Abstract: In order to enhance the diffraction efficiency of computational hologram, a novel way of generation and display of computational hologram is proposed, which is on the basis of advantages of Fourier hologram that has clear texture. The hologram is generated by Discrete Cosine Transform（DCT）, and then the hologram is reconstructed by Inverse Discrete Cosine Transform（IDCT）. The diffraction efficiency of the hologram produced by new method is increased by 13.65% and actual diffraction efficiency is improved 56.82%. Computer simulation results show that a hologram of good display effect and high diffraction efficiency is attained by this method.

Key words: holography, discrete cosine transform, Fourier hologram, diffraction efficiency

摘要： 为了提高计算全息图的衍射效率，以目前计算全息领域中显示纹理较为清晰的傅里叶全息图为基础，提出了一种新的全息图制作与显示方法。采用离散余弦变换生成相应的全息图，采用逆离散余弦变换对其进行重构。通过该方法所得的全息图的衍射效率比采用傅里叶算法的全息图的衍射效率提高了13.65%，有效衍射效率提高了56.82%，从计算机模拟再现的结果可以看出，得到了一种显示效果清晰的、衍射效率更高的新型全息图。

关键词: 全息术, 离散余弦变换, 傅里叶全息图, 衍射效率