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Hans Peter Grieneisen, Aline S.P.Timmins, André S. Sardinha, Iakyra B. Couceiro
ILLUMINANCE MEASUREMENTS OF ROADWAYS

The aim of this paper is to present the first initiatives of the photometric group at Inmetro to analyze and test measurement procedures of lighting performance of roadways. At present, the evaluation for the average illuminance follows the brazilian standard ABNT-NBR-5101. The illuminance values measured in the field test are compared with calculated values, using the intensity distribution of the luminaires, which have been measured with a goniophotometer. Close agreement is found.

S. Patzelt, F. Horn, G. Goch
FAST INTEGRAL OPTICAL ROUGHNESS MEASUREMENT OF SPECULAR REFLECTING SURFACES IN THE NANOMETER RANGE

A fast optical roughness measuring device with a compact design is presented. The measuring principle is based on double scattering of coherent light. The measurement results in an integral statistical roughness value like Ra or Rq according to ISO 4287. It is valid for the illuminated surface area with diameters between 0.5 mm and 10 mm at a resolution of about 1 nm (Ra-value). A simulation model of the optical roughness measuring process based on the Huygens-Fresnel approximation was implemented. The simulation tool enables to investigate potential improvements of the measuring method without expensive and time consuming experiments.

Eugen-Georg Woschni
DEVELOPMENTS OF MEASUREMENT DUE TO TENDENCIES OF MICROELECTRONICS AND A NEW OPTIMIZATION CRITERION

The paper deals with problems of dynamic behaviour and shows especially how the development of microelectronics influences this field and how to teach this trends applying also heuristic methods and approximations. Using the results of information theory a new optimization criterion is introduced.

Klaus Körner, Evangelos Papastathopoulos, Wolfgang Osten
SOME ASPECTS OF CHROMATIC CONFOCAL SPECTRAL INTERFEROMETRY

In this paper, we report on the recent development of a novel low coherence interferometry technique for the purpose of 3D-topography measurements. It combines the well established techniques of spectral-interferometry (SI) and chromatic-confocal microscopy (CCM). It allows for the detection of an object’s depth position, without the necessity of a mechanical axial-scan, and the measurement is performed in a so-called “single-shot” manner. Focusing the white-light with a microscope objective combined with a diffractive optical element leads to an expansion of the axial-range of the sensor beyond the depth-of-focus, limited by the numerical aperture (NA) of the used objective. Confocally filtering the object’s light causes the reduction of the lateral dimension of the area sampled upon the object. Due to the high NA, a high light collection-efficiency is achieved as well. The attained interferometric signals consist of high-contrast wavelets in the optical-frequency domain. The depth position of an investigated point of the object is given by the modulation-period of the wavelets. Therefore, unlike in CCM, position-wavelength referencing is not necessary.

Robert Schmitt, Tilo Pfeifer, Alexandre Orth
FEASIBLE PRODUCTION OF FIBRE-REINFORCED COMPOSITES THROUGH INLINE INSPECTION WITH MACHINE VISION

The application of Fibre-Reinforced Plastics is important in many engineering areas, but vital for the aerospace industry. This work shows how inline metrology can contribute to a feasible production of composite parts. An inspection system based on a Machine Vision System will be presented as a key-component for the automatic construction of complex Preform structures.

Hiroaki Nishioka, Satoru Takahashi, Kiyoshi Takamasu
A SUPER-RESOLUTION MICROSCOPY WITH STANDING EVANESCENT LIGHT AND IMAGE RECONSTRUCTION METHOD

We propose a super-resolution microscopy that employs standing evanescent light illumination and image reconstruction method with successive approximation. Samples are illuminated with standing evanescent light, which is formed and shifted into different positions on the interface of total internal reflection (TIR). Scattering light emitted from the illuminated samples is detected through far-field imaging optics. We assume two hypotheses of linearity and incoherence about the scattering light. Then we reconstruct the sample distribution from scattering images and standing evanescent light intensity with successive approximation. We examined this microscopy with one-dimensional computer simulation and demonstrated that super resolution over the diffraction limit is achievable. The resolution power improves with shorter peak-to-peak distance of standing evanescent light and more cycles of the reconstruction calculation. As a possible resolution, two dot samples separated by 50 nm were resolved when the wavelength is 633 nm and the diffraction limit is 594 nm. With two-dimensional computer simulation, we were also able to resolve random dot samples in super resolution by using longitudinal and transversal standing evanescent light.

Toshie Yoshioka, Takashi Miyoshi, Yasuhiro Takaya
MEASUREMENT OF PATTERNED WAFER SURFACE DEFECTS USING ANNULAR EVANESCENT LIGHT ILLUMINATION METHOD

To detect particulate defects on patterned wafers of below 100 nm design rule, we proposed a new detection method using evanescent light illumination. To verify the feasibility of the method, we performed fundamental experiments. The results show that particle with a size of 170 nm on the patterned wafer surface with about 400 nm pitch is detected.

Salvador Echeverría-Villagómez, Mahdha Flores-Campos, Rita Pantoja-Lesso, Nadira Rodríguez-Damián, Benito Valgañón-Argueta
HUMAN RESOURCE AND KNOWLEDGE MANAGEMENT SYSTEM FOR COMPETENCES IN METROLOGY USING INFORMATION TECHNOLOGIES

This article presents a proposal for the development of a Knowledge management system for the management of Metrologic knowledge. It was conceived to solve the problematic detected at some metrological organizations in México. It shows the revision of some information about HR problems, Knowledge management and Technology of education tendencies. The system is under development in the time this paper was written, however it is considered pertinent to present this information as a strategy that could be adopted by any organization concerned with metrology and on the other hand it expected to be improved with the comments of other NMIs (National Measurement Institutes) experiences.

Queenie Siu Hang Chui, Jaim Lichtig
ASSESSING UNCERTAINTIES RELATED TO LINEAR CALIBRATION CURVES: A CASE STUDY FOR FLAME ATOMIC ABSORPTION SPECTROMETRY

Least square linear regression is widely used in analytical chemistry. In practice a linear relationship between substance content and measured value still has been assumed based on the correlation coefficient criterion, although not recommended. Textbooks provide the necessary formulas for the fitting process, based on the assumption that there is no error in the independent variable. In practice the ordinary least squares (OLS) textbook procedure is used even when the previously stated assumptions are not strictly fulfilled. In this paper, how to validate the calibration function is dealt with in detail using as an example based on measurements obtained for cadmium determination by flame atomic absorption spectrophotometry (FAAS). Assessing uncertainties related to linear calibration curves is also discussed. Considering uncertainties of weights and volumetric equipment and instrumental analytical signal it is observed that the most important factor that contributes to the final uncertainty is the uncertainty of the calibration function.

Dilhermando Augusto de Mello, Luciana A. Almeida Carvalho
"IT IS NOT FORBIDDEN TO DREAM… NOR TO COUNT TALES" METROLOGY EDUCATION FOR THE YOUTH

XVIII IMEKO World Congress presents the paper METROLOGY EDUCATION FOR THE YOUTH. The work addresses among one forms playful to present the metrology fundamentals and the main scientists who contributed with their discoveries, research and measurements, throughout the evolution of the human being and the technology.

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