Research On Information Encryption Method Based On Optical Holography

In this era of information technology,advanced computer technology brings convenience to people,at the same time,the security of information transmission and storage has been greatly threatened.The rapid development of modern technology,there are a variety of encryption technology constantly.Due to the recent progress in the development of optical components and the increased technical performance of optical systems,optical cryptography has attracted much attention and has become a hot research topic.In this paper,after introducing the general situation of the research of optical encryption technology,We reviews several common encryption schemes,and analyzes the advantages and disadvantages of each scheme by theoretical analysis and simulation.This paper mainly analyses and simulate the existing computer generated hologram encryption technology.On this basis,we introduce the pixel scrambling technology and quick-response(QR)code technology to the process of holographic encryption.The main contents and structure of this paper are as follows:First of all,this paper gives an overview of the field of optical encryption,and introduces the basic theoretical knowledge related to optical encryption algorithm,so that we can grasp the optical encryption system as a whole,and lay a theoretical foundation for the follow-up study.Secondly,the existing three typical optical encryption schemes are analyzed,The first one is based on the double random phase encoding(DRPE)encryption system,which can be divided into DRPE encryption system based on Fourier transform,DRPE encryption system based on fractional Fourier transform and DRPE encryption system based on Fresnel diffraction;The second is optical encryption system based on the principle of interference;The third is the holographic encryption system;Each method is analyzed in detail,and the computer simulation is used to analyze the feasibility and security of each system.Put forward the possible shortcomings of the system,and give an improved scheme.Finally,in order to solve the problem that the noise of holographic encryption system is very large,and the security needs to be improved,the pixel scrambling technology and QR code technology are introduced into the process of holographic encryption.Improvement of the noise problem of the system mainly uses QR code which offers the main advantage of being tolerant to pollutant speckle noise,We view QR code as a “container” to be encrypted information into the container,while the external noise pollution will be great,but only in a certain range will not interfere with the internal information.In this way,we can decrypt the encrypted information without distortion.In order to improve the security of the system,we mainly use the pixel scrambling technology,the two electronic synthesis sparse matrix(ESSM)is used to randomly change the pixel position of the information to be encrypted.The two key can make the system effectively resist chosen plaintext attack(CPA),chosen ciphertext attack(CCA)and the known plaintext attack(KPA).The two keys and two reference light direction factors composed of a larger secret key space,which makes the attacker to use brute force attack algorithm decryption will be a very large workload,almost can not be completed.