Image encryption using separable amplitude-based virtual image and iteratively retrieved phase information

2001 ◽  
Vol 40 (10) ◽  
pp. 2165 ◽  
Author(s):  
Hsuan T. Chang
Keyword(s):  
Image Encryption ◽  
Virtual Image ◽  
Phase Information

Resolution in photoelectron microscopy

1991 ◽  
Vol 49 ◽  
pp. 458-459
Author(s):  
G. F. Rempfer
Keyword(s):  
Electron Microscopy ◽  
Electric Field ◽  
Ultraviolet Light ◽  
Uniform Field ◽  
Virtual Image ◽  
Lens System ◽  
Photoemission Electron Microscopy ◽  
Planar Electrode ◽  
Electron Lens ◽  
Photoemission Electron

In photoelectron microscopy (PEM), also called photoemission electron microscopy (PEEM), the image is formed by electrons which have been liberated from the specimen by ultraviolet light. The electrons are accelerated by an electric field before being imaged by an electron lens system. The specimen is supported on a planar electrode (or the electrode itself may be the specimen), and the accelerating field is applied between the specimen, which serves as the cathode, and an anode. The accelerating field is essentially uniform except for microfields near the surface of the specimen and a diverging field near the anode aperture. The uniform field forms a virtual image of the specimen (virtual specimen) at unit lateral magnification, approximately twice as far from the anode as is the specimen. The diverging field at the anode aperture in turn forms a virtual image of the virtual specimen at magnification 2/3, at a distance from the anode of 4/3 the specimen distance. This demagnified virtual image is the object for the objective stage of the lens system.

Electron holography of catalysts

1995 ◽  
Vol 53 ◽  
pp. 416-417
Author(s):  
A. K. Datye ◽  
D. S. Kalakkad ◽  
L. F. Allard ◽  
E. Völkl
Keyword(s):  
Heterogeneous Catalysts ◽  
High Surface ◽  
High Surface Area ◽  
Atomic Scale ◽  
Nano Particles ◽  
Phase Image ◽  
Electron Holography ◽  
Specimen Thickness ◽  
Phase Information ◽  
Particle Structure

The active phase in heterogeneous catalysts consists of nanometer-sized metal or oxide particles dispersed within the tortuous pore structure of a high surface area matrix. Such catalysts are extensively used for controlling emissions from automobile exhausts or in industrial processes such as the refining of crude oil to produce gasoline. The morphology of these nano-particles is of great interest to catalytic chemists since it affects the activity and selectivity for a class of reactions known as structure-sensitive reactions. In this paper, we describe some of the challenges in the study of heterogeneous catalysts, and provide examples of how electron holography can help in extracting details of particle structure and morphology on an atomic scale.Conventional high-resolution TEM imaging methods permit the image intensity to be recorded, but the phase information in the complex image wave is lost. However, it is the phase information which is sensitive at the atomic scale to changes in specimen thickness and composition, and thus analysis of the phase image can yield important information on morphological details at the nanometer level.

Implementation Color-Images Cryptography Using RSA Algorithm

2017 ◽  
Vol 7 (11) ◽  
pp. 181
Author(s):  
Ali Saleh Al Najjar
Keyword(s):  
Information Security ◽  
Image Encryption ◽  
Color Images ◽  
Public Key ◽  
Open Channels ◽  
Image Security ◽  
Rsa Algorithm ◽  
The Media ◽  
Encrypted Images ◽  
Difficult Issue

Absolute protection is a difficult issue to maintain the confidentiality of images through their transmission over open channels such as internet or networks and is a major concern in the media, so image Cryptography becomes an area of attraction and interest of research in the field of information security. The paper will offer proposed system that provides a special kinds of image Encryption image security, Cryptography using RSA algorithm for encrypted images by HEX function to extract HEX Code and using RSA public key algorithm, to generate cipher image text. This approach provides high security and it will be suitable for secured transmission of images over the networks or Internet.

Nature Inspired and Transform Based Image Encryption Techniques: A Comparative Study

2020 ◽  
Vol 5 (5) ◽  
pp. 1075-1092
Author(s):  
Bhagyashri Pandurangi R ◽  
Chaitra Bhat ◽  
Meenakshi R. Patil
Keyword(s):  
Comparative Study ◽  
Image Encryption

Image Encryption Based on Partitioning and Rearranged Pixels Position

2017 ◽  
Author(s):  
Jamila H. Al-A’meri ◽  
Salah T. Allawi ◽  
May M. Abbas
Keyword(s):  
Image Encryption
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