In this paper, the reflective spectra of a refraction index sensor were analyzed based on fiber grating F-P cavity. The sensor was constituted by two identical fiber gratings. Compared with the refraction index sensor...In this paper, the reflective spectra of a refraction index sensor were analyzed based on fiber grating F-P cavity. The sensor was constituted by two identical fiber gratings. Compared with the refraction index sensor using one fiber grating, the fiber grating F-P cavity sensor has narrower resonant peak and it can be used for more accurate measurement. The resonant peaks in the reflective spectra of the sensor are changed with small changes of the refraction index of the measured chemical liquids or cell samples. So it has potential applications in biology and chemistry.展开更多
An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the ca...An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the cavity length of EF- PI fiber optical sensor. There are many ways to achieve the demodulation of the cavity length. For shortcomings of the big intensity demodulation error and complex structure of phase demodulation, this paper proposes that BP neural net-work is used to locate the special peak points in normalized interference spectrum and combining the advantages of the unimodal and bimodal measurement achieves the demodulation of the cavity length. Through online simulation and actual measurement, the results show that the peak positioning technology based on BP neural network can not only achieve high-precision demodulation of the cavity length, but also achieve an absolute measurement of cavity length in large dynamic range.展开更多
We demonstrate a fiber Fabry-Pérot cavity in the ultraviolet range, which covers the florescence wavelength for the <sup>2</sup>P to <sup>2</sup>S transition of Yb and is designed in the b...We demonstrate a fiber Fabry-Pérot cavity in the ultraviolet range, which covers the florescence wavelength for the <sup>2</sup>P to <sup>2</sup>S transition of Yb and is designed in the bad cavity limit for florescence collection. Benefiting from both the small cavity mode volume and the large atom dipole, a cavity with moderate finesse and high transmission still supports a good cooperativity, which is made and tested in experiment. Based on the measured experimental parameters, simulation performed on the cavity and ion shows a Purcell factor better than 2.5 and a single-mode fiber collection efficiency over 10%. This technology can support ultra-bright single photon sources based on trapped ions and can provide the possibility to link remote atoms as a quantum network.展开更多
Acoustic/ultrasonic sensors are devices that can convert mechanical energy into electrical signals.The Fabry–Perot cavity is processed on the end face of the double-clad fiber by a two-photon three-dimensional lithog...Acoustic/ultrasonic sensors are devices that can convert mechanical energy into electrical signals.The Fabry–Perot cavity is processed on the end face of the double-clad fiber by a two-photon three-dimensional lithography machine.In this study,the outer diameter of the core cladding was 250μm,the diameter of the core was 9μm,and the microcavity sensing unit was only 30μm.It could measure ultrasonic signals with high precision.The characteristics of the proposed ultrasonic sensor were investigated,and its feasibility was proven through experiments.Its design has a small size and can replace a larger ultrasonic detector device for photoacoustic signal detection.The sensor is applicable to the field of biomedical information technology,including medical diagnosis,photoacoustic endoscopy,and photoacoustic imaging.展开更多
We demonstrate a smart optical fiber sensor unit to realize a multi-parameter sensing, including temperature, curvature and strain or displacement. The sensor unit is composed of a Bragg grating in graded-index multim...We demonstrate a smart optical fiber sensor unit to realize a multi-parameter sensing, including temperature, curvature and strain or displacement. The sensor unit is composed of a Bragg grating in graded-index multimode fiber and a Fizeau cavity.展开更多
This paper presents a novel miniaturized fiber-optic Fabry-Peort interferometer （FPI） for highly sensitive refractive index measurement. This device was tested for the refractive indices of various liquids including...This paper presents a novel miniaturized fiber-optic Fabry-Peort interferometer （FPI） for highly sensitive refractive index measurement. This device was tested for the refractive indices of various liquids including acetone and ethanol at room temperature. The sensitivity for measurement of refractive index change of ethanol is 1138 nm/RIU at the wavelength of 1550 nm. In addition, the sensor fabrication is simple including only cleaving, splicing, and etching. The signal is stable with high visibility. Therefore, it provides a valuable tool in biological and chemical applications.展开更多
An optical micro electron mechanical system （MEMS） pressure sensor with a mesa membrane is presented. The operating principle of the MEMS pressure sensor is expatiated by the Fabry-Perot （F-P） interference and the...An optical micro electron mechanical system （MEMS） pressure sensor with a mesa membrane is presented. The operating principle of the MEMS pressure sensor is expatiated by the Fabry-Perot （F-P） interference and the relation between deflection and pressure is analyzed. Both the mechanical model of the mesa structure diaphragm and the signal averaging effect is validated by simulation, which declares that the mesa structure diaphragm is superior to the planar one on the parallelism and can reduce the signal averaging effect. Experimental results demonstrate that the mesa structure sensor has a reasonable linearity and sensitivity.展开更多
A novel fiber magnetic sensor based on the fiber Bragg grating Fabry-Perot （FBG-FP） cavity ring-down technique with pulse laser injection is proposed and demonstrated theoretically. A general expression of the inten...A novel fiber magnetic sensor based on the fiber Bragg grating Fabry-Perot （FBG-FP） cavity ring-down technique with pulse laser injection is proposed and demonstrated theoretically. A general expression of the intensity of the output electric field is derived, and the effect of the external magnetic field on the ring-down time is discussed. The results show that the output light intensity and the ring-down time of the FBG-FP cavity are in the inverse proportion to the magnitude of the external magnetic field. Our results demonstrate the new concept of the fiber magnetic sensor with the FBG-FP cavity ring-down spectroscopy and the technical feasibility.展开更多
基金National Natural Science Foundation of China(10774058)
文摘In this paper, the reflective spectra of a refraction index sensor were analyzed based on fiber grating F-P cavity. The sensor was constituted by two identical fiber gratings. Compared with the refraction index sensor using one fiber grating, the fiber grating F-P cavity sensor has narrower resonant peak and it can be used for more accurate measurement. The resonant peaks in the reflective spectra of the sensor are changed with small changes of the refraction index of the measured chemical liquids or cell samples. So it has potential applications in biology and chemistry.
文摘An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the cavity length of EF- PI fiber optical sensor. There are many ways to achieve the demodulation of the cavity length. For shortcomings of the big intensity demodulation error and complex structure of phase demodulation, this paper proposes that BP neural net-work is used to locate the special peak points in normalized interference spectrum and combining the advantages of the unimodal and bimodal measurement achieves the demodulation of the cavity length. Through online simulation and actual measurement, the results show that the peak positioning technology based on BP neural network can not only achieve high-precision demodulation of the cavity length, but also achieve an absolute measurement of cavity length in large dynamic range.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11274289,11325419,11474267,11404319,61327901,61225025 and 1147426the Fundamental Research Funds for the Central Universities under Grant Nos WK2470000018 and WK2030020019+2 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences under Grant No XDB01030300the National Youth Top Talent Support Program of National High-level Personnel of Special Support Program under Grant No BB2470000005the Anhui Provincial Natural Science Foundation under Grant No 1608085QA22
文摘We demonstrate a fiber Fabry-Pérot cavity in the ultraviolet range, which covers the florescence wavelength for the <sup>2</sup>P to <sup>2</sup>S transition of Yb and is designed in the bad cavity limit for florescence collection. Benefiting from both the small cavity mode volume and the large atom dipole, a cavity with moderate finesse and high transmission still supports a good cooperativity, which is made and tested in experiment. Based on the measured experimental parameters, simulation performed on the cavity and ion shows a Purcell factor better than 2.5 and a single-mode fiber collection efficiency over 10%. This technology can support ultra-bright single photon sources based on trapped ions and can provide the possibility to link remote atoms as a quantum network.
基金This work was supported in part by the Natural Science Foundation of Guangdong Province,No.2020A1515010958Key Project of Shenzhen Science and Technology Plan,No.JCYJ20200109113808048.
文摘Acoustic/ultrasonic sensors are devices that can convert mechanical energy into electrical signals.The Fabry–Perot cavity is processed on the end face of the double-clad fiber by a two-photon three-dimensional lithography machine.In this study,the outer diameter of the core cladding was 250μm,the diameter of the core was 9μm,and the microcavity sensing unit was only 30μm.It could measure ultrasonic signals with high precision.The characteristics of the proposed ultrasonic sensor were investigated,and its feasibility was proven through experiments.Its design has a small size and can replace a larger ultrasonic detector device for photoacoustic signal detection.The sensor is applicable to the field of biomedical information technology,including medical diagnosis,photoacoustic endoscopy,and photoacoustic imaging.
文摘We demonstrate a smart optical fiber sensor unit to realize a multi-parameter sensing, including temperature, curvature and strain or displacement. The sensor unit is composed of a Bragg grating in graded-index multimode fiber and a Fizeau cavity.
基金supported by the Key Project of Natural Science Foundation of China under Grant No. 60537040the Natural Science Foundation Project of CQ CSTC under Grant No. 2007BB3125
文摘This paper presents a novel miniaturized fiber-optic Fabry-Peort interferometer （FPI） for highly sensitive refractive index measurement. This device was tested for the refractive indices of various liquids including acetone and ethanol at room temperature. The sensitivity for measurement of refractive index change of ethanol is 1138 nm/RIU at the wavelength of 1550 nm. In addition, the sensor fabrication is simple including only cleaving, splicing, and etching. The signal is stable with high visibility. Therefore, it provides a valuable tool in biological and chemical applications.
文摘An optical micro electron mechanical system （MEMS） pressure sensor with a mesa membrane is presented. The operating principle of the MEMS pressure sensor is expatiated by the Fabry-Perot （F-P） interference and the relation between deflection and pressure is analyzed. Both the mechanical model of the mesa structure diaphragm and the signal averaging effect is validated by simulation, which declares that the mesa structure diaphragm is superior to the planar one on the parallelism and can reduce the signal averaging effect. Experimental results demonstrate that the mesa structure sensor has a reasonable linearity and sensitivity.
文摘A novel fiber magnetic sensor based on the fiber Bragg grating Fabry-Perot （FBG-FP） cavity ring-down technique with pulse laser injection is proposed and demonstrated theoretically. A general expression of the intensity of the output electric field is derived, and the effect of the external magnetic field on the ring-down time is discussed. The results show that the output light intensity and the ring-down time of the FBG-FP cavity are in the inverse proportion to the magnitude of the external magnetic field. Our results demonstrate the new concept of the fiber magnetic sensor with the FBG-FP cavity ring-down spectroscopy and the technical feasibility.
