Employing a fiber Fabry-Perot (FFP) interferometer has been considered as a triangle notch filter to demodulate the wavelength of fiber Bragg grating (FBG) sensor.The single parameter of strain has been demodulated,an...Employing a fiber Fabry-Perot (FFP) interferometer has been considered as a triangle notch filter to demodulate the wavelength of fiber Bragg grating (FBG) sensor.The single parameter of strain has been demodulated,and the cross-sensitivity influence of temperature has been eliminated.The principle of this method is simple and easy to be implemented,and has been used to design a 30 t fiber grating weightbridge successfully.The maximal temperature drift error of the weightbridge is 4 με,which means that the full scale error is 8‰. The result reveals that the accuracy is high enough to be used in measurement.展开更多
The retardation of wave plate has the sensitivity to the incident angle.We design a new kind of tunable Lyot filter based on the sensitivity.The method of tuning is rotating the wave plate by the axial direction paral...The retardation of wave plate has the sensitivity to the incident angle.We design a new kind of tunable Lyot filter based on the sensitivity.The method of tuning is rotating the wave plate by the axial direction parallel to the optical axis.It is proved that this kind of tunable Lyot filter has the properties of favorable tenability,wide tunable range.展开更多
Conventional angle-tuned thin-film filters have serious angle sensitivity for their low spacer effective refractive index, and it is difficult to fabricate their angle control system. In this paper, we propose and fab...Conventional angle-tuned thin-film filters have serious angle sensitivity for their low spacer effective refractive index, and it is difficult to fabricate their angle control system. In this paper, we propose and fabricate a novel 100 GHz angletuned thin-film filter stack with low angle sensitivity, which uses the high refractive index material TiO2 as the spacer, and its incident angle can be expanded to 25°. Compared with the traditional Ta2O5-SiO2 thin-film filter stack, the novel stack has fewer layers. Using the polarization beam splitters and the half wave plates, the polarization sensitivity of the angle-tuned filter can also be suppressed. Simulation results and the experiments show that the thin-film filter with low angle sensitivity has an effective tuning range of 33 nm, which can cover the whole C-band, and its angle control system is easy to be fabricated.展开更多
文摘Employing a fiber Fabry-Perot (FFP) interferometer has been considered as a triangle notch filter to demodulate the wavelength of fiber Bragg grating (FBG) sensor.The single parameter of strain has been demodulated,and the cross-sensitivity influence of temperature has been eliminated.The principle of this method is simple and easy to be implemented,and has been used to design a 30 t fiber grating weightbridge successfully.The maximal temperature drift error of the weightbridge is 4 με,which means that the full scale error is 8‰. The result reveals that the accuracy is high enough to be used in measurement.
文摘The retardation of wave plate has the sensitivity to the incident angle.We design a new kind of tunable Lyot filter based on the sensitivity.The method of tuning is rotating the wave plate by the axial direction parallel to the optical axis.It is proved that this kind of tunable Lyot filter has the properties of favorable tenability,wide tunable range.
基金supported by the Scientific Research Project of Hubei Education Department(No.B2014246)the National Natural Science Foundation of China(No.61205062)+1 种基金the Natural Science Foundation of Hubei Province in China(No.2012FFB02701)the Project of Hubei Province Universities Outstanding Youth Scientific Innovation Team(No.T201431)
文摘Conventional angle-tuned thin-film filters have serious angle sensitivity for their low spacer effective refractive index, and it is difficult to fabricate their angle control system. In this paper, we propose and fabricate a novel 100 GHz angletuned thin-film filter stack with low angle sensitivity, which uses the high refractive index material TiO2 as the spacer, and its incident angle can be expanded to 25°. Compared with the traditional Ta2O5-SiO2 thin-film filter stack, the novel stack has fewer layers. Using the polarization beam splitters and the half wave plates, the polarization sensitivity of the angle-tuned filter can also be suppressed. Simulation results and the experiments show that the thin-film filter with low angle sensitivity has an effective tuning range of 33 nm, which can cover the whole C-band, and its angle control system is easy to be fabricated.
