无透镜傅里叶变换数字全息中的相位补偿

摘要

The phase accuracy of numerically reconstructed images directly affects the result of the digital holographic measurement .How to find the phase distortion and adopt corresponding method to automatically correct the distortion is challenging .The phase correction problem of lensless Fourier transform digital holographic was analyzed .When reconstruct the numerical wave surface by means of single Fourier transform , there is an additional quadratic phase factor inducing the phase distortion of reconstructed images .The digital phase mask was calculated based on multiple-profile calculation by means of the least square method for curve fitting , the phase distribution was corrected .The theoretical analysis and experimental prove that it is better to correct phase distortion compared with frequently -used two-profile method , the result is helpful for the study of phase correction .%　　数值再现像相位的准确性直接影响到数字全息检测的结果。为了找出再现过程中存在的相位畸变并采取相应的方法达到自动补偿，对无透镜傅里叶变换数字全息中的相位补偿问题进行了研究。因为经过单次傅里叶变换法进行数字波面重构时，存在一个附加的二次相位因子，该附加因子造成了再现像的相位畸变。采用最小二乘曲线拟合方法，通过多剖面计算得出数字相位掩膜进而对相位分布进行校正，并进行了理论分析和对比实验验证。结果表明，与常用的二剖面方法相比，能够对相位畸变进行更好的校正。这一结果对相位补偿问题的研究是有帮助的。