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Sensors Based on Optical and Photonic Devices

A special issue of Sensors (ISSN 1424-8220). This special issue belongs to the section "Physical Sensors".

Deadline for manuscript submissions: 25 June 2024 | Viewed by 27530

Special Issue Editor


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Guest Editor
Department of Electrical and Information Engineering, Politecnico di Bari, Via Edoardo Orabona n. 4, 70125 Bari, Italy
Interests: integrated optoelectronics; nanophotonics; nonlinear photonics; photonic biological/chemical sensors; quantum photonic sensors
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Special Issue Information

Dear Colleagues,

Nowadays, optical and photonic devices are largely recognized due to the development of integrated sensors having low cost, small footprint, and high performance. Moreover, since photonic sensors can be constructed from dielectric materials, they present important advantages over electronic approaches, assuring electrical isolation between the sensor head and the electronic processing module, thus inducing high immunity to electromagnetic interference. Optical and photonic devices are well-established for the design of sensors used in several engineering and physics application fields, such as automotive, aerospace, bio-chemical, medical sensing, as well as monitoring gas levels, temperature and pressure. The aim of this Special Issue is to collect, and make readily available, significant theoretical and/or experimental works in this research field, in order to propose performance improvement strategies and novelty in sensor architectures. Papers addressing a wide range of applications of optical and photonic sensors are sought. Topics include, but are not limited to, recent developments in the following areas: integrated interferometric sensors, ultra-high-Q photonic cavity sensors, fiber-optic-based sensors, photonic-crystal-based sensors, infrared and mid-infrared guided-wave photonic sensors, read-out for optical and photonic sensors.

Dr. Francesco De Leonardis
Guest Editor

Manuscript Submission Information

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Keywords

  • Nanophotonics
  • Integrated optical sensors
  • CMOS-compatible sensors
  • Photonic sensors
  • Fiber optic sensors
  • Photonic crystal sensors
  • Bragg grating-based sensors
  • Interferometric sensors
  • Guided-wave structures for sensing
  • Photonic technologies for sensing

Published Papers (11 papers)

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Research

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14 pages, 3109 KiB  
Article
1/f Noise Mitigation in an Opto-Mechanical Sensor with a Fabry–Pérot Interferometer
by Andrea M. Nelson, Jose Sanjuan and Felipe Guzmán
Sensors 2024, 24(6), 1969; https://doi.org/10.3390/s24061969 - 20 Mar 2024
Viewed by 473
Abstract
Low-frequency and 1/f noise are common measurement limitations that arise in a variety of physical processes. Mitigation methods for these noises are dependent on their source. Here, we present a method for removing 1/f noise of optical origin using a [...] Read more.
Low-frequency and 1/f noise are common measurement limitations that arise in a variety of physical processes. Mitigation methods for these noises are dependent on their source. Here, we present a method for removing 1/f noise of optical origin using a micro-cavity Fabry–Pérot (FP) interferometer. A mechanical modulation of the FP cavity length was applied to a previously studied opto-mechanical sensor. It effectively mimics an up-conversion of the laser frequency, shifting signals to a region where lower white-noise sources dominate and 1/f noise is not present. Demodulation of this signal shifts the results back to the desired frequency range of observation with the reduced noise floor of the higher frequencies. This method was found to improve sensitivities by nearly two orders of magnitude at 1 Hz and eliminated 1/f noise in the range from 1 Hz to 4 kHz. A mathematical model for low-finesse FP cavities is presented to support these results. This study suggests a relatively simple and efficient method for 1/f noise suppression and improving the device sensitivity of systems with an FP interferometer readout. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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12 pages, 5543 KiB  
Article
A Method for Detecting the Vacuum Degree of Vacuum Glass Based on Digital Holography
by Ting Li, Qinghe Song, Guangjun He, Haiting Xia, Haoxiang Li, Jinbin Gui and Haining Dang
Sensors 2023, 23(5), 2468; https://doi.org/10.3390/s23052468 - 23 Feb 2023
Cited by 3 | Viewed by 1339
Abstract
The vacuum degree is the key parameter reflecting the quality and performance of vacuum glass. This investigation proposed a novel method, based on digital holography, to detect the vacuum degree of vacuum glass. The detection system was composed of an optical pressure sensor, [...] Read more.
The vacuum degree is the key parameter reflecting the quality and performance of vacuum glass. This investigation proposed a novel method, based on digital holography, to detect the vacuum degree of vacuum glass. The detection system was composed of an optical pressure sensor, a Mach–Zehnder interferometer and software. The results showed that the deformation of monocrystalline silicon film in an optical pressure sensor could respond to the attenuation of the vacuum degree of vacuum glass. Using 239 groups of experimental data, pressure differences were shown to have a good linear relationship with the optical pressure sensor’s deformations; pressure differences were linearly fitted to obtain the numerical relationship between pressure difference and deformation and to calculate the vacuum degree of the vacuum glass. Measuring the vacuum degree of vacuum glass under three different conditions proved that the digital holographic detection system could measure the vacuum degree of vacuum glass quickly and accurately. The optical pressure sensor’s deformation measuring range was less than 4.5 μm, the measuring range of the corresponding pressure difference was less than 2600 pa, and the measuring accuracy’s order of magnitude was 10 pa. This method has potential market applications. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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9 pages, 2670 KiB  
Communication
Fiber Loop Mirror Based on Optical Fiber Circulator for Sensing Applications
by Paulo Robalinho, Beatriz Soares, António Lobo, Susana Silva and Orlando Frazão
Sensors 2023, 23(2), 618; https://doi.org/10.3390/s23020618 - 05 Jan 2023
Cited by 1 | Viewed by 1631
Abstract
In this paper, a different Fiber Loop Mirror (FLM) configuration with two circulators is presented. This configuration is demonstrated and characterized for sensing applications. This new design concept was used for strain and torsion discrimination. For strain measurement, the interference fringe displacement has [...] Read more.
In this paper, a different Fiber Loop Mirror (FLM) configuration with two circulators is presented. This configuration is demonstrated and characterized for sensing applications. This new design concept was used for strain and torsion discrimination. For strain measurement, the interference fringe displacement has a sensitivity of (0.576 ± 0.009) pm‧με−1. When the FFT (Fast Fourier Transformer) is calculated and the frequency shift and signal amplitude are monitored, the sensitivities are (−2.1 ± 0.3) × 10−4 nm−1 με−1 and (4.9 ± 0.3) × 10−7 με−1, respectively. For the characterization in torsion, an FFT peaks variation of (−2.177 ± 0.002) × 10−12 nm−1/° and an amplitude variation of (1.02 ± 0.06) × 10−3/° are achieved. This configuration allows the use of a wide range of fiber lengths and with different refractive indices for controlling the free spectral range (FSR) and achieving refractive index differences, i.e., birefringence, higher than 10−2, which is essential for the development of high sensitivity physical parameter sensors, such as operating on the Vernier effect. Furthermore, this FLM configuration allows the system to be balanced, which is not possible with traditional FLMs. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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12 pages, 4828 KiB  
Article
Measurement of Gradient Strain Fields with Fiber-Optic Sensors
by Valerii Matveenko, Natalia Kosheleva, Grigorii Serovaev and Andrey Fedorov
Sensors 2023, 23(1), 410; https://doi.org/10.3390/s23010410 - 30 Dec 2022
Cited by 7 | Viewed by 1557
Abstract
The results of measuring gradient strain fields by embedded or mounted point fiber-optic sensors based on Bragg gratings and distributed fiber-optic sensors based on Rayleigh scattering are discussed. Along with the experiment, the results of numerical modeling of strain measurement errors associated with [...] Read more.
The results of measuring gradient strain fields by embedded or mounted point fiber-optic sensors based on Bragg gratings and distributed fiber-optic sensors based on Rayleigh scattering are discussed. Along with the experiment, the results of numerical modeling of strain measurement errors associated with the assumption of uniaxial stress state in the area of the embedded Bragg grating and measurement errors by distributed fiber-optic sensors associated with gage length are presented. Experimental results are presented for 3D printed samples and samples made of polymer composite material. The geometry of the samples was chosen based on the results of numerical simulations, and provides different variants of non-uniform strain distribution under uniaxial tension, including the variant in which the derivative of the strain distribution function changes its sign. A good agreement of numerical results and experimental data obtained by distributed and point fiber-optic sensors in areas where the derivative of the strain distribution function keeps a sign and an increase in the error of strain measurement results by distributed fiber-optic sensors in areas where this derivative changes sign are demonstrated. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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22 pages, 5760 KiB  
Article
Investigation of the Possibility of Using Microspectrometers Based on CMOS Photodiode Arrays in Small-Sized Devices for Optical Diagnostics
by Oleksandra Hotra, Vladimir Firago, Nikolay Levkovich and Konstantin Shuliko
Sensors 2022, 22(11), 4195; https://doi.org/10.3390/s22114195 - 31 May 2022
Cited by 3 | Viewed by 1562
Abstract
The article considers the potential applicability of C12880MA and C11708MA Hamamatsu microspectrometers, which are characterized by an extremely compact design, occupying a small volume of several cubic centimeters, in portable spectrometric equipment with spatial resolution for monitoring the optical properties of condensed scattering [...] Read more.
The article considers the potential applicability of C12880MA and C11708MA Hamamatsu microspectrometers, which are characterized by an extremely compact design, occupying a small volume of several cubic centimeters, in portable spectrometric equipment with spatial resolution for monitoring the optical properties of condensed scattering media. The development of methods for determining the reduced scattering and absorption spectral coefficients of radiation from various scattering materials and products allows us to speak about the possibility of real-time control of the volume concentration of optically active components included in them, for example, fat and water in dairy products. For this, it is necessary to provide sufficiently accurate spectra of diffusely reflected broadband light radiation at different distances between the points of radiation entrance and registration. The aim of the manuscript is to assess the possibility of using the considered microspectrometers in compact devices for optical diagnostics and control of the optical properties of condensed scattering media. The features of the connection diagram of these microspectrometers and the necessary methods for correcting the initially obtained spectral dependencies of diffusive reflection, which will be of interest to developers of spectral diagnostic equipment, are considered in detail. The need to eliminate the influence of the inhomogeneity of dark counts of a CMOS photodiode array is shown. The hardware functions of the C12880MA and C11708MA Hamammatsu microspectrometers, as well as the AvaSpec 2048L fiber-optic spectrometer, were experimentally measured and compared. Methods for correcting the nonlinearity of their reading scales and light characteristics, as well as improving their equivalent spectral resolution using digital Wiener filtering, are described. It is shown that the equivalent spectral resolution of C12880MA and C11708MA microspectrometers can be improved by about 40% when recording smooth spectra, subject to the condition that the resulting side oscillations are small. It is pointed out that in order to reduce the level of side oscillations in the corrected spectra with improved resolution, it is necessary to ensure the smoothness of the original spectra and a good signal-to-noise ratio. A conclusion is made about the possibility of using the considered microspectrometers in portable spectrometric equipment with careful consideration of their characteristics, the features of their switching circuit, and the necessary software. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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13 pages, 6386 KiB  
Communication
Verification of Angular Response of Sky Quality Meter with Quasi-Punctual Light Sources
by Mirco Bartolomei, Lorenzo Olivieri, Carlo Bettanini, Stefano Cavazzani and Pietro Fiorentin
Sensors 2021, 21(22), 7544; https://doi.org/10.3390/s21227544 - 13 Nov 2021
Cited by 6 | Viewed by 1746
Abstract
Sky Quality Meter (SQM) is a commercial instrument based on photometers widely used by amateur astronomers for skyglow measurement from the ground. In the framework of the MINLU project, two SQM-LE units were integrated in an autonomous sensor suite realized and tested at [...] Read more.
Sky Quality Meter (SQM) is a commercial instrument based on photometers widely used by amateur astronomers for skyglow measurement from the ground. In the framework of the MINLU project, two SQM-LE units were integrated in an autonomous sensor suite realized and tested at University of Padova for monitoring light pollution from drones or sounding balloons. During the ground tests campaign before airborne measurement, the performance of both SQM units was verified in laboratory using controlled light sources as a reference input; the results showed that both units presented an angular response deviating consistently from the expected performance and that the sensors’ field of view was larger than the one declared in the manufacturer’s datasheet. This aspect in particular would affect direct skyglow measurements during flight as light sources close to the boundaries of the field of view would not be attenuated but instead detected by the sensors. As a direct consequence, the measurement of low-intensity skyglows at stratospheric altitudes could be affected by high-intensity punctual sources acting as lateral disturbances. A dedicated test campaign was therefore conceived and realized to investigate SQM unit response to light sources in the field of view and identify the true angular response curve; the setup consisted in a controlled rotatory stage moving the unit in front of a fixed diffusive light source. Different test conditions were used to validate the experimental procedure, demonstrating the repeatability of the measurements. This paper presents the experimental campaign and the resulting SQM angular response curve; results indicate for both SQMs a larger than expected field of view and the presence of a double peak in the angular response, which is likely related to a non-perfect alignment of SQMs collimation optics. Furthermore, the wider resulting curves suggest that the contribution of lateral sources is more prominent with respect to the response predicted by the manufacturer. For this reason, the utilization of baffles to restrict SQMs field of view is analyzed to minimize the disturbance of lateral light sources and two different geometries are presented. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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24 pages, 12039 KiB  
Article
Inquiry into the Temperature Changes of Rock Massif Used in Energy Production in Relation to Season
by Martin Klempa, Jan Latal, Barbora Grafova, Michal Matloch Porzer, Mojmir Vrtek, Antonin Kunz and Petr Siska
Sensors 2021, 21(21), 7027; https://doi.org/10.3390/s21217027 - 23 Oct 2021
Viewed by 1870
Abstract
This research was undertaken to perform and evaluate the temperature measurement in the ground utilized as an energy source with the goal to determine whether significant temperature variations occur in the subsurface during the heating season. The research infrastructure situated on our University [...] Read more.
This research was undertaken to perform and evaluate the temperature measurement in the ground utilized as an energy source with the goal to determine whether significant temperature variations occur in the subsurface during the heating season. The research infrastructure situated on our University campus was used to assess any variations. The observations were made at the so called “Small Research Polygon” that consists of 8 monitoring boreholes (Borehole Heat Exchangers) situated around a borehole used as an energy source. During the heating season, a series of monthly measurements are made in the monitoring boreholes using a distributed temperature system (DTS). Raman back-scattered light is analysed using Optical Frequency Time Domain Reflectometry (OTDR). Our results indicate that no noticeable changes in temperature occur during the heating season. We have observed an influence of long-term variations of the atmospheric conditions up to the depth of a conventional BHE (≈100 m). The resulting uncertainty in related design input parameters (ground thermal conductivity) was evaluated by using a heat production simulation. Production data during one heating season at our research facilities were evaluated against the design of the system. It is possible to construct smaller geothermal installations with appropriate BHE design that will have a minimal impact on the temperature of the surrounding rock mass and the system performance. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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Review

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28 pages, 2289 KiB  
Review
A Review: Application and Implementation of Optic Fibre Sensors for Gas Detection
by Thomas Allsop and Ronald Neal
Sensors 2021, 21(20), 6755; https://doi.org/10.3390/s21206755 - 12 Oct 2021
Cited by 15 | Viewed by 4603
Abstract
At the present time, there are major concerns regarding global warming and the possible catastrophic influence of greenhouse gases on climate change has spurred the research community to investigate and develop new gas-sensing methods and devices for remote and continuous sensing. Furthermore, there [...] Read more.
At the present time, there are major concerns regarding global warming and the possible catastrophic influence of greenhouse gases on climate change has spurred the research community to investigate and develop new gas-sensing methods and devices for remote and continuous sensing. Furthermore, there are a myriad of workplaces, such as petrochemical and pharmacological industries, where reliable remote gas tests are needed so that operatives have a safe working environment. The authors have concentrated their efforts on optical fibre sensing of gases, as we became aware of their increasing range of applications. Optical fibre gas sensors are capable of remote sensing, working in various environments, and have the potential to outperform conventional metal oxide semiconductor (MOS) gas sensors. Researchers are studying a number of configurations and mechanisms to detect specific gases and ways to enhance their performances. Evidence is growing that optical fibre gas sensors are superior in a number of ways, and are likely to replace MOS gas sensors in some application areas. All sensors use a transducer to produce chemical selectivity by means of an overlay coating material that yields a binding reaction. A number of different structural designs have been, and are, under investigation. Examples include tilted Bragg gratings and long period gratings embedded in optical fibres, as well as surface plasmon resonance and intra-cavity absorption. The authors believe that a review of optical fibre gas sensing is now timely and appropriate, as it will assist current researchers and encourage research into new photonic methods and techniques. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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34 pages, 5517 KiB  
Review
Recent Advances in Biomedical Photonic Sensors: A Focus on Optical-Fibre-Based Sensing
by Mario Ochoa, José Francisco Algorri, Pablo Roldán-Varona, Luis Rodríguez-Cobo and José Miguel López-Higuera
Sensors 2021, 21(19), 6469; https://doi.org/10.3390/s21196469 - 28 Sep 2021
Cited by 29 | Viewed by 5665
Abstract
In this invited review, we provide an overview of the recent advances in biomedical photonic sensors within the last five years. This review is focused on works using optical-fibre technology, employing diverse optical fibres, sensing techniques, and configurations applied in several medical fields. [...] Read more.
In this invited review, we provide an overview of the recent advances in biomedical photonic sensors within the last five years. This review is focused on works using optical-fibre technology, employing diverse optical fibres, sensing techniques, and configurations applied in several medical fields. We identified technical innovations and advancements with increased implementations of optical-fibre sensors, multiparameter sensors, and control systems in real applications. Examples of outstanding optical-fibre sensor performances for physical and biochemical parameters are covered, including diverse sensing strategies and fibre-optical probes for integration into medical instruments such as catheters, needles, or endoscopes. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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Other

Jump to: Research, Review

7 pages, 2163 KiB  
Opinion
How Reliable Is Pyramidal Wavefront-Based Sensor Aberrometry in Measuring the In Vivo Optical Behaviour of Multifocal IOLs?
by Francesco D’Oria, Giacomo Scotti, Alessandra Sborgia, Francesco Boscia and Giovanni Alessio
Sensors 2023, 23(7), 3534; https://doi.org/10.3390/s23073534 - 28 Mar 2023
Cited by 1 | Viewed by 1412
Abstract
Cataract or refractive lens surgery, along with the implantation of multifocal intraocular lenses (MF-IOL), enables a complete range of functional far, near and intermediate vision. Refractive, diffractive and extended depth of focus (EDoF) or combination of these principles represent the technology used to [...] Read more.
Cataract or refractive lens surgery, along with the implantation of multifocal intraocular lenses (MF-IOL), enables a complete range of functional far, near and intermediate vision. Refractive, diffractive and extended depth of focus (EDoF) or combination of these principles represent the technology used to obtain this multifocality. Aberrometry makes it possible to study the aberrations induced by MF-IOLs. Among the different optical principles available to measure ocular aberrations, pyramidal wavefront-based sensor (PWS) aberrometry shows the highest resolution with MF-IOLs. Retinal image quality measured by a PWS aberrometer differed significantly according to the technology of the implanted lens. Monofocal and diffractive lenses showed the highest values of far-distance retinal image quality, followed by refractive and EDoF lenses; however, retinal image quality analysed in diffractive lenses appears to be more dependent on residual refractive error. Considering this limitation, PWS-aberrometry could be used to compare diffractive lenses. Nevertheless, further studies are needed to provide additional information about the clinical retinal image quality of MF-IOLs and to help surgeons in the important preoperative selection of IOLs. Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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25 pages, 69500 KiB  
Perspective
Sensing Using Light: A Key Area of Sensors
by José Miguel López-Higuera
Sensors 2021, 21(19), 6562; https://doi.org/10.3390/s21196562 - 30 Sep 2021
Cited by 2 | Viewed by 3872
Abstract
This invited featured paper offers a Doctrinal Conception of sensing using Light (SuL) as an “umbrella” in which any sensing approach using Light Sciences and Technologies can be easily included. The key requirements of a sensing system will be quickly introduced by using [...] Read more.
This invited featured paper offers a Doctrinal Conception of sensing using Light (SuL) as an “umbrella” in which any sensing approach using Light Sciences and Technologies can be easily included. The key requirements of a sensing system will be quickly introduced by using a bottom-up methodology. Thanks to this, it will be possible to get a general conception of a sensor using Light techniques and know some related issues, such as its main constituted parts and types. The case in which smartness is conferred to the device is also considered. A quick “flight” over 10 significant cases using different principles, techniques, and technologies to detect diverse measurands in various sector applications is offered to illustrate this general concept. After reading this paper, any sensing approach using Light Sciences and Technologies may be easily included under the umbrella: sensing using Light or photonic sensors (PS). Full article
(This article belongs to the Special Issue Sensors Based on Optical and Photonic Devices)
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Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

Title: Performance assessment of a Distributed Optical Fiber Sensing (DOFS) system under controlled laboratory conditions, with a view to structural health monitoring of concrete structures
Authors: Karim Benzarti; Marc Quiertant; Jean-Marie Hénault
Affiliation: University Eiffel
Abstract: Structural Health Monitoring is an important aspect of the life-cycle management of civil engineering structures. Truly distributed fiber optic sensors are able to provide relevant information on large structures. However, a preliminary performance assessment is required prior to any industrial application. Based on the European guide FD CEN TR 14748, a qualification method was developed and applied to a specific measuring system composed of an interrogator and a multi-fiber cable, providing strain profiles in concrete with high resolution and sensitivity. Tests were carried out under controlled laboratory conditions on the fiber optic cable, outside the concrete medium during the first stage, and then embedded in concrete structures.

Title: A Review: Application and implementation of Optic Fibre Sensors for Gas Detection
Authors: Thomas Allsop 1,2 * and Ron Neal 3
Affiliation: 1 School of Engineering and Computer Science, University of Hull, Hull, HU6 7RX, UK;
2. Aston Institute of Photonic Technologies (AIPT), Aston University, Aston Triangle, Birmingham B4 7ET, UK
3. School of Computing, Communications and Electronics, University of Plymouth, PL4 8AA, UK
Abstract: At the present time, there are major concerns regards global warming and possible catastrophic influence of greenhouse gases on climate change has spurred the research community to investigate and develop new gas sensing methods and devices for remote and continuous sensing. Furthermore, there are myriad of workplaces, such as, petrochemical and pharmacological industries where reliable remote gas-test is needed so that operatives have a safe working environment. The authors have concentrated their efforts into optical fibre sensing of gases as we became aware of the increasing range of applications. Optical fibre gas sensors are capable of remote sensing, working in various environments and have the potential to outperform conventional Metal Oxide Semiconductor (MOS) gas sensors. Researchers are studying a number of configurations and mechanisms to detect specific gases and ways to enhance their performance. Evidence is growing that optical fibre gas sensors are superior in a number of ways and are likely to replace MOS gas sensors in some application areas. All sensors use a transducer to produce chemical selectivity by means of an overlay coating material that yields a binding reaction. A number of different structural designs have been, and are under investigation. Examples are tilted Brag gratings and long period gratings embedded in optical fibres. Also, surface plasmon resonance and intra-cavity absorption. The authors believe that a review of optical fibre gas sensors is now timely and appropriate as it will assist current researchers and encourage research into new photonic methods and techniques.

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