Abstract
Two-dimensional bar codes, such as the QR (Quick Response) codes, are frequently used with progress of the Internet and introducing the QR decoding function in the cellar phone. A bar code shows an individual identification number (ID) fundamentally. As the amount of information shown by one-dimensional bar codes is limited, two-dimensional bar codes have been developed. This paper studies the QR coding method and the redundancy characteristics of the QR coding are described. The information of the dotted picture can be multiplexed in the redundant area and multiplexing characteristics are evaluated.
