光学相控器件调制误差对干涉投影条纹的影响

以马赫泽德干涉光路结构为基础,采用电光材料的光学相控技术产生用于光学形貌测量的干涉投影条纹。为了研究电光晶体作为光学相控器件的相位调制误差对干涉条纹质量的影响,建立了电光晶体对干涉条纹质量的模型,分析晶体折射率、平面度与波前调制的关系及其对干涉条纹质量的影响。仿真结果表明,电光晶体调制误差会影响干涉条纹质量。理想平面度下晶体折射率的畸变会使干涉条纹变形,折射率离散化阶数直接影响投影条纹的高次谐波成分,甚至导致投影条纹严重失真；折射率理想的情况下,晶体平面度的差异也会造成干涉条纹不同程度的形变。

Influence of modulation error of optical phase control device on interference projection fringe

Based on the optical path of the Maher Zed interferometer,the optical phase control technique is used to generate the interference projection fringe for the measurement of optical topography.In order to study the effect of phase modulation error of optical phase control device on the quality of interference fringes,the model of the quality of interference fringes is established.The relationship between the refractive index,the flatness and the wavefront modulation is analyzed,and the effect of those on the quality of interference fringes is also analyzed.The simulation results show that the modulation error of the electro-optical crystal will affect the quality of the interference fringes.The distortion of the crystal refractive index under the ideal planeness can cause the distortion of the interference fringes.The discrete order number of the refractive index directly influences the higher harmonic components of the projection fringes,and even causes the serious distortion of the projected fringes;when the refractive index is ideal,the difference of the crystal planeness will cause the different distortions of the interference fringes.