傅里叶变换光谱仪非渐变相位误差的校正方法

Rapidly Changing Phase Error Correction of Fourier Transform Spectrometer

研究了相位误差起伏性较大、不满足随波数缓慢变化时的干涉型傅里叶变换光谱仪谱线相位误差的校正方法，根据实序列傅里叶变换的性质和离散傅里叶变换的性质，将过零单边干涉图采样数据和短双边干涉图采样数据分别作为复数序列的实部和虚部，组成一组复数序列，对此复数序列进行一次傅里叶变换，能够避免当相位误差起伏性较大时，对相位误差进行多项式拟合带来的较大误差，可以获得高精度的光谱。研究结果表明，当相位误差不能满足随波数缓慢变换时，传统的Mertz乘积法不能校正此时的相位误差，而实验中提出的方法能够校正此类相位误差，并且获得理想的光谱曲线，可以广泛地应用到干涉型傅里叶变换光谱仪的光谱反演中。

Rapidly changing phase error correction of interferential fourier transform spectrometer is researched. A complex number is reconstructed, which the real part is the data of zero-crossing single sided interferogram and the imaginary part is the data of short double sided interferogram. After once Fourier transform of the reconstructed complex number, the method can avoid the serious error caused by polynomial fitting of phase error as the phase error is rapidly changing. Then the high precision spectrum can be obtained, based on the characters of real number Fourier transform and discrete Fourier transform. The simulation results show that when phase error can＇t change gradually with wave number, conventional Mertz method can＇t correct the phase error which is serious, however, the method which is proposed by this paper can correct the phase error, and can gain perfect spectrum. The new method can be widely applied to spectral reducing of interferential Fourier transform spectrometer.