面阵傅里叶变换太阳光谱仪高速采集系统设计与实现

同时或准同时多谱线太阳成像观测可以获得太阳大气三维磁场和热力学参数，是未来太阳观测焦面终端设备的重点发展方向。傅里叶光谱仪具有宽波段、高灵敏度、高光谱分辨率的优势，但因受限于高帧频、大面阵探测器制约，尚未用于太阳光谱成像常规观测。随着CMOS图像传感器技术迅猛发展，在可见光和近红外波段，探测器面阵大小和帧频相比传统CCD探测器有了质的提升，使得面阵傅里叶太阳光谱仪研制成为可能。通过引入高帧频面阵CMOS图像传感器，针对面阵傅里叶变换太阳光谱仪科学需求，设计了一套高速数据采集软硬件系统，实现了面阵傅里叶太阳光谱仪10 kHz高速触发，万帧/秒快速采集，0.5 GB·s-1大数据量连续、实时存储等功能。在此基础上，依托国家天文台怀柔太阳观测基地现有的IFS-125HR傅里叶变换光谱仪, 搭建可见光实验系统，以可见光色球谱线（Hα 656.3 nm）及其附近光球谱线为目标波长，开展面源太阳光谱探测。分别以实验室钨灯和太阳为光源，进行等光程差间隔采样，成功获得了面阵干涉图，首次反演得到面源窄带连续谱以及656.3 nm附近太阳色球和光球线。采用交叉定标方式，将得到的太阳光谱与美国国立太阳天文台NSO傅里叶变换光谱仪获得的标准光谱在同等分辨率下进行比较，结果基本一致，验证了新研制的面阵傅里叶太阳光谱仪高速数据采集系统性能及面阵傅里叶变换太阳光谱仪在太阳观测中的可行性。该研究为后续可见光宽波段面阵傅里叶太阳光谱仪的研制奠定了技术基础，同时为“用于太阳磁场精确测量的中红外观测系统”（AIMS）后续从线源扩展到面源观测积累了宝贵经验。

Design and Realization of High-Speed Acquisition System for Two Dimensional Fourier Transform Solar Spectrometer

Simultaneous or quasi-simultaneous multi-spectral solar imaging can be used to obtain the solar atmosphere’s three-dimensional magnetic field and thermodynamic parameters, which is a key development direction of the focal plane terminal equipment for solar observations in the future. The Fourier transform spectrometer (FTS) has a wide bandwidth, high sensitivity and a high spectral resolution, but it is restricted by high frame rate and large area array detector. It has not been used for routine solar spectrum imaging yet. However, with the rapid development of CMOS image sensor technology, in the visible and near-infrared bands, the size and frame rate of the detector array have been qualitatively improved compared to traditional CCD detectors, making it possible to develop an area array, Fourier, solar spectrometer. Here in this paper, we introduce an area array, and high frame rate CMOS image sensor and design a set of high-speed data acquisition software and hardware systems for the scientific needs of area array Fourier transform solar spectrometers. It realizes the 10 kHz high-speed triggering, fast acquisition of 10 000 frames per second, 0.5 GB·s-1 large data volume continuous, real-time storage and other functions. Combining with the above system and the existing point source FTS at the Huairou Solar Observing Station and targeting the visible light chromosphere line (Hα 656.3 nm) and its nearby photosphere line, we set up a visible light experimental system and carried out surface source solar spectrum detection. We used the laboratory tungsten lamp and the sun as the light source, performed equal optical path difference interval sampling, and successfully obtained the area array interferogram. We obtained the narrow-band continuum spectrum and the solar chromosphere and photosphere line near 656.3 nm. Using the cross-calibration method, we compared our solar spectrum at the same resolution with the standard spectrum obtained by the National Solar Astronomical Observatory’s NSO Fourier Spectrometer, and the results are the same, verifying the performance of the data acquisition system for the FTS of the plane array and the feasibility of area array Fourier Transform Solar Spectrometer in solar observation. This research lays a technical foundation for the wide-band solar FTS of the plane array in the visible region and at the same time, accumulates valuable experience for the subsequent extension of “The Infrared System for the Accurate Measurement of Solar Magnetic Field” (AIMS) from the line source to the plane source.