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in creator/contributor: "Takacs, P.Z."

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2D Spatial Frequency Considerations in Comparing 1D Power Spectral Density Measurements

The frequency footprint of ID and 2D profiling instruments needs to be carefully considered in comparing ID surface roughness spectrum measurements made by different instruments. Contributions from orthogonal direction frequency components can not be neglected. The use of optical profiling instruments is ubiquitous in the measurement of the roughness of optical surfaces. Their ease-of-use and non-contact measurement method found widespread use in the optics industry for measuring the quality of… more

Date: June 14, 2010

Creator: Takacs, P. Z.; Barber, S.; Church, E. L.; Kaznatcheev, K.; McKinney, W. R. & Yashchuk, V. Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Accuracy Limitations in Long Trace Profilometry

As requirements for surface slope error quality of grazing incidence optics approach the 100 nanoradian level, it is necessary to improve the performance of the measuring instruments to achieve accurate and repeatable results at this level. We have identified a number of internal error sources in the Long Trace Profiler (LTP) that affect measurement quality at this level. The LTP is sensitive to phase shifts produced within the millimeter diameter of the pencil beam probe by optical path irregu… more

Date: August 25, 2003

Creator: Takacs, P. Z. & Qian, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Air Convection Noise of Pencil-Beam Interfermeter for Long Trace Profiler

In this work, we investigate the effect of air convection on laser-beam pointing noise essential for the long trace profiler (LTP). We describe this pointing error with noise power density (NPD) frequency distributions. It is shown that the NPD spectra due to air convection have a very characteristic form. In the range of frequencies from {approx}0.05 Hz to {approx}0.5 Hz, the spectra can be modeled with an inverse-power-law function. Depending on the intensity of air convection that is control… more

Date: August 14, 2006

Creator: Yashchuk, V. V.; Irick, S. C.; MacDowell, A. A.; McKinney, W. R. & Takacs, P. Z.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Application of silicon carbide to synchrotron-radiation mirrors

Damage to conventional mirror materials exposed to the harsh synchrotron radiation (SR) environment has prompted the SR user community to search for more suitable materials. Next-generation insertion devices, with their attendant flux increases, will make the problem of mirror design even more difficult. A parallel effort in searching for better materials has been underway within the laser community for several years. The technology for dealing with high thermal loads is highly developed among … more

Date: September 1, 1983

Creator: Takacs, P. Z.; Hursman, T. L. & Williams, J. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Applications of the lateral shearing interferometer in measurement of synchrotron radiation optical elements

The use of a single plate shearing, or Murty, interferometer for measuring the surface quality of several optical elements is reviewed and several results are given. The principle of the Murty interferometer is also explained. (LEW)

Date: November 1, 1987

Creator: Liu, Wu-ming; Takacs, P. Z. & Siddons, D. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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BASIC program for power spectrum estimation. Revision

A standard data set is presented to be used in testing routines that are developed for evaluating the one-dimensional periodogram spectral estimate of a series of uniformly spaced data points representing measurements of a surface profile. These data were generated using the GWBASIC program ``FFTPSD`` which is included in the Appendix of this report. The original purpose of this data set was to allow us to test and debug our own periodogram estimation routines, written in various programming, l… more

Date: May 1, 1994

Creator: Church, E. L. & Takacs, P. Z.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Binery Pseudo-Random Grating as a Standard Test Surface for Measurement of Modulation Transfer Function of Interferometric Microscopes

The task of designing high performance X-ray optical systems requires the development of sophisticated X-ray scattering calculations based on rigorous information about the optics. One of the most insightful approaches to these calculations is based on the power spectral density (PSD) distribution of the surface height. The major problem of measurement of a PSD distribution with an interferometric and/or atomic force microscope arises due to the unknown Modulation Transfer Function (MTF) of the… more

Date: August 1, 2007

Creator: Yashchuk, V. V.; McKinney, W. R. & Takacs, P. Z.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

CALIBRATION OF A VERTICAL-SCAN LONG TRACE PROFILER AT MSFC.

The long trace profiler (LTP) is the instrument of choice for the surface figure measurement of grazing incidence mirrors. The modification of conventional LTP, the vertical-scan LTP, capable of measuring the surface figure of replicated shell mirrors is now in operation at Marshall Space Flight Center. A few sources of systematic error for vertical-scan LTP are discussed. Status of systematic error reduction is reported.

Date: July 31, 2001

Creator: GUBAREV,M.; KESTER,T. & TAKACS,P.Z.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Cylinder Lens Alignment in the LTP

The Long Trace Profiler (LTP), is well-suited for the measurement of the axial figure of cylindrical mirrors that usually have a long radius of curvature in the axial direction but have a short radius of curvature in the sagittal direction. The sagittal curvature causes the probe beam to diverge in the transverse direction without coming to a focus on the detector, resulting in a very weak signal. It is useful to place a cylinder lens into the optical system above the mirror under test to refoc… more

Date: July 26, 2005

Creator: Takacs, P. Z.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development of Advanced Profiling Instrumentation for Measurement of Large Aspheric Optical Components. Final Report

No Description Available.

Date: December 31, 1994

Creator: Takacs, P Z

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development of metrology instruments for grazing incidence mirrors

The effective utilization of synchrotron radiation (SR) from high-brightness sources requires the use of optical components with very smooth surfaces and extremely precise shapes. Most manufacturers are not capable of measuring the figure and finish quality of the aspheric optics required for use in grazing incidence beam lines. Over the past several years we have developed measurement techniques and metrology instrumentation that have allowed us to measure the surface profile and roughness of … more

Date: October 1, 1989

Creator: Takacs, P.Z. (Brookhaven National Lab., Upton, NY (USA)); Church, E.L. (Army Research and Development Command, Dover, NJ (USA)); Qian, Shi-nan (China Univ. of Science and Technology, Hefei, AH (China). Hefei National Synchrotron Radiation Lab.) & Liu, Wuming (Academia Sinica, Beijing, BJ (China). Inst. of High Energy Physics)

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Evaluation of CVD silicon carbide for synchrotron radiation mirrors

Chemical vapor deposited silicon carbide (CVD SiC) is a recent addition to the list of materials suitable for use in the harsh environment of synchrotron radiation (SR) beam lines. SR mirrors for use at normal incidence must be ultrahigh vacuum compatible, must withstand intense x-ray irradiation without surface damage, must be capable of being polished to an extremely smooth surface finish, and must maintain surface figure under thermal loading. CVD SiC exceeds the performance of conventional … more

Date: July 1, 1981

Creator: Takacs, P. Z.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Evaluation techniques for x-ray mirrors and systems using visible light

Severely diffraction-broadened visible light images from grazing incidence optical systems are measured and analyzed using a diffraction integral model to predict slope errors and image quality at XUV wavelengths.

Date: September 1, 1985

Creator: Takacs, P. Z. & Colbert, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Fabrication of an 8:1 ellipsoidal mirror for a synchrotron x-ray microprobe

The fabrication of an 8:1 demagnifying ellipsoidal mirror to be used for an x-ray microprobe at the National Synchrotron Light Source X-26 beam port is described. The design aim was to produce a mirror that could be used over the photon energy range from about 3 to 17 keV. The 300-mm long mirror was required to operate at a grazing angle of 5 mr. The semimajor axis was 4500 mm and the semiminor axis 14.142 mm. Surface roughness of 1 nm or less and slope errors of 1 arc second parallel to the lo… more

Date: January 11, 1987

Creator: Jones, K. W.; Takacs, P. Z.; Hastings, J. B.; Casstevens, J. M. & Pionke, C. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Figure and finish characterization of high performance metal mirrors

Most metal mirrors currently used in synchrotron radiation (SR) beam lines to reflect soft x-rays are made of electroless nickel plate on an aluminum substrate. This material combination has allowed optical designers to incorporate exotic cylindrical aspheres into grazing incidence x-ray beam-handling systems by taking advantage of single-point diamond machining techniques. But the promise of high-quality electroless nickel surfaces has generally exceeded the performance. We will examine the ev… more

Date: October 1, 1991

Creator: Takacs, P.Z. (Brookhaven National Lab., Upton, NY (United States)) & Church, E.L. (Army Armament Research and Development Command, Dover, NJ (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Figure and finish characterization of high performance metal mirrors

Date: October 1, 1991

Creator: Takacs, P. Z. & Church, E. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Figure and finish of grazing incidence mirrors

Great improvement has been made in the past several years in the quality of optical components used in synchrotron radiation (SR) beamlines. Most of this progress has been the result of vastly improved metrology techniques and instrumentation permitting rapid and accurate measurement of the surface finish and figure on grazing incidence optics. A significant theoretical effort has linked the actual performance of components used as x-ray wavelengths to their topological properties as measured b… more

Date: August 1, 1989

Creator: Takacs, P.Z. (Brookhaven National Lab., Upton, NY (USA)) & Church, E.L. (Picatinny Arsenal, Dover, NJ (USA). Army Armament Research, Development and Engineering Center)

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Grazing incidence synchrotron radiation optics: correlation of performance with metrology

Image distortions produced by a cylinder mirror at the National Synchrotron Light Source are compared with performance predictions based on measurements of surface slope errors in the millimeter spatial period regime made with an optical surface profiler.

Date: June 1, 1986

Creator: Takacs, P. Z.; Hewitt, R. C. & Church, E. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

In search of the elusive true surface

Measurement of an optical surface by a figure measuring device allows one to make an estimate of the shape of the surface. The absolute accuracy in locating the true'' surface depends on the sources of error in the measurement process -- both random errors and systematic errors. Analysis procedures have been developed to extract surface figure information from optical profiler measurements on large mirrors. Rigid-body orientation effects are important in analyzing the shape of the off-axis elli… more

Date: August 1, 1990

Creator: Takacs, P. Z.; Furenlid, K. (Brookhaven National Lab., Upton, NY (USA)) & Church, E.L. (Army Armament Research and Development Command, Dover, NJ (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

In-situ shearing interferometry of National Synchrotron Light Source mirrors

In situ mirror distortion measurements were made with a lateral shearing interferometer on three mirrors in beam line X17T at the National Syn203hrotron Light Source. Lateral shearing interference is insensitive to vibrational motion in five of the six degrees of freedom, so it is well-suited for investigations in the synchrotron radiation (SR) environment. No distortion was seen in an uncooled silicon carbide mirror and in a colled copper alloy mirror on X17TB, but a change in the radius of an… more

Date: January 1, 1987

Creator: Qian, S. N.; Rarback, H.; Shu, D. & Takacs, P. Z.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Infra-red line IR4 at the NSLS

The authors describe the infra-red beam line which is being constructed at the NSLS. In order to maintain the high brightness at long wavelengths (up to 1 mm) where diffraction becomes a problem, a high aperture extraction port is used. Problems of cooling of the first mirror will also be discussed. Large off axis ellipsoids are used to bring the beam to a secondary focus on a mezzanine floor before entering a monochromator or being collimated for an interferometer.

Date: January 1, 1985

Creator: Williams, G. P.; Takacs, P. Z.; Klaffky, R. W. & Shleifer, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department