A design for low power consumption inspection instrument, in which the ATMega32L is used as the control core, is presented. The reader with wireless identification based on RF technology is researched and the low-cost...A design for low power consumption inspection instrument, in which the ATMega32L is used as the control core, is presented. The reader with wireless identification based on RF technology is researched and the low-cost power is studied particularly. This instrument can be used in industry fields to measure temperature, humidity, gas concentration and other specifications, so it has wide applications and is worth to be extended.展开更多
The development of two simple methods for wavelength-optical intensity modulation techniques for fiber Bragg grating （FBG） sensors is presented. The performance is evaluated by measuring the strain and temperature. ...The development of two simple methods for wavelength-optical intensity modulation techniques for fiber Bragg grating （FBG） sensors is presented. The performance is evaluated by measuring the strain and temperature. The first method consists of a narrow band source, an optical circulator, an FBG; and a power meter. The source and Bragg reflected signal from the FBG need to be matched to get linear results with good power levels. The source spectral power levels are very critical in this study. The power reflected from a matched reference FBG is fed into the measuring FBG in the second method. Since the FBGs are matched, the entire power is reflected back initially. During the measurement, the change in the measurand causes the reflected power from the sensing FBG to vary. A costly high resolution spectrum analyzer is required only during the characterization of the FBG and source. The performances of two interrogators are compared by measuring the strain and temperature. In the second method, the strain measurements can be made insensitive to the temperature variation by selecting a source with a flat spectrum at the measurement range. Highlights of these methods are the portability, cost effectiveness and better resolution.展开更多
This article reviews my new optical fiber sensing （OFS） research activities in China for the last ten years at Chongqing University and University of Electronic Science and Technology of China, since I returned from...This article reviews my new optical fiber sensing （OFS） research activities in China for the last ten years at Chongqing University and University of Electronic Science and Technology of China, since I returned from UK in 1999. The research progress in long period fiber gratings （LPFGs）, distributed fiber sensing systems and microfiber sensors is introduced. For LPFGs, the processing method with high-frequency CO2 laser pulses types of LPFGs fabricated and the related applications for both optical sensing and optical communication are described. For distributed fiber sensing systems, the fiber-optic polarization optical time domain reflectometer （POTDR）, fiber-optic phase-sensitive optical time domain reflectometer （φ-OTDR） and Brillouin optical time-domain analyzer （BOTDA） are developed, respectively. For microfiber sensors, we mainly focus on the knot resonator and its application for sensing of the refractive index and acceleration, etc.展开更多
基金National Natural Science Foundation of Tianjin(08JCYBJC14700)
文摘A design for low power consumption inspection instrument, in which the ATMega32L is used as the control core, is presented. The reader with wireless identification based on RF technology is researched and the low-cost power is studied particularly. This instrument can be used in industry fields to measure temperature, humidity, gas concentration and other specifications, so it has wide applications and is worth to be extended.
文摘The development of two simple methods for wavelength-optical intensity modulation techniques for fiber Bragg grating （FBG） sensors is presented. The performance is evaluated by measuring the strain and temperature. The first method consists of a narrow band source, an optical circulator, an FBG; and a power meter. The source and Bragg reflected signal from the FBG need to be matched to get linear results with good power levels. The source spectral power levels are very critical in this study. The power reflected from a matched reference FBG is fed into the measuring FBG in the second method. Since the FBGs are matched, the entire power is reflected back initially. During the measurement, the change in the measurand causes the reflected power from the sensing FBG to vary. A costly high resolution spectrum analyzer is required only during the characterization of the FBG and source. The performances of two interrogators are compared by measuring the strain and temperature. In the second method, the strain measurements can be made insensitive to the temperature variation by selecting a source with a flat spectrum at the measurement range. Highlights of these methods are the portability, cost effectiveness and better resolution.
文摘This article reviews my new optical fiber sensing （OFS） research activities in China for the last ten years at Chongqing University and University of Electronic Science and Technology of China, since I returned from UK in 1999. The research progress in long period fiber gratings （LPFGs）, distributed fiber sensing systems and microfiber sensors is introduced. For LPFGs, the processing method with high-frequency CO2 laser pulses types of LPFGs fabricated and the related applications for both optical sensing and optical communication are described. For distributed fiber sensing systems, the fiber-optic polarization optical time domain reflectometer （POTDR）, fiber-optic phase-sensitive optical time domain reflectometer （φ-OTDR） and Brillouin optical time-domain analyzer （BOTDA） are developed, respectively. For microfiber sensors, we mainly focus on the knot resonator and its application for sensing of the refractive index and acceleration, etc.
