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  1. 7 Opto-Electronics Review
  2. 3 Bulletin of the Polish Academy of Sciences. Chemistry
  3. 3 Elektronika : konstrukcje, technologie, zastosowania
  4. 3 Optica Applicata
  5. 2 Przegląd Elektrotechniczny
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  1. 8 Bielecki Z.
  2. 7 Wojtas J.
  3. 6 Stacewicz T.
  4. 5 Mikołajczyk J.
  5. 3 Magryta P.
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  1. 1 2018
  2. 1 2017
  3. 3 2016
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  5. 2 2013
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1
Content available remote Frequency-multiplexed gas sensing using chirped laser molecular spectroscopy
Tomaszewska D., Jaworski P., Nikodem M.
Opto-Electronics Review
|
2018
|
Vol. 26, No. 2
103--107
EN
A method for frequency-multiplexed multi-sample gas sensing is presented. It enables measuring multiple samples placed simultaneously in the setup, without any optical or mechanical switching. Samples are measured using heterodyne detection and signal from each sensing path is encoded at different carrier frequency. Subsequently, a signal from particular sample is retrieved through heterodyne beatnote demodulation at unique frequency. This technique is particularly suitable for real-time calibration of the sensor through a sequential (or simultaneous) detection of three signals: from unknown sample, reference sample and baseline. Basic setup is demonstrated and proof-of-concept experiments are presented. Very good agreement with spectra measured using standard tunable diode absorption spectroscopy is obtained.
2
Content available remote Highly-efficient fully-fiberized mid-infrared differential frequency generation source and its application to laser spectroscopy
Krzempek K., Dudzik G., Hudzikowski A., Gluszek A., Abramski K.
Opto-Electronics Review
|
2017
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Vol. 25, No. 4
269--274
EN
Widely-tunable, fully-monolithic, mid-infrared (mid-IR) deference frequency generation source (DFG) is presented. By using a custom designed fiber-pigtailed periodically poled lithium niobate (PPLN) crystal module the idler beam was generated with an efficiency of 21%/W, yielding 2.6 mW of optical output power. The proposed all-fiber configuration radically simplified the optical frequency conversion setup, making it robust and easily configurable. The usefulness of the constructed source was verified by performing simultaneous wavelength modulation spectroscopy (WMS) laser trace gas detection of methane, near 2999 cm⁻¹, and ethane, near 2997 cm⁻¹, via two independently generated, tunable idler beams.
3
Content available remote Detection of disease markers in human breath with laser absorption spectroscopy
Stacewicz T., Bielecki Z., Wojtas J., Magryta P., Mikolajczyk J., Szabra D.
Opto-Electronics Review
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2016
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Vol. 24, No. 2
82--94
EN
Number of trace compounds (called biomarkers), which occur in human breath, provide an information about individual feature of the body, as well as on the state of its health. In this paper we present the results of experiments about detection of certain biomarkers using laser absorption spectroscopy methods of high sensitivity. For NO, OCS, C₂H₆, NH₃, CH₄, CO and CO(CH₃)₂ an analysis of the absorption spectra was performed. The influence of interferents contained in exhaled air was considered. Optimal wavelengths of the detection were found and the solutions of the sensors, as well as the obtained results were presented. For majority of the compounds mentioned above the detection limits applicable for medicine were achieved. The experiments showed that the selected optoelectronic techniques can be applied for screening devices providing early diseases detection.
4
Content available Fast optoelectronic sensor of water concentration
Nowak J. L., Magryta P., Stacewicz T., Kumala W., Malinowski S. P.
Optica Applicata
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2016
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Vol. 46, nr 4
607--618
EN
A prototype optoelectronic hygrometer, based on absorption of laser light tuned to a specific rovibronic absorption line of H2O at 1364.68961 nm is described. Target application is meteorology, in particular precise and fast measurements of small-scale humidity fluctuations in turbulent atmospheric flows. Tests of the prototype instrument performed in the atmospheric boundary layer have proven the advantage of this optoelectronic sensor over typical, commercially available UV hygrometers designed for similar applications.
5
Multipleksacja i demultipleksacja sygnałów optycznych do celów spektroskopii
Stacewicz T., Magryta P., Bielecki Z., Wojtas J.
Elektronika : konstrukcje, technologie, zastosowania
|
2016
|
Vol. 57, nr 9
70--72
PL
W artykule przedstawiono metodę multipleksacji wiązek laserowych w jeden strumień promieniowania oraz sposób rozdzielania informacji niesionych przez taką wiązkę, po przejściu przez układ spektroskopowy. Opisano czujnik do spektroskopii wieloprzejściowej do jednoczesnego wykrywania kilku substancji gazowych z wykorzystaniem tego rozwiązania. Zbadano także stabilność parametrów skonstruowanego systemu.
EN
The paper presents multiplexation optical signals consisting on combining of modulated laser beams and the retrieving of the information that is carried by the beams after their passing through a spectroscopy system. Phase sensitive detection is applied. The method was applied for simultaneous detection of several gas components with multipass cell. Results of investigation of stability and sensitivity of the system are shown as well.
6
Układy zasilania i sterowania kwantowych laserów kaskadowych
Szabra D., Mikołajczyk J., Bielecki Z., Pierściński K., Pierścińska D., Bugajski M.
Elektronika : konstrukcje, technologie, zastosowania
|
2014
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Vol. 55, nr 11
50-53
PL
W pracy przedstawiono istotne zagadnienia związane z praktycznym zastosowaniem laserów kaskadowych w układach spektroskopii absorpcyjnej (ang. Laser Absorption Spectroscopy – LAS). Dotyczą one głównie aspektów sterowania ich parametrami w poszczególnych metodach LAS. W praktyce, każda z tych metod narzuca odpowiedni tryb pracy lasera, który jednocześnie generuje potrzebę opracowania dedykowanego układu sygnałów sterujących. Przeprowadzono analizy pracy i badania przykładowych układów zasilania i sterowania laserów kaskadowych. Szczególną uwagę zwrócono na problemy związane z zastosowaniem laserów w układach spektroskopii strat we wnęce optycznej.
EN
The paper presents some issues related to application of quantum cascade laser (QCL) in laser absorption spectroscopy (LAS). The main aspects of QCL control parameters in different LAS methods are disscussed. In practice, these methods influence on desired operating mode of the laser. The requirementas simultaneously generate the specific need for a laser driving signals. Some systems to control QCL were also analyzed and studied. Particular attention was paid to the problems associated with laser pulse driving in cavity enhanced spectroscopy systems.
7
Content available remote Układy sterowania laserami kaskadowymi
Bielecki Z., Szabra D., Nowakowski M., Mikołajczyk J., Wojtas J.
Przegląd Elektrotechniczny
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2013
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R. 89, nr 10
43-46
PL
W pracy przedstawiono układy sterowania laserami kaskadowymi (quantum cascade lasers – QCL) pod kątem ich zastosowania w dwóch technikach; spektroskopii strat we wnęce optycznej oraz spektroskopii wieloprzejściowej. W trakcie projektowania tych sterowników, szczególną uwagę zwrócono zarówno na parametry czasowo-energetyczne wytwarzanych sygnałów, oraz na możliwości zastosowania dwóch technik przestrajania promieniowania laserowego tzn. wewnątrzimpulsowej lub międzyimpulsowej. Przeprowadzono również wstępne badania, które umożliwiły określenie właściwości tych układów oraz dały podstawę do opracowania kompaktowych sterowników laserów QCL.
EN
Quantum cascade laser drivers for absorption spectroscopy - the paper presents the fundamental aspects of optical spectroscopy using quantum cascade lasers. Two driving systems were described in terms of both QCL research and QCL applications in cavity ring down and multipass techniques. During drivers designing, the particular attention was given not only to energy-time parameters range (power, frequency, pulse duration, rise time). There were also adapted so-called spectral tuning techniques, i.e. intrapulse or interpulse wavelength modulation. Preliminary studies gave the possibility to determine the properties of designed drivers.
8
Content available remote Towards optoelectronic detection of explosives
Wojtas J., Stacewicz T., Bielecki Z., Rutecka B., Medrzycki R., Mikolajczyk J.
Opto-Electronics Review
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2013
|
Vol. 21, No. 2
210-219
EN
Detection of explosives is an important challenge for contemporary science and technology of security systems. We present an application of NOx sensors equipped with concentrator in searching of explosives. The sensors using CRDS with blue - violet diode lasers (410 nm) as well as with QCL lasers (5.26 µm and 4.53 µm) are described. The detection method is based either on reaction of the sensors to the nitrogen oxides emitted by explosives or to NOx produced during thermal decomposition of explosive vapours. For TNT, PETN, RDX, and HMX the detection limit better than 1 ng has been achieved.
9
Content available Evaluation of laser cleaning progress and quality
Koss A., Marczak J.
Wiadomości Konserwatorskie
|
2012
|
Nr 32
109-114
EN
The estimation and analysis of damages (present condition), object conservation (cleaning process), and the protection of an object against further degradation are the main tasks of conservator. One of the physical methods that is becoming more and more popular for unwanted deposit removal is the laser cleaning method. Laser tool is non-contact, selective, local, controlled, self-limiting, gives immediate feedback and preserves even the gentlest of relief - the trace of a paintbrush. Paper presents application of different, selected physical methods to characterize condition of works of art as well as laser cleaning process itself. It includes, tested in our laboratories, optical surface measurements (e.g. colourimetry, interferometry), thermography, and acoustic measurements for "on-line" evaluation of cleaning progress. Results of laser Raman spectrometry analyses will illustrate identification of objects superficial layers.
PL
Ocena i analiza uszkodzeń (stanu aktualnego) oraz obiektu poddanego konserwacji (np. w procesie czyszczenia) i zabezpieczenie obiektu przed dalszą degradacją stanowią główne zadania konserwatora. Jedną z metod fizycznych, którą staje się coraz powszechniej w usuwaniu niepożądanych nawarstwień, jest metoda z wykorzystaniem promieniowania laserowego (metoda laserowa). Laser, jako narzędzie konserwatorskie jest: bezkontaktowe, selektywne, lokalnie kontrolowane, samo się ograniczające, dające natychmiastowe sprzężenie zwrotne i zachowujące nawet najdelikatniejszy relief - zachowujące ślady pędzla artysty malarza. W artykule przedstawia się zastosowanie różnych, wybranych metod fizycznych, aby scharakteryzować aktualny stan dzieła sztuki, jak również sam proces czyszczenia laserowego. Artykuł zawiera opis przeprowadzonych testów w laboratoriach, pomiary optyczne powierzchni (np. kolorymetryczne, interferometryczne), termowizyjne i akustyczne, w celu oceny procesu czyszczenia laserowego "on line". Przedstawiono ponadto przykłady analizy warstw wierzchnich z wykorzystaniem spektrometru Ramana.
10
Content available remote Bramka do wykrywania materiałów wybuchowych
Wawer J., Wojtas J., Mędrzycki R., Mikołajczyk J., Bielecki Z., Dąbrowski T.
Przegląd Elektrotechniczny
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2012
|
R. 88, nr 11b
29-31
PL
W artykule przedstawiono projekt i badania eksperymentalne bramki bezpieczeństwa umożliwiającej wykrywanie par wybranych materiałów wybuchowych. W tym celu opracowano optoelektroniczny sensor ditlenku azotu, w którym zastosowano metodę spektroskopii strat we wnęce optycznej, zaliczanej do metod o najwyższej czułości. Badania wstępne wykazały, że prezentowana bramka może być stosowana do kontroli wejść w strategicznych obiektach wojskowych oraz użyteczności publicznej, szczególnie o dużym nasileniu ruchu, takich jak lotniska, porty, dworce, stacje metra, itp.
EN
The paper presents a project and investigations of a security portal with explosives sensor . In the portal, an optoelectronic NO2 sensor operating on basis of Cavity Enhanced Absorption Spectroscopy (CEAS) is applied. CEAS technique is one of the most sensitive detection methods. The presented portal is likely to become a very effective tool for explosives detection. That is why, it could be used to control entries of important objects e.g. airports, government buildings, skyscrapers, military bases, and so on.
11
Content available remote Ultrasensitive laser spectroscopy for breath analysis
Wojtas J., Bielecki Z., Stacewicz T., Mikołajczyk J., Nowakowski M.
Opto-Electronics Review
|
2012
|
Vol. 20, No. 1
26-39
EN
At present there are many reasons for seeking new methods and technologies that aim to develop new and more perfect sensors for different chemical compounds. However, the main reasons are safety ensuring and health care. In the paper, recent advances in the human breath analysis by the use of different techniques are presented. We have selected non-invasive ones ensuring detection of pathogenic changes at a molecular level. The presence of certain molecules in the human breath is used as an indicator of a specific disease. Thus, the analysis of the human breath is very useful for health monitoring. We have shown some examples of diseases' biomarkers and various methods capable of detecting them. Described methods have been divided into non-optical and optical methods. The former ones are the following: gas chromatography, flame ionization detection, mass spectrometry, ion mobility spectrometry, proton transfer reaction mass spectrometry, selected ion flow tube mass spectrometry. In recent twenty years, the optical methods have become more popular, especially the laser techniques. They have a great potential for detection and monitoring of the components in the gas phase. These methods are characterized by high sensitivity and good selectivity. The spectroscopic sensors provide the opportunity to detect specific gases and to measure their concentration either in a sampling place or a remote one. Multipass spectroscopy, cavity ring-down spectroscopy, and photo-acoustic spectroscopy were characterised in the paper as well.
12
Content available remote Cavity ring down spectroscopy : detection of trace amounts of substance
Stacewicz T., Wojtas J., Bielecki Z., Nowakowski M., Mikołajczyk J., Mędrzycki R., Rutecka B.
Opto-Electronics Review
|
2012
|
Vol. 20, No. 1
53-60
EN
We describe several applications of cavity ring-down spectroscopy (CRDS) for trace matter detection. NO₂ sensor was constructed in our team using this technique and blue-violet lasers (395–440 nm). Its sensitivity is better than single ppb. CRDS at 627 nm was used for detection of NO₃. Successful monitoring of N₂O in air requires high precision mid-infrared spectroscopy. These sensors might be used for atmospheric purity monitoring as well as for explosives detection. Here, the spectroscopy on sharp vibronic molecular resonances is performed. Therefore the single mode lasers which can be tuned to selected molecular lines are used. Similarly, the spectroscopy at 936 nm was used for sensitive water vapour detection. The opportunity of construction of H₂O sensor reaching the sensitivity about 10 ppb is also discussed.
13
Content available Precision spectroscopy of cold strontium atoms, towards optical atomic clock
Bober M., Zachorowski J., Gawlik W., Morzyński P., Zawada M., Lisak D., Cygan A., Bielska K., Piwiński M., Trawiński R., Ciuryło R., Ozimek F., Radzewicz C.
Bulletin of the Polish Academy of Sciences. Technical Sciences
|
2012
|
Vol. 60, nr 4
707-710
EN
This report concerns the experiment of precision spectroscopy of cold strontium atoms in the Polish National Laboratory of Atomic, Molecular and Optical Physics in Toruń. The system is composed of a Zeeman slower and magneto-optical traps (at 461 nm and 689 nm), a frequency comb, and a narrow-band laser locked to an ultra-stable optical cavity. All parts of the experiment are prepared and the first measurements of the absolute frequency of the 1S0-3P1, 689 nm optical transition in 88Sr atoms are performed.
14
Content available remote Laser Photoacoustic Spectroscopy of the Piezoceramic Materials
Mityurich G. S., Aleksiejuk M., Astakhov P. V., Serdyukov A. N.
Archives of Metallurgy and Materials
|
2009
|
Vol. 54, iss. 4
889-894
EN
The aim of the work is the investigation of photoacoustic transformation in piezoceramic materials and piezocrystals of various classes of symmetry. It is considered the case thermal mechanism of excitation of thermoelastic waves by various Bessel light beams polarization modes. Within the range of modulation frequency 100kHz- 1MHz the resonance phenomena are found. It’s showed that the amplitude of the resonance curves substantially depends on the radial distribution of the velocity of the Bessel light beams energy dissipation, on the type of polarization modes and on the geometric dimensions of the piezoelectric crystal, which acts also as a piezodetector. We can state that the results obtained by the resonance photoacoustic transformation can be used to improve the resolution of methods of photoacoustic spectroscopy and microscopy.
PL
Celem pracy są badania nad fotoakustyczną transformacją w materiałach piezoceramicznych oraz piezokryształach o różnych klasach symetrii. W pracy rozpatrywano termiczny mechanizm wzbudzania termosprężystych fal przez różne mody polaryzacyjne wiązek Bessela. W zakresie częstotliwości modulacji 100kHz-1MHz obserwowano zjawiska rezonansu. Wykazano, iż amplituda krzywych rezonansu w znacznym stopniu zależy od radialnego rozdziału prędkości rozpraszania energii wiązek Bessela, od typu modów polaryzacyjnych oraz od wymiarów geometrycznych kryształu piezoelektrycznego, który pełni także funkcje piezodetektora.
15
Komputerowy system kontroli eksperymentu i akwizycji sygnałów spektroskopowych
Buczek A., Szawioła G., Stachowska E., Koczorowski W., Walaszyk A., Stefańska D., Jarosz A., Furmann B.
Elektronika : konstrukcje, technologie, zastosowania
|
2008
|
Vol. 49, nr 6
193-195
PL
W artykule przedstawiono uniwersalny komputerowy system pomiarowy przeznaczony do spektroskopowych badań właściwości materii. Zastosowane w nim procedury pomiarowe i algorytmy mogą służyć do konstrukcji sensorów pomiarowych wykorzystujących fizyczne efekty kwantowe.
EN
We present an universal measurement system for spectroscopic investigations. Procedures and algorithms included may serve in the construction of sensors based on quantum effects.
16
Content available remote The 61Π u state of Na2 molecule
Grochola A., Kubkowska M. K., Jastrzębski W., Kowalczyk P.
Optica Applicata
|
2006
|
Vol. 36, nr 4
s. 469--473
EN
Excitation spectra of sodium dimer were analysed within the range 34200–36400 cm–1. The experiment was done using polarisation labelling spectroscopy technique. In the spectral region under investigation we found several vibrational progressions belonging to a single band system having the ground state of Na2 as the lower state. The upper state was of 1Π u symmetry as indicated by the presence of Q lines in the spectrum and basing on theoretical calculations it was identified as the 61Π u (3s+4f ) state. The Dunham coefficients and potential curve characterising this state were deduced from the observed spectra.
17
Content available remote Investigation of a highly excited electronic 1Π state of NaLi molecule
Bang N. H., Grochola A., Jastrzebski W., Kowalczyk P., Salami H.
Optica Applicata
|
2006
|
Vol. 36, nr 4
s. 499--504
EN
We report on our investigation of the excitation spectra of the NaLi molecule in the energy range 31000–33900 cm–1. A polarisation labelling technique is used to ensure rotational resolution of the spectra and to enable unambiguous assignment of the NaLi transitions. A hitherto unknown electronic state of 1Π symmetry is observed. Major molecular constants of the state are determined and its potential curve constructed using the inverted perturbation approach method.
18
Content available remote Application of high-accuracy time-resolved laser spectroscopy to the study of diffusion-controlled triplet-triplet annihilation
Borowicz P., Nickel B.
Opto-Electronics Review
|
2004
|
Vol. 12, No. 3
325-332
EN
The kinetics of the diffusion-controlled triplet-triplet annihilation of anthracene was investigated with the time-resolved laser spectroscopy. The analysis of the decays of delayed fluorescence with the standard Smoluchowski model leads to an artificial dependence of the annihilation radius from the delay (starting point of evaluation). The intuitive-empirical modification of the so-called short-time term in Smoluchowski equation (based on the treatment of the triplet-triplet annihilation as a non-Fickian diffusion) is proposed. A brief comparison is presented between standard Smoluchowski and modified models for anthracene. The limits of the approximation used are discussed and the way of further progress is suggested.
19
Content available remote Photodynamic diagnosis of cancer using fluorescence or autofluorescence
Malini O.
Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna
|
2004
|
Vol. 10, nr 1-2
14-14
20
Motion of hydrogen bonds in liquid water: direct observation in real time
Bratos S., Gale G. M., Gallot G., Hache F., Lascoux N., Leicknam J-Cl.
Bulletin of the Polish Academy of Sciences. Chemistry
|
1999
|
Vol. 47, No. 4
273-281
EN
An experiment is described to study temporal variations of the hydrogen bond length in liquid water. The principles of this laser spectroscopic experiment are explained first. The construction of a laser source generating 150 fs pulses in the 2.5-4.4 um spectral region is detailed next. The theoretical analysis is proposed in terms of statistical mechanics of nonlinear optical processes. A new spectral effect is reported, the pump-probe delay dependent solvatochromic shift of the OH band. It is shown how this effect can be exploited to "photograph" the dynamics of the OH...O bonds in real time.
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