Optical Fiber Interferometers Based on Arc-Induced Long Period Gratings at INESC TEC
Sensors, 2021 In this work, we review the most important achievements of an INESC TEC long-period-grating-based fiber optic Michelson and Mach–Zehnder configuration modal interferometer with coherence addressing and heterodyne interrogation as a sensing structure for ...
Paulo Caldas, Gaspar Rego
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Properties of length-apodized phase-shifted lpgs operating at the phase matching turning point [PDF]
, 2012 The characteristics of length-apodized phase-shifted fiber optic long period gratings with full and partial nanostructured coatings have been explored theoretically and experimentally.
Tatam, Ralph P. +2 more
core +1 more source
Implementation of vectorial bend sensors using long-period gratings UV-inscribed in special shape fibres [PDF]
, 2004 We report the implementation of vector bending sensors using long-period gratings (LPGs) UV-inscribed in flat-clad, four-core and D-shaped fibres. Our experiments reveal a strong fibre-orientation dependence of the spectral response when such LPGs are ...
Flockhart, G +8 more
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Long-Period Fiber Gratings in Active Fibers
, 2013 Traditionally, long period fiber gratings (LPG) are made in passive optical fibers that have negligible loss. However, loss or gain that can be controlled via optical pumping adds a new degree of freedom and - as will be shown in this chapter - brings many new and interesting properties.
David Krmak +2 more
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Review of long period fiber gratings written by CO2 laser
, 2010 This paper presents a systematic review of long period fiber gratings (LPFGs) written by the CO2 laser irradiation technique. First, various fabrication techniques based on CO2 laser irradiations are demonstrated to write LPFGs in different types of ...
Yiping Wang, Wang, Yiping
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Multiplexing of fiber-optic long-period grating-based interferometric sensors [PDF]
, 2007 Two long-period gratings (LPGs) fabricated in series in an optical fiber form a Mach-Zehnder interferometer, producing a sinusoidal channelled spectrum within the characteristic LPG attenuation bands, which has the appearance of an interference fringe ...
Tatam, Ralph P. +2 more
core +1 more source
Proceedings, 2019 Optical fiber sensors based on in-fiber Long Period Gratings (LPG) have attracted considerableinterest in the context of environmental, chemical and biochemical sensing. [...]
Cosimo Trono +2 more
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Dissimilar-fiber long-period fiber gratings: concept and demonstration
Applied Optics, 2017 A new type of long-period fiber grating structure that contains dissimilar fiber types is proposed. This dissimilar-fiber long-period fiber grating (DF-LPFG) structure is fabricated by splicing together subperiod sections of dissimilar fiber types. Due to the large index differences that can exist between various fiber types, the resulting DF-LPFGs can
Pengfei, Wang, Thomas K, Gaylord
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Efficient large-scale multiplexing of fiber Bragg grating and fiber Fabry-Perot sensors for structural health monitoring applications [PDF]
, 2006 Fiber Bragg gratings have been demonstrated as a versatile sensor for structural health monitoring. We present an efficient and cost effective multiplexing method for fiber Bragg grating and fiber Fabry-Perot sensors based on a broadband mode-locked ...
Kirkendall, C. K. +2 more
core +4 more sources
Long Period Fiber Gratings Inscribed With an Improved Two-Dimensional Scanning Technique
IEEE Photonics Journal, 2014 We demonstrated a promising CO2 laser irradiation system based on an improved 2-D scanning technique. Such a system could be used to inscribe high-quality long period fiber gratings (LPFGs) with good reproducibility of grating inscription, which ...
Xiaoyong Zhong +7 more
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