V. Firago

ECTL application for carbon monoxide measurements

Semiconductor lasers, which can be surely characterize by many of their advantages, have been used for measurements of concentration of gases for many years. Doing measurements in industrial conditions, because of its several difficulties, needs using special technology of measurements. In this article using modified, correlated absorption spectroscopy, in order to measure CO concentration, has been shown.

High-temperature three-colour thermal imager

The influence of uncertainty of emissivity on the true temperature measurement errors is considered. Expressions for the optimal spectral range of thermal flux registration, that minimize an impact of uncertainty of emissivity, are obtained. Basic operation principles and parameters of high-temperature thermal imager based on 1/3-Inch Wide-VGA CMOS Digital Image Sensor MT9V034C12STC and notebook computer are described. In contrast to thermal imagers of Mikron 9103/9104 and PyroView series, thermal image registration is performed simultaneously in three overlapping regions of near-infrared spectrum. This allows to perform the emissivity evaluation and to reduce the error in determining the temperature that arises from the uncertainty of thermal emissivity coefficient. Streszczenie. W artykule omowiono wplyw niepewności wartości wspolczynnika promieniowania cieplnego  na bląd pomiaru rzeczywistej temperatury. Sformulowano wzory pozwalające na wybor zakresu widmowego optymalnego do rejestracji strumieni cieplnych, ktore minimalizują wplyw niepewności . Opisano podstawowe zasady dzialania i parametry wysokotemperaturowej kamery termowizyjnej na bazie 1/3-Inch Wide-VGA CMOS Digital Image Sensor MT9V034C12STC i laptopa. W przeciwienstwie do wysokotemperaturowych kamer termowizyjnych serii Mikron 9103/9104 i PyroView rejestracja obrazu termicznego jest przeprowadzana jednocześnie w trzech nakladających sie cześciach widma bliskiej podczerwieni, co pozwala oszacowac  i zmniejszyc bląd wyznaczenia temperatury wynikający z niepewności wspolczynnika promieniowania cieplnego (Wysokotemperaturowa trojkolorowa kamera termowizyjna).

Determination of CO concentration using the modified laser correlation method

In the paper, the modified correlation method is presented as well as results of CO concentration measurements in laboratory conditions using this method. Measurements were obtained for high CO concentrations (exceeding 50%) and short optical path (1 and 2m long). The measurements can be treated as a reference for measurements for far low concentrations and longer optical paths. Some simulation results also has been presented showing influence of temperature and pressure on measurement accuracy.

Determination of blood flow velocity in vessels of the bulbar conjunctiva

The paper presents the methods and the system for registration of digital video recordings of the sclera with a spatial resolution of 2 μm. The pulsed illumination of the sclera was used to eliminate the image blurring caused by the continuous movement of the eyes. At evaluation of blood flow velocity the stabilization of the position of recorded images relatively to the first image frame is used and the trajectory of displacement of the bulbar conjunctiva of the eye is determined. Streszczenie. W artykule omówiono metody oraz opisano system do rejestracji cyfrowych nagrań wideo twardówki z rozdzielczością przestrzenną 2 μm. Zastosowano impulsowe oświetlenie twardówki w celu eliminacji rozmycia obrazu spowodowanego przez ciągły ruch gałek ocznych. Przy ocenie szybkości przepływu krwi przeprowadza się stabilizację pozycji zarejestrowanych obrazów względem pierwszej ramki obrazu oraz wyznacza się trajektorię przemieszczenia spojówki gałki ocznej. (Wyznaczenie szybkości przepływu krwi w naczyniach spojówki gałki ocznej).

The principles of reducing temperature measurement uncertainty of modern thermal imaging system

The aim of the present study is to investigate the reasons of temperature measurement uncertainty when using modern thermal imaging systems. The basic requirements for high-temperature thermal imaging technique, that can improve the accuracy of determining the temperature of the heated body, are formulated. Streszczenie. Celem niniejszej pracy jest badanie przyczyn niepewności pomiaru temperatury przy użyciu nowoczesnych systemów termowizyjnych. Sformułowano podstawowe wymagania dotyczące techniki obrazowania termicznego w zakresie wysokich temperatur, spełnienie których poprawi dokładność pomiaru temperatury ogrzewanego ciała. (Zasady zmniejszenia niedokładności pomiaru we współczesnym systemie termowizyjnym)

Spectral measurements of carbon monoxide

The work will present results of laboratory investigation of optoelectronic detector of carbon monoxide that uses an external cavity semiconductor laser turned within 1,5 and 1,6 μm. Measurement set-up incorporates cells 1 m and 2 m long containing the measured gas at variable concentration. Such set-up reflects the product of partial pressure and path length that can be found inside the power boiler.

Analyzer of CO concentration in the near wall layer of power boilers: concept and results of initial research

Operation of combustion process in power boilers in such a way that pollution standards are met and corrosion is limited requires continuous measurement of concentration of selected gases in the near wall layer of power boilers. The absorption spectroscopy is one of methods that allow such measurement. Specificity of the medium in which the measurement is to be made (among other things: high temperature, difficulties in installation of sources and detectors) requires utilization of optical fiber technology. Absorption spectra overlapping in the medium infrared range is an additional hindrance which makes application of special measurement algorithms necessary. A concept of structure of optoelectronic analyzer of CO concentration in the near wall layer of power boilers has been presented. The analyzer is based on modified correlation absorption spectroscopy within the range between 1557 nm and 1600 nm. Simulation results have been presented as well.

Estimation of coordinates of the center of narrow radiation beam with CCD array at a poor signal/noise ratio

Methods of determination of coordinates of the center of a narrow radiation beam by means of the CCD array are considered. For the continuous representation of images and noises the analytical expressions describing signal and noise functions at the output of optimal spatial filter are obtained, as well as the dispersion of optimal estimation of a position of Gaussian radiation beam. It is shown that using the CCD array the minimum error of estimation of the Gaussian beam position is observed when the beam effective diameter is approximately equal to 0.8 of lateral length of a light-sensitive cell of the array.