双光栅光谱仪波长扫描机构精度分析  

Accuracy analysis for wavelength scanning mechanism of double grating spectrometer

作　　者：许典 林冠宇[1] 曹佃生[1] 薛庆生[1] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所,吉林长春130033 [2]中国科学院大学,北京100049

出　　处：《应用光学》2017年第1期24-30,共7页Journal of Applied Optics

基　　金：国家自然科学基金重大科研仪器设备研制专项(41527806)

摘　　要：光栅光谱仪作为研究太阳辐射的重要设备之一,其波长扫描机构的精度很大程度上决定了最终测量结果的准确性。从光机系统的光栅参量误差和机械结构误差两方面入手,对丝杠摆杆波长扫描机构展开综合精度分析,依据凹面光栅色散原理,推导出波长λ与摆杆末端沿丝杠方向位移x,摆杆长度l,光栅常数g和入射光线与出射光线夹角半值δ之间的关系。再对等式求导,依据误差叠加原理,计算出在红外工作波段650nm^2 400nm范围内,其波长定标误差应不超过±1.227nm。在实验样机上进行验证,以汞灯为光源拟合出误差与波长的关系曲线,并以氦氖激光器为光源加以验证。实验结果证明了理论计算的正确性,该分析方法为双光栅光谱仪零部件精度指标的确定提供了依据。Grating spectrometer is one of the most important instruments in studying solar radi-ation, and accuracy of its wavelength scanning mechanism determines final measurement result. Taking errors from both grating parameters and machining dimensions into eonsidera-tion, this paper analyzes comprehensive accuracy of wavelength scanning mechanism which is made up of screw and swing. Based on dispersive principle of concave grating, relationships be-tween wavelength λ and displacement of end swing along direction of screw x, swing length l, grating constant g and half angle between incident light and diffraction light δ are derived. Then derivatives of equation are obtain, and wavelength errors are calculated between 650 nm and 2 400 nm and should be no more than ±1. 227 nm according to principle of errors stack. Then results are tested on prototype. Fitted curve of wavelength and error can be obtained when taking mercury lamp as light source, and can be checkeded when taking helium neon la-ser as fight source. Results prove correctness of theorectical calculation method, and provide theory evidence in choosing components.

关 键 词：精度分析 光栅光谱仪 波长定标 正弦机构 

分 类 号：TN203[电子电信—物理电子学] TH841[机械工程—仪器科学与技术]