In view of the difficulties in traditional long-wave infrared imaging spectrometer which is hard to realize a high signal-to-noise ratio and miniaturization as well under the weak remote sensing signal,Offner convex g...In view of the difficulties in traditional long-wave infrared imaging spectrometer which is hard to realize a high signal-to-noise ratio and miniaturization as well under the weak remote sensing signal,Offner convex grating spectrometer and Dyson concave grating spectrometer,both having concentric structure,are designed and analyzed in the band of 8-12 μm. The diffraction angle expressions of the two spectrometers are obtained and the diffraction characteristics are acquired. Both of the spectrometers are designed in Zemax environment under different F-numbers and different grating constants with the same slit,spatial resolution,spectral resolution and detector. The results show that Dyson grating spectrometer possesses the advantages of higher throughput and smaller volume, and Offner grating spectrometer possesses the advantage of more accessible material and the absence of chromatic aberration. The differences between Dyson form and Offner form show that the former is a better choice in the long-wave infrared imaging spectrometer.展开更多
The I-V characteristic of a superconductor is generally described by power-law,in which the superconductor with a high n transfers quickly from superconducting state to the normal conducting state.With a high transpor...The I-V characteristic of a superconductor is generally described by power-law,in which the superconductor with a high n transfers quickly from superconducting state to the normal conducting state.With a high transport current,in the low n value area,flux flow voltage becomes lower than in the high n value area,so that the transient characteristics strongly affect its stability.Based on those properties,we propose a new hybrid conductor which is made of low temperature superconductor(LTS) and high temperature superconductor(HTS) with concentric configuration in which the HTS coat is located outside of the LTS core.According to their power-law models,the modified adiabatic and dynamic stability criteria are qualitatively obtained by taking account into not only their critical currents but also n values.As a result,the new hybrid conductors have potential applications with higher engineering current density and improved stability.展开更多
基金Sponsored by the National High Technology Research and Development Program of China(863 Program)(Grant No.2013AA03A116)
文摘In view of the difficulties in traditional long-wave infrared imaging spectrometer which is hard to realize a high signal-to-noise ratio and miniaturization as well under the weak remote sensing signal,Offner convex grating spectrometer and Dyson concave grating spectrometer,both having concentric structure,are designed and analyzed in the band of 8-12 μm. The diffraction angle expressions of the two spectrometers are obtained and the diffraction characteristics are acquired. Both of the spectrometers are designed in Zemax environment under different F-numbers and different grating constants with the same slit,spatial resolution,spectral resolution and detector. The results show that Dyson grating spectrometer possesses the advantages of higher throughput and smaller volume, and Offner grating spectrometer possesses the advantage of more accessible material and the absence of chromatic aberration. The differences between Dyson form and Offner form show that the former is a better choice in the long-wave infrared imaging spectrometer.
基金supported in part by the National Natural Science Foundation of China (Grant No. 51077051)
文摘The I-V characteristic of a superconductor is generally described by power-law,in which the superconductor with a high n transfers quickly from superconducting state to the normal conducting state.With a high transport current,in the low n value area,flux flow voltage becomes lower than in the high n value area,so that the transient characteristics strongly affect its stability.Based on those properties,we propose a new hybrid conductor which is made of low temperature superconductor(LTS) and high temperature superconductor(HTS) with concentric configuration in which the HTS coat is located outside of the LTS core.According to their power-law models,the modified adiabatic and dynamic stability criteria are qualitatively obtained by taking account into not only their critical currents but also n values.As a result,the new hybrid conductors have potential applications with higher engineering current density and improved stability.