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1

Nowe strategie wysokociśnieniowej manometrii luminescencyjnej

Runowski Marcin

Wiadomości Chemiczne

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2023

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[Z] 77, 11-12

11--12

EN

Optical pressure sensors, namely luminescent manometers, offer new possibilities for studying and monitoring changes in the physicochemical properties of materials under extreme conditions in a remote and non-invasive manner. This can be achieved through the monitoring and analysis of selected spectroscopic parameters, such as band intensity ratios, emission line shifts, or luminescent lifetimes. However, a limitation for optical readings usually arises from the quenching of the luminescent signal in the given material, i.e., in the active part of the sensor under elevated pressure conditions. In this article, new strategies for the development of advanced and ultra-sensitive luminescent pressure sensors, mainly based on inorganic materials doped with lanthanide or d-block metal ions, will be presented and analyzed. Factors influencing the enhancement of luminescent signal intensity and sensor sensitivity will be discussed. These objectives can be achieved through the appropriate selection of the soft host matrices (of high compressibility), doping with various lanthanide and d-block metal ions, using interionic energy transfer, pressure-driven configurational crossover, as well as the use of materials exhibiting both photo- and mechanoluminescence phenomena. Finally, the development of bi-functional pressure and temperature sensors operating under extreme conditions will also be discussed.

2

The optical measurement method for structural twist monitoring with using tilted Bragg grating sensor

Harasim D., Kusambayeva N.

Przegląd Elektrotechniczny

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2018

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R. 94, nr 7

62--65

EN

This paper presents the proposal for application of optical fiber sensor based on tilted Bragg gratings (TFBGs) for monitoring of structural twist. Article also shows the fully optical method for sensor signal demodulation using single passive fiber structure as traditional fiber Bragg grating (FBG). In such system the power of light reflected from FBG carries the information about twist between selected sections of monitored structure. This allows to avoid the expensive and vulnerable equipment for demodulation of TFBG spectral properties.

PL

Niniejszy artykuł przedstawia propozycję zastosowania czujnika światłowodowego opartego o skośną siatkę Bragga (ang. TFBG) do monitorowania kąta skrętu. Przedstawiona została także metoda demodulacji sygnału optycznego z takiego czujnika za pomocą pasywnego elementu filtrującego w postaci tradycyjnej prostej siatki Bragga. W takim układzie, moc światła odbitego od siatki filtrującej niesie informację o skręcie pomiędzy wyznaczonymi segmentami badanej struktury. Zastosowanie takiej metody pozwoli na wyeliminowanie konieczności użycia wartościowego i delikatnego sprzętu specjalistycznego do określenia charakterystyk spektralnych czujnika.

3

Frequency-multiplexed gas sensing using chirped laser molecular spectroscopy

Tomaszewska D., Jaworski P., Nikodem M.

Opto-Electronics Review

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2018

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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.

4

Theoretical investigation of slab waveguide sensor using anisotropic metamaterial

Taya S. A.

Optica Applicata

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2015

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Vol. 45, nr 3

405--417

EN

A three-layer slab waveguide with air as a substrate, lossless dielectric as a guiding film, and anisotropic double negative material as a cladding is explored as an optical sensor for refractometry applications. The double negative material is assumed to have a negative electric permittivity and magnetic permeability only along the wave propagation direction. The sensitivity of a guided mode to the variation in the refractive index of air substrate is derived and studied for the first few guided modes. It is found that the sensitivity can be enhanced with decreasing the guided light frequency as well as the film thickness. The sensitivity can reach 100% for some waveguide configurations.

5

Accuracy improvement of bulk optical polarization interferometric sensors

Wierzba P., Kosmowski B. B.

Optica Applicata

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2005

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Vol. 35, nr 1

171-185

EN

Interferometric sensors using bulk optical components exhibit very high measurement resolution. In order to attain high accuracy, these sensors are often implemented as polarization interferometers, in which stable and well-defined states of polarization are maintained. Unwanted phenomena degrading accuracy of this class of sensors are disscused in the paper. Signal processing technique which improves accuracy of polarization interferometric sensors is presented. Its implementation using analogue circuits is discussed and a method of of improving its performance is devised.