基于空间外差光谱仪的工作原理和干涉图的产生机制, 提出了一种空间外差光谱仪的基频波长定标方法。沿干涉条纹法线方向求取像元相位, 通过对法线方向的像元相位进行线性拟合求取相位直线的斜率, 该相位斜率与干涉条纹法线方向的空间频率具有对应关系, 在获取两种已知波长的激光干涉图的相位斜率后即可确定该空间外差光谱仪的基频波长。四组波长数据的测试结果显示, 用该方法定标的基频波长具有很好的一致性, 标准差为0.044 nm。定标结果仿真的光谱与实测光谱完全一致, 证明了该方法的可行性。

A calibration method of fundamental frequency wavelength of space heterodyne spectrometer(SHS) is presented according to the operating principle of SHS and the generation mechanism of interferograms. Pixel phases along the normal direction of interferograms were calculated and linearly fitted to get the phase slopes corresponding to the space frequencies along the normal direction of interference fringes. When the phase slopes of laser interferograms for two known wavelengths were obtained, and then the fundamental frequency wavelength of the SHS was determined. The data test results of four groups of wavelengths show fundamental frequency wavelengths calibrated by this method have good consistency, and the standard deviation is 0.044 nm. In addition, the spectrum from simulated calibration results and that from actual measurement are consistent at a high degree, which implies the feasibility of the method.