We demonstrate a silicon nitride photonics-based imaging system that can perform one-dimensional interferometric imaging around the 1550-nm wavelength.The magnetograph using interferometric and computational imaging f...We demonstrate a silicon nitride photonics-based imaging system that can perform one-dimensional interferometric imaging around the 1550-nm wavelength.The magnetograph using interferometric and computational imaging for remote observations(MICRO)design uses silicon nitride on a Si platform to replace the bulky free-space optics of traditional magnetograph imaging systems with nanofabricated structures of a fraction of the size.The photonic integrated circuit(PIC)uses an array of lenslets that couple light into four input waveguides with spacing arranged along a Golomb ruler,where each aperture pair formed has a unique length.Each aperture is mixed with a 13-dBm reference laser and separated inside a 2×4 optical hybrid to generate in-phase and quadrature-phase signals to be detected in balanced detectors at the output of the PIC.We use a field programmable gate array(FPGA)board to digitize and process the measurements.The FPGAs and PIC are combined to reduce the overall size,weight,and power of the system,paving the way for a compact imaging system.We demonstrate a PIC-based imager design and experimental testbed for spectrometry applications.展开更多
We report that vector magnetograph (VMG) observations of the solar photosphere are being carride out by the Solar Flare Telescope (SOFT) at BOAO. The VMG uses a narrow band Lyot filter (FWHM=0 125A) for Stokes paramet...We report that vector magnetograph (VMG) observations of the solar photosphere are being carride out by the Solar Flare Telescope (SOFT) at BOAO. The VMG uses a narrow band Lyot filter (FWHM=0 125A) for Stokes parameter (I, Q, U, V) observations to obtain longitudinal and transverse fields. We have obtained a filter convolved line profile of Fe I 6302 5 for VMG by changing the central wavelength of the Lyot filter, which is consistent with the Sacremento Peak spectral atlas data. Using the line profile, we have determined calibration coefficients of longitudinal and transverse fields by the line slope method. Then we have compared vector fields of AR8422 observed at BOAO with those at Mitaka. The comparison shows that longitudinal fields are very similar to each other, but transverse fields are a little different. Finally, we present Hα and magnetic observations of AR8419 during its flaring activity (M3 1/1B).展开更多
磁场是太阳物理的第1观测量,当前太阳磁场观测研究正迈向大视场、高时空分辨率、高偏振测量精度以及空间观测的时代.中国首颗太阳观测卫星-先进天基太阳天文台(ASO-S)也配置了具有高时空分辨率、高磁场灵敏度的全日面矢量磁像仪(FMG)载...磁场是太阳物理的第1观测量,当前太阳磁场观测研究正迈向大视场、高时空分辨率、高偏振测量精度以及空间观测的时代.中国首颗太阳观测卫星-先进天基太阳天文台(ASO-S)也配置了具有高时空分辨率、高磁场灵敏度的全日面矢量磁像仪(FMG)载荷,针对FMG载荷的需求,讨论了大面阵、高帧频互补金属氧化物半导体(Complementary Metal Oxide Semiconductor,CMOS)图像传感器应用于太阳磁场观测的可行性.首先,基于滤光器型太阳磁像仪观测的原理,比较分析了目前CMOS图像传感器(可用的或是可选的两种快门模式)的特点,指出全局快门类型更适合FMG;其次搭建了CMOS传感器实验室测试系统,测量了CMOS图像传感器的像素增益及其分布规律;最后在怀柔太阳观测基地的全日面太阳望远镜上开展了实测验证,获得预期成果.在这些研究基础上,形成了FMG载荷探测器选型方向.展开更多
基金supported by the National Aeronautics and Space Administration(Grant No.80NSSC20K0914)the Lockheed Martin Internal Research Funds(IRAD).
文摘We demonstrate a silicon nitride photonics-based imaging system that can perform one-dimensional interferometric imaging around the 1550-nm wavelength.The magnetograph using interferometric and computational imaging for remote observations(MICRO)design uses silicon nitride on a Si platform to replace the bulky free-space optics of traditional magnetograph imaging systems with nanofabricated structures of a fraction of the size.The photonic integrated circuit(PIC)uses an array of lenslets that couple light into four input waveguides with spacing arranged along a Golomb ruler,where each aperture pair formed has a unique length.Each aperture is mixed with a 13-dBm reference laser and separated inside a 2×4 optical hybrid to generate in-phase and quadrature-phase signals to be detected in balanced detectors at the output of the PIC.We use a field programmable gate array(FPGA)board to digitize and process the measurements.The FPGAs and PIC are combined to reduce the overall size,weight,and power of the system,paving the way for a compact imaging system.We demonstrate a PIC-based imager design and experimental testbed for spectrometry applications.
文摘We report that vector magnetograph (VMG) observations of the solar photosphere are being carride out by the Solar Flare Telescope (SOFT) at BOAO. The VMG uses a narrow band Lyot filter (FWHM=0 125A) for Stokes parameter (I, Q, U, V) observations to obtain longitudinal and transverse fields. We have obtained a filter convolved line profile of Fe I 6302 5 for VMG by changing the central wavelength of the Lyot filter, which is consistent with the Sacremento Peak spectral atlas data. Using the line profile, we have determined calibration coefficients of longitudinal and transverse fields by the line slope method. Then we have compared vector fields of AR8422 observed at BOAO with those at Mitaka. The comparison shows that longitudinal fields are very similar to each other, but transverse fields are a little different. Finally, we present Hα and magnetic observations of AR8419 during its flaring activity (M3 1/1B).
文摘磁场是太阳物理的第1观测量,当前太阳磁场观测研究正迈向大视场、高时空分辨率、高偏振测量精度以及空间观测的时代.中国首颗太阳观测卫星-先进天基太阳天文台(ASO-S)也配置了具有高时空分辨率、高磁场灵敏度的全日面矢量磁像仪(FMG)载荷,针对FMG载荷的需求,讨论了大面阵、高帧频互补金属氧化物半导体(Complementary Metal Oxide Semiconductor,CMOS)图像传感器应用于太阳磁场观测的可行性.首先,基于滤光器型太阳磁像仪观测的原理,比较分析了目前CMOS图像传感器(可用的或是可选的两种快门模式)的特点,指出全局快门类型更适合FMG;其次搭建了CMOS传感器实验室测试系统,测量了CMOS图像传感器的像素增益及其分布规律;最后在怀柔太阳观测基地的全日面太阳望远镜上开展了实测验证,获得预期成果.在这些研究基础上,形成了FMG载荷探测器选型方向.