Chinese Journal of Lasers, Vol. 46, Issue 9, 0911004 (2019)
Wavelength Nonlinearity of Multi-Channel Solar Spectrometer with Common Grating Rotating Axis
Li Zhanfeng1, Huang Yu1, Wang Shurong1,*, Yu Miao2, Lin Guanyu1, Zhang Zihui1, and Cao Diansheng1
- 1 State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, Jilin 130033, China
- 2 Load and Ground Application Technology Laboratory, Shanghai Institute of Satellite Engineering,Shanghai 200240, China
To improve the wavelength calibration accuracy of multi-channel grating scanning spectrometers, the principle of linear wavelength scanning of traditional single-channel grating spectrometers is first introduced. Then, the theoretical nonlinear relationship between the spectrometer's output wavelength and the moving distance of the lead screw is derived based on the common grating axis error. Given the nonlinear relationship, wavelength calibration of a prototype of Fengyun-3 solar irradiance spectrometer is performed. The results demonstrate that the calibration accuracy of the traditional calibration is 0.08 nm,and the calibration accuracy is increased to 0.03 nm by using the wavelength nonlinear formula. This result satisfies the requirements of the instrument's specifications. Thus, the wavelength nonlinear relationship of a multi-channel grating scanning spectrometer is verified.