基于光纤干涉投影的子孔径拼接测量方法

Sub-aperture stitching measurement method based on fiber optic interference projection

目的:针对大动态范围复杂曲面的面形检测需求,提出了一种基于光纤干涉投影的子孔径拼接测量方法。方法:通过CCD相机与干涉条纹间的关系作为子孔径划分的依据,利用光纤干涉投影测量系统采集各子孔径的面形数据,由此结合所提出的加权算法将各子孔径进行拼接来获取全口径面形。结果:仿真分析与实验验证表明,通过所提出方法获取的拼接面形连续光滑,且与全口径真实面形RMS值偏差为1.8458μm,达到了微米量级的检测精度。结论:该测量方法具有检测精度较高、动态测量范围大等特点,从而为各类复杂曲面提供了一种有效的面形检测方法。

Aims:Aiming at the measurement needs of various complex surfaces with large dynamic ranges,a sub-aperture stitching testing method based on the fiber optic interference projection was proposed.Methods:According to the relationship between fringe patterns and the CCD camera,sub-apertures were divided and sequentially measured with the proposed optical fiber interference projection testing system;and the tested surface of each sub-aperture could be reconstructed with high accuracy and be stitched to obtain the full-aperture testing result.Results:The simulation results showed that the stitching surface obtained by the proposed method agreed well with the full-aperture nominal surface;and the deviation value of root mean square between the stitching surface and the nominal surface was 1.8458μm,reaching a micron detection accuracy.Conclusions:The proposed method is high in measurement accuracy and large in dynamic range,thus providing an effective testing method for various complex surfaces.