ZrO2, CuO, Al2O3 and SiO2 mixed nanopowder was used to coat the head of sapphire single crystal fiber for improving the properties of high-temperature single crystal fiber sensor. The result indicates that the head co...ZrO2, CuO, Al2O3 and SiO2 mixed nanopowder was used to coat the head of sapphire single crystal fiber for improving the properties of high-temperature single crystal fiber sensor. The result indicates that the head coated with above mixed nanopowder shows better optical stability,shorter response time and higher thermal shock resistance, in comparison with the head coated with coarse-grained particles with the same chemical展开更多
An extended-life and ultra-low oxygen sensor has been fabricated by using polycrystalline Caβ″/β/α-Al2O3 as a solid electrolyte. Five reference electrodes CaO+O2, Caβ″/β/α-Al2O3 (powder)+O2,Cr+Cr2O3, Nb+NbO an...An extended-life and ultra-low oxygen sensor has been fabricated by using polycrystalline Caβ″/β/α-Al2O3 as a solid electrolyte. Five reference electrodes CaO+O2, Caβ″/β/α-Al2O3 (powder)+O2,Cr+Cr2O3, Nb+NbO and Mo+MoO2 were tested in order to select a better reference electrode for this sensor. The limit of determining oxygen activity and the extended-life of the sensor were also tested in this study.展开更多
A high sensitivity D-shaped hole double-cladding fiber temperature sensor based on surface plasmon resonance(SPR)is designed and investigated by a full-vector finite element method.Within the D-shaped hole doublecladd...A high sensitivity D-shaped hole double-cladding fiber temperature sensor based on surface plasmon resonance(SPR)is designed and investigated by a full-vector finite element method.Within the D-shaped hole doublecladding fiber,the hollow D-section is coated with gold film and then injected in a high thermo-optic coefficient liquid to realize the high temperature sensitivity for the fiber SPR temperature sensor.The numerical simulation results show that the peaking loss of the D-shaped hole double-cladding fiber SPR is hugely influenced by the distance between the D-shaped hole and fiber core and by the thickness of the gold film,but the temperature sensitivity is almost insensitive to the above parameters.When the thermo-optic coefficient is -2.8×10^(-4)∕℃,the thickness of the gold film is 47 nm,and the distance between the D-shaped hole and fiber core is 5μm,the temperature sensitivity of the D-shaped hole fiber SPR sensor can reach to -3.635 nm∕℃.展开更多
In this paper, the spectrum shift properties of the center reflection wavelength detected to be based on the FBG sensor with ambient temperature change. The basic theoretical methods and numerical simulation for the s...In this paper, the spectrum shift properties of the center reflection wavelength detected to be based on the FBG sensor with ambient temperature change. The basic theoretical methods and numerical simulation for the spectral properties of uniform Bragg grating is analyzed by using coupling mode theory which is optical properties of high sensitivity fiber Bragg grating on temperature sensor in accordance with experiment.展开更多
Fiber Bragg grating(FBG)is the most widely used optical fiber sensor due to its compact size,high sensitivity,and easiness for multiplexing.Conventional FBGs fabricated by using an ultraviolet(UV)laser phase-mask meth...Fiber Bragg grating(FBG)is the most widely used optical fiber sensor due to its compact size,high sensitivity,and easiness for multiplexing.Conventional FBGs fabricated by using an ultraviolet(UV)laser phase-mask method require the sensitization of the optical fiber and could not be used at high temperatures.Recently,the fabrication of FBGs by using a femtosecond laser has attracted extensive interests due to its excellent flexibility in creating FBGs array or special FBGs with complex spectra.The femtosecond laser could also be used for inscribing various FBGs on almost all fiber types,even fibers without any photosensitivity.Such femtosecond-laser-induced FBGs exhibit excellent thermal stability,which is suitable for sensing in harsh environment.In this review,we present the historical developments and recent advances in the fabrication technologies and sensing applications of femtosecond-laser-inscribed FBGs.Firstly,the mechanism of femtosecond-laser-induced material modification is introduced.And then,three different fabrication tech no logies,i.e.,femtosecond laser phase mask technology,femtosecond laser holographic interferometry,and femtosecond laser direct writing technology,are discussed.Finally,the advances in high-temperature sensing applications and vector bending sensing applications of various femtosecond-laser-inscribed FBGs are summarized.Such femtosecond-laser-inscribed FBGs are promising in many industrial areas,such as aerospace vehicles,nuclear plants,oil and gas explorations,and advanced robotics in harsh environments.展开更多
文摘ZrO2, CuO, Al2O3 and SiO2 mixed nanopowder was used to coat the head of sapphire single crystal fiber for improving the properties of high-temperature single crystal fiber sensor. The result indicates that the head coated with above mixed nanopowder shows better optical stability,shorter response time and higher thermal shock resistance, in comparison with the head coated with coarse-grained particles with the same chemical
文摘An extended-life and ultra-low oxygen sensor has been fabricated by using polycrystalline Caβ″/β/α-Al2O3 as a solid electrolyte. Five reference electrodes CaO+O2, Caβ″/β/α-Al2O3 (powder)+O2,Cr+Cr2O3, Nb+NbO and Mo+MoO2 were tested in order to select a better reference electrode for this sensor. The limit of determining oxygen activity and the extended-life of the sensor were also tested in this study.
基金National Natural Science Foundation of China(NSFC)(61525501)
文摘A high sensitivity D-shaped hole double-cladding fiber temperature sensor based on surface plasmon resonance(SPR)is designed and investigated by a full-vector finite element method.Within the D-shaped hole doublecladding fiber,the hollow D-section is coated with gold film and then injected in a high thermo-optic coefficient liquid to realize the high temperature sensitivity for the fiber SPR temperature sensor.The numerical simulation results show that the peaking loss of the D-shaped hole double-cladding fiber SPR is hugely influenced by the distance between the D-shaped hole and fiber core and by the thickness of the gold film,but the temperature sensitivity is almost insensitive to the above parameters.When the thermo-optic coefficient is -2.8×10^(-4)∕℃,the thickness of the gold film is 47 nm,and the distance between the D-shaped hole and fiber core is 5μm,the temperature sensitivity of the D-shaped hole fiber SPR sensor can reach to -3.635 nm∕℃.
基金Supported by Beijing Educational Committee Foundation (Km200310005022) and (00KG040)
文摘In this paper, the spectrum shift properties of the center reflection wavelength detected to be based on the FBG sensor with ambient temperature change. The basic theoretical methods and numerical simulation for the spectral properties of uniform Bragg grating is analyzed by using coupling mode theory which is optical properties of high sensitivity fiber Bragg grating on temperature sensor in accordance with experiment.
基金supported by National Natural Science Foundation of China(NSFC)(Grant Nos.U1913212,61875128,and 61635007)Department of Science and Technology of Guangdong Province(Grant Nos.2019TQ05X113,2019A1515011393,2019B1515120042,and 2019A1515111114)Shenzhen Science and Technology Program(Grant Nos.RCYX20200714114538160 and JCYJ20180507182058432).
文摘Fiber Bragg grating(FBG)is the most widely used optical fiber sensor due to its compact size,high sensitivity,and easiness for multiplexing.Conventional FBGs fabricated by using an ultraviolet(UV)laser phase-mask method require the sensitization of the optical fiber and could not be used at high temperatures.Recently,the fabrication of FBGs by using a femtosecond laser has attracted extensive interests due to its excellent flexibility in creating FBGs array or special FBGs with complex spectra.The femtosecond laser could also be used for inscribing various FBGs on almost all fiber types,even fibers without any photosensitivity.Such femtosecond-laser-induced FBGs exhibit excellent thermal stability,which is suitable for sensing in harsh environment.In this review,we present the historical developments and recent advances in the fabrication technologies and sensing applications of femtosecond-laser-inscribed FBGs.Firstly,the mechanism of femtosecond-laser-induced material modification is introduced.And then,three different fabrication tech no logies,i.e.,femtosecond laser phase mask technology,femtosecond laser holographic interferometry,and femtosecond laser direct writing technology,are discussed.Finally,the advances in high-temperature sensing applications and vector bending sensing applications of various femtosecond-laser-inscribed FBGs are summarized.Such femtosecond-laser-inscribed FBGs are promising in many industrial areas,such as aerospace vehicles,nuclear plants,oil and gas explorations,and advanced robotics in harsh environments.