宽谱段空间外差干涉光谱仪

研究了基于中阶梯光栅多级衍射特性实现谱段展宽的宽谱段空间外差干涉光谱仪的基础理论和系统设计方法。阐述了宽谱段空间外差干涉光谱仪的特点,分析了仪器性能指标(光谱分辨率、光谱范围、视场、信噪比、衍射级次等)与初始光学和电子学参数(光栅、视场棱镜、成像系统、探测器等)之间的理论关系。然后,设计并搭建了宽谱段空间外差干涉光谱仪实验平台,该系统的理论光谱分辨率为0.173cm-1@16 950cm-1,光谱区为500~700nm。最后,给出了激光(543.5nm、632.8nm)、Na灯(589nm、589.6nm)、Hg灯(576.96nm、579.07nm)光源的宽谱段实验结果,其复原光谱的平均波数采样间隔为0.17cm-1;光谱复原过程中采用三角切趾函数,平均光谱分辨率为0.39cm-1。实验结果与理论设计符合良好,且复原谱各级次之间的对应关系与光栅方程确定的理论关系完全符合。

Broad-band spatial heterodyne interferometric spectrometer

The basic theory and design method of a broad-band spatial heterodyne interferometric spectrometer was researched based on the multi-order diffraction of echelle grating. The characteristics of the heterodyne interferometric spectrometer was described and the relationships between the instrument performance parameters (such as spectral resolution, spectral range, signal-to-noise ratio, field of view, and diffraction order) and the initial optical and electronic parameters (such as echelle grating, field prism, imaging system and detector) were discussed. Then, an experimental platform for the broad-band spatial heterodyne spectrometer was settled to demonstrate the above discussions. The designed spectral resolution is 0.173 cm^-1@16 950 cm^-1, and the spectral range is 500 nm to 700 nm. The broad-band results were given with a laser source (543.5 nm, 632.8 nm), a sodium lamb (589 nm, 589.6 nm) and a mercury lamb (576.96 nm、579.07 nm). It shows that the average wavenumber sampling interval of recovered spectra is 0.17 cm^-1.When the triangle apodization is used in the process of spectral recovery, the measured spectral resolution is 0.39 cm^-1.The obtained results conform to theoretical results and the relationship among orders of recovered spectrum accords with the theory results decided by grating function.