Spatially disordered but uniformly distributed point patterns characterized by so-called blue-noise long-range spatial correlations are of great benefit in computer graphics, especially in spatial dithering thanks to the spatial isotropy. Herein, the potential photonic properties of blue-noise disordered, homogeneous point processes based on farthest-point optimization are numerically investigated for silicon photonics. The photonic properties of blue-noise two-dimensional patterns are studied as a function of the filling fraction and benchmarked with photonic crystals with a triangular lattice. Ultrawide and omnidirectional photonic band gaps spanning most of the visible spectrum are found with estimates of gap–midgap ratios of up to 55.4% for transverse magnetic polarization, 59.4% for transverse electric polarization, and 32.7% for complete band gaps. The waveguiding effect in azimuthal defect lines is also numerically evaluated. These results corroborate the idea that long-range correlated disordered structures are helpful for engineering novel devices with the additional degree of freedom of spatial isotropy, and capable of bandgap opening even without total suppression of infinite-wavelength density fluctuations.
{"title":"Blue-Noise-Based Disordered Photonic Structures Show Isotropic and Ultrawide Band Gaps","authors":"Edoardo De Tommasi, Silvia Romano, Gianluigi Zito","doi":"10.3390/opt4040042","DOIUrl":"https://doi.org/10.3390/opt4040042","url":null,"abstract":"Spatially disordered but uniformly distributed point patterns characterized by so-called blue-noise long-range spatial correlations are of great benefit in computer graphics, especially in spatial dithering thanks to the spatial isotropy. Herein, the potential photonic properties of blue-noise disordered, homogeneous point processes based on farthest-point optimization are numerically investigated for silicon photonics. The photonic properties of blue-noise two-dimensional patterns are studied as a function of the filling fraction and benchmarked with photonic crystals with a triangular lattice. Ultrawide and omnidirectional photonic band gaps spanning most of the visible spectrum are found with estimates of gap–midgap ratios of up to 55.4% for transverse magnetic polarization, 59.4% for transverse electric polarization, and 32.7% for complete band gaps. The waveguiding effect in azimuthal defect lines is also numerically evaluated. These results corroborate the idea that long-range correlated disordered structures are helpful for engineering novel devices with the additional degree of freedom of spatial isotropy, and capable of bandgap opening even without total suppression of infinite-wavelength density fluctuations.","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"11 S1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135872954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sébastien R. Mouchet, Fabio Cortesi, Bojana Bokic, Vladimir Lazovic, Pete Vukusic, N. Justin Marshall, Branko Kolaric
Reactive oxygen species (ROS) such as superoxide radicals O2−, hydroxyl radicals OH−, and hydrogen peroxide H2O2 may have detrimental effects on marine organisms, including their integuments and visual appearances. Although some studies have described the impact of ROS on marine ecosystems and species ecology, the influence on the optical response of the integuments of marine species and on their visual appearances remains unknown. In this article, we used histology and optical characterisation to show, for the first time, that skin melanophores (melanin-containing chromophores) of the coral reef fish, Stegastes apicalis, change their shapes and fluorescent proprieties upon oxidation with H2O2 radicals. Our observations also suggest that pheomelanosomes may occur in fish integuments, where, previously, it was thought that fish melanosomes only contain eumelanin. This investigation relied on light and electron microscopy and steady-state fluorimetry, as well as time-resolved streak imaging systems. We suggest that the changes in the morphological and spectral characteristics of melanophores can be used as a marker of physiological stress induced by environmental factors such as ROS. Moreover, S. apicalis may be used as a potential model for studying the interaction between the surrounding environment and natural organisms in biologically diverse ecosystems, such as the Great Barrier Reef in Australia.
{"title":"Morphological and Optical Modification of Melanosomes in Fish Integuments upon Oxidation","authors":"Sébastien R. Mouchet, Fabio Cortesi, Bojana Bokic, Vladimir Lazovic, Pete Vukusic, N. Justin Marshall, Branko Kolaric","doi":"10.3390/opt4040041","DOIUrl":"https://doi.org/10.3390/opt4040041","url":null,"abstract":"Reactive oxygen species (ROS) such as superoxide radicals O2−, hydroxyl radicals OH−, and hydrogen peroxide H2O2 may have detrimental effects on marine organisms, including their integuments and visual appearances. Although some studies have described the impact of ROS on marine ecosystems and species ecology, the influence on the optical response of the integuments of marine species and on their visual appearances remains unknown. In this article, we used histology and optical characterisation to show, for the first time, that skin melanophores (melanin-containing chromophores) of the coral reef fish, Stegastes apicalis, change their shapes and fluorescent proprieties upon oxidation with H2O2 radicals. Our observations also suggest that pheomelanosomes may occur in fish integuments, where, previously, it was thought that fish melanosomes only contain eumelanin. This investigation relied on light and electron microscopy and steady-state fluorimetry, as well as time-resolved streak imaging systems. We suggest that the changes in the morphological and spectral characteristics of melanophores can be used as a marker of physiological stress induced by environmental factors such as ROS. Moreover, S. apicalis may be used as a potential model for studying the interaction between the surrounding environment and natural organisms in biologically diverse ecosystems, such as the Great Barrier Reef in Australia.","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"73 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135271070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Seán Ó Dúill, Leidy Rodriguez, David Alvarez-Outerelo, Francisco J. Diaz-Otero, Ankit Sharma, Frank Smyth, Liam P. Barry
We present the results of the detected voltage distribution of a quantum random number generator (QRNG) based on a photonic integrated circuit comprising a semiconductor laser, delay interferometer and photodetector. We find that the integrated QRNG system behaves as expected for a QRNG from discrete gain-switched laser sources, especially exhibiting all of the peculiarities of the random voltage distribution and behaving as previously demonstrated for a discrete optical component setup. The biggest advantage of having all of the components integrated into a single chip is that only electrical connections are needed to operate the system, without the need for tricky and expensive optical alignment to external circuitry. We supply results showing that a random bit stream created from the random numbers passes the NIST statistical test suite tests, thus demonstrating the feasibility to generate random numbers via quantum means at gigabit/s rates from a single photonic integrated circuit. All of our results are backed by numerical simulations.
{"title":"Operation of an Electrical-Only-Contact Photonic Integrated Chip for Quantum Random Number Generation Using Laser Gain-Switching","authors":"Seán Ó Dúill, Leidy Rodriguez, David Alvarez-Outerelo, Francisco J. Diaz-Otero, Ankit Sharma, Frank Smyth, Liam P. Barry","doi":"10.3390/opt4040040","DOIUrl":"https://doi.org/10.3390/opt4040040","url":null,"abstract":"We present the results of the detected voltage distribution of a quantum random number generator (QRNG) based on a photonic integrated circuit comprising a semiconductor laser, delay interferometer and photodetector. We find that the integrated QRNG system behaves as expected for a QRNG from discrete gain-switched laser sources, especially exhibiting all of the peculiarities of the random voltage distribution and behaving as previously demonstrated for a discrete optical component setup. The biggest advantage of having all of the components integrated into a single chip is that only electrical connections are needed to operate the system, without the need for tricky and expensive optical alignment to external circuitry. We supply results showing that a random bit stream created from the random numbers passes the NIST statistical test suite tests, thus demonstrating the feasibility to generate random numbers via quantum means at gigabit/s rates from a single photonic integrated circuit. All of our results are backed by numerical simulations.","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136263629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Laser-induced periodic surface structures (LIPSS) have gained significant attention due to their ability to modify the surface morphology of materials at the micro-nanoscale and show great promise for surface functionalization applications. In this study, we specifically investigate the formation of LIPSS in silicon substrates and explore their impact on surface-enhanced Raman spectroscopy (SERS) applications. This study reveals a stepwise progression of LIPSS formation in silicon, involving three distinct stages of LIPSS: (1) integrated low-spatial-frequency LIPSS (LSFL) and high-spatial-frequency LIPSS (HSFL), (2) principally LSFL and, (3) LSFL at the edge of the irradiated spot, elucidating the complex interplay between laser fluence, pulse number, and resulting surface morphology. Furthermore, from an application standpoint, these high-quality multi-scale periodic patterns lead to the next step of texturing the entire silicon surface with homogeneous LIPSS for SERS application. The potential of LIPSS-fabricated silicon substrates for enhancing SERS performance is investigated using thiophenol as a test molecule. The results indicate that the Au-coated combination of LSFL and HSFL substrates showcased the highest enhancement factor (EF) of 1.38×106. This pronounced enhancement is attributed to the synergistic effects of localized surface plasmon resonance (LSPR) and surface plasmon polaritons (SPPs), intricately linked to HSFL and LSFL characteristics. These findings contribute to our understanding of LIPSS formation in silicon and their applications in surface functionalization and SERS, paving the way for sensing platforms.
{"title":"Investigating Laser-Induced Periodic Surface Structures (LIPSS) Formation in Silicon and Their Impact on Surface-Enhanced Raman Spectroscopy (SERS)","authors":"Hardik Vaghasiya, Paul-Tiberiu Miclea","doi":"10.3390/opt4040039","DOIUrl":"https://doi.org/10.3390/opt4040039","url":null,"abstract":"Laser-induced periodic surface structures (LIPSS) have gained significant attention due to their ability to modify the surface morphology of materials at the micro-nanoscale and show great promise for surface functionalization applications. In this study, we specifically investigate the formation of LIPSS in silicon substrates and explore their impact on surface-enhanced Raman spectroscopy (SERS) applications. This study reveals a stepwise progression of LIPSS formation in silicon, involving three distinct stages of LIPSS: (1) integrated low-spatial-frequency LIPSS (LSFL) and high-spatial-frequency LIPSS (HSFL), (2) principally LSFL and, (3) LSFL at the edge of the irradiated spot, elucidating the complex interplay between laser fluence, pulse number, and resulting surface morphology. Furthermore, from an application standpoint, these high-quality multi-scale periodic patterns lead to the next step of texturing the entire silicon surface with homogeneous LIPSS for SERS application. The potential of LIPSS-fabricated silicon substrates for enhancing SERS performance is investigated using thiophenol as a test molecule. The results indicate that the Au-coated combination of LSFL and HSFL substrates showcased the highest enhancement factor (EF) of 1.38×106. This pronounced enhancement is attributed to the synergistic effects of localized surface plasmon resonance (LSPR) and surface plasmon polaritons (SPPs), intricately linked to HSFL and LSFL characteristics. These findings contribute to our understanding of LIPSS formation in silicon and their applications in surface functionalization and SERS, paving the way for sensing platforms.","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135728793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Contrast is not uniquely defined in the literature. There is a need for a contrast measure that scales linearly and monotonically with the optical scattering depth of a translucent scattering layer that covers an object. Here, we address this issue by proposing an image contrast metric, which we call the Haziness contrast metric. In its essence, the Haziness contrast compares normalized histograms of multiple blocks of the image, a pair at a time. Subsequently, we test several prominent contrast metrics in the literature, as well as the new one, by using milk as a scattering medium in front of an object to simulate a decline in image contrast. Compared to other contrast metrics, the Haziness contrast metric is monotonic and close to linear for increasing density of the scattering material, compared with other metrics in the literature. The Haziness contrast has a wider dynamic range, and it correctly predicts the order of scattering depth for all the channels in the RGB image. Utilization of the metric to evaluate the performance assessment of dehazing algorithms is also suggested.
{"title":"Image Haziness Contrast Metric Describing Optical Scattering Depth","authors":"André R. Vitor, Arie Shaus, George C. Cardoso","doi":"10.3390/opt4040038","DOIUrl":"https://doi.org/10.3390/opt4040038","url":null,"abstract":"Contrast is not uniquely defined in the literature. There is a need for a contrast measure that scales linearly and monotonically with the optical scattering depth of a translucent scattering layer that covers an object. Here, we address this issue by proposing an image contrast metric, which we call the Haziness contrast metric. In its essence, the Haziness contrast compares normalized histograms of multiple blocks of the image, a pair at a time. Subsequently, we test several prominent contrast metrics in the literature, as well as the new one, by using milk as a scattering medium in front of an object to simulate a decline in image contrast. Compared to other contrast metrics, the Haziness contrast metric is monotonic and close to linear for increasing density of the scattering material, compared with other metrics in the literature. The Haziness contrast has a wider dynamic range, and it correctly predicts the order of scattering depth for all the channels in the RGB image. Utilization of the metric to evaluate the performance assessment of dehazing algorithms is also suggested.","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136098862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The rare-earth ions in crystals such as terbium (YTaO4:Tb3+) and europium (YTaO4:Eu3+)-activated yttrium tantalate phosphors have a number of attractive features that predetermine their crucial role in practical application in contemporary optoelectronic devices. In this article, we employ the group-theoretical arguments aimed to reveal the group-theoretical classification of the crystal field levels and selection rules for the allowed optical transition between the crystal field components of Tb3+ and Eu3+ of the low symmetry crystal field in the activated yttrium tantalate phosphors. We also establish possible polarization rules for the lines corresponding to the allowed transitions. We deduce the symmetry-assisted results for the selection rules in the optical transitions accompanied by the absorption/emission of the vibrational quanta. The selection rules for the vibronic satellites of the zero-phonon lines are expected to be useful for the identification of the lines in the spectra of rare-earth ions with a weak vibronic coupling. The results of the low-temperature measurements of photoluminescence under the 325 nm excitation are in compliance with the group-theoretical analysis. The aim of the paper is to establish symmetry-assisted results that are the background of the quantitative crystal field theory based on the quantum-mechanical consideration.
{"title":"Optical Lines in Europium and Terbium-Activated Yttrium Tantalate Phosphor: Combined Experimental and Group-Theoretical Analysis","authors":"Michael Nazarov, B. Tsukerblat","doi":"10.3390/opt4030037","DOIUrl":"https://doi.org/10.3390/opt4030037","url":null,"abstract":"The rare-earth ions in crystals such as terbium (YTaO4:Tb3+) and europium (YTaO4:Eu3+)-activated yttrium tantalate phosphors have a number of attractive features that predetermine their crucial role in practical application in contemporary optoelectronic devices. In this article, we employ the group-theoretical arguments aimed to reveal the group-theoretical classification of the crystal field levels and selection rules for the allowed optical transition between the crystal field components of Tb3+ and Eu3+ of the low symmetry crystal field in the activated yttrium tantalate phosphors. We also establish possible polarization rules for the lines corresponding to the allowed transitions. We deduce the symmetry-assisted results for the selection rules in the optical transitions accompanied by the absorption/emission of the vibrational quanta. The selection rules for the vibronic satellites of the zero-phonon lines are expected to be useful for the identification of the lines in the spectra of rare-earth ions with a weak vibronic coupling. The results of the low-temperature measurements of photoluminescence under the 325 nm excitation are in compliance with the group-theoretical analysis. The aim of the paper is to establish symmetry-assisted results that are the background of the quantitative crystal field theory based on the quantum-mechanical consideration.","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73271377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-31DOI: 10.11648/j.optics.20221101.12
Svishch Vladimir
{"title":"Measuring the Pecular Velocity of the System Without Going Beyond It","authors":"Svishch Vladimir","doi":"10.11648/j.optics.20221101.12","DOIUrl":"https://doi.org/10.11648/j.optics.20221101.12","url":null,"abstract":"","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"49 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83072582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Polyakova, A. Soloveva, P. Peretyagin, A. Belova, Kseniya L. Belyaeva
The development of anti-pain technologies in the complex treatment of pain syndromes is one of the most urgent tasks of modern medicine. We undertook a placebo-controlled experimental study of the therapeutic potential of low-intensity laser radiation when applied to acupuncture points that are directly related to the autonomic nervous system. The adaptation effect of puncture photobiomodulation on the induction of stress-mediated autonomic reactions, oxidative metabolism and microcirculation in animals during the acute phase of pain stress was revealed. The data obtained are of interest for use in the complex rehabilitation of patients with pain syndromes.
{"title":"Photobiomodulation for Correction of Systemic Disorders of Experimental Pain Syndromes","authors":"A. Polyakova, A. Soloveva, P. Peretyagin, A. Belova, Kseniya L. Belyaeva","doi":"10.3390/opt4030036","DOIUrl":"https://doi.org/10.3390/opt4030036","url":null,"abstract":"The development of anti-pain technologies in the complex treatment of pain syndromes is one of the most urgent tasks of modern medicine. We undertook a placebo-controlled experimental study of the therapeutic potential of low-intensity laser radiation when applied to acupuncture points that are directly related to the autonomic nervous system. The adaptation effect of puncture photobiomodulation on the induction of stress-mediated autonomic reactions, oxidative metabolism and microcirculation in animals during the acute phase of pain stress was revealed. The data obtained are of interest for use in the complex rehabilitation of patients with pain syndromes.","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89000296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Mayeur, J. Volatier, G. Druart, F. Cau, E. Tartas, Alain Durand
We present an automated method of finding different freeform dioptric starting systems, working in the infrared region, for further optimization in commercial optical design software. Our developed method couples the simultaneous multiple surface (SMS) method, introduced by Benítez and Miñano, with automatic optimization in Zemax OpticStudio. The method allows an optical designer to explore the merit function (MF) landscape of freeform optical problems. In this article, we apply our method to a size, weight, and power (SWaP) problem, and we compare our designed system with a system found in the literature that has the same aperture of F/1.2. Then, we increase the aperture of the system up to F/0.9, taking advantage of the use of freeform surfaces.
{"title":"Automatic Method of Exploring the Landscape of Freeform Dioptric Optical Problems, Working in the Infrared Region","authors":"T. Mayeur, J. Volatier, G. Druart, F. Cau, E. Tartas, Alain Durand","doi":"10.3390/opt4030035","DOIUrl":"https://doi.org/10.3390/opt4030035","url":null,"abstract":"We present an automated method of finding different freeform dioptric starting systems, working in the infrared region, for further optimization in commercial optical design software. Our developed method couples the simultaneous multiple surface (SMS) method, introduced by Benítez and Miñano, with automatic optimization in Zemax OpticStudio. The method allows an optical designer to explore the merit function (MF) landscape of freeform optical problems. In this article, we apply our method to a size, weight, and power (SWaP) problem, and we compare our designed system with a system found in the literature that has the same aperture of F/1.2. Then, we increase the aperture of the system up to F/0.9, taking advantage of the use of freeform surfaces.","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77374317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abraham A. Quiñones-Flores, J. Guzmán-Sepúlveda, A. Castillo-Guzmán
A relative humidity (RH) fiber optic sensor is demonstrated based on the multimode interference (MMI) phenomenon utilizing a no-core fiber (NCF) coated with polyvinyl alcohol (PVA). The sensor’s structure is simple and consists of a section of NCF spliced between two standard single-mode fibers (SMFs). The fabrication and testing of a tapered version with enhanced sensitivity is also presented. The native MMI sensor showed a sensitivity of 5.6nm/RH%, in the range from 87 RH% to 93 RH%, while the tapered one exhibited an increased sensitivity of 6.6nm/RH%, in the range from 91.5 RH% to 94 RH%. The sensitivity values obtained with these MMI sensors are at least twice as large as the most sensitive fiber optics humidity sensor reported in the literature in a similar RH range.
{"title":"Relative Humidity Measurement Based on a Tapered, PVA-Coated Fiber Optics Multimode Interference Sensor","authors":"Abraham A. Quiñones-Flores, J. Guzmán-Sepúlveda, A. Castillo-Guzmán","doi":"10.3390/opt4030034","DOIUrl":"https://doi.org/10.3390/opt4030034","url":null,"abstract":"A relative humidity (RH) fiber optic sensor is demonstrated based on the multimode interference (MMI) phenomenon utilizing a no-core fiber (NCF) coated with polyvinyl alcohol (PVA). The sensor’s structure is simple and consists of a section of NCF spliced between two standard single-mode fibers (SMFs). The fabrication and testing of a tapered version with enhanced sensitivity is also presented. The native MMI sensor showed a sensitivity of 5.6nm/RH%, in the range from 87 RH% to 93 RH%, while the tapered one exhibited an increased sensitivity of 6.6nm/RH%, in the range from 91.5 RH% to 94 RH%. The sensitivity values obtained with these MMI sensors are at least twice as large as the most sensitive fiber optics humidity sensor reported in the literature in a similar RH range.","PeriodicalId":54548,"journal":{"name":"Progress in Optics","volume":"133 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72550928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}