非相干全息术可以利用非相干光源获得物体的全息图。利用迈克尔逊干涉仪搭建了非相干同轴数字全息成像系统,利用菲涅尔衍射理论分析系统的点扩散函数(PSF),使用CCD记录全息图并在计算机中进行数值重建,研究广义相移数字全息干涉术在非相干同轴数字全息成像系统中的应用。结果表明,基于迈克尔逊干涉仪的非相干同轴数字全息成像系统可以实现白光光源照明下物体全息图的快速记录,三步广义相移数字全息干涉术应用于系统,能够克服使用移相器的非相干同轴数字全息术对系统稳定性要求较高的缺点,可以去除孪生像和零级像,获得清晰的数值重建像。本文系统的横向放大率为1.6倍时,分辨率可达45lp/mm。
Incoherent holography can record digital holograms under incoherent illumination. This paper builds an incoherent on-axis digital holography imaging system based on Michelson interferometer,analyzes the system's point spread function according to the Fresnel diffraction theory, and uses a CCD to record holograms,and the results of numerical reconstruction are given on the computer. The generalized phase-shifting interferometry is introduced to the incoherent on-axis digital holography imaging system. The experimental results show that the incoherent on-axis digital holography imaging system based on Miehelson interferometer can record digital holograms under incoherent illumination rapidly. The three, step generalized phase-shifting interferometry can be successfully combined with the incoherent on-axis digital holography imaging system. Compared with the incoherent on-axis digital holography imaging system which uses a phase shifter, this system does not require so high stability. A clear reconstruction focusing at different planes is obtained with no conjugate image or zero-order image. The resolution of the system can reach 45 lp/mm when the lateral magnification of the system is 1.6.