Marek Dobosz
A new interferometric method for ultra-precise measurement of laser beam angular deflection is presented. Also angular tilt of measuring device in relation to the beam axis can be measured. The method is based on interference fringe period analysis in the selected plane of measurement. We proof that if the number of beam reflections in the interferometer arms differs by an odd number, then the deflection of the input beam can be measured by evaluating the change of the observed interference fringe period. The theoretical basis and experimental verification of the method are presented. Two...
TC14 LMPMI Symposium 2014
· TC14
· 2014
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Masato Aketagawa, Mumummad Madden, Eiki Okuyama
This paper describes a concurrent measurement of spindle radial, axial and angular motions using concentric circle grating and phase modulation interferometers. In the measurement, the concentric circle grating with fine pitch is a reference artifact. A frequency modulated laser diode is used for the light source of the phase modulation interferometers. The phase modulation interferometers, which consist of three Michelson and three grating interferometers, measure three radial and three axial displacements of the grating. From these six measured displacements, radial, axial and angular...
TC14 LMPMI Symposium 2014
· TC14
· 2014
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Youichi Bitou, Yohan Kondo
The special resolution of the angle-based deflectometric surface profiler has been improved by introducing a novel null instrument. Proposed null instrument is simple, inexpensive, and has fast response time. High accuracy flatness measurement for low reflective surface has been successfully demonstrated with 1 mm laser beam spot size. The repeatability of the surface form measurement is better than ±0.6 nm.
TC14 LMPMI Symposium 2014
· TC14
· 2014
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Ralf D. Geckeler, Michael Krause, Andreas Just, Oliver Kranz, Harald Bosse
An overview of the current status of angle metrology at the Physikalisch-Technische Bundesanstalt (PTB), the National Metrology Institute of Germany, is provided. Current and future challenges to angle metrology are described. Novel developments at the PTB are outlined. Our research programme is currently strongly influenced by the European Metrology Research Programme (EMRP) SIB 58 Angle Metrology project. We present our novel selfcalibration method for the fast and precise in-situ calibration of angle encoders without recourse to external reference standards which relies on a suitable...
TC14 LMPMI Symposium 2014
· TC14
· 2014
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L. Blunt, L. Fleming, M. Elrawemi, D. Robbins, H. Muhamedsalih
This paper reports on work carried out as part of the EU funded research project “Nanomend”. The project seeks to develop integrated process inspection, cleaning, repair for nano-scale thin films on large area substrates. In order to prevent water ingress into flexible PV modules they are coated with a protective barrier layer of Al 2 O 3 using atomic layer deposition (ALD) techniques. Unfortunately defects in this layer have been shown to reduce module efficiency over a period of time due to water vapour ingress. The present work concentrates on defect detection and reports on the use of...
TC14 LMPMI Symposium 2014
· TC14
· 2014
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G. B. Rossi, F. Crenna
Measurements are often an objective support for decision-making. If a measurement result can affect the decision, the measurement uncertainty associated with the result can be useful to manage the risk of a wrong decision. This is applicable to measurements in all fields, scientific, industrial or human-related. In the last case particular care has to be taken when a wrong decision can affect health, life or environment. Now, measurement-based decisions may be, with fair generality, reduced to a conformity assessment problem. Typically the state of the process under investigation is...
TC7 Symposium 2002
· TC7
· 2002
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Zygmunt L. Warsza
A new type of measuring circuitry is presented. It is an impedance bridge unconventionally supplied by two current sources connected in parallel to opposite arms of the bridge. This circuit has two independent balance states, when voltage on each output -? bridge diagonals ?- equals zero. If two current sources are ideal and identical, the equality of impedance products of neighboring arms of the output diagonal are the balance conditions. These two relations are different from the one of the classic Wheastone bridge. The author proposes to call this new type of circuits as: double current...
TC7 Symposium 2002
· TC7
· 2002
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Jorge A. Valeriano, Felipe R. Lara, Norma R. Chavez
In this work, we present the development of a methodology that is a practical guide for the design and implementation of digital measurement instruments, using Programmable Logic Devices (PLD's). Now days the programmable logic technology is a real alternative in the design of a digital systems. This is because of the growing complexity, variable specifications in the development cycle, shorter development time, and the necessity of lower costs. Additionally there are some requirements like confiability and testability. The general goal is to have a universal solution. Objectives of this...
TC7 Symposium 2002
· TC7
· 2002
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V. R. Singh
High power acoustic lithotripters, like ESWL (Extra-Corporeal Shock Wave Lithotripters), are currently in routine use in the hospitals for the removal of kidney stones, non-invasively and non-destructively. However, proper standardisation of such systems is still required for better safety purpose, and for better health care. Acoustic power output or intensity level of the lithotripter transducer is, generally, measured by using conventional devices like PVDF (polyvinyl-di-fluoride) hydrophones which have their limitation of sensitivity, stability and durability. In order to overcome such...
TC7 Symposium 2002
· TC7
· 2002
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Lyubomyr Petryshyn, Grzegorz Pedrak
On base of analysis rules theoretical and comparisons of effectivity methods of conversion analog-digital (in shortening AD), one qualified spheres most effective uses compared methods, especially for utilizations of method Monte-Carlo, one passed estimation techniques-economics characterizations conversions systems AD Monte-Carlo in aim of enlargement exactitude and speeds of conversions and processing signals. One executed analysis different methods of generating RN and passed analysis methods estimation of quality of fate schedules RN. One gave estimated estimation and results of...
TC7 Symposium 2002
· TC7
· 2002
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