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Showing 1 to 20 of 27 for “"Fiber Bragg gratings"”.
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Fiber Bragg Gratings Strain Sensors for Railway Applications
Fiber optical sensors have played an important role in applications for monitoring the health of civil infrastructures, such as bridges, oil rigs, and railroads. Due to the reduction in cost of fiber-optic components and systems, fiber optical sensors have been studied extensively for their higher …
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Fully Distributed Multi-parameter Sensors Based on Acoustic Fiber Bragg Gratings
… based on intrinsic scatterings in optical fibers. They demonstrate long sensing span, but their limited applicable parameters (temperature and strain) and costly interrogation systems have prevented their widespread applications. A novel concept of acoustic fiber Bragg grating (AFBG) is …
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High-Speed Quasi-Distributed Optical Fiber Sensing Based on Ultra-Weak Fiber Bragg Gratings
Invention of silica based optical fiber not only led to revolution in communication but also provided fundamental basis for many research areas. One example area is distributed optical fiber sensing, which has been attracting research interests for decades. Optical fiber sensors are immune to …
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A Quasi-distributed Sensing Network Based on Wavelength-Scanning Time-division Multiplexed Fiber Bragg Gratings
… capability of operation in harsh environments. Fiber Bragg grating (FBG) has attracted considerable interest for this application because of its compactness, electromagnetic immunity, and excellent multiplexing capability. Several FBG multiplexing techniques have been developed to increase the …
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Photosensitivity and Photodarkening of UV-induced Phosphate Glass Fiber Bragg Gratings and Application in Short Fiber Lasers
Phosphate glass fiber is an ideal choice for building compact high gain fiber lasers, as the fiber can host high concentrations of rare earth ions. However, the low photosensitivity of phosphate glass fibers prevents the integration of UV-written intra-core fiber Bragg gratings (FBGs) into the …
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Developing a Multi-axis Femtosecond Laser Micromachining Platform for Laser Induced Refractive Index Modification: Fiber Bragg Gratings, Waveguides, and Beyond
… capabilities were demonstrated by inscribing Fiber Bragg Gratings and waveguides using a 1040 nm laser, extended to 750 nm and 1260 nm with an Optical Parametric Amplifier. Precise control over FBG pitch and length were achieved, with results showcasing strong refractive index modifications. …
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Desenvolvimento de um sensor de fibras ópticas de sulfeto de hidrogênio baseado em redes de Bragg e Filmes Finos
… of hydrogen sulfide gas, using a sensor based on fiber Bragg gratings, known as optical fiber sensorsand thin films. To carry out the measures fiber Bragg gratings-based sensing methodologies and deposition of nanometric thin films sensitive to the gas in question will be employed. Sensitive films …
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Optical Coherence Sensors in Multimode Fibers
Optical fiber sensors are widely applied in modern sensing systems. Taking advantage of the high sensitivity of optical interference, optical coherence fiber sensors, such as fiber Bragg gratings (FBGs) and Fabry-Perot interferometers (FPIs), have been investigated intensively and utilized broadly …
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Femtosecond-Laser-Enabled Fiber-Optic Interferometric Devices
… truly three-dimensional fabrication. Moreover, fiber-optic sensors have demonstrated distinct advantages over traditional electrical sensors such as the immunity to electromagnetic interference, miniature footprint, robust performance, and high sensitivity. Therefore, the marriage between …
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Contribución al análisis y procesado de señales fotónicas multibanda
… planos (Arrayed Waveguide Gratings, AWGs) y las redes de Bragg en fibra óptica (Fiber Bragg Gratings, FBGs). Los AWGs son unos dispositivos con múltiples puertos de entrada y de salida. El diseño de los AWG es tal que la señal de un puerto a la entrada se dirige a un puerto …
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Compensação de temperatura para sensores de corrente elétrica baseados em redes de Bragg em fibras ópticas
… for electrical current sensors based on fiber Bragg gratings using the twin gratings technique. The measurement of electric current by opto-mechanical sensors is very well described in the literature, as well as techniques that propose the compensation of thermal variation effects on the …
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Structural Monitoring With Fiber Bragg Grating Strain Sensor Array and Optical Frequency Domain Reflectometry
… Domain Reflectometry (C-OFDR) to interrogate Fiber Bragg Grating Arrays (FBGA) have shown promise in its use in infrastructure health monitoring systems. In this work, the modeling, design, simulation, fabrication, calibration, and testing of a three-element, 15.3 cm fiber Bragg grating strain …
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Bragg grating sensor interrogation using in-line, dual-mode fiber demodulators
Optical fiber Bragg gratings, first demonstrated by Hill in 1978 [1], will see increasing deployment as sensors in smart structure applications due to their minimal insertion loss and small profile. Bragg grating sensors provide narrowband reflections from a periodic index discontinuity. Strain and …
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Development of a Miniature, Semi-Distributed Sapphire Fiber Optic Thermometer for Harsh and High Temperature Environments
Fiber optic temperature sensing has become a well-defined field in the past few decades [1] through the use of Fiber Bragg Gratings, Fabry-Perot interferometry, and pyrometry, to list several techniques in use today. The use of fiber optics offers significant advantages over electronic sensing in …
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Investigation of code reconfigurable fibre Bragg gratings for Optical Code Division Multiple Access (OCDMA) and Optical Packet Switching (OPS) Networks
… packet switching nodes based on fibre Bragg grating (FBG) technology. My research work involves characterizing the performance of various gratings, specifically high reflectivity, short chip duration, long code sequences, multiple phase level and tunable superstructured fiber Bragg …
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Sapphire Fiber Based Sensing Technologies for High Temperature Applications
Sapphire fiber has been studied intensively for harsh environment sensing in the past two decades due to its supreme mechanical, physical and optical properties. It is by far the most reported and likely the best optical fiber based sensing technology for sensing applications in temperature beyond …
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All-optical ultrafast switches based on thin film coated-tilted fiber Bragg grating
… networks. Switches based on tilted fiber Bragg gratings (TFBG), coupling the forward propagation core mode to hundreds of discrete backward propagation cladding modes provide a novel platform for light-matter interaction by modulation of material permittivity via the evanescent field …
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Optical fiber temperature sensor based on fiber bragg grating
It is important to study optical fiber temperature sensor based on fiber Bragg Grating. The Fiber Bragg grating sensors can offer highly sensitive, cost effective solutions for optical sensing. While fiber Bragg gratings have been implemented in various sensing applications over the past few …
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Intrinsic Fabry-Perot Interferometric Fiber Sensor Based on Ultra-Short Bragg Gratings for Quasi-Distributed Strain and Temperature Measurements
… using conventional electrical strain sensors. Fiber optic sensors provide an excellent opportunity to fulfill this need due to their capability to multiplex many sensors along a single fiber cable. Numerous research studies have been conducted in past decades to increase the number of sensors …
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Design of graphical user interface for multiuser SAC-OCDMA performance analysis
… of the decoder which is implemented using fiber Bragg gratings (FBGs) for the three detection techniques using numerical analysis have been developed for the GUI. The numerical analysis is based on the SNR and BER for the system in the presence of thermal noise, shot noise and phase induced …
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