Optics equations for aero-optical analysis

Science.gov (United States)

Sutton, George W.; Pond, John E.

2011-05-01

Aero-optical effects occur around moving air vehicles and impact passive imaging or active systems. The air flow around the vehicle is compressed, and often there is a turbulent shear and/or boundary layer both of which cause variations in the index of refraction. Examples of these are reconnaissance aircraft, the Stratospheric Observatory for Infrared Optics (SOFIA), and optically homing hypersonic interceptors. In other applications, a laser beam can be formed within the vehicle, and projected outward and focused on an object. These include the Airborne Laser Laboratory, Airborne Laser and the Airborne Tactical Laser. There are many compressible fluid mechanics computer programs that can predict the air density distribution of the surrounding flow field including density fluctuations in turbulent shear and/or boundary layers. It is necessary for the physical optics to be used to predict the properties of the ensuing image plane intensity distribution, whether passive or active. These include the time-averaged image blur circle and instantaneous realizations. (Ray tracing is a poor approximation that gives erroneous results for small aberrations.)

Automated optical assembly

Science.gov (United States)

Bala, John L.

1995-08-01

Automation and polymer science represent fundamental new technologies which can be directed toward realizing the goal of establishing a domestic, world-class, commercial optics business. Use of innovative optical designs using precision polymer optics will enable the US to play a vital role in the next generation of commercial optical products. The increased cost savings inherent in the utilization of optical-grade polymers outweighs almost every advantage of using glass for high volume situations. Optical designers must gain experience with combined refractive/diffractive designs and broaden their knowledge base regarding polymer technology beyond a cursory intellectual exercise. Implementation of a fully automated assembly system, combined with utilization of polymer optics, constitutes the type of integrated manufacturing process which will enable the US to successfully compete with the low-cost labor employed in the Far East, as well as to produce an equivalent product.

Optical system design

CERN Document Server

Fischer, Robert F

2008-01-01

Honed for more than 20 years in an SPIE professional course taught by renowned optical systems designer Robert E. Fischer, Optical System Design, Second Edition brings you the latest cutting-edge design techniques and more than 400 detailed diagrams that clearly illustrate every major procedure in optical design. This thoroughly updated resource helps you work better and faster with computer-aided optical design techniques, diffractive optics, and the latest applications, including digital imaging, telecommunications, and machine vision. No need for complex, unnecessary mathematical derivations-instead, you get hundreds of examples that break the techniques down into understandable steps. For twenty-first century optical design without the mystery, the authoritative Optical Systems Design, Second Edition features: Computer-aided design use explained through sample problems Case studies of third-millennium applications in digital imaging, sensors, lasers, machine vision, and more New chapters on optomechanic...

Beamlines at synchrotron radiation facilities: The link between the user and the machine

International Nuclear Information System (INIS)

Johnson, E.D.; Hulbert, S.L.; Berman, L.E.

1991-12-01

At this point in time the literature is full of excellent review articles which describe the operating principles of optical systems for utilizing the unique radiation provided by synchrotron storage rings. In general, the perspective provided by this body of work is that of the end user-experimenter cum optics designer. Nominal design specifications of the accelerator are usually assumed, and the impact of operation in a performance envelope which may represent either degraded or enhanced machine performance is seldom considered. In this article, we have attempted to remove ourselves from this (our own usual) perspective and look instead at the beamline as a transfer function to map from the machine to the users experiment. We open first with an introduction to the perspective of the experimentalist, and some general considerations for the interaction of beamline hardware with the machine. We then discuss phase space representations of some common components of beamlines, and then treat some important classes of crystal and geometric optics in monochromators. We then close with a discussion of some of the common features of these optical systems, and the impact of the machine on user experiments

Intelligent Optical Systems Using Adaptive Optics

Science.gov (United States)

Clark, Natalie

2012-01-01

Until recently, the phrase adaptive optics generally conjured images of large deformable mirrors being integrated into telescopes to compensate for atmospheric turbulence. However, the development of smaller, cheaper devices has sparked interest for other aerospace and commercial applications. Variable focal length lenses, liquid crystal spatial light modulators, tunable filters, phase compensators, polarization compensation, and deformable mirrors are becoming increasingly useful for other imaging applications including guidance navigation and control (GNC), coronagraphs, foveated imaging, situational awareness, autonomous rendezvous and docking, non-mechanical zoom, phase diversity, and enhanced multi-spectral imaging. The active components presented here allow flexibility in the optical design, increasing performance. In addition, the intelligent optical systems presented offer advantages in size and weight and radiation tolerance.

Polarized vacuum ultraviolet and X-radiation

International Nuclear Information System (INIS)

Samson, J.A.R.

1978-01-01

The most intense source of polarized vacuum UV and X-radiation is synchrotron radiation, which exhibits a degree of partially polarized light between about 80-100%. However, the radiation transmitted by vacuum UV monochromators can also be highly polarized. The Seya-Namioka type of monochromator can produce partially polarized radiation between 50-80%. For certain experiments it is necessary to know the degree of polarisation of the radiation being used. Also, when synchrotron radiation and a monochromator are combined the polarization characteristic of both should be known in order to make full use of these polarization properties. The polarizing effect on monochromators (i.e. diffraction gratings) have been measured at the Seya angle and at grazing angles for various spectral orders. The author presents the first experimental evidence that the reciprocity law holds for polarization by reflection where the angle of incidence and diffraction are unequal. These results are reviewed along with the techniques for measuring the degree of polarization. (Auth.)

The new polarized neutron reflectometer in Juelich