提出了一种用于长工作距离下显微成像的数字全息合成孔径方法。首先,在不同斜入射照明条件下记录多幅包含不同物光频谱范围的数字全息图。然后,利用每一幅全息图通过数字方法重构并放大物体强度像。最后,通过非相干叠加这些强度像得到分辨力提高且散斑噪声减小的合成物体强度像。理论分析和实验结果表明,此方法可应用于长工作距离下的原位显微观测。 A digital holographic synthetic aperture method for microscopic imaging under long working distance is proposed. First, a plurality of digital holograms containing different spectral ranges of light were recorded under different oblique incidence illumination conditions. Then, using each hologram to digitally reconstruct and magnify the object intensity image. Finally, by combining these intensities non-coherently, a composite object intensity image with improved resolution and reduced speckle noise is obtained. Theoretical analysis and experimental results show that this method can be applied to in situ microscopic observation under long working distance.