针对数字全息中零级像的存在影响数字再现像的质量,分析数字全息图的记录、再现原理及频谱特性,提出了一种利用有限脉冲响应滤波器消除全息图数字再现中零级像的方法。该方法只需记录一幅数字全息图,不需要相移器材或其他辅助设备,直接利用数字图像处理对数字全息图在空域进行预处理,消除全息再现时的零级像干扰。对比了数字模拟和实验拍摄到的全息图在应用有限脉冲响应滤波器消除零级像前后的再现结果,表明该方法可消除零级衍射像,改善重建像质量,并且算法简单。

Aiming at the zero-order image's effect on the quality of reconstructed images in digital holography, by analysis of spectrum characteristic as well as recording and reconstruction theory, a method of zero-order image elimination in digital holography by using of finite impulse response (FIR) filter is proposed. The method is based on only one hologram and the digital image processing for preprocessing the digital hologram in spatial domain to eliminate the zero-order image, free of phase modulator or any other extra-equipment. The comparison of elimination zero-order image in reconstructed hologram before and after using FIR filter in digital simulation and experiment presents that this method can eliminate the zero-order image and enhance the quality of reconstructed image with a simple algorithm.