A few-mode microfiber knot resonator (FM-MKR) incorporating a polyvinyl alcohol (PVA) is investigated for measurement of relative humidity (RH). Two modes, such as HE11 and HE12, are excited and interfered in a nonadiabatically tapered structure of the single-mode fiber (SMF). After making a tie with the few-mode microfiber, the FM-MKR is fabricated. In the FM-MKR, two modes, such as HE11 and HE12, must be circulated within the optical knot and cross-coupled independently with a phase delay. By optimizing the diameter of the microfiber, the difference of group effective refractive indices between two modes is dramatically suppressed resulting in the improvement of RH sensitivity of the proposed FM-MKR.
{"title":"Relative humidity sensor based on a few-mode microfiber knot resonator by mitigating group index difference","authors":"D. A. Le, Seungmin Lee, Young-Geun Han","doi":"10.1117/12.2263972","DOIUrl":"https://doi.org/10.1117/12.2263972","url":null,"abstract":"A few-mode microfiber knot resonator (FM-MKR) incorporating a polyvinyl alcohol (PVA) is investigated for measurement of relative humidity (RH). Two modes, such as HE11 and HE12, are excited and interfered in a nonadiabatically tapered structure of the single-mode fiber (SMF). After making a tie with the few-mode microfiber, the FM-MKR is fabricated. In the FM-MKR, two modes, such as HE11 and HE12, must be circulated within the optical knot and cross-coupled independently with a phase delay. By optimizing the diameter of the microfiber, the difference of group effective refractive indices between two modes is dramatically suppressed resulting in the improvement of RH sensitivity of the proposed FM-MKR.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121795600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. F. Shirazi, R. E. Wijesinghe, N. Ravichandran, Pilun Kim, Mansik Jeon, Jeehyun Kim
The conventional Fourier domain optical coherence tomography system requires single scanner for two dimensional cross-sectional image and two scanners for volumetric image. Parallel spectral domain optical coherence tomography has advantage of single scanner for volumetric image, while two dimensional cross-sectional images are obtained by parallel acquisition of illuminated line on sample using area camera. In this study, the industrial inspection of optical thin film on touch screen panels was demonstrated using parallel spectral domain optical coherence tomography. The cross-sectional and volumetric images were acquired to detect the internal sub layer defects in optical thin film which are difficult to observe using visual or machine vision based inspection methods. The results indicate the possible application of the proposed system in touch screen panels inspection for quality assurance of product at consumer end.
{"title":"Optical thin film inspection using parallel spectral domain optical coherence tomography","authors":"M. F. Shirazi, R. E. Wijesinghe, N. Ravichandran, Pilun Kim, Mansik Jeon, Jeehyun Kim","doi":"10.1117/12.2267395","DOIUrl":"https://doi.org/10.1117/12.2267395","url":null,"abstract":"The conventional Fourier domain optical coherence tomography system requires single scanner for two dimensional cross-sectional image and two scanners for volumetric image. Parallel spectral domain optical coherence tomography has advantage of single scanner for volumetric image, while two dimensional cross-sectional images are obtained by parallel acquisition of illuminated line on sample using area camera. In this study, the industrial inspection of optical thin film on touch screen panels was demonstrated using parallel spectral domain optical coherence tomography. The cross-sectional and volumetric images were acquired to detect the internal sub layer defects in optical thin film which are difficult to observe using visual or machine vision based inspection methods. The results indicate the possible application of the proposed system in touch screen panels inspection for quality assurance of product at consumer end.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124529341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Warren-Smith, L. Nguyen, H. Ebendorff‐Heidepriem, T. Monro
We present recent developments in high temperature sensing using single material silica optical fibers. By using a single material fiber, in this case a suspended-core fiber, we avoid effects due to dopant diffusion at high temperature. This allows the measurement of temperatures up to the dilatometric softening temperature at approximately 1300°C. We demonstrate and compare high temperature sensing in two configurations. The first exploits a small section of single material fiber spliced onto a length of conventional single mode fiber, which operates through multimode interference. The second utilizes a type 11 fiber Bragg grating written via femtosecond laser ablation.
{"title":"High temperature sensing with single material silica optical fibers","authors":"S. Warren-Smith, L. Nguyen, H. Ebendorff‐Heidepriem, T. Monro","doi":"10.1117/12.2265205","DOIUrl":"https://doi.org/10.1117/12.2265205","url":null,"abstract":"We present recent developments in high temperature sensing using single material silica optical fibers. By using a single material fiber, in this case a suspended-core fiber, we avoid effects due to dopant diffusion at high temperature. This allows the measurement of temperatures up to the dilatometric softening temperature at approximately 1300°C. We demonstrate and compare high temperature sensing in two configurations. The first exploits a small section of single material fiber spliced onto a length of conventional single mode fiber, which operates through multimode interference. The second utilizes a type 11 fiber Bragg grating written via femtosecond laser ablation.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130923753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zeng Xiong, Ciming Zhou, Huiyong Guo, D. Fan, Y. Ou, Yi Liu, Chunran Sun, L. Qian
We demonstrate a high spatial resolution multiplexing scheme for fiber Bragg grating (FBG) sensors based on single-arm frequency-shifted interferometry (SA-FSI). The SA-FSI system uses an incoherent broadband source, a slow detector, and an electro-optic modulator (EOM). By sweeping the frequency of EOM and taking the fast Fourier transform (FFT) of the interference signal, we resolved the locations of FBGs distributed both in parallel and in series along fiber links despite their reflection spectral overlap. Eighteen weak FBGs (∼5% reflectivity) separated by ∼0.1 m were clearly resolved experimentally, sweeping EOM modulation frequency in the range of 2–11 GHz.
{"title":"High spatial resolution multiplexing of fiber Bragg gratings using single-arm frequency-shifted interferometry","authors":"Zeng Xiong, Ciming Zhou, Huiyong Guo, D. Fan, Y. Ou, Yi Liu, Chunran Sun, L. Qian","doi":"10.1117/12.2265331","DOIUrl":"https://doi.org/10.1117/12.2265331","url":null,"abstract":"We demonstrate a high spatial resolution multiplexing scheme for fiber Bragg grating (FBG) sensors based on single-arm frequency-shifted interferometry (SA-FSI). The SA-FSI system uses an incoherent broadband source, a slow detector, and an electro-optic modulator (EOM). By sweeping the frequency of EOM and taking the fast Fourier transform (FFT) of the interference signal, we resolved the locations of FBGs distributed both in parallel and in series along fiber links despite their reflection spectral overlap. Eighteen weak FBGs (∼5% reflectivity) separated by ∼0.1 m were clearly resolved experimentally, sweeping EOM modulation frequency in the range of 2–11 GHz.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131378491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Md. Arafat Hossain, J. Canning, K. Cook, Sandra Ast, A. Jamalipour
Degradation of olive oil under light and heat are analysed using an optical fibre based low-cost portable smartphone spectrofluorimeter. Visible fluorescence bands associated with phenolic acids, vitamins and chlorophyll centred at λ ∼ 452, 525 and 670 nm respectively are generated using near-UV excitation (LED λex ∼ 370 nm), of extra virgin olive oil are degraded more likely than refined olive oil under light and heat exposure. Packaging is shown to be critical when assessing the origin of degradation.
{"title":"Photo- and thermal degradation of olive oil measured using an optical fibre smartphone spectrofluorimeter","authors":"Md. Arafat Hossain, J. Canning, K. Cook, Sandra Ast, A. Jamalipour","doi":"10.1117/12.2265580","DOIUrl":"https://doi.org/10.1117/12.2265580","url":null,"abstract":"Degradation of olive oil under light and heat are analysed using an optical fibre based low-cost portable smartphone spectrofluorimeter. Visible fluorescence bands associated with phenolic acids, vitamins and chlorophyll centred at λ ∼ 452, 525 and 670 nm respectively are generated using near-UV excitation (LED λex ∼ 370 nm), of extra virgin olive oil are degraded more likely than refined olive oil under light and heat exposure. Packaging is shown to be critical when assessing the origin of degradation.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128740239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Desmarchelier, R. Cotillard, N. Roussel, S. Armiroli, G. Laffont
This paper presents the development of a CO2 laser-based heating system to simulate fast thermal phenomena on high temperature resistant FBGs dedicated to high temperature profiles monitoring within components exposed to hot plasma inside Tokamak. We have demonstrated the reliability of two optical fiber based sensing techniques to control spatial and temporal annealing measurement during high and fast thermal process.
{"title":"Monitoring of single-mode fiber laser heating using Rayleigh scattering and 1st order fs-PbP fiber Bragg Grating","authors":"R. Desmarchelier, R. Cotillard, N. Roussel, S. Armiroli, G. Laffont","doi":"10.1117/12.2265795","DOIUrl":"https://doi.org/10.1117/12.2265795","url":null,"abstract":"This paper presents the development of a CO2 laser-based heating system to simulate fast thermal phenomena on high temperature resistant FBGs dedicated to high temperature profiles monitoring within components exposed to hot plasma inside Tokamak. We have demonstrated the reliability of two optical fiber based sensing techniques to control spatial and temporal annealing measurement during high and fast thermal process.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122510842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Zibaii, H. Latifi, F. Karami, Abdolaziz Ronaghi, Sara Chavoshi Nejad, L. Dargahi
This work reports on the development of an optical fiber sensor based fiber Bragg Grating (FBG) probe for in vivo measurements of brain temperature. The major goal of this work is to demonstrate that the changes in brain temperature induced by drugs is an important reality, which could provide new valuable information on the mechanisms of drug action and open new therapeutic approaches. This probe can be interrogated using a portable optical measurement setup, allowing for measurements to be performed outside of standard optical laboratories.
{"title":"In vivo brain temperature measurements based on fiber optic Bragg grating","authors":"M. Zibaii, H. Latifi, F. Karami, Abdolaziz Ronaghi, Sara Chavoshi Nejad, L. Dargahi","doi":"10.1117/12.2265607","DOIUrl":"https://doi.org/10.1117/12.2265607","url":null,"abstract":"This work reports on the development of an optical fiber sensor based fiber Bragg Grating (FBG) probe for in vivo measurements of brain temperature. The major goal of this work is to demonstrate that the changes in brain temperature induced by drugs is an important reality, which could provide new valuable information on the mechanisms of drug action and open new therapeutic approaches. This probe can be interrogated using a portable optical measurement setup, allowing for measurements to be performed outside of standard optical laboratories.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"8 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120863523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Youngmin Kim, S. Ju, Seongmook Jeong, Seung Ho Lee, Youngwoong Kim, W. Han
Effect of fluorine (F) doping in the core of a birefringent photonic crystal fiber (PCF) on sensing capability of temperature and strain was investigated by using Sagnac loop interferometry. The birefringence of the F-doped PCF was measured to be 1.56χ10−4 at 1550 nm and the temperature and the strain sensitivities of the F-doped PCF were found to increase from −9.6 pm/°C/m to −34 pm/°C/m and from 3.5 pm/με to 6.3 pm/με, respectively.
{"title":"Effect of F doping in the core of a birefringent photonic crystal fiber on sensing capability of temperature and strain sensors","authors":"Youngmin Kim, S. Ju, Seongmook Jeong, Seung Ho Lee, Youngwoong Kim, W. Han","doi":"10.1117/12.2265539","DOIUrl":"https://doi.org/10.1117/12.2265539","url":null,"abstract":"Effect of fluorine (F) doping in the core of a birefringent photonic crystal fiber (PCF) on sensing capability of temperature and strain was investigated by using Sagnac loop interferometry. The birefringence of the F-doped PCF was measured to be 1.56χ10<sup>−4</sup> at 1550 nm and the temperature and the strain sensitivities of the F-doped PCF were found to increase from −9.6 pm/°C/m to −34 pm/°C/m and from 3.5 pm/με to 6.3 pm/με, respectively.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122305401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Ouyang, Jing Kong, Yimin Xu, Ai Zhou, Libo Yuan
A simultaneous temperature and bend sensor based on an eccentric core fiber Bragg grating (ECFBG) cascaded with a Fabry-Perot cavity is presented and demonstrated. The hybrid structure is composed of a piece of hollow core fiber, which is sandwiched in between a piece of multimode fiber and an ECFBG. The curvature sensitivities of the ECFBG at the two opposite most sensitive directions are 52.2 pm/m−1 and −51.7 pm/m−1 respectively, and those of the FPI are 58.6pm/m−1 and −61.4 pm/m−1, respectively. The temperature sensitivities of the two parts are very different. The temperature sensitivity of the ECFBG is 10.3 pm/°c, and that of the FPI is as low as 0.7 pm/°c.
{"title":"Simultaneous measurement of temperature and bend by using an eccentric core fiber Bragg grating cascaded with a Fabry-Perot cavity","authors":"Y. Ouyang, Jing Kong, Yimin Xu, Ai Zhou, Libo Yuan","doi":"10.1117/12.2264894","DOIUrl":"https://doi.org/10.1117/12.2264894","url":null,"abstract":"A simultaneous temperature and bend sensor based on an eccentric core fiber Bragg grating (ECFBG) cascaded with a Fabry-Perot cavity is presented and demonstrated. The hybrid structure is composed of a piece of hollow core fiber, which is sandwiched in between a piece of multimode fiber and an ECFBG. The curvature sensitivities of the ECFBG at the two opposite most sensitive directions are 52.2 pm/m<sup>−1</sup> and −51.7 pm/m<sup>−1</sup> respectively, and those of the FPI are 58.6pm/m<sup>−1</sup> and −61.4 pm/m<sup>−1</sup>, respectively. The temperature sensitivities of the two parts are very different. The temperature sensitivity of the ECFBG is 10.3 pm/°c, and that of the FPI is as low as 0.7 pm/°c.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126693602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hyeonsoo Park, Kyookeun Lee, Jeong-Geun Yun, Chulsoo Choi, Hwi Kim, Byoungho Lee
We numerically analyzed the refractive index sensing performance of the two-dimensional array of plasmonic V-shaped grooves. The structural parameters are optimized to show a sharp and large reflectance dip with desired sensing region (n=1.33). Acquiring the sensitivity of the environmental refractive index as 400 nm/RIU in the visible region, FWHM of the dip is ∼5 nm. It shows that the proposed structure has extreme value of quality factor and good extinction ratio. The localized mode has the hot spot at the bottom of the grooves so that localized sensing based on magnetic field enhancement is possible. Moreover, the localized mode is dependent on the tapered angle of the grooves, not the opening ratio. The performance of the dual V-shaped grooves is also discussed. The array of the closely located grooves has nearly identical reflectance spectra but a moderate amount of dip shift exists. As well as obtaining refractive index sensing by this configuration, magnetic field hot spot generation by coherent excitation can be applied to highly localized sensing and enhancing nonlinear processes.
{"title":"Two-dimensional array of plasmonic V-shaped grooves for sensing applications","authors":"Hyeonsoo Park, Kyookeun Lee, Jeong-Geun Yun, Chulsoo Choi, Hwi Kim, Byoungho Lee","doi":"10.1117/12.2266610","DOIUrl":"https://doi.org/10.1117/12.2266610","url":null,"abstract":"We numerically analyzed the refractive index sensing performance of the two-dimensional array of plasmonic V-shaped grooves. The structural parameters are optimized to show a sharp and large reflectance dip with desired sensing region (n=1.33). Acquiring the sensitivity of the environmental refractive index as 400 nm/RIU in the visible region, FWHM of the dip is ∼5 nm. It shows that the proposed structure has extreme value of quality factor and good extinction ratio. The localized mode has the hot spot at the bottom of the grooves so that localized sensing based on magnetic field enhancement is possible. Moreover, the localized mode is dependent on the tapered angle of the grooves, not the opening ratio. The performance of the dual V-shaped grooves is also discussed. The array of the closely located grooves has nearly identical reflectance spectra but a moderate amount of dip shift exists. As well as obtaining refractive index sensing by this configuration, magnetic field hot spot generation by coherent excitation can be applied to highly localized sensing and enhancing nonlinear processes.","PeriodicalId":198716,"journal":{"name":"2017 25th Optical Fiber Sensors Conference (OFS)","volume":"2016 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127526871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}