彩色全息图的计算机产生和数字再现

提出了一种基于色彩合成以及菲涅尔衍射原理,用计算机产生全息图并用数字方法再现彩色全息图的方法。该方法的第一步是将物体的彩色RGB图像分离为三基色强度图,再利用博奇编码的方法制成修正离轴参考光分色计算机全息图;第二步是分别对分色全息图在频域进行调制以实现用原参考光真实再现原始物光波。通过滤波消除零级衍射及共轭像的影响,获得了所需要的实像并提高了像质。提供的实验是选用一幅RGB图像作为原始物体,给出了用博奇编码法制成的全息图以及最后经色彩合成获得的再现像。结果表明,该方法能使各分色全息图的再现像准确重合,解决了在色彩合成时容易出现的色串扰问题。

Computer generating and numerical reconstructing color hologram

A method, which is based on the theories of color synthesizing and Fresnel diffraction, is proposed for computer generating hologram and numerical reconstructing color object. First, the object's RGB image is separated to three primitive color intensity images. And the modified off axis reference beam CGHs are generated through the method of Burch coding. Then the primitive color holograms are modulated in the frequency domain to reconstruct object by original reference waves. Through frequency filtering, the zero order diffraction and twin image can be suppressed, and the quality of the reconstructed image is improved. A RGB image is chosen as the original object for the demonstration. The holograms produced by Burch coding and the reconstructed images gained through color synthesizing are presented. The results show that using this method, the reconstructed images of the primitive color holograms can be superposed precisely, the problem of color disturbing which often appears in color synthesizing is solved effectively.