为了进行3维物体全息图的快速运算, 在迭代傅里叶变换算法基础上, 通过分析透镜的傅里叶变换性质, 采用编码球面相位因子的方法, 将全息图平行光再现等效为点光源再现。将球面相位因子加入到迭代运算中, 获得了具有深度特征的3维物体全息图; 同时利用球面相位因子查表运算法简化了相位因子的计算, 提高了算法的迭代速度,并基于空间光调制器进行了3维物体的再现实验。结果表明, 该算法具有良好的收敛特性, 计算的全息图能够在不同距离的像面实现对应层面的物场再现, 具有3维的视觉效果。

In order to calculate hologram of 3-D objects quickly, a novel computer-generated hologram method based on iterative Fourier transform was proposed. Considering Fourier transform characteristics of a lens, parallel light reconstruction was changed to point lamp-house irradiation by introducing coding spherical phase factors. Adding the spherical phase factor to iterative computation process to represent depth characteristics, the holograph of 3-D object was obtained. A lookup table was used to reduce the influence of phase factor operation and improve the speed of iterative calculation. The experiment based on spatial light modulator shows that the convergent speciality of this algorithm is good and computational holograph can reconstruct matching object layer in different distance, which has three-dimensional vision effect.