光谱学与光谱分析, 2015, 35 (4): 1116, 网络出版: 2015-04-20
空间外差光谱仪中窄带滤光片的光谱特性研究
Study on the Spectral Characteristics of the Narrow-Band Filter in SHS
窄带滤光片 空间外差光谱仪 基频 光谱混叠 Narrow-band filter Spatial heterodyne spectroscopy(SHS) Basic frequency Spectral confusion
摘要
高光谱空间外差干涉光谱仪的光谱响应由窄带滤光片的光谱特性决定,由于窄带滤光片的制备水平与理论值存在差距,使得发生光谱展宽或波长漂移等现象,在空间外差光谱仪中形成高频和低频光谱混叠从而导致复原光谱失真.在分析滤光片对仪器光谱响应性能影响的基础上,通过在空间外差光谱仪核心干涉组件光栅的胶合过程中,根据窄带滤光片实测波长透过率曲线,利用可调谐激光器动态监测调整光谱仪基频波长的方法改善对其造成的光谱混叠.结果表明,通过实测滤光片特性调整光栅偏转角度来改变基频波长,可最大程度地有效利用仪器所能覆盖的光谱范围,根据干涉图的复原光谱信号可知试验装置的有效光谱范围从758~770.9 nm增加至756~770.9 nm.
Abstract
The spectral response of spatial heterodyne spectroscopy (SHS) is determined by the spectrum property of narrow-band filter.As discussed in previous studies,the symmetric heterodyned interferogram of high frequency waves modulated by SHS and lack of sample lead to spectral confusion,which is associated with the true and ghost spectra.Because of the deviation from theoretical index of narrow-band filter in the process of coating,the boarded spectral response and middle wave shift are presented,and conditions in the theoretical Littrow wavelength made the effective wavelength range of SHS reduced.According to the measured curve of filter,a new wavenumber of zero spatial frequency can be reset by tunable laser,and it is easy for SHS to improve the spectral aliasing distortion.The results show that it is utilized to the maximum extent of the effective bandwidth by adjusting the grating angle of rotation to change the Littrow wavelength of the basic frequency,and the spectral region increased to 14.9 nm from original 12.9 nm.
罗海燕, 施海亮, 李志伟, 李双, 熊伟, 洪津. 空间外差光谱仪中窄带滤光片的光谱特性研究[J]. 光谱学与光谱分析, 2015, 35(4): 1116. LUO Hai-yan, SHI Hai-liang, LI Zhi-wei, LI Shuang, XIONG Wei, HONG Jin. Study on the Spectral Characteristics of the Narrow-Band Filter in SHS[J]. Spectroscopy and Spectral Analysis, 2015, 35(4): 1116.