한국광학회 학술대회논문집

시각 암호와 간섭계를 이용한 광 암호화

이상수, 서동환, 김종윤, 박세준, 신창목, 김수중, 박상국

Published Aug 1, 2000• 0 citations

Abstract

In this paper, we proposed an optical encryption method based in the concept of visual cryptography and interferometry. In our method a secret binary image was divided into two sub-images and they were encrypted by ‘XOR’ operation with a random key mask. Finally each encrypted image was changed into phase mask. By interference of these two phase masks the original image was obtained. Compared with general visual encryption method, this optical method had good signal-to-noise ratio due to no need to generate sub-pixels like visual encryption.

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Optical encryption system using visual cryptography and virtual phase images

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