讨论了数字全息显微术(DHM)相位测量中显微物镜引入的附加相位的消除问题。在DHM相位重构中，对比分析了两步法和泽尼克多项式拟合两种附加相位补偿方法，进行了相应的实验研究，实现了多种生物细胞的相位重构。研究结果表明：两种补偿方法均能有效地消除DHM系统的相位误差。对于两步补偿法，由于补偿计算需要两组数字全息图，实验记录耗时，对记录系统稳定性要求高，但采用有、无样品相位相减的补偿算法简单，能够同时补偿显微物镜带来的球面附加相位和光学系统带来的其他相位畸变，相位重构的精度高。对于泽尼克多项式拟合补偿方法，补偿计算仅需一组数字全息图，在动态相位测量中具有特别的优势，但相位重构的误差随待测细胞高度和面积的增大而增大，为提高泽尼克相位补偿法的相位重构精度，需要保证物体的光学高度或者是物体的横向面积在一个较小的范围内变化。上述结果将为DHM用于生物细胞相位重构的研究和应用提供参考。

To obtain the real phase in digital holographic microscopy (DHM), it needs to compensate the additional phase induced by the microscope. Based on the theoretical analysis, both two-step compensation algorithm and Zernike polynomials fitting algorithm are employed to perform the phase reconstruction for biological cell. The obtain results show that both two-step compensation algorithm and Zernike polynomials fitting algorithm are useful for system phase compensation of DHM. In two-step compensation algorithm, since the subtraction operation is performed between the reconstructed phases with the object and without the object, the DHM system phase error can be compensated effectively while it is still time-consuming and needs high experimental stability for recording holograms. In Zernike polynomials fitting algorithm, only one group of digital holograms with the object is required for compensating the additional phase induced by the microscope, therefore it is suitable for the dynamic phase measurement while the constructed phase error increases with both the increase of object height and transverse area. To decrease the reconstruction phase error of Zernike polynomials fitting phase compensation algorithm, it is required to ensure that one of the variations of object optical height or transverse area to be a small value. The result supplies a useful tool for the study and application of biological cell phase compensation by DHM.