周期物体的衍射光场在垂直于传播方向的平面上具有周期性,衍射光场有着点对点的关联。在此基础上,提出基于反射型物体的高阶周期衍射关联成像方案,给出成像性能的理论分析和数值仿真。研究结果表明:对于反射型物体的周期衍射关联成像,当针孔点阵列的孔数确定时,随着阶数的增大,成像的可见度增大,信噪比下降。而当阶数确定时,随着针孔点阵列孔数的增加,成像的可见度和信噪比都会减小。与传统热光关联成像相比,光源大小可控,成像装置简单灵活,这为关联成像的实用化提供一种可参考方法。
The light field is periodic in the plane which is perpendicular with the direction of its propagation and the diffraction field has a point-to-point correlation. On this basis, a high-order periodic diffraction correlation imaging scheme for reflective objects was presented. The performance of the proposed correlation imaging scheme was discussed by theoretical analysis and numerical simulation. The results show that the visibility of the periodic diffraction correlation imaging is enhanced while the signal-to-noise ratio is decreased with the larger order when the pinhole numbers of the pinhole array are determined. The visibility and signal- to-noise ratio are decreased with the pinhole number when the order numbers axe determined. Compared with the traditional thermal correlation imaging, the scheme has advantages of size of the light source being controlled and the equipments of the experiment being simplified. Hence, it provides a reference method for the realization of correlation imaging