为满足特定观测区域光波场的较高空间分辨率要求, 提出一种在衍射计算中引入虚拟光波场, 利用初始光波场的取样数表示观测平面任意区域衍射场的计算方法。通过应用该方法对具体实例进行模拟计算, 结果表明该方法在观测区域所获得的有效信息量增加, 所获得的衍射场空间分辨率可以达到5.2×10-3 mm/pixel, 而S-FFT计算获得的衍射场空间分辨率为26.6×10-3 mm/pixel。并且在基于该方法的彩色数字全息波前重建的实验研究中, 所得结果表明该方法能够取得更好的重建效果。

In order to satisfy the high spatial resolution requirements of light wave field in specific observation areas, a diffraction calculation method was presented . Through introducing a virtual optical wave field, it can use the sampling number of original light wave field to represent the diffraction field of arbitrary areas in the observation plane. Simulation experiments were carried out using the proposed method. The calculation results indicate that the method can increase the amount of effective information in the observation areas, and the spatial resolution of the diffraction field obtained by the method of virtual optical wave field can reach 5.2×10-3 mm/pixel. However, the spatial resolution of the diffraction field obtained by S-FFT is 26.6×10-3 mm/pixel. Moreover, the experimental results show that the proposed method can achieve better reconstruction performance in color digital holography wavefront reconstruction.