光学学报, 2014, 34 (6): 0626001, 网络出版: 2014-05-20
基于统计分析方法的同步移相干涉图位置配准
Position Registration for Simultaneous Phase-Shifting Interferograms Based on Statistical Analysis Method
物理光学 同步移相干涉仪 圆形域干涉图 位置配准 统计分析方法 physical optics simultaneous phase-shifting interferometer circular interferogram position registration statistical analysis method
摘要
使用同步移相干涉仪重建波前相位时,需要对移相干涉图进行准确的位置配准和目标区域确定以保证重建精度和相位解缠绕算法的成功实施。提出一种基于统计分析方法的圆形域同步移相干涉图位置配准技术,对一组包含不同相位分布的干涉图按照对应像素位置进行方差分布函数计算;利用最大组间方差法完成阈值分割,从而分离出干涉图像的背景与目标区域,通过梯度运算检测出目标区域的轮廓;利用改进Hough变换算法估计出各个轮廓的绝对位置和半径参数。数值仿真结果表明,当轮廓半径大于64 pixel时,该方法的配准精度可以达到0.5 pixel。通过建立自参考同步移相干涉仪对该方法的可靠性与实用性进行实验验证。
Abstract
In the wavefront phase reconstruction with simultaneous phase-shifting interferometers, accurate position registration and determination of object region for phase-shifting interferograms are needed to be done so that the reconstructed accuracy and the successful implement of phase unwrapping algorithm can be assured. A position registration technology based on statistical analysis method is presented to do with the circular simultaneous phase-shifting interferograms. According to all corresponding pixel positions, a variance distribution function is calculated from a group of interference patterns including different phase distributions. By using the maximal interclass variance method, the threshold segmentations are implemented, and so the background and object regions of interferograms can be sperated effectively. Furthermore, the edges of object regions are detected by applying gradient operation. With the improved Hough transform algorithm, absolute positions and radius parameters of each edge are estimated. With numerical simulation, the match precision of this method under the radius of greater than 64 pixel can be achieved up to 0.5 pixel. In addition, a self-referencing simultaneous phase-shifting interferometer is built to validate the reliability and practicability of the proposed method experimentally.
田枫, 白福忠, 吴亚琴, 徐永祥, 梅秀庄. 基于统计分析方法的同步移相干涉图位置配准[J]. 光学学报, 2014, 34(6): 0626001. Tian Feng, Bai Fuzhong, Wu Yaqin, Xu Yongxiang, Mei Xiuzhuang. Position Registration for Simultaneous Phase-Shifting Interferograms Based on Statistical Analysis Method[J]. Acta Optica Sinica, 2014, 34(6): 0626001.