IMEKO Event Proceedings

Page 785 of 851 Results 7841 - 7850 of 8504

A. Lopes Ribeiro, Helena G. Ramos, J. Couto Arez
THICKNESS MEASUREMENT OF A NONMAGNETIC METALLIC PLATE USING HARMONIC EDDY CURRENT EXCITATION AND A GMR SENSOR

This paper describes the implementation of a device that measures the thickness of metallic plates. A pancake coil for magnetic field sinusoidal excitation is used and detection is performed with a bridge giant magneto-resistor sensor. The paper uses the theory of the linear transformer to explain the liftoff effect with a special attention to the point of intersection phenomenon.

M. Malesa, I. Mazurkiewicz, A. Lebek, J. Michonski, K. Malowany, M. Kujawinska
Thickness measurements of corroded district heating pipelines with utilization of Structured Light Technique

In this paper we present application of the Structured Light Illumination method for measurements of thickness of corroded district heating pipelines. The presented methodology allowed determination of the depth of pitting corrosion centres on both inner and outer sides and in each point of the pipe. Obtained data was consequently utilized for statistical analysis of corrosion growth process. The conclusions about the pitting corrosion process, as well as possible development of the presented methodology are discussed in conclusions.

S. Minamiguchi, S. Usuki, S. Takahashi, K. Takamasu
Thin film thickness measurement for evaluation of residual layer of nano-imprint lithography using near-field optics

Since a thin resin film with thickness of several 10nm remains as a residual film between the imprinted patterns and the substrate in the nano-imprint lithography process, it should be eliminated by reactive ion etching. To implement the etching process with high accuracy and to maintain the original patterns for realizing NIL as a highly reliable lithography process of semiconductor, it is seriously necessary to measure the thickness of the residual resin film before the etching process. In this article, we proposed a novel optical measurement method for the residual film thickness based on the near-field optics. As a result, the near-field optical responses are affected in relation to the film thickness and a distance between the resin surface and a fiber apex. We concluded that it is possible to measure the thin film thicknesses within 80nm with a few nm resolution by evaluating the near-field optical responses.

Jun, L., Fang, X., Shang, T.
Thinking and practicing of National Quality Infrastructure in China

Quality has always been an important issue, and it is a hot topic in the past in all parts of the world. The globalization of the markets continues its rapid pace and as it is shaped by technological developments, more and more governments are carefully reconsidering the overall arrangement of their National Quality Infrastructure, NQI. This paper covers the concept of NQI, the relationship between NQI elements, a case of application of NQI to a food productive chain and the development prospect in China.

Lars Buettner, Christian Bayer, Katsuaki Shirai, Andreas Voigt, Juergen Czarske
THREE COMPONENT FLOW IMAGING BY A 2D3C LASER DOPPLER FIELD SENSOR

We report about a novel laser Doppler field sensor, which is capable of measuring the three-component (3C) velocity field in fluid flows in a twodimensional area (2D) without mechanical scanning and without using a camera. The sensor is based on laser Doppler velocimetry but employs four superposed fan-like interference fringe systems. A spatial resolution in the sub-micrometer range can be achieved enabling highly spatially resolved flow studies. Possible applications are investigations in micro-fluidics or precision flux measurements.

S. Z. Zahwi, A. Mekawi
Three dimensional (3D) surface measurements based on (2D) stylus instrument

Three dimensional measurements (3D) of surface topography are increasingly being recognized as the most adequate method for obtaining a better understanding of surfaces. The dimensional and surface metrology department at the National Institute for Standards in Egypt (NIS) developed a computer-controlled system for 3D surface measurements. The developed system is based on a 2D surface measuring instrument using a stylus contact method. A positioning table is used to displace the specimen underneath the stylus in a cross direction to the traverse stroke. The system can scan small areas on the measured surface (5.6 mm × 0.56 mm) by traversing the stylus of the measuring instrument over the surface in parallel traces. The system consists of a “Talysurf 10” stylus surface measuring instrument interfaced to an “IBM” compatible PC computer with a data acquisition device (DAQ). The (DAQ) is used to control the movement of the measuring stroke of the pick up in the X – axis, to control the movement of the positioning table in a cross direction to the stroke as Y- axis, and to take the data of each profile from the stylus vertical movements during the measurement stroke as Z-axis.
The software for the mentioned controls is made using “Labview” programming language. All data of the 3D surface are taken using unfiltered skid less mode of operation. A “Matlab” software is developed and used to take out the trend of the surface using a least square surface plane, then an approximation of a Gaussian filter (moving average) is used to filter the data. A software to analyze the data to get the 3D surface parameters and functions is also developed.

Chu-Shik Kang, Jae Wan Kim, Jong-Ahn Kim, Tae Bong Eom
THREE DIMENSIONAL PROFILE MEASUREMENT OF FOUR-STEP REFERENCE SPECIMENS USING THE FRINGE SCANNING FOURIER TRANSFORM METHOD

A new method of three-dimensional profile measurement of four-step reference specimens is presented. Instead of measuring only the height difference between central points of the two neighbouring surfaces of the specimen, overall profile of the whole specimen can be measured by using the fringe scanning Fourier transform method. The method to determine step height from its surface profile is proposed.

Qinghua Wang, Hiroshi Tsuda, Satoshi Kishimoto, Yoshihisa Tanaka, Yutaka Kagawa
THREE MOIRÉ TECHNIQUES UNDER A LASER SCANNING MICROSCOPE FOR MICRON/SUBMICRON-SCALE DEFORMATION MEASUREMENT

Three Moiré techniques based on a laser scanning microscope (LSM) were presented and compared for the first time, including the LSM scanning moiré method, our developed LSM overlapping moiré method, and our newly developed LSM secondary moiré method. The formation principles of these moiré patterns and the measurement principles for deformation measurement were introduced. The applicable conditions of these three techniques were analyzed. Some typical moiré fringes on a strain gauge, carbon fiber reinforce plastics, a polyimide film and a silicon wafer were illustrated. Our developed LSM overlapping moiré method and secondary moiré method are effective in eliminating the scanning distortion of the LSM. These three kinds of moiré techniques are able to expand the application range of the LSM in deformation measurement at the micron and the submicron scales.

Pierre Otal, Jean-Claude Legras
Three technologies met in the absolute pressure range 0,5 Pa to 3 Pa

The LNE standards around 1 Pa absolute are constituted by a force-balanced piston gauge (FPG), 100 Pa capacitance diaphragm gauges (CDGs), and spinning rotor gauges (SRGs). The key parameters limiting the performance of the devices are presented. The results of a comparison involving at the same time the three instruments are presented and discussed, as well as the capabilities of these instruments in this range. As an example, the repeatability of measurements, and the linearity error in the comparison are less than 2 mPa.

Chenguang Cai, Zhihua Liu, Ming Yang
Three-Component Primary Vibration Calibration System at NIM

A three-component primary vibration calibration system had been set up in National Institute of Metrology, which consists of an air bearing three- component shaker, a sinusoidal three-component control system and a primary three-component vibration measuring system. A motion coupling device based on air bearing force transferring and motion guiding has been developed to simultaneously generate three-component vibration in the three orthogonal coordinates. The rectilinear, circular, and elliptical space motions have been realized by the sinusoidal three-component control algorithm. The three-component measuring system can simultaneously measure the three orthogonal motion quantities based on sine-approximation method.

Page 785 of 851 Results 7841 - 7850 of 8504