316 Hits in 5.3 sec

Rayleigh scattering in few-mode optical fibers

Zhen Wang, Hao Wu, Xiaolong Hu, Ningbo Zhao, Qi Mo, Guifang Li
2016 Scientific Reports  
Rayleigh scattering has been studied in single-and multi-mode optical fibers. And the relevant theories are well established.  ...  Rayleigh backscattering not only sets the intrinsic loss limit for FMFs but also provides the theoretical foundation for few-mode optical time-domain reflectometry, which can be used to probe perturbationinduced  ...  Hao Wu from Yokogawa Shanghai Trading CO., LTD. for lending us the OTDR with a 50-dB dynamic range.  ... 
doi:10.1038/srep35844 pmid:27775003 pmcid:PMC5075780 fatcat:m2t5w24fzbblfcfynfrrimpgwe

Frequency scanned phase sensitive optical time-domain reflectometry interrogation in multimode optical fibers

K. Markiewicz, J. Kaczorowski, Z. Yang, L. Szostkiewicz, A. Dominguez-Lopez, K. Wilczynski, M. Napierala, T. Nasilowski, L. Thévenaz
2020 APL Photonics  
Large differences in the propagation constant and the spatial distribution of distinct modes degrade the performance of phase-sensitive optical time-domain reflectometry measurements.  ...  In this work, we present a new realization of a coherent time-domain interrogation technique using single-mode operation in multimode fibers.  ...  coupling between different mode groups is negligible. 18 At each point, part of the light is Rayleigh-backscattered into all modes propagating inside the fiber under test. 19 The returning signal  ... 
doi:10.1063/1.5138728 fatcat:bby5dgp4jzbozpwdirhr4do5ke

Distributed Optical Fiber Sensing Based on Rayleigh Scattering

Luca Palmieri
2013 The Open Optics Journal  
For a given optical frequency, Rayleigh-based sensors exploit the three main properties of light: intensity, phase and polarization.  ...  Optical fiber sensors offer unprecedented features, the most unique of which is the ability of monitoring variations of the observed physical field with spatial continuity along the fiber.  ...  Partial financial support from Fondazione Cassa di Risparmio di Padova e Rovigo, and from the Italian Ministry of Foreign Affairs (Direzione Generale per la Promozione del Sistema Paese) is acknowledged  ... 
doi:10.2174/1874328501307010104 fatcat:pvw7kc6dwfb2rhe5pk4f24lgri

optical time domain reflectometry [chapter]

Martin H. Weik
2000 Computer Science and Communications Dictionary  
It predicts system performance for measurements of fiber breaks and discontinuities, fiber attenuation, and fiber dispersion.  ...  Two systems are shown to be needed for the two common types of future fiber syst ems.  ...  Godfrey of Opto-Electronics Ltd. for his supervision and encouragement. Th &nks also to Van Tzannidakis and everyone else at Opto for helpful suggestions. --  ... 
doi:10.1007/1-4020-0613-6_13168 fatcat:4zjweh4ry5h7lcnogdjchjqt2q

Review of Fiber Optic Sensors for Structural Fire Engineering

Yi Bao, Ying Huang, Matthew Hoehler, Genda Chen
2019 Sensors  
Fiber optic sensors, which are based on light signals, solve many of the problems of monitoring structures in high temperature environments; however, they present their own challenges.  ...  This paper, which is intended for structural engineers new to fiber optic sensors, reviews various fiber optic sensors that have been used to make measurements in structure fires, including the sensing  ...  Multi-mode fibers have a larger diameter core that allows multiple propagation modes of the guided wave ( Figure 1b) .  ... 
doi:10.3390/s19040877 fatcat:tsxsom5q2vfihbkdkv77c227cm

Polymer optical fiber sensors—a review

Kara Peters
2010 Smart materials and structures (Print)  
Recent demonstrations of multi-mode POF sensors in structural applications based on new interrogation methods, including backscattering and time-of-flight measurements, are outlined.  ...  The recent emergence of single-mode POFs has enabled high precision, large deformation optical fiber sensors.  ...  Step index profiles have particularly high intermodal dispersion, therefore graded index profile fibers, which can lower the intermodal dispersion by a few orders of magnitude, are often used for longer  ... 
doi:10.1088/0964-1726/20/1/013002 fatcat:mbe27y5carhtlcj4kyu65fdffe

Recent Progress in Distributed Fiber Optic Sensors

Xiaoyi Bao, Liang Chen
2012 Sensors  
By detecting changes in the amplitude, frequency and phase of light scattered along a fiber, one can realize a distributed fiber sensor for measuring localized temperature, strain, vibration and birefringence  ...  With coherent detection of the scattered light one can observe changes in birefringence and beat length for fibers and devices.  ...  Acknowledgements The authors acknowledge the contributions of many of their graduate students, postdoctoral fellows and research associates described in part in this review and the supports of the National  ... 
doi:10.3390/s120708601 pmid:23012508 pmcid:PMC3444066 fatcat:ga6z5qzkcrdbflj42zef3vmkiu

Fiber-integrated Brillouin microspectroscopy: Towards Brillouin endoscopy

Irina V. Kabakova, YuChen Xiang, Carl Paterson, Peter Török
2017 Journal of Innovative Optical Health Sciences  
Measurements of Brillouin spectra in test liquids (water, ethanol and glycerol) are demonstrated using the dual-¯ber endoscope and its performance is analyzed numerically with the help of a beam propagation  ...  Although the principles of BI imply its compatibility with in vivo and in situ measurements, the integration of BI with a°exible catheter, capable of reaching the region of interest within the body, is  ...  maximum of 3 m (equal to the modē eld diameter of the SMF) and use the beam propagation method to study numerically the light propagation in our¯ber probes. 26 Since the¯ber and the lens have cylindrical  ... 
doi:10.1142/s1793545817420020 fatcat:tdlja735mrdwzifsohhp54bgre

Recent Advances in Brillouin Optical Time Domain Reflectometry

Qing Bai, Qinglin Wang, Dong Wang, Yu Wang, Yan Gao, Hongjuan Zhang, Mingjiang Zhang, Baoquan Jin
2019 Sensors  
fiber, photonic crystal fiber, few-mode fiber and other special fibers.  ...  Firstly, the recent advances in improving the performance of BOTDRs are summarized, such as spatial resolution, signal-to-noise ratio and measurement accuracy, measurement speed, cross sensitivity and  ...  In 2017, Zhou et al. proposed a graded-index few-mode fiber (GI-FMF) with the radius of 5 µm and the maximum GeO 2 -doping concentration of 10%, which supported the two guided modes of LP 01 and LP 11  ... 
doi:10.3390/s19081862 fatcat:nmif4euacnbjnip2ynemzzguiq

Recent Progress of Fiber-Optic Sensors for the Structural Health Monitoring of Civil Infrastructure

Tiange Wu, Guowei Liu, Shenggui Fu, Fei Xing
2020 Sensors  
The purpose of this review article is devoted to presenting a summary of the basic principles of various fiber-optic sensors, classification and principles of FOS, typical and functional fiber-optic sensors  ...  number of innovative sensing systems have been exploited in the civil engineering for SHM used in projects (including buildings, bridges, tunnels, etc.).  ...  ∆β is the propagation constant difference of the coupled mode, Λ is the grating period, n is the effective refractive index, λ is the resonance wavelength.  ... 
doi:10.3390/s20164517 pmid:32806746 fatcat:hv7qxmtnlnbonjub6hpp66bzm4

Advanced Spatial-Division Multiplexed Measurement Systems Propositions—From Telecommunication to Sensing Applications: A Review

Yi Weng, Ezra Ip, Zhongqi Pan, Ting Wang
2016 Sensors  
The key advantages of implementing SDM techniques in optical measurement systems include the multi-parameter discriminative capability and accuracy improvement.  ...  with many independent cores to pass through, and mode-division multiplexing (MDM) using multimode fibers (MMF) or few-mode fibers (FMF) whereas one single-core large-area fiber allows a number of spatial  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s16091387 pmid:27589754 pmcid:PMC5038665 fatcat:veuiynqk7nb43cuq2xl3tjov2q

Brillouin Scattering in Polymer Optical Fibers: Fundamental Properties and Potential Use in Sensors

Yosuke Mizuno, Kentaro Nakamura
2011 Polymers  
These properties were compared with those of silica-based graded-index multi-mode fibers. We also investigated the BFS dependences on strain and temperature.  ...  We review the fundamental properties of Brillouin scattering in a perfluorinated graded-index polymer optical fiber (PFGI-POF) with 120 m core diameter.  ...  Acknowledgements We are indebted to Nishiyama and Uenohara of Tokyo Institute of Technology, Japan, for lending us their high-power EDFAs. Y.  ... 
doi:10.3390/polym3020886 fatcat:aem2p2uxwff2niimutxdspei7q

Analytical Modeling Tool for Design of Hydrocarbon Sensitive Optical Fibers

Khalil Al Handawi, Nader Vahdati, Oleg Shiryayev, Lydia Lawand
2017 Sensors  
A Refractive Index (RI) change occurs in the polymer cladding causing a loss in intensity of a traveling light pulse due to a reduction in the fiber's modal capacity.  ...  Fiber optic sensors with polymer claddings provide a means of detecting contact with hydrocarbons.  ...  The spectral profile of the backscattered light pulse may be used to infer temperature and strain effects by virtue of Rayleigh, Brillouin or Raman scattering [6, 12] .  ... 
doi:10.3390/s17102227 pmid:28956847 pmcid:PMC5677271 fatcat:5ohpyqseuza57m7zafm63lq6ka

A Special Fiber Optic Sensor for Measuring Wheel Loads of Vehicles on Highways

Ramesh Malla, Amlan Sen, Norman Garrick
2008 Sensors  
The fiber used has a unique design with two concentric light guiding regions of different effective optical path lengths, which has the potential to enable direct measurement of magnitudes as well as locations  ...  The results also showed a good correlation between the time delay between the inner and outer core light pulses and the distance of the applied load as measured from the output end of the fiber.  ...  The views expressed in this paper are those of the authors.  ... 
doi:10.3390/s8042551 pmid:27879835 pmcid:PMC3673431 fatcat:7vhelbonm5hnxn6jgqffzgqkla

24 km High-Performance Raman Distributed Temperature Sensing Using Low Water Peak Fiber and Optimized Denoising Neural Network

Hao Wu, Haoze Du, Can Zhao, Ming Tang
2022 Sensors  
Raman distributed optical fiber temperature sensing (RDTS) has been extensively studied for decades because it enables accurate temperature measurements over long distances.  ...  The signal-to-noise ratio (SNR) is the main factor limiting the sensing distance and temperature accuracy of RDTS.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s22062139 pmid:35336310 pmcid:PMC8949466 fatcat:5oqed6ozmnhdpl5d62k3lx5tdy
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