本文发展了一种基于傅立叶变换的相位误差预估技术来计算干涉条纹的相位误差,从而得出干涉式示差折光仪的理论检测极限的新方法。本文通过模拟计算了相位误差的精度为3.4×10-8×2π rad,即折光仪理论检测极限为2.2×10-12 RIU。模拟结果与以往文献中实验数据对比证明此技术的可行性。同时,我们也详细讨论了干涉条纹的相位误差的精度与CCD探测器的像元尺寸、比特深度以及干涉条纹的空间周期的关系,模拟结果给出了优化的CCD参数及干涉系统参数。这种技术为进一步实现示差折光系统的实验参数选择以及检测极限的研究提供了理论指导。

Without considering the noise,this paper developed a new phase error estimation technique based on Fourier transform to calculate the phase error of interference fringes. In this paper,the accuracy of phase error was calculated by simulation is 34×10-8×2π rad. The simulation results were compared with the actual experiment to prove the feasibility of this technique. The accuracy of the phase error of the interference fringes is related to the pixel size of the CCD detector,the bit depth and the space period of the interference fringes,which was also discussed in detail in this paper. This technique is conducive to the refractive index of the CCD detector parameter selection and detection limit of the study.