在计算全息再现过程中，受空间光调制器(SLM)自身像素尺寸的影响，再现像的尺寸很小。基于计算全息中相位型全息图上的每一点都包含有物体各个点的全部相位信息，提出一种扩大计算全息再现像尺寸的方法。利用空分复用法，将SLM 分为四部分，每部分上分别加载含有物体不同场景的相位型全息图。在光学再现过程中，通过计算机控制加载到相应场景的全息图中相位光栅的变化，调节四个再现像的位置，实现了再现像的无缝拼接，从而得到计算全息大尺寸再现。实验结果证明了该方法的可行性。将该方法跟现有的几种方法进行对比，并进行了相应的讨论。

In the reconstruction of the computer-generated holography, the size of the reconstructed image is small because the pixel size of the spatial light modulators (SLM) is limited. As we know, each point of the phase-only hologram contains all the phase information of the image in computer-generated hologram. A method to enlarge the size of the reconstructed image is proposed. We divide the phase-only SLM into four areas by using spatial multiplexing method, and load the holograms on the corresponding areas of the SLM, respectively. In the optical reproduction, by changing the phase grating that loads onto the corresponding scene hologram, we can adjust the position of the reconstructed image. Therefore, we can achieve large-size reconstruction of the computer-generated hologram without tiling. The experiment verifies the feasibility of the proposed method. We compare the proposed method with other methods and discuss the results.