A novel long-period fiber grating （LPFG） film methane sensor is designed and applied successfully. The sensor is constructed by depositing a thin styrene-acrylonitrile （SAN） film containing the new compound crypto...A novel long-period fiber grating （LPFG） film methane sensor is designed and applied successfully. The sensor is constructed by depositing a thin styrene-acrylonitrile （SAN） film containing the new compound cryptophane-E-（OEt）6 onto the cladding surface of the LPFG. This film is sensitive to methane gas. Methane causes a change in the refractive index of the sensing film, which can be measured by shifting the resonance wavelength. Experimental results show that the resonant wavelength shifts to the longer wavelength, with increasing methane concentration at a range of 0.0%–3.5% （v/v）. A linear relationship is obtained within the test range. Detection limit is estimated at 0.2%, and response time is 60 s. No significant interference is detected from dry air, O2 , CO, CO2 , and H2 . This novel methane sensing material has great application potential due to its advantages.展开更多
We report periodical rocking long period gratings(PR-LPGs) in PANDA fibers fabricated with CO_2 laser. The PR-LPGs achieve very high coupling efficiency of 19 dB with 12 periods and a 3.5° twist angle in just one...We report periodical rocking long period gratings(PR-LPGs) in PANDA fibers fabricated with CO_2 laser. The PR-LPGs achieve very high coupling efficiency of 19 dB with 12 periods and a 3.5° twist angle in just one scanning cycle, which is much more effective than the conventional CO_2 laser fabrication technique. This type of LPGs exhibits polarization-selective resonance dips which demonstrate different sensitivities to environmental parameters. The high temperature and external refractive index sensitivities are measured simultaneously, so it can be used as a wavelength-selective polarization filter and sensor.展开更多
基金supported by the National Natural Science Foundation of China (No. 60871039)the Natural Science Foundation Project of Chongqing (No. 2010BB4246)+1 种基金the Science and Technology Development Project of Chongqing (No. CSTC2012gg-yyis 9007)the Sharing Fund of Chongqing University sLarge-Scale Equipment
文摘A novel long-period fiber grating （LPFG） film methane sensor is designed and applied successfully. The sensor is constructed by depositing a thin styrene-acrylonitrile （SAN） film containing the new compound cryptophane-E-（OEt）6 onto the cladding surface of the LPFG. This film is sensitive to methane gas. Methane causes a change in the refractive index of the sensing film, which can be measured by shifting the resonance wavelength. Experimental results show that the resonant wavelength shifts to the longer wavelength, with increasing methane concentration at a range of 0.0%–3.5% （v/v）. A linear relationship is obtained within the test range. Detection limit is estimated at 0.2%, and response time is 60 s. No significant interference is detected from dry air, O2 , CO, CO2 , and H2 . This novel methane sensing material has great application potential due to its advantages.
基金supported by the National Natural Science Foundation of China(No.61605168)the Natural Science Foundation of Hebei Province(No.F2016203392)+2 种基金the College and University Natural Science Foundation of Hebei Province(No.QN2016078)the Science and Technology Project of Qinhuangdao City(No.201601B050)the Intramural Doctoral Foundation of Yanshan Universtiy(No.B1011)
文摘We report periodical rocking long period gratings(PR-LPGs) in PANDA fibers fabricated with CO_2 laser. The PR-LPGs achieve very high coupling efficiency of 19 dB with 12 periods and a 3.5° twist angle in just one scanning cycle, which is much more effective than the conventional CO_2 laser fabrication technique. This type of LPGs exhibits polarization-selective resonance dips which demonstrate different sensitivities to environmental parameters. The high temperature and external refractive index sensitivities are measured simultaneously, so it can be used as a wavelength-selective polarization filter and sensor.
