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Steven D. Phillips, Craig M. Shakarji, Michael Krystek, K Summerhays
This paper discusses the concept of metrological traceability to the SI unit of length, the meter. We describe how metrological traceability is realized, give a recent example of the standardization of laser trackers, and discuss progress and challenges to
Edward F. Kelley, Karl Lang, Louis D. Silverstein, Michael H. Brill
A standard methodology exists for estimating the flux from front projection displays by sampling the projected illuminance of a white source signal. With the advent and use of white projection primaries, a dramatic increase in flux can be achieved over the
Jack A. Stone Jr., Jennifer Decker, Patrick Gill, Andrew Lewis, Patrick Juncar, Daniele Rovera, Miguel Villiseid
The Consultative Committee for Length has recommended that red (633 nm) unstabilized Helium-Neon lasers, operating on the 3s2¿_2p4 transition, should be included in the list of standard frequencies for realization of the meter. This article discusses
Measurement of a small black area on a white electronic display screen is often accompanied by serious contamination from veiling glare in the detector. The black measurement can be thousands of percent in error. Character-stroke-contrast or small-area
Christina D. Cross, Dean C. Ripple, Gregory F. Strouse
Liquid-in-glass thermometers are pervasive in use throughout industry and provide a convenient method for measuring temperature over for a broad range of applications with reasonable stability and accuracy. However, liquid-in-glass thermometers are subject
Recent developments in optical microscopy promise to advance optical metrology and imaging to unprecedented levels through theoretical and experimental development of a new measurement technique called "scatterfield optical imaging". ". Current metrology
Linda D. Crown, Tina G. Butcher, Steven E. Cook, Lisa Warfield
This is the agenda for the four Standing Committees of the National Conference on Weights and Measures - 94th Interim Meeting. This meeting will be held at the Hilton Daytona Beach Oceanfront Resort, Daytona Beach, Florida, on January 11 to 14, 2009.
We have developed a software feedback loop that stabilizes the RF power input in calorimetric measurements to better than 30 ppm. In this system, a bolometric sensor with a Type IV power meter is used to detect the power. Feedback is provided to the AM
We describe a new, robust method of numerically extracting equivalent Raman spectra from coherent anti-Stokes Raman scattering (CARS) spectra. The extraction procedure requires no a priori information regarding the vibrational resonances or the shape of
Charles M. Guttman, Kathleen M. Flynn, William E. Wallace, Anthony J. Kearsley
The certification of an absolute molecular mass distribution polymer Standard Reference Material is described. SRM 2881 is an n octyl initiated, proton terminated, narrow polydispersity, low mass, atactic polystyrene. The absolute molecular mass
The equivalent source mismatch (GG) of a 1.85 mm coaxial power splitter was characterized using two statistical measurement techniques. The first technique, originally described by Juroshek in reference [1], uses a modified one-port calibration method to
Arkadiusz C. Lewandowski, Denis X. LeGolvan, Ronald A. Ginley, Thomas M. Wallis, Atif A. Imtiaz, Pavel Kabos
Abstract: We present a technique for accurate wideband measurements of one-port devices with extreme impedances. Our technique uses a reflectometer with variable parameters (states) to obtain redundant measurements of the extreme impedance device. We
Ronald G. Dixson, Jon R. Pratt, Vincent A. Hackley, James E. Potzick, Richard A. Allen, Ndubuisi G. Orji, Michael T. Postek, Herbert S. Bennett, Theodore V. Vorburger, Jeffrey A. Fagan, Robert L. Watters
A new era of cooperation between North American National Measurement Institutes (NMIs) was ushered by the National Research Council of Canada Institute for National Measurement Standards (NRC-INMS) on February 7, 2007 when the first Tri-National workshop
The use of flared tip and bi-directional servo control in some recent atomic force microscopes (AFM) has made it possible for these advanced AFMs to image structures of general shapes with undercuts and reentrant surfaces. Since AFM images are distorted
The simulation of microscope images computed from scattered fields determined using integral equations depend on a number of parameters that are not related to the scatterer or to the microscope but are choices made for the computation method. The effect
Singular integral equations that determine the exact fields scattered by a dielectric or conducting finite strip on a substrate are presented. The computation of the image of such a scatterer from these fields by Fourier optics methods is also shown.
John Barker, David F. Mildner, Jose Rodriguez Rivera, P. Thiyagarajan
The neutron attenuation through single-crystal magnesium fluoride has been measured as a function of wavelength at both room temperature and 77 K. These data confirm a total cross section that is lower than MgO for wavelengths greater than 0.2 nm. MgF 2
Daniel S. Sawyer, Nicholas G. Dagalakis, Craig M. Shakarji, Yong Sik Kim
Orthopedic surgeons have identified a need for calibration artifacts (phantoms) to establish the traceability (to the SI unit of length) of measurements performed with Computer Assisted Orthopedic Surgery (CAOS) systems. These phantoms must be lightweight
Jing Li, Yin-Lin Shen, Jaehwa Jeong, Fredric Scire, John A. Kramar
A compact, two-stage, vertical actuator with built-in sensors has been developed for the Molecular Measuring Machine (M3) and other potential precision instrumentation applications, such as scanning probe microscopy (SPM). In this article, we describe the
Error-motions of rotating axes are one of many sources of imprecision in machining. Accurate determination of axis of rotation error motions of the rotary axes has a direct influence on the accuracy of the finished part. International and U.S. national
Jun-Feng Song, Li Ma, Theodore V. Vorburger, Susan M. Ballou
In the ballistics measurements and correlations, optimum selection of c has particular importance for an unambiguous extraction of Individual Characteristics from the Class Characteristics . Poorly selected c might result in the Class Characteristics being
James E. Potzick, Ronald G. Dixson, Richard Quintanilha, Michael T. Stocker, Andras Vladar, Egbert Buhr, Bernd Bodermann, Wolfgang Hassler-Grohne, Harald Bosse, C.G. Frase
In preparation of the international Nano1 linewidth comparison on photomasks between 8 national metrology institutes, NIST and PTB have started a bilateral linewidth comparison in 2008, independent of and prior to the Nano1 comparison in order to test the
Ronald G. Dixson, James E. Potzick, Ndubuisi G. Orji
The National Institute of Standards and Technology (NIST) has had a robust program in photomask dimensional metrology since the late 70s when the late Diana Nyyssonen and coworkers developed the first chrome-on-glass (COG) Standard Reference Material (SRM)