两步广义相移干涉术的光学实验验证

Optical experimental verification of two-step generalized phase-shifting interferometry

提出了一种基于两步广义相移干涉术的波前再现技术以及基于衍射场统计特性的未知相移值提取算法,并且进行了光学实验验证.该方法中可仅利用两幅干涉图及一次不需精确预设的未知相移,参照物光光强和参考光光强,即可通过计算提取真实的相移量,进而恢复出物波波前复振幅,而无需借助傅里叶谱分析或数字滤波等操作.在光学实验中,对借助于空间光调制器(SLM)的间接输入和三维漫反射物体直接输入两种情况进行了详细地研究,得到的光学实验结果验证了所提方案的有效性和可行性.

A wavefront reconstruction technique by two-step generalized phase-shifting interferometry （GPSI） is proposed and verified by optical experiments. According to the statistical characters of the diffractive field,a blind extraction algorithm is developed,by which the unknown phase shift value in interferometry can be successfully extracted. The proposed method can retrieve the real amplitude of object wave field by using two interferograms,the recorded object and reference wave intensities,and an extracted phase shift,without the assistance of additional Fourier spectrum analysis or digital filtering. In optical experiments,the feasibility of this method for both the indirect object （digital images cast on a spatial light modulator,SLM） and the direct three-dimensional diffused object inputs has been discussed and investigated in detail,and the experimental results have convincingly verified the usefulness and effectiveness of this scheme in practice.