Jacek Wojtas

Jacek Wojtas
Military University of Technology | WAT · Institute of Optoelectronics

Associate Professor, BEng, PhD, DSc,

About

90
Publications
45,066
Reads
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965
Citations
Introduction
Jacek Wojtas currently works at the Institute of Optoelectronics, Military University of Technology. Jacek does research in Optoelectronic Engineering and Optical Metrology.
Additional affiliations
March 2003 - August 2020
Military University of Technology
Position
  • Professor
Description
  • His research focuses on optoelectronic gas sensors to monitor pollution, detect explosives and biomarkers of diseases in human breath. More than 230 publications, an associate editor in 3 JCR journal and reviewer in over 20 journals and grant agencies.

Publications

Publications (90)
Article
Full-text available
The review includes results of analyses and research aimed at standardizing the concepts and measurement procedures associated with photodetector parameters. Photodetectors are key components that ensure the conversion of incoming optical radiation into an electrical signal in a wide variety of sophisticated optoelectronic systems and everyday devi...
Article
Full-text available
Precision metrology is important for understanding and monitoring various phenomena, especially in special and scientific applications. The subject of the article covers selected aspects of the study of high-resolution measurements of the absorption spectra and their impact on practical issues. This research is crucial for the development of new sy...
Article
We report on the Ga-free InAs/InAsSb type-II superlattice (T2SL) based long wavelength infrared radiation (LWIR) methane (CH4) sensor operating at ~ 8 µm under thermoelectric (TE) cooling conditions. The presented device reaches detectivity (D*) ~ 2 × 10⁹ Jones ( ~ 8 µm), current responsivity (Ri) ~ 0.22 A/W, time constant (τ) ~ 14 ns. The CH4 dete...
Article
Full-text available
Thermally Enhanced Fourier-Transform Infrared Spectroscopy (TE-FTIR) is a new method applied to examination of thermal stability of energetic materials. Three melt-cast explosives: 2,4,6-trinitrotoluene (TNT); 2,4-dinitroanisole (DNAN) and propylnitroguanidine (PrNQ) were selected for testing. The obtained results revealed new facts about the stabi...
Article
Optoelectronic detection of disease biomarkers in air exhaled from human lungs
Article
Biomarkers are compounds whose excessive concentration in breath may indicate disease states. High precision laser absorption techniques, such as the multipass spectroscopy and cavity ring down spectroscopy at wavelengths corresponding to strong absorption lines of these compounds, are the appropriate methods for a sensitive detection of biomarkers...
Article
Full-text available
High precision and fast measurement of gas concentrations is important for both understanding and monitoring various phenomena, from industrial and environmental to medical and scientific applications. This article deals with the recent progress in ammonia detection using in-situ solid-state and optical methods. Due to the continuous progress in ma...
Article
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Fast-response optoelectronic detection of explosives' residues from the nitroaromatic compounds detonation: field studies approach, Measurement (2020), doi: https://doi. Abstract: We are presenting an application of optoelectronic nitrogen dioxide (NO 2) analyzer based on cavity enhanced absorption spectroscopy in the detection of traces of explosi...
Article
We present a promising approach to the electroanalytical detection of a specific nitroaromatic explosive in landfill leachates (LLs) that originated from a municipal solid waste plant. The paper is focused but not limited to the sensing of 4,4',5,5'-tetranitro-1H,1'H-2,2'-biimidazole (TNBI) using differential pulse voltammetry and cyclic voltammetr...
Article
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The study is devoted to the electrochemical detection of trace explosives on boron-doped diamond/graphene nanowall electrodes (B:DGNW). The electrodes were fabricated in a one-step growth process using chemical vapour deposition without any additional modifications. The electrochemical investigations were focused on the determination of the importa...
Article
Full-text available
Optoelectronic technology plays an important role in medical diagnosis. In the paper a review of some optoelectronic sensors for invasive and non-invasive human health test is presented. The main attention is paid on their basic operation principle and medical usefulness. The paper presents also own research related to developing of tools for human...
Article
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The article presents state of work in technology of free-space optical communications (Free Space Optics − FSO). Both commercially available optical data links and their further development are described. The main elements and operation limiting factors of FSO systems have been identified. Additionally, analyses of FSO/RF hybrid systems application...
Article
The application of compact inexpensive trace gas sensor technology to a mid-infrared nitric oxide (NO) detectoion using intracavity quartz-enhanced photoacoustic spectroscopy (I-QEPAS) is reported. A minimum detection limit of 4.8 ppbv within a 30 ms integration time was demonstrated by using a room-temperature, continuous-wave, distributed-feedbac...
Article
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Broadband, mid-infrared supercontinuum generation in a step-index fluoroindate fibre is reported. By using ~70-picosecond laser pulses at 2.02 μm, provided by an optical parametric generator, a wide spectrum with a cut-off wavelength at 5.25 μm and a 5-dB bandwidth covering the entire 2–5 μm spectral interval has been demonstrated for the first tim...
Conference Paper
A laboratory demonstrator of the optoelectronic sensor employing cavity enhanced spectroscopy has been designed to detect the trace amounts of carbon monoxide. High sensitivity of this sensor is provided by the use of optical cavity consisted of dielectric mirrors with extremely high reflectance. The instrument concept was taking into consideration...
Article
Full-text available
The paper describes an integrated laser absorption system as a potential tool for breath analysis for clinical diagnostics, online therapy monitoring and metabolic disorder control. The sensors operate basing on cavity enhanced spectroscopy and multi-pass spectroscopy supported by wavelength modulation spectroscopy. The aspects concerning selection...
Article
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,...
Article
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Sensing technology has been developed for detection of gases in some environmental, industrial, medical, and scientific applications. The main tasks of these works is to enhance performance of gas sensors taking into account their different applicability and scenarios of operation. This paper presents the descriptions, comparison and recent progres...
Conference Paper
Full-text available
A silicon integrated circuit is reported for radiating picosecond pulses with tunable repetition rate, covering frequencies from 0.03 to 1.03 THz. This source is used in a gas spectroscopy setup to measure the absorption lines of ammonia and water in the terahertz region.
Conference Paper
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Development of trace gas sensors based on mid-infrared interband cascade lasers, quantum cascade lasers as well as their applications will be reported. The sensor technology will use both laser absorption and quartz enhanced photoacoustic spectroscopy.
Article
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UNLABELLED: Great interest of scientific community is observed recently over non-invasive tests methods dedicated to diagnose disease states using biomarkers. The ability to detect these substances in the human breath can provide valuable information about disorder of biochemical processes in the body. Breath analysis is non-invasive, painless and...
Article
Full-text available
The paper presents one of the laser absorption spectroscopy techniques as an effective tool for sensitive analysis of trace gas species in human breath. Characterization of nitric oxide, carbonyl sulphide and ethane, and the selection of their absorption lines are described. Experiments with some biomarkers showed that detection of pathogenic chang...
Article
Full-text available
The potential of Quantum Cascade Laser technology has been recently harnessed in industry, medicine and military to create a range of original infrared gas sensors. These sensors have opened up many new applications due to compact size, excellent sensitivity, robust construction and low power requirements. They rely on infrared absorption spectrosc...
Article
Full-text available
Great interest of scientific community is observed recently over noninvasive tests methods dedicated to diagnose disease states using biomarkers. The ability to detect these substances in the human breath can provide valuable information about disorder of biochemical processes in the body. Breath analysis is non-invasive, painless and can provide a...
Article
Full-text available
Detection of explosives vapors is an extremely difficult task. The sensitivity of currently constructed detectors is often insufficient. The paper presents a description of an explosive vapors concentrator that improves the detection limit of some explosives detectors. These detectors have been developed at the Institute of Optoelectronics. The con...
Article
Full-text available
Abstract Detection of explosives vapors is an extremely difficult task. The sensitivity of currently constructed detectors is often insufficient. The paper presents a description of an explosive vapors concentrator that improves the detection limit of some explosives detectors. These detectors have been developed at the Institute of Optoelectronics...
Conference Paper
The aim of this paper is to address some of the aspects of thermal management of QCLs. Results include electrical and spectral characterization of the devices. Results show shift of QCL emission mode towards lower wavenumbers during the pulse. Characteristics were registered at different temperatures of operation and driving conditions. Registered...
Article
Full-text available
This paper describes two different optoelectronic detection techniques: cavity-enhanced absorption spectroscopy and photoacoustic spectroscopy. These techniques are designed to perform a sensitive analysis of trace gas species in exhaled human breath for medical applications. With such systems, the detection of pathogenic changes at the molecular l...
Conference Paper
Full-text available
Detection of trace amounts of substance is a challenging task in many technologies. Nowadays, a lot of detection systems operate at the detection limit. It is observed especially in such areas as medicine or security; for example, in explosive detection. In medicine, the technology of trace substance detection is associated with breath analysis. So...
Article
Full-text available
Breath is a rich mixture containing numerous volatile organic compounds at trace amounts (ppbv-pptv level) such as: hydrocarbons, alcohols, ketones, aldehydes, esters or heterocycles. The presence of some of them depends on health status. Therefore, breath analysis might be useful for clinical diagnostics, therapy monitoring and control of metaboli...
Article
Full-text available
Investigation of nitric oxide and nitrous oxide optoelectronic sensors is described. The detection of both components was done by measurement of absorption that occurs due to transition between vibronic molecular transitions. The improvement of the sensitivity was achieved due to application of cavity enhanced absorption spectroscopy. Two optical c...
Article
The paper presents a prototype of a driving system designed to laboratory investigations of quantum cascade lasers. Significant requirements of these lasers operation, as well as a construction of the main components of the system were analyzed. During the performed investigations, a tuning range of both current pulses and temperature control opera...
Article
The paper presents the possibility of using laser absorption spectroscopy in medical diagnostics. Some detection techniques of disease markers existed in exhaled air are described. There is also discussed performance of quantum cascade lasers (QCL's) in view of their applications in infrared spectroscopy. In the main part the work, some methods of...
Article
The article describes an application one of the most sensitive optoelectronic method - Cavity Enhanced Absorption Spectroscopy in investigation of nitric oxide in exhaled breath. Measurement of nitric oxide concentration in exhaled breath is a quantitative, non-invasive, simple, and safe method of respiratory inflammation and asthma diagnosis. For...
Article
Full-text available
This article presents design issues of high-sensitive laser absorption spectroscopy systems for nitrogen oxides (NOx) detection. Examples of our systems and their investigation results are also described. The constructed systems use one of the most sensitive methods, cavity enhanced absorption spectroscopy (CEAS). They operate at different waveleng...
Article
Full-text available
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 m...
Article
Full-text available
The article describes application of cavity enhanced absorption spectroscopy (CEAS) for detection of nitrogen oxides and vapours of explosives. The oxides are important greenhouse gases that are of large influence on environment, living organisms and human health. These compounds are also markers of some human diseases as well as they are emitted b...
Article
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...
Article
Full-text available
Optoelectronic system designed to biomarkers detection - the paper presents a design of the system, which provides early diagnosis of diseases based on the analysis of human breath. The goal of the undertaken work is to develope the optoelectronic system for the detection of volatile disease markers. In this design, there are used highly sensitive...
Article
The paper presents investigations of a free space optical transmitter operating with quantum cascade lasers. The main goal of the research was to determine influence of lasers driver parameters on an optical data link performance. Using some commercial driving devices, the laser pulse limitations of power, repetition rate and time duration have bee...
Article
Full-text available
The article describes an application of cavity enhanced absorption spectroscopy for nitric oxide and nitrous oxide detection. Both oxides are important greenhouse gases that are of large influence on environment, living organisms and human health. These compounds are also biomarkers of some human diseases. They determine the level of acid rain, and...
Article
The paper presents a model of a free space optical transmitter operating in the wavelength range of 8-12 μm. In the transmitter, a quantum cascade laser controlled by a special driver was applied. The driver provides the control of the energy, repetition rate and duration of radiation pulses. In the described transmitter, generation of pulses with...
Article
The paper presents a construction and some investigations results of a new driver for quantum cascade (QC) lasers. The driver is designed to control pulse and CW mode QC lasers. For both laser mode operations, there is the possibility to set a laser current in the range of 0.1 A - 3 A and pulse duration of 30 ns at the frequencies to the level of 2...
Conference Paper
The paper presents the new infrared detection module developed at the VIGO System Ltd. Its high sensitivity of was achieved by both matching the IR detector to the preamp and minimizing noises. High sensitivity of the detector was achieved by using photodiodes with immersion lens. Immersion lens enables optimization of the detector area, decreasing...
Article
Full-text available
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...
Article
Full-text available
We describe several applications of cavity ring−down spectroscopy (CRDS) for trace matter detection. NO 2 sensor was con− structed 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 NO 3. Successful monitoring of N 2 O in air requires high precisi...
Article
Full-text available
Sensors and Systems for the Detection of Explosive Devices - An Overview The paper presents analyses of current research projects connected with explosive material sensors. Sensors are described assigned to X and γ radiation, optical radiation sensors, as well as detectors applied in gas chromatography, electrochemical and chemical sensors. Further...
Article
Full-text available
Applying CEAS method to UV, VIS, and IR spectroscopy sensors In the paper, several applications of Cavity Enhanced Absorption Spectroscopy (CEAS) for trace mater detection are described. NO 2 sensor was constructed using this technique with blue-violet lasers (395-440 nm). The sensor sensitivity reaches the level of single ppb and it was applied in...
Article
Full-text available
Transmitter with quantum cascade laser for free space optics communication system The paper presents results of experimental tests of the quantum cascade laser from Alpes Lasers company in terms of its application in the optic communication system in an open space. The measurements involved the current - voltage characteristics while measuring also...
Article
Full-text available
In the paper, a description of two-channel of optoelectronic sensor basing on cavity enhanced absorption spectroscopy is presented. In contrast to the typical cavity enhanced absorption spectroscopy systems, here a special optical system is applied. It provides possibility to direct more than one beam of laser radiation into a cavity. Thus, special...
Article
Full-text available
Application of quantum cascade lasers in NO and N2O sensor is described. Cavity enhanced absorption spectroscopy was used for this purpose. The detection was performed at vibronic molecular transitions in spectral regions of 5.23–5.29 µm and 4.46–4.54 µm for NO and N2O, respectively. In order to avoid interferences by the gases contained in atmosph...
Article
Full-text available
The paper presents analysis and preliminary investigations of quantum cascade lasers for free space optics. The lasers radiate in the long wavelength IR spectral range (8-12 1m). Because of lower effects of radiation scattering than in the case of 1.5 1m free space optics, better transmission range can be obtained. The main task of the work was exp...
Conference Paper
Nitrous oxide (N2O) plays a significant role in many different fields therefore its monitoring is an important task. In this paper the opportunity of application of cavity enhanced absorption spectroscopy for N2O detection is presented. This method is a modification of cavity ring down spectroscopy. The laser radiation tuned to absorption line of N...
Article
Full-text available
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...
Article
Full-text available
Application of quantum cascade lasers in NO and N2O sensor is described. Cavity enhanced absorption spectroscopy was used for this purpose. The detection was performed at vibronic molecular transitions in spectral regions of 5.23–5.29 µm and 4.46–4.54 µm for NO and N2O, respectively. In order to avoid interferences by the gases contained in atmosph...