基于虚像相位阵列光谱仪的宽带高分辨率CO_(2)吸收光谱测量技术研究  

High-Resolution and Broadband Spectral Measurement of CO_(2) Based on Virtually Imaged Phased Array Spectrometer

作　　者：周昊 赵卫雄[1,2] 吕丙选[1,2] 崔卫华 方波 杨娜娜 张为俊[1,2] Zhou Hao;Zhao Weixiong;Li Bingxuan;Cui Weihua;Fang Bo;Yang Nana;Zhang Weijun(Anhui Institute of Optics and Fine Mechanics,Hefei Institutes of Physical Sciences,Chinese Academy of Sciences,Hefei 230031,Anhui,China;University of Science and Technology of China,Hefei 230026,Anhui,China)

机构地区：[1]中国科学院合肥物质科学研究院安徽光学精密机械研究所,安徽合肥230031 [2]中国科学技术大学,安徽合肥230036

出　　处：《光学学报》2023年第18期178-186,共9页Acta Optica Sinica

基　　金：国家自然科学基金(42022051,U21A2028);中国科学院青年创新促进会(Y202089);中国科学院合肥物质科学研究院院长基金(YZJJ202101)。

摘　　要：为了使光谱仪能同时兼顾宽吸收光谱范围和高光谱分辨率两种特性,搭建了一台近红外虚像相位阵列光谱仪,单帧谱宽约为25nm(140cm^(-1)),光谱分辨率为4.5pm(0.024cm^(-1)),结合改进的旋转光栅结构,实现了1.26~1.50μm的宽光谱检测。使用超连续光源及光学吸收多通池,在1.43~1.45μm处,以CO_(2)为例开展了宽带高分辨光谱测量技术研究,使用图像增强算法提高了弱吸收的光谱提取精度,考虑光谱仪的仪器展宽进而提升了气体参数反演准确度。实测光谱与理论光谱的对比结果验证了系统测量的准确性与可靠性。Objective Broadband and high-resolution spectroscopy plays a significant role in many research fields such as atmospheric trace gas detection,industrial monitoring,precision measurement,and basic physics and chemistry.Large spectral bandwidth allows for the simultaneous detection of multiple species,which enables a single instrument to have many functions.However,detection techniques that can provide a pm-level spectral resolution over a wide bandwidth still need to be further studied.The virtually imaged phased array(VIPA)is a plane-parallel etalon,where the input beam is injected at an angle through an entrance window on the front face.The multiple reflections occur within the VIPA etalon.The emerging light interferes to make different frequencies exit at different angles.VIPA spectrometer is an orthogonal dispersion system composed of VIPA and grating and can achieve spectral coverage of tens of nm in a single frame and spectral resolution of pm.In the past years,the VIPA spectrometer has been widely applied in high-precision broadband spectral measurement.However,practical applications of VIPA spectrometer face the following problems.First,some algorithms that employ gas absorption to calibrate the VIPA spectrometer ignore the instrument lineshape function(ILS),and second,these algorithms are difficult to calibrate when weakly absorbed.Additionally,the adjustment structure of the VIPA spectrometer can still be improved.Our paper reports an improved near-infrared spectrometer based on the VIPA and presents the experimental details and performance evaluation.The broadband and high-resolution measurement technology of CO_(2)in 1.43-1.45μm is carried out by combining the supercontinuum source and multi-pass cell.The results verify the reliability of the system and the accuracy of the improved data processing algorithm.Methods The experimental system mainly consists of a supercontinuum laser,a Chernin muti-pass cell,and a VIPA spectrometer.The broadband light is collimated by the aspheric collimator.Then the emer

关 键 词：虚像相位阵列光谱仪 宽带吸收光谱 高分辨率 CO_(2)探测 

分 类 号：O439[机械工程—光学工程]