记录条件优化与再现像去噪提高数字全息像质 Improvement of Reconstructed Image of Digital Hologram by Using Optimizing Recording Conditions and Reducing Reconstruction Noises

从数字全息图的记录和再现两个过程，针对再现像的对比度和分辨力两个物理量，对分辨力板的离轴数字全息再现像质的提高进行了实验研究，得到如下结论，当记录元件感光面尺寸大于被记录的物体尺寸时，如果优化物光与参考光干涉条纹的空间频率，并采用频域窗口滤波法消除零级光和共轭像，以及采用空域中值滤波法消除高频随机噪声,可以明显地提高再现像质量。实验结果还表明，这一结论也适用于一般物体。 Investigations on improving the quality of reconstructed image of digital holography are carried out. Two processes of recording and numerical reconstruction are taken into account at the same time. Properties of resolution power and contrast of a resolution panel are studied. Some helpful conclusions are obtained. On condition that the aperture size of recording device is larger than an object size, the quality numerical reconstructed image can be improved if the frequency of interference fringe is optimized. In addition, the zero-order and conjugate images are eliminated and the stochastic noises are weakened. The experimental results show that these conclusions are also suitable to general objects.