Optical encryption and multiplexing of personal identification information using orthogonal code
Md. Nazrul Islam · Optical Engineering · 2006
A new technique is proposed for optical encryption and multiplexing of binary characters and images used for personal identification information. Different binary images can first be encrypted using orthogonal code and then multiplexed together in the spatial domain. The resulting encrypted single image provides security as well as makes efficient use of storage and/or transmission capacity. The image can finally be decrypted and the individual input images can be decoded employing the same orthogonal code set. Because of the orthogonal nature of the code used, the encryption and decryption processes do not deteriorate the quality of the images employed. Also, the proposed technique involves a very simple architecture, as it does not require any mathematical transformation.