基于希尔伯特变换的干涉条纹相位解调新算法

A Novel Hilbert Transform Algorithm for Phase Evaluation from Fringe Pattern

提出了一种新的应用希尔伯特变换解调干涉条纹相位的算法,可以从单幅干涉条纹图中解调出全场相位分布.在实际应用中,常借助傅里叶变换实现希尔伯特变换算法,但是会忽略负频率成分,造成相位信息的丢失.对于相位分布非单调变化的干涉条纹,提出了一种判断函数,用来计算相位信息零频率点的分布.利用相位的零频率点分布构造了一个二元模板,使用该模板对本文提出的两次希尔伯特变换法产生的包裹相位图进行修正.对修正后的包裹相位图进行解包裹处理,可以得到连续的全场相位分布.对该方法用计算机模拟进行了验证.

A novel Hilbert transform algorithm for detecting phase from fringe pattern is proposed.Only one interference pattern is required for the phase evaluation.In practice,the Hilbert transform based on the Fourier transformation eliminates all negative frequency components,and any phase variation in the fringe pattern having negative local spatial frequency can not be correctly reconstructed.A procedure for detection of regions having zero spatial frequency in the fringe pattern is proposed by an estimation function for complicated phase distribution.A binary matrix is used for modifying wrapped phase of complicated phase distribution fringe pattern, and a method for removing the bias component by twice Hilbert transform is proposed.The correct values of phase is obtained by an unwrapping process.The performance of the proposed method is evaluated by computer simulation.