在输入面和频谱面上分别放置随机相位加密模板对图像数据进行加密是一种高密级的有效数据加密技术。在研究双随机相位数据加密技术的基础上, 结合数字全息技术和印刷技术的特点, 提出了一种新的双随机相位加密同轴相位全息标识(简称同轴相位全息标识)印刷防伪方法。理论分析证明了同轴相位全息标识方法能有效地恢复原始图像数据,仿真实验证明了该方法具有强抗随机干扰能力和抗位压缩性能。通过打印和扫描实验验证了同轴相位全息标识可以通过普通的数字印刷技术印制在证件等印刷品中作为防伪标识,印刷品中的同轴相位全息标识可以通过扫描输入计算机, 变换生成数字图像, 通过解密模板可从中恢复出原始图像数据。

It is a high quality data encryption technique by double random phase encoding with uniformly distributed random phase in both input and Fourier phases. Based on double random phase encoding technology and combination of digital holography and print technology, a new in-line phase holography mark printing anti-fake method with double random phase encryption is proposed. Theoretical analysis proves that the presented technology can recover data of the original image effectively, and the robust anti-interference and anti-bit compression characteristic is verified by computer simulation. Printing and scanning experiments demonstrates that the in-line phase holography mark can be printed on the printed matter (e.g. documents) as the anti-fake mark by common digital printing technique. The in-line phase holography mark can be input into a computer by scanning, and then converted to digital images. The original image data can be recovered by decryption mask.