针对Zhang 算法中参考光强取值范围较大的问题，在对全息成像原理仔细分析的基础上，提出通过综合考虑多个参数进而确定参考光强取值范围的方法，并用透射和反射同轴数字全息成像实验及基于实验结果的图像重建验证了进一步缩小参考光强取值范围的有效性。结果表明，采用该两步相移法结合进一步缩小参考光强取值范围的算法可以有效去除数字全息图中的零级像和孪生像而不降低全息像的重建质量，并能够降低大约20%的计算量。

The value searching range of reference light intensity is large in Zhang′ s algorithm. Based on an analysis of the theory of holography, we can take multiple parameters into consideration to further reduce the value searching range for the reference light intensity in two-step phase-shift digital holography and verify its effectiveness experimentally through in-axis transmission and reflection holography. It is shown that the twostep phase shifting holography combined with our proposed methods is effective in eliminating the zero-order image and twin image from hologram without deteriorating the reconstructed image but being benefit for saving computation cost about 20%.