Wyniki wyszukiwania - BazTech

1

Comparative analysis of interferogram noise filtration using wavelet transform and spin filtering algorithms

Zielinski B., Patorski K.

Opto-Electronics Review

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2010

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Vol. 18, No. 2

155-162

EN

The aim of this paper is to analyze 2D fringe pattern denoising performed by two chosen methods based on quasi-1D two-arm spin filter and 2D discrete wavelet transform (DWT) signal decomposition and thresholding. The ultimate aim of this comparison is to estimate which algorithm is better suited for high-accuracy measurements by phase shifting interferometry (PSI) with the phase step evaluation using the lattice site approach. The spin filtering method proposed by Yu et al. (1994) was designed to minimize possible fringe blur and distortion. The 2D DWT also presents such features due to a lossless nature of the signal wavelet decomposition. To compare both methods, a special 2D histogram introduced by Gutman and Weber (1998) is used to evaluate intensity errors introduced by each of the presented algorithms.

2

Phase-shifting interferometry for microelement vibration studies : systematic error analysis and experimental corroboration

Patorski K., Sienicki Z., Styk A.

Elektronika : konstrukcje, technologie, zastosowania

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2004

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Vol. 45, nr 8-9

281-284

EN

Vibration testing of silicone microelements using two-beam interferometric microscopy with time-averaging and the temporal phase shifting (TPS) method for automatic analysis of interferograms is investigated. The information on the sinusoidal vibration amplitude encoded in the changes of the contrast or intensity modulation of interference fringes is aimed at. The influence of experimental errors related to recording component TPS frames on the retrieved zero order Bessel function is studied numerically and experimentally.

PL

Praca dotyczy badania drgań mikroelementów krzemowych metodą mikroskopii interferencyjnej z uśrednianiem w czasie i automatyczną analizą interferogramów metodą czasowej dyskretnej zmiany fazy. Celem analizy jest informacja o rozkładzie amplitudy sinusoidalnych drgań zakodowana w postaci zmian kontrastu lub modulacji intensywności prążków interferencyjnych. W pracy zamieszczono analizę numeryczną i doświadczalną wpływu błędów rejestracji interferogramów składowych na odtwarzaną funkcję Bessela zerowego rzędu.

3

Automatic polarimetric system for early medical diagnosis by biotissue testing

Jóźwicki R., Patorski K., Angelsky O.V., Ushenko A.G., Burkovets D.N., Ushenko Y.A.

Optica Applicata

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2002

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Vol. 32, nr 4

603-612

EN

An automatic polarimetric system constructed at the Optical Engineering Division of the Warsaw University of Technology (Poland) and the evaluation method developed at the Department of Correlation Optics of Chernivtsi State University (Ukraine) are presented. The polarimeter has been designed and constructed to test the biotissues in the form of biopsy samples. After the system autocalibration the isocline and isochrome images are registered automatically. Correlation characteristics of the images calculated by the computer program provide the basis for formulating the medical diagnosis.

4

Fast contour tracing algorithm

Kozłowski J., Patorski K.

Optica Applicata

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2001

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Vol. 31, nr 3

611-618

EN

A simple and fast algorithm for contour tracing in two-level BitMap image is presented. The common comer of four neighbouring pixels, NODE, is defined as the basic element of the analysed structure. First the image is convoluted with 2*2 kernel which identifies all nodes, then the algorithm follows the line connecting contour nodes, and extracts coordinates of border pixels according to the initial conditions, i.e., to the defined connectivity type and contour rotation. The main parts of this procedure (written in C/sup ++/) and results obtained with the demonstration program KRATA, based on this algorithm, are presented.