无透镜数字全息显微图像增强方法及其应用研究

发布时间：2018-09-03 08:34

【摘要】：数字全息是一种记录波场三维信息的新型方法,它利用数字摄像机代替全息胶片并以数字化的方式存储和捕获物体波,然后用计算机仿真光源再次照射全息图重建出物体波,从而获得物体原始复振幅信息。相比基于胶片的全息技术,数字全息不仅可以重建物体相位信息,而且成像方便、快速且简单,在图像处理技术方面蕴含着强大性以及可操纵光场的技能,因此广泛应用于信息加密、显微观测、医学诊断、元器件检测等领域。数字全息的主要研究内容包含成像光路、图像增强算法以及实际应用。本文研究数字全息的知识背景与最新进展,分析数字全息成像的理论和方法步骤,研究如何抑制数字全息重建中的斑点噪声和共轭像,实现数字全息在信息加密领域的应用。论文的主要研究内容和创新点如下:1)研究数字全息中的“斑点”现象,总结斑点噪声的特征和模型;利用计算机模拟实现无透镜数字全息显微光路,采集到的全息图像容易存在影响图像分辨率的斑点噪声;分析现有的图像增强算法,给出一种融合算法,并与其它算法的实验数据展开比对分析。2)提出利用高斯过程回归求解TIE方程算法来抑制全息图像中的共轭像,利用计算机仿真实验过程,实验结果证实提出方法比传统的GS方法去噪性能好。3)研究一种多平面菲涅尔数字全息与Arnold变换相融合的图像加密方法,给出详细的加密理论和过程,仿真实验结果证实该方法具有可操作性、稳定性和安全性。
[Abstract]:Digital holography is a new method of recording three-dimensional information of wave field. It uses digital camera instead of holographic film and stores and captures object waves in a digital way, and then reilluminates hologram to reconstruct object waves with computer simulation light source. The original complex amplitude information is obtained. Compared with holography based on film, digital holography can not only reconstruct phase information of object, but also be convenient, fast and simple in image processing. Therefore, it is widely used in the fields of information encryption, microscopic observation, medical diagnosis, component detection and so on. The main research contents of digital holography include imaging optical path, image enhancement algorithm and practical application. This paper studies the knowledge background and recent development of digital holography, analyzes the theory and method of digital holographic imaging, studies how to suppress speckle noise and conjugate image in digital holographic reconstruction, and realizes the application of digital holography in the field of information encryption. The main contents and innovations of this paper are as follows: (1) the "speckle" phenomenon in digital holography is studied, the characteristics and models of speckle noise are summarized, and the microscopic optical path of lensless digital holography is realized by computer simulation. The collected holographic image is prone to speckle noise which affects the resolution of the image, the existing image enhancement algorithms are analyzed, and a fusion algorithm is presented. Comparing with the experimental data of other algorithms, the author proposes to use Gao Si process regression to solve the TIE equation algorithm to suppress the conjugate image in the holographic image, and to simulate the experimental process by computer. The experimental results show that the proposed method has better denoising performance than the traditional GS method. (3) A multi-plane Fresnel digital holography and Arnold transform image encryption method is studied, and the detailed encryption theory and process are given. The simulation results show that the method is feasible, stable and safe.
【学位授予单位】：深圳大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN26;TP391.41

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